研究者詳細 - 片岡　淳

雷発生時のガンマ線、新潟十日町・松代で世界初の画像化に成功

新聞・雑誌

新潟日報（朝刊）

2022年12月
早大ら、放射化イメージングで薬物動態の可視化へ

インターネットメディア

Optronics News Letter

2022年11月
戦略的創造研究推進事業における令和３年度新規研究総括および研究領域の決定について

インターネットメディア

2021年10月
Galaxy-Size Bubbles Discovered Towering Over the Milky Way

新聞・雑誌

Quanta Magagize

2021年01月
X線からガンマ線まで同時に可視化～早大・阪大が共同

新聞・雑誌

科学新聞

2020年10月
輝くブラックホールの謎～銀河中心部繰り返し爆発か

新聞・雑誌

日本経済新聞（日刊）

2019年09月
天の川銀河「巨大ガンマ線バブル」の謎に迫る

academist Journal

2018年08月
早大・東大・金沢大・理研、銀河中心「巨大ガンマ線バブル」の謎を解明－1000万年前の大爆発をX線で検証

日経新聞電子版

日経新聞電子版

2018年07月
4.4MeVのガンマ線可視化 ― 早大が小型カメラ開発

科学新聞

2018年06月
ガンマ線検出のカメラ～陽子線治療など応用早大など開発

日経産業新聞

2018年06月
見えない光で未知を観る！

BSジャパン「科学ミチル世界は未知で満ちている」

BSジャパン7ch : 木曜夜 8:55

2018年03月
陽子線治療精度を向上早大が体内進路可視化

化学工業日報

2018年02月
理系マイナビ 2019 SPECIAL INTERVIEW volume.51

マイナビ

2017年12月
研究者の横顔

NTT NTTファシリティーズ・ジャーナル

2017年11月
Medical gamma-ray camera is now palm-sized

Science Daily

2017年05月
世界最軽量５８０グラム実現ガンマ線可視化カメラ

科学新聞科学新聞

2017年05月
早大など、ガンマ線を3D画像に手のひら大のカメラ

日経新聞日経新聞全国版

2017年05月
セシウムの分布可視化―早大、ドローン使い空撮

日経産業新聞日経産業新聞

2016年09月
星空案内人 ― 福島で活躍中コンプトンカメラ

山形新聞山形新聞

2016年07月
ガンマ線撮像用コンプトンカメラの高性能化に成功～除染のさらなる効率化、環境調査、医療、理学応用へ期待～

静岡第一テレビ、日経産業新聞、日刊工業新聞

2014年07月
セシウム強度効率測定～浜ホト・早大ガンマ線カメラ

新聞・雑誌

日本経済新聞（日刊）

2013年09月
数分で放射線画像化

新聞・雑誌

朝日新聞（日刊）

2013年09月
ガンマ線を素早く画像化－「福島第一」除染に威力

新聞・雑誌

中日新聞

2013年09月
新種の「毒蜘蛛パルサー」発見

読売新聞、東京新聞、中日新聞

2012年03月
Waseda University's Fermi LAT Team

新聞・雑誌

Fermi News Letter

2010年05月
フェルミ衛星で銀河に付随する「巨大な粒子雲」からのガンマ線を発見

科学新聞

2010年04月
LuAG結晶用い放射線検出器開発ー次世代がん診断装置向け

化学工業新聞

2009年07月
フェルミ衛星が新種のガンマ線銀河を発見

毎日新聞

2009年06月
NASA’s Fermi Finds Gamma-Ray Galaxy Surprises

インターネットメディア

NASA

2009年05月
解像度5倍がん早期発見 ― 光センサー小さく

新聞・雑誌

日経産業新聞

2008年05月

▼全件表示

論文

Scintillation of polyester fabric and clothing via proton irradiation and its utilization in surface imaging of proton pencil beams

Seiichi Yamamoto, Tomohiro Yamashita, Masao Yoshino, Kei Kamada, Akira Yoshikawa, Teiji Nishio, Jun Kataoka

Scientific Reports 14 ( 1 ) 2024年12月

　概要を見る

In the realm of radiation therapy, a conspicuous obstacle lies in the dearth of external observation concerning radiation beams aimed at the patient. While real-time monitoring of such beams on the patient's surface during therapy holds promise, the imaging of particle beams has thus far proven to be a formidable task. Here, we show our discovery of polyester fabrics and cloths as auspicious scintillating materials, ideally suited for the visualization of radiation beams upon the patient's surface. The light output of polyester fabrics ranged from 10 to 20% of that observed in plastic scintillators. When exposed to spot scanning proton beams, clear beam spots emerged on the surface of the polyester cloths. The movement of these scanning beams was effectively captured using a CMOS camera in a light-shield-free with lights-off environment. The resulting images provided a means for evaluating spills of the proton beams. The inherent flexibility of polyester fabrics and clothing enhances their appeal for applications in the intricate landscape of radiation therapy, promising a bright future for surface beam imaging endeavors.

DOI PubMed

Scopus
Development and performance evaluation of a thin GAGG:Ce scintillator plate for high resolution synchrotron radiation X-ray imaging

Masao Yoshino, Seiichi Yamamoto, Kohei Nakanishi, Katsunori Yogo, Kei Kamada, Nanase Koshikawa, Jun Kataoka, Akira Yoshikawa

Journal of Instrumentation 19 ( 10 ) P10030 - P10030 2024年10月

　概要を見る

Abstract

Scintillator-based X-ray imaging detectors are pivotal in numerous scientific and practical domains, including medical imaging, food and device inspection, and security monitoring. Recent advancements have spurred interest in 4D X-ray imaging using synchrotron radiation, necessitating higher temporal resolutions. Consequently, this places stringent demands on X-ray detector technology, especially when X-ray energy exceeds 20 keV. The selection of a suitable scintillator material is crucial for achieving optimal timing resolution, yet it poses a significant challenge in dynamic X-ray imaging. This study delves into the optimization of scintillator properties and their impact on spatial resolution and light output, elucidating the performance of Ce-doped Gd₃Ga₃Al₂O₁₂ (GAGG:Ce) scintillators for X-ray imaging applications. We developed a micro X-ray imaging detector using a 100 μm-thick GAGG:Ce scintillator plate and conducted X-ray imaging tests at the Aichi SR facility. The results demonstrated that the resolution, quantified as the chart slit width at a contrast transfer function (CTF) value of 10%, reached 2 ∼ 3 μm with a 4× lens, 0.52 μm± 0.03 μm with a 20× lens, and 0.42 μm± 0.01 μm with a 40× lens. Although the results of this study did not achieve a spatial resolution nearing the effective pixel size of the 40× lens, the text also elucidates the underlying reasons for this limitation. Furthermore, we compared the X-ray sensitivity of our GAGG:Ce scintillator plate with that of a commercial LuAG:Ce scintillator, revealing an approximately 1.5-fold increase in light output. As a demonstration, transmission images of dried small fish were captured using the GAGG:Ce scintillator plate and the developed X-ray imaging system. These findings highlight the potential of the X-ray imaging detector devised in this study for future generations of X-ray imaging applications.

DOI
Development of a single photon emission microscope system with ∼200 μm spatial resolution

Seiichi Yamamoto, Kohei Nakanishi, Jun Kataoka

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1067 169673 - 169673 2024年10月

DOI

Scopus
MeV gamma-ray detector on the 50-kg class satellite

Kazuo Tanaka, Jun Kataoka, Ryoji Iwashita, Ryohei Mori, Tomoya Suga, Shojun Ogasawara, Moeri Tao, Yoichi Yatsu, Chujo Toshihiro, Shinichiro Takeda, Mitsunobu Onishi

Space Telescopes and Instrumentation 2024: Ultraviolet to Gamma Ray 98 - 98 2024年08月

DOI

Scopus
Challenge of 50 kg-class satellite to open up MeV gamma-ray astronomy

J. Kataoka, R. Iwashita, K.S. Tanaka, R. Mori, S. Ogasawara, T. Suga, N. Koshikawa, K. Watanabe, M. Yasuda, H. Kobayashi, D. Kobayashi, K. Otsubo, A. Ohira, Y. Amaki, Y. Arai, K. Tashiro, Y. Ozeki, Y. Kawaguchi, D. Yoshimura, H. Yoshida, K. Takahashi, Y. Yatsu, T. Chujo, H. Nakanishi, M. Onishi, S. Takeda

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1065 169518 - 169518 2024年08月

DOI

Scopus
Development of a phoswich imaging detector to simultaneously acquire neutron and gamma photon images

Seiichi Yamamoto, Masao Yoshino, Kohei Nakanishi, Kei Kamada, Akira Yoshikawa, Hiroki Tanaka, Jun Kataoka

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1065 169484 - 169484 2024年08月

DOI

Scopus
Multi-energy in-vivo imaging of multiple contrast agents in a mouse using MPPC-based photon-counting CT

Daichi Sato, Makoto Arimoto, Ayumi Ishiguro, Fitri Lucyana, Takahiro Tomoda, Kenichiro Okumura, Hiroki Kawashima, Satoshi Kobayashi, Kazuhiro Murakami, Jun Kataoka, Mayu Sagisaka, Shinsuke Terazawa, Satoshi Shiota

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1064 169337 - 169337 2024年07月

DOI

Scopus

2

被引用数

(Scopus)
ComptonNet: A direct reconstruction model for Compton camera

S. Sato, K. S. Tanaka, J. Kataoka

Applied Physics Letters 124 ( 25 ) 2024年06月

　概要を見る

A Compton camera is a gamma-ray imaging device, especially in the sub-mega-electron volt to higher than mega-electron volt range. Compton cameras have recently attracted attention as an environmental survey tool. However, owing to their limited sensitivity, Compton camera images often suffer from various artifacts, especially when the event statistics are low. To address this challenge, several deep learning models have been proposed to enhance the quality of reconstructed images with limited statistics. However, during the event selection phase of a typical Compton camera image reconstruction, a significant number of events that potentially reflect the source distribution are generally discarded. Effective utilization of these discarded events has the potential to estimate an accurate source distribution from limited statistical data. Thus, we initially developed ComptonNet-v1, a framework designed to directly estimate source distribution by integrating all measured events into a single model. To explicitly implement the difference in contribution between events that interact solely with scatterers, solely with absorbers, or with both, we developed ComptonNet-v2, which integrates these events individually. Consequently, our proposed models exhibited superior performance in both quantitative and qualitative assessments compared with existing models, even under low event statistics. In the future, we plan to implement a more memory-efficient model to estimate the distribution of complex source shapes.

DOI

Scopus
Experimental concept validation of a proton therapy range verification system using scattered proton measurements

S. Sato, H. Yokokawa, M. Sagisaka, Y. Okazaki, R. Iwashita, S. Yoshida, K. S. Tanaka, S. Yamamoto, T. Yamashita, Y. Kobashi, J. Kataoka

Applied Physics Letters 124 ( 21 ) 2024年05月

　概要を見る

In recent years, the application of positron emission tomography (PET) for the dose range verification of proton therapy has been proposed. However, the positron distribution is determined by the nuclear reaction cross section; hence, PET may not accurately reflect the dose range primarily influenced by ionization. Consequently, a proton dose range verification system based on scattered proton measurements has been suggested owing to the similarity in the reaction cross section between Rutherford scattering and ionization. While previous investigations have only verified the feasibility of dose range estimation through simple simulations, the objective of this study is to demonstrate this feasibility through experimental investigation. In this paper, we established an experimental framework for capturing scattered protons and introduced an algorithm that compares measured signal patterns with a reference database to estimate the dose range. A therapeutic beam was irradiated onto the abdominal region of a human phantom, and scattered protons were measured using scintillation detectors placed on the phantom surface. Consequently, the dose range was estimated with error margins of 4.22 ± 3.68 and 0.60 ± 1.03 mm along the beam axis and perpendicular directions to the Bragg peak, respectively. While providing the same level of Bragg peak positioning accuracy as conventional methods, our system features small size, cost-effectiveness, and system simplicity. One notable limitation of our method is the challenge in achieving precise detector positioning, which is crucial for accurate dose range estimation. Future research will focus on improving detector-position accuracy and exploring advanced algorithms for signal analysis to further refine dose range estimations.

DOI

Scopus
Construction and initial performance evaluation of a newly developed plant PET system

Seiichi Yamamoto, Hiroshi Watabe, Mitsutaka Yamaguchi, Nobuo Suzui, Naoki Kawachi, Jun Kataoka

Journal of Instrumentation 19 ( 04 ) 2024年04月 [査読有り]

DOI
A method for estimating the incident directions of alpha particles in 2-dimensional trajectory images in a GAGG plate

Seiichi Yamamoto, Masao Yoshino, Kohei Nakanishi, Kei Kamada, Akira Yoshikawa, Jun Kataoka

Journal of Instrumentation 19 ( 04 ) T04010 - T04010 2024年04月

　概要を見る

Abstract

An imaging technique utilizing a scintillator plate in conjunction with a magnifying unit and a cooled electron multiplying charge-coupled device (EM-CCD) camera shows promise for capturing high-resolution trajectory images. Nevertheless, in the 2-dimensional trajectory images, the incident directions of the alpha particles entering the scintillator plate remained unknown due to the line-shaped trajectories. To elucidate the incident directions in our trajectory images, we conducted experiments capturing trajectory images of alpha particles under off-focus conditions. To capture off-focus images of alpha particles, we systematically varied the distance between the GAGG plate and the lens during imaging using an americium-241 (Am-241) source. Through images obtained at different distances between the GAGG plate and the lens, we successfully acquired trajectory images with varying degrees of off-focus, revealing that trajectory images focused on the upper surface of the GAGG plate exhibited blurred and wider trajectories in the deeper regions, making the incident directions of the alpha particles evident. We conclude that the proposed off-focus method for trajectory imaging of alpha particles holds promise for estimating the incident directions in the trajectory images.

DOI
A novel method for efficiently measuring the non-proportionality of scintillators between light output and alpha particle energies from 1.8 MeV to 5.2 MeV

Seiichi Yamamoto, Masao Yoshino, Kohei Nakanishi, Kei Kamada, Akira Yoshikawa, Jun Kataoka

Journal of Instrumentation 19 ( 04 ) P04011 - P04011 2024年04月

　概要を見る

Abstract

It is known that scintillators exhibit non-proportional behavior between light output and the energy of gamma photons or beta particles. However, the non-proportionality between light output in scintillators and the energy of alpha particles has not been extensively measured, likely due to the challenges associated with preparing alpha particles with varying energies. To address this issue, we propose a novel method to modulate the energy of alpha particles using an americium-241 (Am-241) source covered with different numbers of Mylar films. By irradiating various scintillators, including GAGG, GGAG, YAP(Ce), and plastic scintillator, with alpha particles of different energies, we measured and evaluated the non-proportional response of these scintillators. We then compared the measured response as a function of incident energy to a simulation, which assumes a proportional response to evaluate the non-proportionality. For all the scintillators tested, non-proportionality was observed; the light output per MeV at 1.8 MeV ranged from 0.60 to 0.81 of the values observed at 5.2 MeV. The non-proportional response was largest for plastic scintillator (0.60) and smallest for GAGG (0.81). We conclude that the proposed method could be an efficient means of measuring the non-proportionality of scintillators between light output and alpha particle energies

DOI
A triple-imaging-modality system for simultaneous measurements of prompt gamma photons, prompt x-rays, and induced positrons during proton beam irradiation

Seiichi Yamamoto, Hiroshi Watabe, Kohei Nakanishi, Takuya Yabe, Mitsutaka Yamaguchi, Naoki Kawachi, Kei Kamada, Akira Yoshikawa, Masayasu Miyake, Kazuo S Tanaka, Jun Kataoka

Physics in Medicine & Biology 69 ( 5 ) 055012 - 055012 2024年02月

　概要を見る

Abstract

Objective. Prompt gamma photon, prompt x-ray, and induced positron imaging are possible methods for observing a proton beam’s shape from outside the subject. However, since these three types of images have not been measured simultaneously nor compared using the same subject, their advantages and disadvantages remain unknown for imaging beam shapes in therapy. To clarify these points, we developed a triple-imaging-modality system to simultaneously measure prompt gamma photons, prompt x-rays, and induced positrons during proton beam irradiation to a phantom. Approach. The developed triple-imaging-modality system consists of a gamma camera, an x-ray camera, and a dual-head positron emission tomography (PET) system. During 80 MeV proton beam irradiation to a polymethyl methacrylate (PMMA) phantom, imaging of prompt gamma photons was conducted by the developed gamma camera from one side of the phantom. Imaging of prompt x-rays was conducted by the developed x-ray camera from the other side. Induced positrons were measured by the developed dual-head PET system set on the upper and lower sides of the phantom. Main results. With the proposed triple-imaging-modality system, we could simultaneously image the prompt gamma photons and prompt x-rays during proton beam irradiation. Induced positron distributions could be measured after the irradiation by the PET system and the gamma camera. Among these imaging modalities, image quality was the best for the induced positrons measured by PET. The estimated ranges were actually similar to those imaged with prompt gamma photons, prompt x-rays and induced positrons measured by PET. Significance. The developed triple-imaging-modality system made possible to simultaneously measure the three different beam images. The system will contribute to increasing the data available for imaging in therapy and will contribute to better estimating the shapes or ranges of proton beam.

DOI

Scopus
Multi-pixel photon counter-based gamma camera with pinhole collimator to locate Cs-137 sources at high dose rates for the Fukushima nuclear power plant

T. Tomoda, M. Arimoto, T. Mizuno, D. Sato, F. Lucyana, J. Kataoka, M. Kato, J. Ishii, T. Sawano, D. Yonetoku, S. Terazawa, S. Shiota

Journal of Instrumentation 19 ( 2 ) 2024年02月

　概要を見る

The Fukushima Daiichi Nuclear Power Plant was severely damaged during the 2011 Great East Japan Earthquake. However, the ongoing decommissioning work has been limited by the complexity of the reactor’s internal structure and very high radiation levels; locating radioactive sources is essential for efficient decommissioning. Conventional gamma cameras are mainly designed for low radiation dose (∼mSv/h) and using them under high radiation conditions is difficult (>Sv/h). Therefore, we developed a pinhole gamma camera with a gamma radiation detector consisting of a high-speed YGAG scintillator array and multi-pixel photon counters to locate radioactive sources at high dose rates. The gamma-ray photon signals captured by the developed two-dimensional detector array can be processed at a speed as high as >1 MHz/pixel using the developed large scale integrated circuit. Herein, we report the measurement results of an extremely high radioactivity of137Cs (∼34 TBq) using the developed gamma camera. The gamma-ray source position was determined using an angular size of ∼4.6◦, with images obtained at 2 m from the radioactive source and at a dose rate of 0.3 Sv/h. The direct gamma rays with a photoelectric peak at 662 keV and scattered component of gamma rays can be distinguished from the measured spectrum. We also characterize the imaging capability of the137Cs depending on the detected gamma-ray energies and discuss related details.

DOI

Scopus
Sparse-view image reconstruction with total-variation minimization applied to sparsely sampled projection data from SiPM-based photon-counting CT

D. Sato, M. Arimoto, J. Kotoku, H. Kawashima, S. Kobayashi, K. Okumura, K. Murakami, F. Lucyana, T. Tomoda, J. Kataoka, M. Sagisaka, S. Terazawa, S. Shiota

Journal of Instrumentation 19 ( 02 ) C02010 - C02010 2024年02月 [査読有り]

　概要を見る

Abstract

We constructed a sparse-view computed tomography (CT) system that combines a compressed sensing (CS)-based image-reconstruction algorithm and SiPM-based photon-counting (PC) CT. CS-based image-reconstruction algorithms have been extensively studied for X-ray CT image reconstruction using fewer projections because they are expected to reduce CT imaging time and radiation exposure while maintaining CT image quality. In most previous studies, CS-based image-reconstruction algorithms have been applied to data obtained through numerical simulations or conventional dual-energy CT. However, studies on PC-CT have been scarce. Therefore, we applied a CS-based image-reconstruction algorithm to the projection data obtained using our previously established SiPM-based PC-CT system and evaluated its image quality. We prepared static phantoms equivalent to iodine-containing contrast agents and a mouse model injected with iodine-containing contrast agents as subjects. Thereafter, CT scanning was performed. The obtained projection data were downsampled to simulate a sparse-view situation, and a CS-based image-reconstruction algorithm with total-variation minimization was applied. Consequently, sparse-view CT images were successfully reconstructed, and the image quality was maintained even after downsampling the projection data (downsampling ratios of 1/10 and 1/2 for the rod phantom and mouse model, respectively). Thus, the imaging time and exposure dose could be remarkably reduced (by a factor of 10 or 2), indicating that the CS-based image-reconstruction algorithm is effective for PC-CT.

DOI
Range and light output measurements of trajectory images in a GAGG plate with different alpha particle energies

Seiichi Yamamoto, Masao Yoshino, Kohei Nakanishi, Kei Kamada, Akira Yoshikawa, Jun Kataoka

Journal of Instrumentation 19 ( 01 ) P01010 - P01010 2024年01月

　概要を見る

Abstract

An imaging method that utilizes a scintillator plate combined with a magnifying unit and a cooled electron multiplying charge-coupled device (EM-CCD) camera shows promise for obtaining high-resolution trajectory images. However, it is not yet clear whether the ranges of the trajectory images change with the energy of the alpha particles. Additionally, it remains unclear whether the intensity of the trajectory images is affected by the energy of the alpha particles. To address these questions in our trajectory imaging research, we conducted experiments to capture trajectory images of alpha particles with varying energy levels. To generate alpha particles with different energies, we modulated the energy using an americium-241 (Am-241) source covered with varying numbers of Mylar films. With this alpha source and imaging system, we successfully captured trajectory images with different alpha particle energies and were able to assess the ranges and intensities of these trajectories at various energy levels. The estimated ranges from the measured images with different alpha particle energies closely matched the results obtained through simulations. However, it's worth noting that the light output, as evaluated for the measured trajectory images, was slightly lower than the simulated results at lower energy levels probably due to the non-proportionality of the GAGG plate with respect to alpha particle energies.

DOI
A large field-of-view angled panel detector for the development of a plant PET system

Seiichi Yamamoto, Hiroshi Watabe, Mitsutaka Yamaguchi, Nobuo Suzui, Naoki Kawachi, Jun Kataoka

Journal of Instrumentation 19 ( 1 ) T01002 2024年01月 [査読有り]

　概要を見る

<jats:title>Abstract</jats:title>
<jats:p>In plant research, positron emission tomography (PET) is
sometimes employed for physiological studies of plants. However, due
to the generally high cost of PET systems, their application in
plant research centers can be challenging. Furthermore, the
configurations of commercial PET systems might not always align well
with the requirements of plant research. To address these issues, we
have taken the initial steps towards a solution by developing a
large field-of-view (LFOV) angled panel detector intended for the
development of a plant PET system. This panel detector is composed
of two gadolinium orthosilicate (GSO) scintillator blocks, an angled
light guide, and four flat panel photomultiplier tubes
(FP-PMTs). The GSO pixel size used in the scintillator block
measures
2.65 mm (radial)× 2.85 mm (axial)×
15.0 mm, arranged in a configuration of
16 (radial)× 32 (axial) to form a scintillator
block with overall dimensions of
44.0 mm (radial)× 94.4 mm (axial)×
15 mm (depth). By implementing an angled light guide, the
two scintillator blocks were positioned at a 22.5-degree angle,
resulting in the creation of a LFOV angled panel detector. This
specific angle allowed for the arrangement of 16 scintillator blocks
in a hexadecagonal shape using 8 panel detectors when arranged in a
circular configuration. We successfully constructed a panel detector
with an approximate field-of-view of 10 cm× 10 cm
and conducted a comprehensive performance evaluation. Upon
irradiating the panel detector with 511 keV gamma photons, nearly
all 1024 GSO pixels were accurately resolved in the position
histogram, displaying minimal distortion, and exhibiting an average
peak-to-valley ratio of 5.0. Additionally, the energy resolution
achieved was 14% full width at half maximum (FWHM). The resulting
LFOV angled panel detector holds considerable promise for the use
within a cost-effective, user-friendly as well as high performance
plant PET system.</jats:p>

DOI
Optimization of a YAP(Ce) prompt X-ray camera for imaging with spot scanning proton beams at clinical dose levels

Seiichi Yamamoto, Tomohiro Yamashita, Yusuke Kobashi, Takuya Yabe, Takashi Akagi, Mitsutaka Yamaguchi, Naoki Kawachi, Kei Kamada, Akira Yoshikawa, Jun Kataoka

Journal of Instrumentation 18 ( 12 ) 2023年12月

　概要を見る

Prompt secondary electron bremsstrahlung X-ray (prompt X-ray) imaging using a low-energy X-ray camera is a promising method for observing the beam shape from outside a subject. However, it has sometimes been necessary to conduct such imaging at a higher dose than the clinical level to acquire images with acceptable quality. To solve this problem, we optimized a prompt X-ray imaging system to use for spot scanning proton therapy system. The new camera had more than one order higher sensitivity to image several types of beams, including those at the clinical dose level. The optimized prompt X-ray imaging system uses a 4 mm diameter pinhole collimator to increase sensitivity, and it is combined with a larger YAP(Ce) scintillator to increase the magnification ratio and thus improve spatial resolution. We used a list-mode data-acquisition system with high count rate capability. Prompt X-ray images were acquired by irradiating a water phantom with proton beams from the spot scanning proton therapy system. Measurements were taken for pencil beams, spread-out Bragg peak (SOBP) beams, and a beam utilized in actual clinical therapy. For all of the beams, we could measure scanning spot images within a spill and evaluate the ranges for the accumulated images at the clinical dose level. From the list-mode data, we measured the temporarily altered positions of the scanning beams as well as the accumulations of the prompt X-ray images. The optimized prompt X-ray imaging system could improve sensitivity while maintaining better spatial resolution. The new system realized prompt X-ray imaging at the clinical dose level and holds promise for future clinical imaging of prompt X-rays.

DOI

Scopus
A comparative study of EM-CCD and CMOS cameras for particle ion trajectory imaging

Seiichi Yamamoto, Masao Yoshino, Kohei Nakanishi, Katsunori Yogo, Kei Kamada, Akira Yoshikawa, Jun Kataoka

Applied Radiation and Isotopes 111143 - 111143 2023年12月

DOI

Scopus

1

被引用数

(Scopus)
The Third Fermi Large Area Telescope Catalog of Gamma-Ray Pulsars

D. A. Smith, S. Abdollahi, M. Ajello, M. Bailes, L. Baldini, J. Ballet, M. G. Baring, C. Bassa, J. Becerra Gonzalez, R. Bellazzini, A. Berretta, B. Bhattacharyya, E. Bissaldi, R. Bonino, E. Bottacini, J. Bregeon, P. Bruel, M. Burgay, T. H. Burnett, R. A. Cameron, F. Camilo, R. Caputo, P. A. Caraveo, E. Cavazzuti, G. Chiaro, S. Ciprini, C. J. Clark, I. Cognard, A. Corongiu, P. Cristarella Orestano, M. Crnogorcevic, A. Cuoco, S. Cutini, F. D’Ammando, A. de Angelis, M. E. DeCesar, S. De Gaetano, R. de Menezes, J. Deneva, F. de Palma, N. Di Lalla, F. Dirirsa, L. Di Venere, A. Domínguez, D. Dumora, S. J. Fegan, E. C. Ferrara, A. Fiori, H. Fleischhack, C. Flynn, A. Franckowiak, P. C. C. Freire, Y. Fukazawa, P. Fusco, G. Galanti, V. Gammaldi, F. Gargano, D. Gasparrini, F. Giacchino, N. Giglietto, F. Giordano, M. Giroletti, D. Green, I. A. Grenier, L. Guillemot, S. Guiriec, M. Gustafsson, A. K. Harding, E. Hays, J. W. Hewitt, D. Horan, X. Hou, F. Jankowski, R. P. Johnson, T. J. Johnson, S. Johnston, J. Kataoka, M. J. Keith, M. Kerr, M. Kramer, M. Kuss, L. Latronico, S.-H. Lee, D. Li, J. Li, B. Limyansky, F. Longo, F. Loparco, L. Lorusso, M. N. Lovellette, M. Lower, P. Lubrano, A. G. Lyne, Y. Maan, S. Maldera, R. N. Manchester, A. Manfreda, M. Marelli, G. Martí-Devesa, M. N. Mazziotta, J. E. McEnery, I. Mereu, P. F. Michelson, M. Mickaliger, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, M. E. Monzani, A. Morselli, M. Negro, R. Nemmen, L. Nieder, E. Nuss, N. Omodei, M. Orienti, E. Orlando, J. F. Ormes, M. Palatiello, D. Paneque, G. Panzarini, A. Parthasarathy, M. Persic, M. Pesce-Rollins, R. Pillera, H. Poon, T. A. Porter, A. Possenti, G. Principe, S. Rainò, R. Rando, S. M. Ransom, P. S. Ray, M. Razzano, S. Razzaque, A. Reimer, O. Reimer, N. Renault-Tinacci, R. W. Romani, M. Sánchez-Conde, P. M. Saz Parkinson, L. Scotton, D. Serini, C. Sgrò, R. Shannon, V. Sharma, Z. Shen, E. J. Siskind, G. Spandre, P. Spinelli, B. W. Stappers, T. E. Stephens, D. J. Suson, S. Tabassum, H. Tajima, D. Tak, G. Theureau, D. J. Thompson, O. Tibolla, D. F. Torres, J. Valverde, C. Venter, Z. Wadiasingh, N. Wang, N. Wang, P. Wang, P. Weltevrede, K. Wood, J. Yan, G. Zaharijas, C. Zhang, W. Zhu

The Astrophysical Journal 958 ( 2 ) 191 - 191 2023年11月

　概要を見る

Abstract

We present 294 pulsars found in GeV data from the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope. Another 33 millisecond pulsars (MSPs) discovered in deep radio searches of LAT sources will likely reveal pulsations once phase-connected rotation ephemerides are achieved. A further dozen optical and/or X-ray binary systems colocated with LAT sources also likely harbor gamma-ray MSPs. This catalog thus reports roughly 340 gamma-ray pulsars and candidates, 10% of all known pulsars, compared to ≤11 known before Fermi. Half of the gamma-ray pulsars are young. Of these, the half that are undetected in radio have a broader Galactic latitude distribution than the young radio-loud pulsars. The others are MSPs, with six undetected in radio. Overall, ≥236 are bright enough above 50 MeV to fit the pulse profile, the energy spectrum, or both. For the common two-peaked profiles, the gamma-ray peak closest to the magnetic pole crossing generally has a softer spectrum. The spectral energy distributions tend to narrow as the spindown power $\dot{E}$ decreases to its observed minimum near 10³³ erg s⁻¹, approaching the shape for synchrotron radiation from monoenergetic electrons. We calculate gamma-ray luminosities when distances are available. Our all-sky gamma-ray sensitivity map is useful for population syntheses. The electronic catalog version provides gamma-ray pulsar ephemerides, properties, and fit results to guide and be compared with modeling results.

DOI

Scopus

44

被引用数

(Scopus)
Estimating blurless and noise-free Ir-192 source images from gamma camera images for high-dose-rate brachytherapy using a deep-learning approach

Kohei Nakanishi, Seiichi Yamamoto, Takuya Yabe, Katsunori Yogo, Yumiko Noguchi, Kuniyasu Okudaira, Naoki Kawachi, Jun Kataoka

Biomedical Physics & Engineering Express 2023年11月

　概要を見る

Abstract

Objective: Precise monitoring of the position and dwell time of iridium-192 (Ir-192) during high-dose-rate (HDR) brachytherapy is crucial to avoid serious damage to normal tissues. Source imaging using a compact gamma camera is a potential approach for monitoring. However, images from the gamma camera are affected by blurring and statistical noise, which impact the accuracy of source position monitoring. This study aimed to develop a deep-learning approach for estimating ideal source images that reduce the effect of blurring and statistical noise from experimental images captured using a compact gamma camera.&#xD;Approach: A double pix2pix model was trained using the simulated gamma camera images of an Ir-192 source. The first model was responsible for denoising the Ir-192 images, whereas the second model performed super resolution. Trained models were then applied to the experimental images to estimate the ideal images. &#xD;Main results: At a distance of 100 mm between the compact gamma camera and the Ir-192 source, the difference in full width at half maximum (FWHM) between the estimated and actual source sizes was approximately 0.5 mm for a measurement time of 1.5 s. This difference has been improved from approximately 2.7 mm without the use of DL. Even with a measurement time of 0.1 s, the ideal images could be estimated as accurately as in the 1.5 s measurements. This method consistently achieved accurate estimations of the source images at any position within the field of view; however, the difference increased with the distance between the Ir-192 source and the compact gamma camera.&#xD;Significance: The proposed method successfully provided estimated images from the experimental images within errors smaller than 0.5 mm at 100 mm. This method is promising for reducing blurring and statistical noise from the experimental images, enabling precise real-time monitoring of Ir-192 sources during HDR brachytherapy.

DOI

Scopus

2

被引用数

(Scopus)
Direct Measurement of the Spectral Structure of Cosmic-Ray <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mtext>Electrons</mml:mtext><mml:mo>+</mml:mo><mml:mtext>Positrons</mml:mtext></mml:mrow></mml:math> in the TeV Region with CALET on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, E. Berti, G. Bigongiari, W. R. Binns, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, G. A. de Nolfo, K. Ebisawa, A. W. Ficklin, H. Fuke, S. Gonzi, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, F. Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, W. V. Zober

Physical Review Letters 131 ( 19 ) 2023年11月

DOI
Development of an event-by-event based Li–ZnS(Ag) neutron imaging detector with selective neutron detection capability

Seiichi Yamamoto, Masao Yoshino, Kohei Nakanishi, Kei Kamada, Akira Yoshikawa, Hiroki Tanaka, Jun Kataoka

Applied Radiation and Isotopes 111084 - 111084 2023年10月

DOI

Scopus
Sub-micrometer real-time imaging of trajectory of alpha particles using GAGG plate and CMOS camera

Seiichi Yamamoto, Masao Yoshino, Kohei Nakanishi, Katsunori Yogo, Kei Kamada, Akira Yoshikawa, Nanase Koshikawa, Jun Kataoka

Journal of Instrumentation 18 ( 10 ) T10003 - T10003 2023年10月

　概要を見る

Abstract

High-resolution and real-time imaging of the trajectories of alpha particles is desired in nuclear medicine and nuclear engineering. Although an imaging method using a scintillator plate combined with a magnifying unit and a cooled electron multiplying charge-coupled device (EM-CCD) camera is a possible method of obtaining high-resolution trajectory images, the spatial resolution of the system is limited to ∼2 μm. To overcome the spatial resolution limitations of this method on trajectory imaging, we used a cooled complementally metal oxide (CMOS) camera in which the sensor had a much larger number of pixels, which were also smaller. Using the CMOS camera based imaging system, we could measure the trajectories of alpha particles in real time with the spatial resolution of 0.34 μm FWHM. With smoothing of the images to reduce image noise, spatial resolution was still kept to less than 0.75 μm. We conclude that this CMOS camera-based alpha-particle trajectory-imaging system is promising for alpha-particle or other particles imaging where ultrahigh spatial resolution is required.

DOI
Ultrahigh resolution real-time trajectory imaging of neutron induced particles in a scintillator from lithium-6 plate

Yamamoto Seiichi, Yoshino Masao, Nakanishi Kohei, Kamada Kei, Yoshikawa Akira, Kataoka Jun

Journal of Instrumentation 18 ( 10 ) T10002 - T10002 2023年10月

　概要を見る

Abstract

It is known that a lithium-6 (⁶Li) absorbs a neutron and is divided into a triton and an alpha particle. However, the trajectories of the produced tritons have not yet been imaged in real time and high resolution. We developed an ultrahigh-resolution imaging system that can clearly observe the trajectories of neutron induced particles in real time. The developed system is based on a magnifying unit and a cooled electron multiplying charge-coupled device (EM-CCD) camera combined with a ⁶Li plate and a Ce-doped Gd₃Al₂Ga₃O₁₂(GAGG) scintillator plate. Neutrons from a californium-252 (²⁵²Cf) source were irradiated to the ⁶Li plate, which produced tritons and alpha particles. The produced tritons or alpha particles entered the GAGG plate and produced scintillation light along the trajectories. The scintillation trajectories were magnified by the unit, light intensified, and imaged by the EM-CCD camera. Using our system, we could measure the elongated trajectory images of the particles in real time. Most of these trajectories had Bragg peak like shapes in the images. The average range was 15 μm and the width was 4.6 μm FWHM. From the ranges we estimated, we found that these trajectories could be attributed to the induced tritons. Consequently, the developed real time imaging system is promising for research on the ultrahigh resolution imaging of neutron produced particles.

DOI
Erratum: Charge-Sign Dependent Cosmic-Ray Modulation Observed with the Calorimetric Electron Telescope on the International Space Station [Phys. Rev. Lett. 130, 211001 (2023)

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, E. Berti, G. Bigongiari, W. R. Binns, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, G. A. de Nolfo, K. Ebisawa, A. W. Ficklin, H. Fuke, S. Gonzi, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, F. Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, W. V. Zober

Physical review letters 131 ( 10 ) 109902 2023年09月

　概要を見る

This corrects the article DOI: 10.1103/PhysRevLett.130.211001.

DOI PubMed

Scopus
The cosmic-ray electron and positron spectrum measured with CALET on the International Space Station

Yosui Akaike, Oscar Adriani, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年08月

DOI
Results from CALorimetric Electron Telescope (CALET) Observations of Gamma-rays on the International Space Station

Masaki Mori, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年08月

DOI
Optimization of the proton background rejection in the measurement of the electron flux at high energies with CALET on the International Space Station

Sandro Gonzi, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年08月

DOI
Results of the Ultra-Heavy Cosmic-Ray Analysis with CALET on the International Space Station

Wolfgang V Zober, Brian Flint Rauch, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年08月

DOI
Feasibility study on an analysis of CR helium flux with the CALET detector based on an extended acceptance

Marco Mattiazzi, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年08月

DOI
Dark Matter Limits from the CALET Electron+Positron Spectrum with Individual Astrophysical Source Background

Holger Motz, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年08月

DOI
Interpretation of the CALET Electron+Positron Spectrum by Astrophysical Sources

Holger Motz, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年08月

DOI
Cosmic-Ray Modulation during Solar Cycles 24-25 Transition Observed with CALET on the International Space Station

Shoko Miyake, Oscar Adriani, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober, Kazuoki Munakata, Yosui Akaike

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年08月

DOI
Observation of spectral structures in the flux of cosmic ray protons with CALET on the International Space Station

Kazuyoshi Kobayashi, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年08月

DOI
CALET Search for electromagnetic counterparts of gravitational waves in O4

Yuta Kawakubo, Michael L. Cherry, Takanori Sakamoto, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年08月

DOI
Flux ratios of primary elements measured by CALET on the International Space Station

Caterina Checchia, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年08月

DOI
Iron and Nickel fluxes measured by CALET on the International Space Station

Francesco Stolzi, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年08月

DOI
Luminescence imaging of water irradiated by protons under FLASH radiation therapy conditions.

Katsunori Yogo, Satoshi Kodaira, Tamon Kusumoto, Hisashi Kitamura, Toshiyuki Toshito, Hiromitsu Iwata, Masumi Umezawa, Masashi Yamada, Takuto Miyoshi, Masataka Komori, Hiroshi Yasuda, Jun Kataoka, Seiichi Yamamoto

Physics in medicine and biology 68 ( 15 ) 2023年07月 [査読有り] [国際誌]

　概要を見る

Objective.FLASH radiation therapy with ultrahigh dose rates (UHDR) has the potential to reduce damage to normal tissue while maintaining anti-tumor efficacy. However, rapid and precise dose distribution measurements remain difficult for FLASH radiation therapy with proton beams. To solve this problem, we performed luminescence imaging of water following irradiation by a UHDR proton beam captured using a charge-coupled device camera.Approach. We used 60 MeV proton beams with dose rates of 0.03-837 Gy s-1from a cyclotron. Therapeutic 139.3 MeV proton beams with dose rates of 0.45-4320 Gy s-1delivered by a synchrotron-based proton therapy system were also tested. The luminescent light intensity induced by the UHDR beams was compared with that produced by conventional beams to compare the dose rate dependency of the light intensity and its profile.Main results. Luminescence images of water were clearly visualized under UHDR conditions, with significantly shorter exposure times than those with conventional beams. The light intensity was linearly proportional to the delivered dose, which is similar to that of conventional beams. No significant dose-rate dependency was observed for 0.03-837 Gy s-1. The light-intensity profiles of the UHDR beams agreed with those of conventional beams. The results did not differ between accelerators (synchrotron or cyclotron) and beam energies.Significance. Luminescence imaging of water is achievable with UHDR proton beams as well as with conventional beams. The proposed method should be suitable for rapid and easy quality assurance investigations for proton FLASH therapy, because it facilitates real-time, filmless measurements of dose distributions, and is useful for rapid feedback.

DOI PubMed

Scopus

3

被引用数

(Scopus)
Refinement of the High-Energy Gamma-ray Selection for CALET on the International Space Station

Nicholas W Cannady, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年07月

DOI
Statistical analysis into the drivers behind relativistic electron precipitation events observed by CALET on the International Space Station

Anthony Ficklin, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年07月

DOI
Status of the operations of CALET for 7.5 years on the International Space Station

Tadahisa Tamura, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年07月

DOI
Observational Challenges on the ISS: A Case Study with CALET

Nicholas W Cannady, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年07月

DOI
Event-by-Event Analysis for TeV Electron Candidates with CALET on the International Space Station

Nicholas W Cannady, Yosui Akaike, Shoji Torii, Oscar Adriani, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年07月

DOI
Boron flux in cosmic rays and its flux ratio to primary species measured with CALET on the International Space Station

Paolo Maestro, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年07月

DOI
Measurement of iron cosmic-ray primaries below 10 GeV/n by use of the geomagnetic effect with CALET

Masakatsu Ichimura, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Paolo Brogi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年07月

DOI
Helium flux and its ratio to proton flux in cosmic rays measured with CALET on the International Space Station

Paolo Brogi, Oscar Adriani, Yosui Akaike, Katsuaki Asano, Yoichi Aaoka, Eugenio Berti, Gabriele Bigongiari, Walter Robert Binns, Massimo Bongi, Alessandro Bruno, Nicholas Wade Cannady, Guide Castellini, Caterina Checchia, Walter Robert Cherry, Gianmaria Collazuol, Georgia A. de Nolfo, Ken Ebisawa, Anthony W. Ficklin, Hideyuki Fuke, Sandro Gonzi, T. Gregory Guzik, Thomas Hams, Kinya Hibino, Masakatsu Ichimura, Kunihito Ioka, Wataru Ishizaki, Martin H. Israel, Katsumasa Kasahara, Jun Kataoka, Ryuho Kataoka, Yusaku Katayose, Chihiro Kato, Norita Kawanaka, Yuta Kawakubo, Kenko Kobayashi, Kazunori Kohri, Henric S. Krawczynski, John F. Krizmanic, Paolo Maestro, Pier Simone Marrocchesi, Alberto Maria Messineo, Jason W. Mitchell, Shoko Miyake, Alexander Moiseev, Masaki Mori, Nicola Mori, Holger Martin Motz, Kazuoki Munakata, Satoshi Nakahira, Jun Nishimura, Shoji Okuno, Jonathan Ormes, Shunsuke OZAWA, Lorenzo Pacini, Paolo Pacini, Brian Flint Rauch, Ricciarini Ricciarini, Kazuhiro Sakai, Takanori Sakamoto, Makoto Sasaki, Yuki Shimizu, Atsushi Shiomi, Piero Spillantini, Francesco Stolzi, Satoshi Sugita, Arta Sulaj, Masato Takita, Tadahisa Tamura, Toshio Terasawa, Shoji Torii, Yoshiki Tsunesada, Yukio Uchihori, Elena Vannuccini, John P. Wefel, Kazutaka Yamaoka, Shohei Yanagita, Atsumasa Yoshida, Kenji Yoshida, Wolfgang V Zober

Proceedings of 38th International Cosmic Ray Conference — PoS(ICRC2023) 2023年07月

DOI
Citizen Science Observation of a Gamma‐Ray Glow Associated With the Initiation of a Lightning Flash

M. Tsurumi, T. Enoto, Y. Ikkatai, T. Wu, D. Wang, T. Shinoda, K. Nakazawa, N. Tsuji, G. S. Diniz, J. Kataoka, N. Koshikawa, R. Iwashita, M. Kamogawa, T. Takagaki, S. Miyake, D. Tomioka, T. Morimoto, Y. Nakamura, H. Tsuchiya

Geophysical Research Letters 50 ( 13 ) 2023年07月

DOI
Simultaneous imaging of luminescence and prompt x-rays during irradiation with spot-scanning proton beams at clinical dose level.

Seiichi Yamamoto, Tomohiro Yamashita, Yusuke Kobashi, Takuya Yabe, Takashi Akagi, Mitsutaka Yamaguchi, Naoki Kawachi, Kei Kamada, Akira Yoshikawa, Jun Kataoka

Biomedical physics & engineering express 9 ( 4 ) 2023年06月 [国際誌]

　概要を見る

Prompt x-ray imaging is a promising method for observing the beam shape from outside a subject. However, its distribution is different from dose distribution, and thus a comparison with the dose is required. Meanwhile, luminescence imaging of water is a possible method for imaging the dose distribution. Consequently, we performed simultaneous imaging of luminescence and prompt x-rays during irradiation by proton beams to compare the distributions between these two different imaging methods. Optical imaging of water was conducted with spot-scanning proton beams at clinical dose level during irradiation to a fluorescein (FS) water phantom set in a black box. Prompt x-ray imaging was also conducted simultaneously from outside the black box using a developed x-ray camera during proton beam irradiation to the phantom. We measured images of the luminescence of FS water and prompt x-rays for various types of proton beams, including pencil beams, spread-out Bragg peak (SOBP) beams, and clinically used therapy beams. After the imaging, ranges were estimated from FS water and prompt x-rays and compared with those calculated with a treatment planning system (TPS). We could measure the prompt x-ray and FS water images simultaneously for all types of proton beams. The ranges estimated from the FS water and those calculated with the TPS closely matched, within a difference of several mm. Similar range difference was found between the results estimated from prompt x-ray images and those calculated with the TPS. We confirmed that the simultaneous imaging of luminescence and prompt x-rays were possible during irradiation with spot-scanning proton beams at a clinical dose level. This method can be applied to range estimation as well as comparison with the dose for prompt x-ray imaging or other imaging methods used in therapy with various types of proton beams at a clinical dose level.

DOI PubMed

Scopus
A high-resolution real-time imaging system for observing the trajectories of neutron induced particles in a scintillator

Seiichi Yamamoto, Masao Yoshino, Kohei Nakanishi, Kei Kamada, Akira Yoshikawa, Jun Kataoka

Journal of Instrumentation 18 ( 06 ) T06009 - T06009 2023年06月

　概要を見る

Abstract

High-resolution imaging of neutron induced particles is required in such methods as neutron radiography. However, the scintillation spots in a neutron-sensitive scintillator have not yet been imaged nor measured for size. We developed a high-resolution, real-time neutron induced particle imaging system for observing these particles' trajectories in a scintillator. The developed system is based on a magnifying unit and a cooled electron multiplying charge-coupled device (EM-CCD) camera combined with a lithium-containing silver-doped zinc sulfide (Li-ZnS(Ag)) scintillator plate. Neutrons from a californium-252 (²⁵²Cf) source were irradiated to the Li-ZnS(Ag) scintillator and imaged with the system. Using our system, we measured the scintillation spots of the neutron induced particles having different shapes in real time. In some of these measured scintillation spots, those with elliptical shapes were observed due to the trajectories of the particles in the scintillator. The spatial resolution calculated from the widths of the scintillation spots was ∼56 μm. Consequently, the developed imaging system is promising for research on neutron imaging that requires high spatial resolution.

DOI
Hybrid imaging of prompt x-rays and induced positrons using a pinhole gamma camera during and after irradiation of protons.

Seiichi Yamamoto, Hiroshi Watabe, Kohei Nakanishi, Takuya Yabe, Mitsutaka Yamaguchi, Naoki Kawachi, Kei Kamada, Akira Yoshikawa, Md Rafiqul Islam, Masayasu Miyake, Kazuo S Tanaka, Jun Kataoka

Physics in medicine and biology 68 ( 11 ) 2023年05月 [国際誌]

　概要を見る

Objective. Prompt x-ray imaging using a low-energy x-ray camera is a promising method for observing a proton beam's shape from outside the subject. Furthermore, imaging of positrons produced by nuclear reactions with protons is a possible method for observing the beam shape. However, it has not been possible to measure these two types of images with a single imaging system due to the limited imaging capability of existing systems. Imaging of both prompt x-rays and the distribution of positrons may compensate for the shortcomings of each method.Approach. We conducted imaging of the prompt x-ray using a pinhole x-ray camera during irradiation with protons in list mode. Then, after irradiation with protons, imaging of annihilation radiations from the produced positrons was conducted using the same pinhole x-ray camera in list mode. After this imaging, list-mode data were sorted to obtain prompt x-ray images and positron images.Main results. With the proposed procedure, we could measure both prompt x-ray images and induced positron images with a single irradiation by a proton beam. From the prompt x-ray images, ranges and widths of the proton beams could be estimated. The distributions of positrons were slightly wider than those of the prompt x-rays. From the time sequential positron images, we could derive the time activity curves of the produced positrons.Significance. Hybrid imaging of prompt x-rays and induced positrons using a pinhole x-ray camera was achieved. The proposed procedure would be useful for measuring prompt x-ray images during irradiation to estimate the beam structures as well as for measuring the induced positron images after irradiation to estimate the distributions and time activity curves of the induced positrons.

DOI PubMed

Scopus

1

被引用数

(Scopus)
Charge-Sign Dependent Cosmic-Ray Modulation Observed with the Calorimetric Electron Telescope on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, E. Berti, G. Bigongiari, W. R. Binns, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, G. A. de Nolfo, K. Ebisawa, A. W. Ficklin, H. Fuke, S. Gonzi, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, F. Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, W. V. Zober

Physical Review Letters 130 ( 21 ) 2023年05月

DOI
Direct Measurement of the Cosmic-Ray Helium Spectrum from 40 GeV to 250 TeV with the Calorimetric Electron Telescope on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, E. Berti, G. Bigongiari, W. R. Binns, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, G. A. de Nolfo, K. Ebisawa, A. W. Ficklin, H. Fuke, S. Gonzi, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, F. Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, W. V. Zober

Physical Review Letters 130 ( 17 ) 2023年04月

DOI
Development of an ultrahigh resolution real time alpha particle imaging system for observing the trajectories of alpha particles in a scintillator

Seiichi Yamamoto, Masao Yoshino, Kei Kamada, Ryuga Yajima, Akira Yoshikawa, Kohei Nakanishi, Jun Kataoka

Scientific Reports 13 ( 1 ) 2023年04月 [査読有り]

　概要を見る

Abstract

High-resolution imaging of alpha particles is required in the detection of alpha radionuclides in cells or small organs for the development of radio-compounds for targeted alpha-particle therapy or other purposes. We developed an ultrahigh resolution, real time alpha-particle imaging system for observing the trajectories of alpha particles in a scintillator. The developed system is based on a magnifying unit and a cooled electron multiplying charge-coupled device (EM-CCD) camera, combined with a 100-µm-thick Ce-doped Gd₃Al₂Ga₃O₁₂ (GAGG) scintillator plate. Alpha particles from an Am-241 source were irradiated to the GAGG scintillator and imaged with the system. Using our system, we measured the trajectories of the alpha particles having different shapes in real time. In some of these measured trajectories, the line shapes of the alpha particles that flew in the GAGG scintillator were clearly observed. The lateral profiles of the alpha-particle trajectories were imaged with widths of ~ 2 µm. We conclude that the developed imaging system is promising for research on targeted alpha-particle therapy or other alpha particle detections that require high spatial resolution.

DOI

Scopus

6

被引用数

(Scopus)
Prompt X-ray imaging during irradiation with spread-out Bragg peak (SOBP) beams of carbon ions.

Seiichi Yamamoto, Takuya Yabe, Takashi Akagi, Mitsutaka Yamaguchi, Naoki Kawachi, Kei Kamada, Akira Yoshikawa, Jun Kataoka

Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB) 109 102592 - 102592 2023年04月 [国際誌]

　概要を見る

Prompt secondary electron bremsstrahlung X-ray (prompt X-ray) imaging using a low-energy X-ray camera is a promising method for observing a beam shape from outside the subject. However, such imaging has so far been conducted only for pencil beams without a multi-leaf collimator (MLC). The use of spread-out Bragg peak (SOBP) with an MLC may increase the scattered prompt gamma photons and decrease the contrast of the images of prompt X-rays. Consequently, we performed prompt X-ray imaging of SOBP beams formed with an MLC. This imaging was carried out in list mode during irradiation of SOBP beams to a water phantom. An X-ray camera with a 1.5-mm diameter as well as 4-mm-diameter pinhole collimators was used for the imaging. List mode data were sorted to obtain the SOBP beam images as well as energy spectra and time count rate curves. Due to the high background counts from the scattered prompt gamma photons penetrating the tungsten shield of the X-ray camera, the SOBP beam shapes were difficult to observe with a 1.5-mm-diameter pinhole collimator. With the 4-mm-diameter pinhole collimators, images of SOBP beam shapes at clinical dose levels could be obtained with the X-ray camera. The use of a 4-mm-diameter pinhole collimator attached to the X-ray camera is effective for prompt X-ray imaging with high sensitivity and low background counts. This approach makes it possible to image SOBP beams with an MLC when the counts are low and the background levels are high.

DOI PubMed

Scopus

3

被引用数

(Scopus)
Development of a list-mode data acquisition system for prompt X-ray imaging during irradiation with carbon-ions

Seiichi Yamamoto, Takuya Yabe, Takashi Akagi, Mitsutaka Yamaguchi, Naoki Kawachi, Kei Kamada, Akira Yoshikawa, Jun Kataoka

Journal of Instrumentation 18 ( 4 ) 2023年04月

　概要を見る

Prompt X-ray imaging using a low-energy X-ray camera is a promising method for observing the beam shape from outside the subject. However, such imaging has so far been conducted only on static images with relatively long acquisition times without any energy information. Consequently, we performed list-mode prompt X-ray imaging using a newly developed data acquisition system combined with a pinhole YAP(Ce) camera during irradiation of a water phantom with carbon ions. Prompt X-ray imaging was conducted in list mode with a 1-ms time stamp and 128-channel energy bins during irradiation of a water phantom with 241.5 MeV/n carbon ions. After the imaging, list-mode data were sorted to obtain the time-sequential prompt X-ray images and those with different energies. From the images with different energies, we found the energy spectra were different depending on the areas in the images, and the reduction of the background fraction was possible. From the short time-sequential prompt X-ray images, we could even observe the differences in the images depending on the acquisition times, as well as the spill and ripple shapes of the carbon ion beam.

DOI

Scopus
Initial results of in vivo CT imaging of contrast agents using MPPC-based photon-counting CT

Daichi Sato, Makoto Arimoto, Kotaro Yoshiura, Tomoya Mizuno, Ko Aiga, Kairi Ishiguro, Takahiro Tomoda, Hiroki Kawashima, Satoshi Kobayashi, Kenichiro Okumura, Kazuhiro Murakami, Jun Kataoka, Takaya Toyoda, Mayu Sagisaka, Shinsuke Terazawa, Satoshi Shiota

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1048 167960 - 167960 2023年03月

DOI

Scopus

7

被引用数

(Scopus)
Development and x-ray imaging performance of Tb-doped GdAlO<inf>3</inf>- α Al<inf>2</inf>O<inf>3</inf>submicron-diameter phase-separated scintillator fibers

M. Yoshino, K. Kamada, S. Yamamoto, R. Yajima, R. Sasaki, M. Sagisaka, J. Kataoka, T. Horiai, Y. Yokota, A. Yoshikawa

AIP Advances 13 ( 2 ) 2023年02月

　概要を見る

Scintillators are key components in high-energy x-ray detectors for x-ray computed tomography, which are applied in medical diagnosis, nondestructive testing, and security inspection. Scintillators in x-ray imaging are required to have both high spatial resolution and sensitivity; however, a trade-off between spatial resolution and sensitivity exists. To improve the sensitivity of a scintillator, its thickness must be increased; however, spatial resolution deteriorates with increasing thickness. Here, we developed a well-aligned Tb-doped GdAlO3-αAl2O3 phase-separated scintillator fiber (PSSF) with a diameter of 1.25-μm by a micro-pulling-down method. The luminescence, scintillation, and imaging performances of a grown PSSF sample were evaluated. X-ray-induced radioluminescence measurements of the sample showed Tb3+ 4f-4f emissions in the wavelength range of 470-700 nm, and the maximum emission peak was at 550 nm. The contrast transfer function at 10 lp/mm was 82% for both 270 and 500 μm-thick PSSF samples. We calculated the luminescence index, which is the product of the scintillator's light yield and sensitivity, of the samples and compared their values with commercially available conventional CsI:Tl columnar scintillators. The Tb-doped GdAlO3-αAl2O3 PSSF exhibits higher contrast transfer function and luminescence index values at above 60 keV x-ray region compared with the tested conventional scintillators.

DOI

Scopus

9

被引用数

(Scopus)
Development of 64-channel LSI with ultrafast analog and digital signal processing dedicated for photon-counting computed tomography with multi-pixel photon counter

Makoto Arimoto, Daichi Sato, Tomoya Mizuno, Kotaro Yoshiura, Kairi Ishiguro, Takahiro Tomoda, Hiroki Kawashima, Satoshi Kobayashi, Jun Kataoka, Mayu Sagisaka, Hirokazu Ikeda, Shinsuke Terazawa, Satoshi Shiota

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1047 2023年02月

　概要を見る

X-ray computed tomography (CT) is non destructive visualization inside the human body. Recently, X-ray photon-counting CT (PC-CT) has drawn attention for reducing the high doses used for patients and acquiring spectral information to identify materials. To enable photon-counting imaging with a wide region (∼60 mm long) of a small animal, we developed a photon-counting system using a 64-channel multi-pixel photon counter (MPPC) array with a fast temporal response (a few nanoseconds) and a very large signal gain (∼106), combined with a 64-channel yttrium–gadolinium–aluminum–gallium garnet scintillator array. In particular, to realize ultra-fast analog and digital signal processing (>10 MHz/channel), we developed a 64-channel large-scale integrated circuit (LSI) named MPPC-CT64. We had previously developed a 16-channel PC-CT system with a 16-channel LSI (MPPC-CT16). Although the MPPC-CT16 realized photon-counting imaging for a ∼16-mm-long phantom, there were some energy uncertainties in the LSI, which degraded the obtained CT image quality. The MPPC-CT64 implements a function for correcting the threshold energies and also increases the number of energy thresholds from four to six, which provides more precise measurements of CT values dependent on X-ray energy. In this paper, we briefly present the electric architecture and performance evaluation of the LSI combined with MPPCs.

DOI

Scopus

6

被引用数

(Scopus)
Development of an MPPC-based gamma-ray detector onboard a radiation source imager under high-dose environments and initial performance results

Tomoya Mizuno, Makoto Arimoto, Daichi Sato, Kotaro Yoshiura, Takahiro Tomoda, Kairi Ishiguro, Jun Kataoka, Tatsuya Sawano, Daisuke Yonetoku, Shinsuke Terazawa, Satoshi Shiota

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1046 2023年01月

　概要を見る

Since the accident at the Fukushima Daiichi Nuclear Power Plant ∼10 years ago, various studies have been conducted focusing on the decontamination of radioactive materials and the decommissioning of the remains of the reactor. It is crucial to identify the locations of radioactive materials for the decontamination of a building that is exposed to high radiation doses. One of the most widely used methods is the visualization of gamma rays with energy information using a photon-counting imager. However, the existing imagers have limited functionality, making it difficult to implement them in such an environment. Therefore, we have developed a novel pinhole gamma imager containing multi-pixel photon counters (MPPCs) combined with fast scintillators, which are processed using fast signal-processing analog and digital large integrated circuits under high-dose environments. The two-dimensional sensor array developed in this study can obtain incident gamma-ray photon energies with a counting rate of a few MHz/mm2. Furthermore, we were able to perform two-dimensional gamma-ray imaging of an extremely strong radiation source of 60Co with ∼45 TBq, by combining the sensor array with the dedicated tungsten collimator and housing.

DOI

Scopus

4

被引用数

(Scopus)
Experimental verification of efficacy of pBCT in terms of physical and biological aspects

Mana Hosobuchi, Jun Kataoka, Hiromu Yokokawa, You Okazaki, Ryoichi Hirayama, Taku Inaniwa, Masashi Ueda, Mitsuhiro Kimura

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1045 167537 2023年01月 [査読有り]

DOI

Scopus

5

被引用数

(Scopus)
Activation imaging: New concept of visualizing drug distribution with wide-band X-ray and gamma-ray imager

N. Koshikawa, A. Omata, M. Masubuchi, J. Kataoka, Y. Kadonaga, K. Tokoi, S. Nakagawa, A. Imada, A. Toyoshima, K. Matsunaga, H. Kato, Y. Wakabayashi, T. Kobayashi, K. Takamiya, M. Ueda

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1045 167599 2023年01月 [査読有り]

DOI

Scopus

2

被引用数

(Scopus)
Experiment of in vivo imaging with third generation setup using Photon-Counting CT with 64ch Multi-Pixel Photon Counter

M. Sagisaka, T. Toyoda, J. Kataoka, M. Arimoto, H. Kawashima, S. Kobayashi, K. Murakami, K. Okumura, D. Sato, K. Yoshiura, T. Mizuno, K. Aiga, S. Terazawa, S. Shiota

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1045 2023年01月

　概要を見る

X-ray computed tomography is one of the commonly used diagnostic imaging technique. However, it has some problems which are lack of energy information and high dose exposure. These problems can be solved by using a next generation CT called Photon Counting CT (PC-CT). PC-CT can acquire multi-color images with significantly low radiation dose. The detector system of the PC-CT we propose consists of Multi-Pixel Photon Counter (MPPC) coupled with a high-speed scintillator thus can be made with lower cost and simpler system. In this study, we propose a novel method of material decomposition using the MPPC based PC-CT. Furthermore, we imaged mice with MPPC based PC-CT system as a first attempt. Iodine and gadolinium mixed contrast agents and gold-nanoparticles (AuNPs) were injected when imaging. In addition, the CT images of mice showed bone, lungs, heart, kidneys, and bladder. As a future prospect, we will work on visualizing the pharmacokinetics in mice.

DOI

Scopus

5

被引用数

(Scopus)
High-precision time study of gamma-ray bursts during thunderstorms

E. Kuriyama, M. Masubuchi, N. Koshikawa, R. Iwashita, A. Omata, T. Kanda, J. Kataoka, M. Tsurumi, G. Diniz, T. Enoto, Y. Wada

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1045 167515 - 167515 2023年01月

DOI

Scopus
Cosmic-ray Boron Flux Measured from 8.4 GeV/n to 3.8 TeV/n with the Calorimetric Electron Telescope on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, E. Berti, G. Bigongiari, W. R. Binns, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, G. A. de Nolfo, K. Ebisawa, A. W. Ficklin, H. Fuke, S. Gonzi, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, F. Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, W. V. Zober

Physical Review Letters 129 ( 25 ) 2022年12月 [査読有り]

　概要を見る

We present the measurement of the energy dependence of the boron flux in cosmic rays and its ratio to the carbon flux in an energy interval from 8.4 GeV/n to 3.8 TeV/n based on the data collected by the Calorimetric Electron Telescope (CALET) during ∼6.4 yr of operation on the International Space Station. An update of the energy spectrum of carbon is also presented with an increase in statistics over our previous measurement. The observed boron flux shows a spectral hardening at the same transition energy E0∼200 GeV/n of the C spectrum, though B and C fluxes have different energy dependences. The spectral index of the B spectrum is found to be γ=-3.047±0.024 in the interval 25<E<200 GeV/n. The B spectrum hardens by ΔγB=0.25±0.12, while the best fit value for the spectral variation of C is ΔγC=0.19±0.03. The B/C flux ratio is compatible with a hardening of 0.09±0.05, though a single power-law energy dependence cannot be ruled out given the current statistical uncertainties. A break in the B/C ratio energy dependence would support the recent AMS-02 observations that secondary cosmic rays exhibit a stronger hardening than primary ones. We also perform a fit to the B/C ratio with a leaky-box model of the cosmic-ray propagation in the Galaxy in order to probe a possible residual value λ0 of the mean escape path length λ at high energy. We find that our B/C data are compatible with a nonzero value of λ0, which can be interpreted as the column density of matter that cosmic rays cross within the acceleration region.

DOI PubMed
Short time sequential luminescence imaging of water during irradiation by protons

Seiichi Yamamoto, Takuya Yabe, Katsunori Yogo, Takashi Akagi, Jun Kataoka

Journal of Instrumentation 17 ( 12 ) 2022年12月

　概要を見る

<jats:title>Abstract</jats:title>
<jats:p>Although luminescence imaging of water during irradiation by particle ions is a promising method for dose estimation, it has only been tried for static images in which temporal information is not included. In addition to the positional distribution of the beam, temporal information is also important because the beams from a synchrotron-based therapy system have short pulse shapes called spills. The temporal information is also important for high dose rate, short-time radiotherapy, or so-called FLASH radiotherapy. To measure the particle ion beam distributions with precise temporal information, we conducted short time sequential luminescence imaging of protons. First, we measured short time sequential luminescence images during irradiation of a water phantom by 150-MeV protons using a cooled charge-coupled device (CCD) camera at 0.143-s intervals. With this imaging, the images showed beam distributions, but the shapes of the spill were not precisely evaluated in time intensity curves due to the insufficient sampling rate of the imaging. Then we measured short time sequential optical images with 0.053-s intervals. With this imaging, the images showed that the beam distributions in the spill shape could be measured, but the image and depth profiles evaluated from the images were noisy due to the insufficient light intensity. Consequently, we measured short time sequential luminescence images during irradiation of fluorescein (FS) water by 150-MeV protons. Since FS water produced ∼10 times higher luminescence, we could obtain high-intensity images enabling us to evaluate the time intensity curves based on the shape of the spills during measurement with 0.053-s intervals. The depth profiles of the beam were also obtained from the measured images. With these results, we confirmed that time sequential luminescence imaging was possible and, in such cases, FS water images measured at 0.053-s intervals are most promising to measure the short time sequential luminescence images during irradiation of protons.</jats:p>

DOI
Multi-modal 3D imaging of radionuclides using multiple hybrid Compton cameras

Akihisa Omata, Miho Masubuchi, Nanase Koshikawa, Jun Kataoka, Hiroki Kato, Atsushi Toyoshima, Takahiro Teramoto, Kazuhiro Ooe, Yuwei Liu, Keiko Matsunaga, Takashi Kamiya, Tadashi Watabe, Eku Shimosegawa, Jun Hatazawa

Scientific Reports 12 ( 1 ) 2022年12月

　概要を見る

<title>Abstract</title>For radiological diagnosis and radionuclide therapy, X-ray and gamma-ray imaging technologies are essential. Single-photon emission tomography (SPECT) and positron emission tomography (PET) play essential roles in radiological diagnosis, such as the early detection of tumors. Radionuclide therapy is also rapidly developing with the use of these modalities. Nevertheless, a limited number of radioactive tracers are imaged owing to the limitations of the imaging devices. In a previous study, we developed a hybrid Compton camera that conducts simultaneous Compton and pinhole imaging within a single system. In this study, we developed a system that simultaneously realizes three modalities: Compton, pinhole, and PET imaging in 3D space using multiple hybrid Compton cameras. We achieved the simultaneous imaging of Cs-137 (Compton mode targeting 662 keV), Na-22 (PET mode targeting 511 keV), and Am-241 (pinhole mode targeting 60 keV) within the same field of view. In addition, the imaging of Ga-67 and In-111, which are used in various diagnostic scenarios, was conducted. We also verified that the 3D distribution of the At-211 tracer inside a mouse could be imaged using the pinhole mode.

DOI

Scopus

13

被引用数

(Scopus)
Activation imaging of drugs with hybrid Compton camera: A proof-of-concept study

N. Koshikawa, A. Omata, M. Masubuchi, Y. Okazaki, J. Kataoka, K. Matsunaga, H. Kato, A. Toyoshima, Y. Wakabayashi, T. Kobayashi

Applied Physics Letters 121 ( 19 ) 193701 - 193701 2022年11月 [査読有り]

　概要を見る

The visualization of drugs is essential for cancer treatment. Although several methods for visualizing drugs have been proposed, a versatile method that can be easily applied to various drugs has not yet been established. Therefore, we propose “activation imaging,” in which a drug is irradiated with thermal neutrons and becomes radioactive, enabling visualization using emitted x rays and/or gamma rays. Activation imaging does not require the conjugation of specific tracers with drugs. Therefore, it can be easily applied to a variety of drugs, drug carriers (e.g., metal nanoparticles), and contrast agents. In this study, neutron activation, gamma-ray spectroscopy, and imaging of drug carriers, anticancer drug, and contrast agents were performed. Gold nanoparticles (AuNPs) and platinum nanoparticles were used as drug carriers, cisplatin was used as an anticancer drug, and gadoteridol and iohexol were used as contrast agents. As a neutron source, the RIKEN accelerator-driven compact neutron source II (RANS-II) was utilized. The imaging was performed using a hybrid Compton camera (HCC). The HCC can visualize x rays and gamma rays ranging from a few keV to nearly 1 MeV, which enables the imaging of various x rays and gamma rays emitted from the activated drugs. As a result, the gamma-ray spectra indicated the generation of radioisotopes through neutron irradiation, and AuNPs and iohexol were visualized.

DOI

Scopus

5

被引用数

(Scopus)
Optimization of the energy window setting in Ir-192 source imaging for high-dose-rate brachytherapy using a YAP(Ce) gamma camera

Jura Nagata, Kohei Nakanishi, Seiichi Yamamoto, Takuya Yabe, Katsunori Yogo, Yumiko Noguchi, Kuniyasu Okudaira, Kei Kamada, Akira Yoshikawa, Jun Kataoka

Physica Medica 103 66 - 73 2022年11月

DOI

Scopus

3

被引用数

(Scopus)
Compton Camera Imaging of a Gamma-Ray Glow From a Thunderstorm

E. Kuriyama, M. Masubuchi, N. Koshikawa, R. Iwashita, A. Omata, T. Kanda, J. Kataoka, M. Tsurumi, G. Diniz, T. Enoto, Y. Wada

Geophysical Research Letters 49 ( 19 ) 2022年10月

　概要を見る

Gamma-ray glows associated with thunderclouds have been observed since the 1980s, however it remains unclear how, and at which thunderstorms gamma-ray glows are generated in dense atmospheres. In this study, we report the first Compton camera imaging of a gamma-ray glow from a winter thundercloud. On 14 January 2022, using two identical Bi4Ge3O12 scintillators in energy range of 0.05–5 MeV, we detected two gamma-ray glows lasting ∼4 min in a mountain area 25 km from the Japan Sea and 410 m above sea level. The same events were also observed by the Compton camera, where the first glow we observed suggested statistically significant (4.0 and 5.9 σ level) signals of two enhanced concentrations in gamma-ray photon images in a range of 0.15–1.5 MeV. These concentrations were most clearly observed in a time window of Δt = 50 s around the peak intensity of the gamma-ray glow.

DOI

Scopus

3

被引用数

(Scopus)
Wide-band X-ray and gamma-ray imaging of living mouse to reveal pharmacokinetics of At-211

M. Masubuchi, A. Omata, N. Koshikawa, J. Kataoka, H. Kato, A. Toyoshima, K. Ooe, D. Katayama, T. Teramoto, K. Matsunaga, T. Kamiya, T. Watabe, E. Shimosegawa, J. Hatazawa

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 167581 - 167581 2022年10月

DOI

Scopus

4

被引用数

(Scopus)
Monte Carlo approach to comparison of parallel-hole collimators of clinical scintillation camera system for imaging astatine-211 (At-211)

Kohei Nakanishi, Seiichi Yamamoto, Jun Kataoka

Journal of Instrumentation 17 ( 10 ) T10007 - T10007 2022年10月

　概要を見る

Abstract

Astatine-211 (At-211) is a promising alpha particle emitter for targeted radionuclide therapy. Since its daughter isotope (polonium-211(Po-211)) emits characteristic X-rays of about 80 keV, the distribution of At-211 in the body can be imaged by detecting the X-rays with a scintillation camera. However, the isotopes also emit high-energy gamma photons that are collimated with difficulty for a parallel-hole collimator of a clinical scintillation camera system, and thus the selection of a collimator is important. In this study, we compared the performances of low-energy high-resolution (LEHR), low-energy all-purpose (LEAP), medium-energy (ME), and high-energy (HE) parallel-hole collimators for At-211 using Monte Carlo simulation. We simulated a clinical scintillation camera system with the collimators using the Geant4 toolkit. The energy spectra, sensitivities, and spatial resolutions for the point source of At-211 were evaluated. Moreover, we simulated imaging of six sphere sources of At-211 in a 1-cm-thick cylindrical phantom filled with At-211 solution to evaluate image contrast. All of the results in this study are simulation data. The spatial resolution with LEHR was 7.6 mm full width at half maximum (FWHM) and the highest between collimators, while the sensitivity with LEAP was 85 cps/MBq and the highest. The image contrast acquired with the ME collimator was superior to those with the other collimators. We concluded that the LEHR, LEAP, and ME collimators had their advantages, so an optimum collimator should be selected depending on the purpose of imaging of At-211, although there was no advantage in using the HE collimator for the imaging of At-211.

DOI
Performance demonstration of a novel photon-counting CT for preclinical application

T. Toyoda, J. Kataoka, M. Sagisaka, M. Arimoto, D. Sato, K. Yoshiura, H. Kawashima, S. Kobayashi, J. Kotoku, S. Terazawa, S. Shiota, M. Ueda

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1040 2022年10月

　概要を見る

Photon-counting computed tomography (PC-CT) has attracted attention over the last few years as the next-generation CT technique that solves the problems encountered in clinical CT. In PC-CT, dark current and electronic noise can be reduced by setting the energy threshold to exceed the noise level, which leads to a low-dose scan. Furthermore, multiple energy thresholds realize multicolor CT imaging, which is not possible with clinical CT. Recently, we proposed a novel PC-CT system consisting of a multipixel photon counter (MPPC) coupled with a high-speed scintillator, performing simultaneous imaging of multiple contrast agents and estimate concentration. However, the PC-CT images obtained by our PC-CT system faces some limitations, such as degradation of image quality due to the lack of photon statistics and/or image resolution loss due to the pixel size of the detectors. In this study, the signal-to-noise ratio (SNR) of the PC-CT images was improved by applying machine-learning models, that is, U-Net and Noise2Noise, to the PC-CT images. In addition, a new imaging method was developed to acquire the high-resolution CT images required for clinical use. As a result, the resolution of the CT images improved from 1.04 mm to 0.77 mm. Finally, the visualization of contrast agents in plants was set as a challenge for the next step towards the clinical application of MPPC-based PC-CT. The results demonstrate that our PC-CT system can provide color imaging not only in phantom-based experiments, but also in plants close to an organism.

DOI

Scopus

2

被引用数

(Scopus)
Short‐time sequential high‐energy gamma photon imaging using list‐mode data acquisition system for high‐dose‐rate brachytherapy

Jura Nagata, Seiichi Yamamoto, Takuya Yabe, Katsunori Yogo, Kohei Nakanishi, Yumiko Noguchi, Kuniyasu Okudaira, Kei Kamada, Akira Yoshikawa, Jun Kataoka

Medical Physics 2022年09月

DOI

Scopus

3

被引用数

(Scopus)
A high-resolution X-ray microscope system for performance evaluation of scintillator plates

Seiichi Yamamoto, Masao Yoshino, Kei Kamada, Ryuga Yajima, Akira Yoshikawa, Mayu Sagisaka, Jun Kataoka

JOURNAL OF INSTRUMENTATION 17 ( 9 ) 2022年09月

　概要を見る

In the development of new scintillators for X-ray imaging, a high-resolution and highly efficient system is required to evaluate the performance of the scintillator plates. For this purpose, we developed a high-resolution X-ray microscope system. The developed compact X-ray microscope system is based on a magnifying unit and a cooled charge-coupled device (CCD) camera, combined with a small industrial X-ray irradiation system. Using this system, we carried out imaging of three scintillator plates and evaluated their spatial resolution. Each scintillator plates was set in front of the lens of the objective, X-rays were irradiated to the scintillator plates, and transmission images of masks were acquired. The measured spatial resolution of the scintillator plates varied from 16 mu m to 30 mu m, depending on the type of scintillator plate. The focus size of the X-ray tube had an almost negligible effect on the spatial resolution of the images for the evaluated scintillator plates.

DOI

Scopus

5

被引用数

(Scopus)
Advantages of using larger-diameter pinhole collimator for prompt X-ray imaging during irradiation with carbon ions

Seiichi Yamamoto, Takuya Yabe, Takashi Akagi, Mitsutaka Yamaguchi, Naoki Kawachi, Kei Kamada, Akira Yoshikawa, Jun Kataoka

Journal of Instrumentation 17 ( 9 ) 2022年09月

　概要を見る

Prompt secondary electron bremsstrahlung X-ray (prompt X-ray) imaging using a low-energy X-ray camera is a promising method for observing a beam shape from outside the subject. However, the images measured within short times suffer from statistical noise. Consequently, we performed prompt X-ray imaging with higher sensitivity using a larger-diameter pinhole collimator and compared the results with those of a conventional collimator. Prompt X-ray imaging was conducted during irradiation with pencil beams of 241.5-MeV/n carbon ions to a water phantom. A newly developed X-ray camera with a 4-mm diameter as well as conventional 1.5-mm-diameter pinhole collimators was used for the imaging in list mode, and we compared the prompt X-ray images, energy spectra, and time count rate curves between 1.5-mm-diameter and 4-mm-diameter pinhole collimators. The prompt X-ray images taken with the 4-mm-diameter pinhole collimators had a1/47 times higher sensitivity with 70 % lower offset fractions originating from the prompt gamma photons. Furthermore, the ranges were more precisely estimated with the 4-mm collimator than with the 1.5-mm collimator. The energy spectra showed less contamination by tungsten-characteristic X-rays for the 4-mm pinhole collimator. Even for images measured with 0.1-s intervals, the beam shapes and time count rate curves could be obtained with less statistical noise using the 4-mm-diameter pinhole collimators. The use of the 4-mm-diameter pinhole collimator attached to the X-ray camera had advantages for prompt X-ray imaging with high sensitivity and low background, enabling us to image the beams even with short-Time measurements.

DOI

Scopus

3

被引用数

(Scopus)
Observation of Spectral Structures in the Flux of Cosmic-Ray Protons from 50 GeV to 60 TeV with the Calorimetric Electron Telescope on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, E. Berti, G. Bigongiari, W. R. Binns, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, K. Ebisawa, A. W. Ficklin, H. Fuke, S. Gonzi, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, G. A. de Nolfo, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, F. Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, W. V. Zober

Physical Review Letters 129 ( 10 ) 2022年09月

DOI
Technical note: Correcting angular dependencies using non‐polarized components of Cherenkov light in water during high‐energy X‐ray irradiation

Chihiro Toyonaga, Seiichi Yamamoto, Takuya Yabe, Kuniyasu Okudaira, Katsunori Yogo, Yoshiyuki Hirano, Jun Kataoka

Medical Physics 49 ( 8 ) 5409 - 5416 2022年08月 [査読有り]

DOI

Scopus

1

被引用数

(Scopus)
Development of a capillary plate based fiber-structured ZnS(Ag) scintillator

Seiichi Yamamoto, Kei Kamada, Masao Yoshino, Akira Yoshikawa, Naoki Sunaguchi, Jun Kataoka

JOURNAL OF INSTRUMENTATION 17 ( 8 ) 2022年08月

　概要を見る

Silver-doped zinc sulfide (ZnS(Ag)) is an opaque powder scintillator that is mainly used for detection or imaging of charged particles such as alpha particles. Since ZnS(Ag) is not transparent, the thickness of ZnS(Ag) was limited to -10 mu m. If a thicker ZnS(Ag) scintillator could be developed, it would be useful for studies such as high-energy particle ion detection as well as beta particle or gamma photon detection. We developed a ZnS(Ag) fiber-structured scintillator using a capillary plate in which ZnS(Ag) powder was encapsulated in the capillaries. The thickness of the capillary plate was 400 mu m, and the light produced in ZnS(Ag) escaped from the capillaries, spread through the transparent lead glass area, and reached the opposite side of the plate; consequently, the opaque character and absorption of light could be avoided. The amount of light emitted from the capillary plate based fiber-structured ZnS(Ag) was almost the same as that of a commercially available ZnS (Ag) film, but the detection efficiency was about 1/5 (-20%). The amount of light emitted from beta particles and gamma photons per MeV was less than 1% of that from alpha particles. The spatial resolution of the developed capillary plate based fiber-structured ZnS(Ag) scintillator for 5.5 MeV alpha particles was -200 mu m FWHM. Imaging of the slits and light spots from alpha particles could be achieved with the developed scintillator combined with an electron-multiplied charge-coupled device (EM-CCD) camera. The developed capillary plate based fiber-structured ZnS(Ag) will be useful for detecting high-energy particle ions.

DOI

Scopus
CALET Search for Electromagnetic Counterparts of Gravitational Waves during the LIGO/Virgo O3 Run

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, E. Berti, G. Bigongiari, W. R. Binns, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, K. Ebisawa, A. W. Ficklin, H. Fuke, S. Gonzi, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, G. A. de Nolfo, S. Okuno, J. F. Ormes, N. Ospina, S. Ozawa, L. Pacini, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, F. Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, W. V. Zober

The Astrophysical Journal 933 ( 1 ) 85 - 85 2022年07月

　概要を見る

Abstract

The CALorimetric Electron Telescope (CALET) on the International Space Station consists of a high-energy cosmic-ray CALorimeter (CAL) and a lower-energy CALET Gamma-ray Burst Monitor (CGBM). CAL is sensitive to electrons up to 20 TeV, cosmic-ray nuclei from Z = 1 through Z ∼ 40, and gamma rays over the range 1 GeV–10 TeV. CGBM observes gamma rays from 7 keV to 20 MeV. The combined CAL-CGBM instrument has conducted a search for gamma-ray bursts (GRBs) since 2015 October. We report here on the results of a search for X-ray/gamma-ray counterparts to gravitational-wave events reported during the LIGO/Virgo observing run O3. No events have been detected that pass all acceptance criteria. We describe the components, performance, and triggering algorithms of the CGBM—the two Hard X-ray Monitors consisting of LaBr₃(Ce) scintillators sensitive to 7 keV–1 MeV gamma rays and a Soft Gamma-ray Monitor BGO scintillator sensitive to 40 keV–20 MeV—and the high-energy CAL consisting of a charge detection module, imaging calorimeter, and the fully active total absorption calorimeter. The analysis procedure is described and upper limits to the time-averaged fluxes are presented.

DOI

Scopus

5

被引用数

(Scopus)
Trials of transmission imaging using clinically used Ir-192 source for high-dose-rate brachytherapy

J. Nagata, S. Yamamoto, K. Nakanishi, Y. Noguchi, K. Okudaira, J. Kataoka

Journal of Instrumentation 17 ( 06 ) T06009 - T06009 2022年06月 [査読有り]

　概要を見る

Abstract

In high-dose-rate (HDR) brachytherapy, verification of an Ir-192 source's position during treatment is required. One of the methods for this used a high-energy pinhole gamma camera to image the position of the source, but the absolute position of the source cannot be measured. To confirm the absolute position, it will be useful to acquire the transmission image of a subject in addition to the gamma photon image at the same time without using an additional X-ray system. To measure the transmission images, we tried to use the high-energy gamma photons emitted from the Ir-192 source used for the therapy. We developed a high-energy gamma photon imaging system composed of 1-mm-thick Pr doped Gd₂O₂S (GOS), a surface mirror, and a cooled charge-coupled device (CCD) camera. The developed imaging system achieved transmission imaging of high-energy gamma photons by transporting the Ir-192 source in front of the imaging system. The spatial resolution of the imaging system was better than 2.4 mm FWHM with and without a 10-cm-thick acrylic block set between the imaging system and the source. Moderate spatial resolution and contrast images of phantoms were obtained with the system. For the dynamic imaging mode, continuous images of the phantoms were measured with 1-sec intervals. There was no observable difference in the transmission images by the movement of the Ir-192 source. Transmission imaging of subjects using an Ir-192 source for HDR brachytherapy could be achieved using our developed imaging system. The system offers a new method to measure the real-time transmission images of the subject during HDR brachytherapy.

DOI
CALET on the International Space Station: a precise measurement of the iron spectrum

O. Adriani, Yosui Akaike, K. Asano, Y. Asaoka, E. Berti, G. Bigongiari, W. R. Binns, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, Caterina Checchia, M. L. Cherry, G. Collazuol, K. Ebisawa, A. W. Ficklin, H. Fuke, S. Gonzi, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, G. A. de Nolfo, S. Okuno, J. F. Ormes, N. Ospina, S. Ozawa, L. Pacini, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, Francesco Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, W. V. Zober

Proceedings of Science 398 2022年05月

　概要を見る

The Calorimetric Electron Telescope (CALET) was launched on the International Space Station in 2015 and since then has collected a large sample of cosmic-ray charged particles over a wide energy. Thanks to a couple of layers of segmented plastic scintillators placed on top of the detector, the instrument is able to identify the charge of individual elements from proton to iron (and above). The imaging tungsten scintillating fiber calorimeter provides accurate particle tracking and the lead tungstate homogeneous calorimeter can measured the energy with a wide dynamic range. One of the CALET scientific objectives is to measure the energy spectra of cosmic rays to shed light on their acceleration and propagation in the Galaxy. By the observation in first five years, a precise measurement of the iron spectrum is now available in the range of kinetic energy per nucleon from 10 GeV/n to 2 TeV/n. The CALET's result with a description of the analysis and details on systematic uncertainties will be illustrated. Also, a comparison with previous experiments' results is given.
Direct Measurement of the Nickel Spectrum in Cosmic Rays in the Energy Range from 8.8 GeV/ n to 240 GeV/ n with CALET on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, E. Berti, G. Bigongiari, W. R. Binns, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, K. Ebisawa, A. W. Ficklin, H. Fuke, S. Gonzi, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, G. A. De Nolfo, S. Okuno, J. F. Ormes, N. Ospina, S. Ozawa, L. Pacini, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, F. Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, W. V. Zober

Physical Review Letters 128 ( 13 ) 2022年04月

　概要を見る

The relative abundance of cosmic ray nickel nuclei with respect to iron is by far larger than for all other transiron elements; therefore it provides a favorable opportunity for a low background measurement of its spectrum. Since nickel, as well as iron, is one of the most stable nuclei, the nickel energy spectrum and its relative abundance with respect to iron provide important information to estimate the abundances at the cosmic ray source and to model the Galactic propagation of heavy nuclei. However, only a few direct measurements of cosmic-ray nickel at energy larger than ∼3 GeV/n are available at present in the literature, and they are affected by strong limitations in both energy reach and statistics. In this Letter, we present a measurement of the differential energy spectrum of nickel in the energy range from 8.8 to 240 GeV/n, carried out with unprecedented precision by the Calorimetric Electron Telescope (CALET) in operation on the International Space Station since 2015. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number Z=40). The particle's energy is measured by a homogeneous calorimeter (1.2 proton interaction lengths, 27 radiation lengths) preceded by a thin imaging section (3 radiation lengths) providing tracking and energy sampling. This Letter follows our previous measurement of the iron spectrum [1O. Adriani (CALET Collaboration), Phys. Rev. Lett. 126, 241101 (2021).PRLTAO0031-900710.1103/PhysRevLett.126.241101], and it extends our investigation on the energy dependence of the spectral index of heavy elements. It reports the analysis of nickel data collected from November 2015 to May 2021 and a detailed assessment of the systematic uncertainties. In the region from 20 to 240 GeV/n our present data are compatible within the errors with a single power law with spectral index -2.51±0.07.

DOI PubMed

Scopus

13

被引用数

(Scopus)
Interaction of the galactic-centre super bubbles with the gaseous disc

Yoshiaki Sofue, Jun Kataoka

Monthly Notices of the Royal Astronomical Society 506 ( 2 ) 2170 - 2180 2021年09月

　概要を見る

The interaction of Galactic centre (GC) super bubbles (GSBs) with the gaseous disc and halo of the Milky Way is investigated using radio continuum, X-ray, H i, and CO line surveys. The radio North Polar Spur (NPS) constitutes the brightest eastern ridge of GSB, brightening towards the galactic plane and reaching l = 22°, b = +2° at the sharpest end, where it intersects the tangential direction of the 3-kpc-expanding ring and crater. Examination of the spur ridges reveals that the entire GSB, including the NPS and its counter spurs, constitutes a GC-symmetrical ω/ω shape. The thickness and gas density of the H i and CO discs are shown to increase sharply from the inside (lower longitude) to the outside the 3-kpc crater. Formation of crater is explained by the sweeping of the upper layer of disc gas by the shock wave from the GC by the explosion ~10 My ago with the emitted energy of several 1055 erg. Based on the discussion, a unified view on the structure and formation mechanism of GSB is presented.

DOI

Scopus

13

被引用数

(Scopus)
Spatial Variations of Magnetic Field along Active Galactic Nuclei Jets on Sub-parsec to Megaparsec Scales

S. Ito, Y. Inoue, J. Kataoka

Astrophysical Journal 916 ( 2 ) 2021年08月

　概要を見る

We report the systematic analysis of knots, hotspots, and lobes in 57 active galactic nuclei (AGNs) to investigate the variation of the magnetic field along the jet from the sub-parsec base to the terminus on kiloparsec-to-megaparsec scales. Expanding the number of radio/X-ray samples in the work of Kataoka & Stawarz, we analyzed the data in 12 FR i and 30 FR ii radio galaxies, 12 quasars, and three BL Lac objects, which contained 76 knots, 42 hotspots, and 29 radio lobes. We first derived the equipartition magnetic fields in the cores and then estimated those in various jet components by assuming B est ∝ d -1, where d is the distance from the jet base. On the other hand, the magnetic field in large-scale jets (knots, hotspots, and lobes), B eq, can be estimated from the observed flux and spatial extent under the equipartition hypothesis. We show that the magnetic field decreases as the distance along the jet increases, but generally in a more gentle way than ∝d -1. The increase in B eq/B est at large d may suggest the deceleration of the jet downstream, but there is no difference between FR i and FR ii jets. Moreover, the magnetic fields in the hotspots are systematically larger than those in knots and lobes. Finally, we applied the same analysis to knots and lobes in Centaurus A to check whether the above discussion will hold even in a single jet source.

DOI

Scopus

3

被引用数

(Scopus)
Measurement of the Iron Spectrum in Cosmic Rays from 10 GeV/n to 2.0 TeV/n with the Calorimetric Electron Telescope on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, E. Berti, G. Bigongiari, W. R. Binns, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, K. Ebisawa, H. Fuke, S. Gonzi, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, J. Link, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, G. A. De Nolfo, S. Okuno, J. F. Ormes, N. Ospina, S. Ozawa, L. Pacini, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, F. Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida

Physical Review Letters 126 ( 24 ) 2021年06月

　概要を見る

The Calorimetric Electron Telescope (CALET), in operation on the International Space Station since 2015, collected a large sample of cosmic-ray iron over a wide energy interval. In this Letter a measurement of the iron spectrum is presented in the range of kinetic energy per nucleon from 10 GeV/n to 2.0 TeV/n allowing the inclusion of iron in the list of elements studied with unprecedented precision by space-borne instruments. The measurement is based on observations carried out from January 2016 to May 2020. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number Z=40). The energy is measured by a homogeneous calorimeter with a total equivalent thickness of 1.2 proton interaction lengths preceded by a thin (3 radiation lengths) imaging section providing tracking and energy sampling. The analysis of the data and the detailed assessment of systematic uncertainties are described and results are compared with the findings of previous experiments. The observed differential spectrum is consistent within the errors with previous experiments. In the region from 50 GeV/n to 2 TeV/n our present data are compatible with a single power law with spectral index -2.60±0.03.

DOI PubMed

Scopus

35

被引用数

(Scopus)
Machine-learning Application to Fermi-LAT Data: Sharpening All-sky Map and Emphasizing Variable Sources

Shogo Sato, Jun Kataoka, Soichiro Ito, Jun'Ichi Kotoku, Masato Taki, Asuka Oyama, Takaya Toyoda, Yuki Nakamura, Marino Yamamoto

Astrophysical Journal 913 ( 2 ) 2021年06月

　概要を見る

A novel application of machine-learning (ML) based image processing algorithms is proposed to analyze an all-sky map (ASM) obtained using the Fermi Gamma-ray Space Telescope. An attempt was made to simulate a 1 yr ASM from a short-exposure ASM generated from 1-week observation by applying three ML-based image processing algorithms: dictionary learning, U-net, and Noise2Noise. Although the inference based on ML is less clear compared to standard likelihood analysis, the quality of the ASM was generally improved. In particular, the complicated diffuse emission associated with the galactic plane was successfully reproduced only from 1-week observation data to mimic a ground truth (GT) generated from a 1 yr observation. Such ML algorithms can be implemented relatively easily to provide sharper images without various assumptions of emission models. In contrast, large deviations between simulated ML maps and the GT map were found, which are attributed to the significant temporal variability of blazar-type active galactic nuclei (AGNs) over a year. Thus, the proposed ML methods are viable not only to improve the image quality of an ASM but also to detect variable sources, such as AGNs, algorithmically, i.e., without human bias. Moreover, we argue that this approach is widely applicable to ASMs obtained by various other missions; thus, it has the potential to examine giant structures and transient events, both of which are rarely found in pointing observations.

DOI

Scopus
Development of a neutron camera system to visualize the dose distribution by secondary neutrons for safer proton therapy

R. Tanaka, J. Kataoka, F. Nishi, H. Yokokawa, T. Inaniwa

Journal of Instrumentation 16 ( 6 ) 2021年06月

　概要を見る

Proton therapy has recently garnered significant attention as an effective treatment for cancer that can effectively damage tumor tissues while reducing doses to healthy tissues and organs. However, secondary neutrons generated by interactions with protons and brass collimators or the patient's body may cause harm to the human body. Nevertheless, the risks are yet to be precisely assessed or reflected in actual treatment plans. In this study, we develop a novel neutron camera that enables the visualization of spatial dose distribution by secondary neutrons. First, a neutron camera comprising two layers of units is constructed; each of the layer is composed of a plastic scintillator coupled with a photomultiplier tube. As a preliminary experiment, it is confirmed that the developed camera can visualize fission neutrons from a 252Cf source. Subsequently, secondary neutrons are observed from a brass (imitating the brass collimator) and water (imitating the patient's body) phantom irradiated with a 70 MeV proton beam, in which the neutron camera is placed at 0°, 15° (only in the case of brass) and 30° from each phantom 30 cm ahead. Following neutron/gamma event selections using two methods, i.e., time of flight and pulse shape discrimination, each of the reconstructed images successfully converged at the correct positions, with average angular resolutions of 21° (brass, full width at half maximum (FWHM)) and 19° (water, FWHM). Furthermore, dosimetry using the G(E) function method is applied to the images, enabling a dose distribution image to be created using secondary neutrons. As a result, the evaluated dose rate is 307 μSv/min for brass and 88.1 μSv/min for water, which are 86 % and 64 % those of the simulated dose rates, respectively. Eventually, future tasks for the utilization of the camera in actual proton therapy are discussed.

DOI

Scopus

2

被引用数

(Scopus)
Application of machine-learning models to improve the image quality of photon-counting CT images

T. Toyoda, S. Sato, H. Kiji, J. Kataoka, J. Kotoku, M. Taki

Journal of Instrumentation 16 ( 5 ) 2021年05月

　概要を見る

X-ray computed tomography (CT) has been widely used in medical diagnostic imaging. However, conventional, energy-integrated CT requires a high radiation dose and can only provide monochromatic images that cannot eliminate various artifacts. In contrast, photon-counting CT (PC-CT) provides low-dose multicolor CT imaging, which enables the identification of multiple contrast agents. However, in the PC-CT system, the lack of photon statistics, which is also caused by image reconstruction in the limited energy band, severely affects the image quality. In this study, we applied three types of machine-learning (ML) techniques to improved the image quality of PC-CT, that is, dictionary learning, U-Net, and Noise2Noise. These ML models were trained using low- and high-dose image pairs created in simple steps. The trained ML models were applied to simulated data, and experimental PC-CT images of contrast agents used in clinical practice. Consequently, in the simulated data, the peak signal-to-noise ratio (PSNR) value improved from 21.3 for the input to 26.6, 33.3, and 30.1 for dictionary learning, U-Net, and Noise2Noise, respectively. Furthermore, in the actual PC-CT images, we successfully reproduced PC-CT images with high PSNR, which enabled simultaneous imaging of multiple contrast agents with improved accuracy of concentration estimation. As a future perspective, we will develop a processing technique that can be applied to in vivo CT images.

DOI

Scopus

2

被引用数

(Scopus)
治療診断統合型スペクトラルCTに向けた低濃度ナノ薬剤イメージングの実証

Dima Djara Sonia, 木地浩章, 豊田貴也, 片岡淳, 有元誠, 佐藤大地, 吉浦宏大龍, 川嶋広貴, 小林聡, 寺澤慎祐, 塩田諭, 池田博一

応用物理学会学術講演会講演予稿集 2021.1 492 - 492 2021年02月

DOI
次世代フォトンカウンティングCTによる多系統イメージングの性能評価

佐藤大地, 有元誠, 吉浦宏大龍, 水野睦也, 川嶋広貴, 小林聡, 片岡淳, 木地浩章, 豊田貴也, Dima Sonia, 池田博一, 寺澤慎祐, 塩田諭

応用物理学会学術講演会講演予稿集 2021.1 491 - 491 2021年02月

DOI
Origin of galactic spurs: New insight from radio/X-ray all-sky maps

Jun Kataoka, Marino Yamamoto, Yuki Nakamura, Soichiro Ito, Yoshiaki Sofue, Yoshiyuki Inoue, Takeshi Nakamori, Tomonori Totani

Astrophysical Journal 908 ( 1 ) 2021年02月

　概要を見る

In this study, we analyze giant Galactic spurs seen in both radio and X-ray all-sky maps to reveal their origins. We discuss two types of giant spurs: one is the brightest diffuse emission near the map's center, which is likely to be related to Fermi bubbles (NPSs/SPSs, north/south polar spurs, respectively), and the other is weaker spurs that coincide positionally with local spiral arms in our Galaxy (LAS, Local Arm spur). Our analysis finds that the X-ray emissions, not only from the NPS but also from the SPS, are closer to the Galactic center by ~5° compared with the corresponding radio emission. Furthermore, larger offsets of 10°-20° are observed in the LASs; however, they are attributed to different physical origins. Moreover, the temperature of the X-ray emission is kT ≃ 0.2 keV for the LAS, which is systematically lower than those of the NPS and SPS (kT ≃ 0.3 keV) but consistent with the typical temperature of Galactic halo gas. We argue that the radio/X-ray offset and the slightly higher temperature of the NPS/SPS X-ray gas are due to the shock compression/heating of halo gas during a significant Galactic explosion in the past, whereas the enhanced X-ray emission from the LAS may be due to the weak condensation of halo gas in the arm potential or star formation activity without shock heating.

DOI

Scopus

3

被引用数

(Scopus)
Performance Estimate of MPPC-based PC-CT System and Initial Results of CT Image Contrast

D. Sato, M. Arimoto, K. Yoshiura, T. Mizuno, K. Aiga, H. Kawashima, S. Kobayashi, J. Kataoka, T. Toyoda, M. Sagisaka, H. Ikeda, S. Terazawa, S. Shiota

2021 IEEE Nuclear Science Symposium and Medical Imaging Conference Record, NSS/MIC 2021 and 28th International Symposium on Room-Temperature Semiconductor Detectors, RTSD 2022 2021年

　概要を見る

X-ray computed tomography (CT) is widely used for three-dimensional nondestructive X-ray imaging of the internal structure of the human body or industrial materials. For modern technology in the medical field, dual-energy CT (DE-CT) with two types of X-ray effective energy has generally been used. However, the X-ray signals of DE-CT are integrated and read out in the form of a current. Thus, contamination with dark noise significantly degrades such imaging qualities as contrast, which causes a large radiation dose to patients. In addition, little energy information on DE-CT results in poor material discrimination of target materials. Recently, the photon-counting CT (PC-CT) system has developed for future CT technology. Because the PC-CT system can detect individual X-ray photons, the dark-noise effect expected to be highly suppressed. The multiple energy data obtained by PC-CT provide fruitful information on the energy dependence of the CT values, leading to high potential for material discrimination. Thus, an MPPC-based PC-CT system combined with high-speed scintillators has been proposed, and a 64-channel CT array system was developed recently. In this study, the details of the performance estimate of the MPPC-based PC-CT system were investigated in terms of energy information and photon-counting capability. The initial results of the CT image contrast compared with the clinical DE-CT system are presented. They show that the proposed PC-CT system achieved a similar contrast-to-noise ratio value to that of the clinical DE-CT.

DOI

Scopus

1

被引用数

(Scopus)
64-channel photon-counting computed tomography using a new MPPC-CT system

H. Kiji, T. Maruhashi, T. Toyoda, J. Kataoka, M. Arimoto, D. Sato, K. Yoshiura, S. Kobayashi, H. Kawashima, S. Terazawa, S. Shiota, H. Ikeda

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 984 2020年12月

　概要を見る

X-ray computed tomography (CT) is a widely used diagnostic tool to visualize the interior of the human body. However, the exposure dose of conventional CT in a single scan is large, typically 10 mSv, and therefore, it is necessary to find ways to reduce the radiation dose. Furthermore, conventional CT does not contain the energy information of individual X-ray photons because the X-ray signals are read out as an integrated form. This causes misidentification of materials. To resolve this issue, we propose a novel photon counting CT (PC-CT) system consisting of multi-pixel photon counters (MPPCs) coupled with high speed scintillators. The system has a 64-channel MPPC array that improves energy information and wide-area imaging. By fine energy adjustment and increasing the number of energy thresholds to six, which were newly implemented in the 64-channel PC-CT system, we succeeded in accurately estimating the concentrations of contrast agents such as iodine and gadolinium. Moreover, for mixed phantoms of iodine and gadolinium, we demonstrate discrimination between them, and estimate the concentrations individually, which cannot be done by conventional CTs. This shows great potential in expanding the applications of X-ray CTs.

DOI

Scopus

15

被引用数

(Scopus)
Direct Measurement of the Cosmic-Ray Carbon and Oxygen Spectra from 10 GeV/ n to 2.2 TeV/ n with the Calorimetric Electron Telescope on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, M. G. Bagliesi, E. Berti, G. Bigongiari, W. R. Binns, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, K. Ebisawa, H. Fuke, S. Gonzi, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, J. Link, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, G. A. De Nolfo, S. Okuno, J. F. Ormes, N. Ospina, S. Ozawa, L. Pacini, F. Palma, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, F. Stolzi, S. Sugita, J. E. Suh, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida

Physical Review Letters 125 ( 25 ) 2020年12月

　概要を見る

In this paper, we present the measurement of the energy spectra of carbon and oxygen in cosmic rays based on observations with the Calorimetric Electron Telescope on the International Space Station from October 2015 to October 2019. Analysis, including the detailed assessment of systematic uncertainties, and results are reported. The energy spectra are measured in kinetic energy per nucleon from 10 GeV/n to 2.2 TeV/n with an all-calorimetric instrument with a total thickness corresponding to 1.3 nuclear interaction length. The observed carbon and oxygen fluxes show a spectral index change of ∼0.15 around 200 GeV/n established with a significance >3σ. They have the same energy dependence with a constant C/O flux ratio 0.911±0.006 above 25 GeV/n. The spectral hardening is consistent with that measured by AMS-02, but the absolute normalization of the flux is about 27% lower, though in agreement with observations from previous experiments including the PAMELA spectrometer and the calorimetric balloon-borne experiment CREAM.

DOI PubMed

Scopus

50

被引用数

(Scopus)
Performance demonstration of a hybrid Compton camera with an active pinhole for wide-band X-ray and gamma-ray imaging

Akihisa Omata, Jun Kataoka, Kazuya Fujieda, Shogo Sato, Eri Kuriyama, Hiroki Kato, Atsushi Toyoshima, Takahiro Teramoto, Kazuhiro Ooe, Yuwei Liu, Keiko Matsunaga, Takashi Kamiya, Tadashi Watabe, Eku Shimosegawa, Jun Hatazawa

Scientific Reports 10 ( 1 ) 2020年12月

　概要を見る

X-ray and gamma-ray imaging are technologies with several applications in nuclear medicine, homeland security, and high-energy astrophysics. However, it is generally difficult to realize simultaneous wide-band imaging ranging from a few tens of keV to MeV because different interactions between photons and the detector material occur, depending on the photon energies. For instance, photoabsorption occurs below 100 keV, whereas Compton scattering dominates above a few hundreds of keV. Moreover, radioactive sources generally emit both X-ray and gamma-ray photons. In this study, we develop a “hybrid” Compton camera that can simultaneously achieve X-ray and gamma-ray imaging by combining features of “Compton” and “pinhole” cameras in a single detector system. Similar to conventional Compton cameras, the detector consists of two layers of scintillator arrays with the forward layer acting as a scatterer for high-energy photons (> 200 keV) and an active pinhole for low-energy photons (< 200 keV). The experimental results on the performance of the hybrid camera were consistent with those from the Geant4 simulation. We simultaneously imaged 241Am (60 keV) and 137Cs (662 keV) in the same field of view, achieving an angular resolution of 10∘ (FWHM) for both sources. In addition, imaging of 211At was conducted for the application in future nuclear medicine, particularly radionuclide therapy. The initial demonstrative images of the 211At phantom were reconstructed using the pinhole mode (using 79 keV) and Compton mode (using 570 keV), exhibiting significant similarities in source-position localization. We also verified that a mouse injected with 1 MBq of 211At can be imaged via pinhole-mode measurement in an hour.

DOI PubMed

Scopus

34

被引用数

(Scopus)
Precision spectroscopy of cesium-137 from the ground to 150 m above in Fukushima

Takuya Kurihara, Kazuhisa Tanada, Jun Kataoka, Hiroki Hosokoshi, Saku Mochizuki, Leo Tagawa, Hiroshi Okochi, Yurie Gotoh

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 978 2020年10月

　概要を見る

After the Fukushima nuclear disaster in 2011, large amounts of radioisotopes (mainly 137Cs and 134Cs) were released into the environment. Various monitoring activities have revealed radiation on the ground both in local and wide areas; however, aerial dose variation in the vertical direction is poorly known. This paper presents the results of airborne gamma-ray spectroscopy of a contamination field in Namie, Fukushima, as measured from 0 m to 150 m above the ground by drone. We found that the gamma-ray dose rate measured at 100 m height is about seven times higher than that expected based on ground measurements, which is caused by two factors: (1) the integrated dose includes contamination of upward scattered 662-keV gamma rays and (2) radiation from 137Cs is vertically collimated because 137Cs is buried in the soil. We also propose a novel method to obtain the distribution of radioactive substances in the soil only through aerial mapping.

DOI

Scopus

2

被引用数

(Scopus)
High-statistics image generation from sparse radiation images by four types of machine-learning models

S. Sato, J. Kataoka, J. Kotoku, M. Taki, A. Oyama, L. Tagawa, K. Fujieda, F. Nishi, T. Toyoda

Journal of Instrumentation 15 ( 10 ) 2020年10月

　概要を見る

With the development of nuclear medicine diagnostics and treatment, the demand for image processing techniques has been increasing. Although single photon emission computed tomography (SPECT) and positron emission tomography (PET) are most common, the energy ranges they permit for imaging are limited to either below 300 keV (SPECT) or to 511 keV gamma rays (PET). Recently, Compton cameras have attracted attention, owing to their wide energy range, which stretches from a few hundred keV to several MeV. In this study, we performed Compton camera image processing using four machine-learning (ML) techniques: dictionary learning, UNet, SRGAN, and AUTOMAP. With these techniques, we tried to reduce the artifacts caused by the sparsity of statistics and improve the signal-to-noise ratio (SNR). Thus, these ML models were trained using image pairs reconstructed from high- and low-statistics images. As a result, we succeeded in generating images similar to the ground truth from low-statistics images. We argue that this technique can be applied not only to Compton camera images but also to other radiation imaging devices. As a future perspective, we mention the possibility of applying our imaging and processing technique to in vivo imaging of alpha-particle internal therapy.

DOI

Scopus

2

被引用数

(Scopus)
Origin of the in-orbit instrumental background of the Hard X-ray Imager onboard Hitomi

Kouichi Hagino, Hirokazu Odaka, Goro Sato, Tamotsu Sato, Hiromasa Suzuki, Tsunefumi Mizuno, Madoka Kawaharada, Masanori Ohno, Kazuhiro Nakazawa, Shogo B. Kobayashi, Hiroaki Murakami, Katsuma Miyake, Makoto Asai, Tatsumi Koi, Greg Madejski, Shinya Saito, Dennis H. Wright, Teruaki Enoto, Yasushi Fukazawa, Katsuhiro Hayashi, Jun Kataoka, Junichiro Katsuta, Motohide Kokubun, Philippe Laurent, François Lebrun, Olivier Limousin, Daniel Maier, Kazuo Makishima, Kunishiro Mori, Takeshi Nakamori, Toshio Nakano, Hirofumi Noda, Masayuki Ohta, Rie Sato, Hiroyasu Tajima, Hiromitsu Takahashi, Tadayuki Takahashi, Shin'Ichiro Takeda, Takaaki Tanaka, Yukikatsu Terada, Hideki Uchiyama, Yasunobu Uchiyama, Shin Watanabe, Kazutaka Yamaoka, Yoichi Yatsu, Takayuki Yuasa

Journal of Astronomical Telescopes, Instruments, and Systems 6 ( 4 ) 2020年10月

　概要を見る

Understanding and reducing in-orbit instrumental backgrounds are essential to achieving high sensitivity in hard x-ray astronomical observations. The observational data of the Hard X-ray Imager (HXI) onboard the Hitomi satellite provide useful information on the background components due to its multilayer configuration with different atomic numbers: The HXI consists of a stack of four layers of Si (Z = 14) detectors and one layer of cadmium telluride (CdTe) (Z = 48, 52) detector surrounded by well-Type Bi4Ge3O12 active shields. Based on the observational data, the backgrounds of the top Si layer, the three underlying Si layers, and the CdTe layer are inferred to be dominated by different components, namely, low-energy electrons, albedo neutrons, and proton-induced radioactivation, respectively. Monte Carlo simulations of the in-orbit background of the HXI reproduce the observed background spectrum of each layer well, thereby quantitatively verifying the above hypothesis. In addition, we suggest the inclusion of an electron shield to reduce the background.

DOI

Scopus

4

被引用数

(Scopus)
First application of the super-resolution imaging technique using a Compton camera

S. Sato, J. Kataoka, J. Kotoku, M. Taki, A. Oyama, L. Tagawa, K. Fujieda, F. Nishi, T. Toyoda

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 969 2020年07月 [査読有り]

　概要を見る

© 2020 Elsevier B.V. In medical imaging, precise and reliable images are very important. However, the quality of medical images is sometimes limited by low-event statistics owing to the low sensitivity of the detectors commonly used in radiology. On the other hand, long exposure to radiation and long inspection duration can become a burden for patients. In this paper, we propose a method for generating high-quality images of gamma ray sources from low statistic data by using machine learning methods based on dictionary learning and sparse coding. As the first application, we generated a high-quality image of 137Cs, which emits 662-keV gamma rays, from low-event statistics measured using a Compton camera. We simulated with Geant4 various geometries of the gamma-ray source (137Cs; 662 keV) as measured with a Compton camera by Geant4. Then, complete sets of low-resolution and high-resolution dictionaries were prepared. We generated super-resolution images from low-resolution test images obtained from actual measurements. The convergence of the gamma-ray images was similar for both the ground truth and predicted images, as supported by the improvements in the structural similarity (SSIM), peak signal-to-noise (PSNR) ratio, and root mean square error (RMSE) in the corresponding images. We also discuss future plans to use the super-resolution technique for visualizing radium chloride (223RaCl2) in the patient's body, which will make it possible to achieve in-vivo imaging of alpha-particle internal therapy for the first time.

DOI

Scopus

8

被引用数

(Scopus)
CALET on the International Space Station: The first three years of observations

P. Brogi, P. Brogi, O. Adriani, O. Adriani, Y. Akaike, Y. Akaike, K. Asano, Y. Asaoka, Y. Asaoka, M. G. Bagliesi, M. G. Bagliesi, E. Berti, E. Berti, G. Bigongiari, G. Bigongiari, W. R. Binns, S. Bonechi, S. Bonechi, M. Bongi, M. Bongi, A. Bruno, J. H. Buckley, N. Cannady, N. Cannady, G. Castellini, C. Checchia, C. Checchia, M. L. Cherry, G. Collazuol, G. Collazuol, V. Di Felice, V. Di Felice, K. Ebisawa, H. Fuke, T. G. Guzik, T. Hams, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, N. Kawanaka, Y. Kawakubo, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, J. F. Krizmanic, J. Link, J. Link, P. Maestro, P. Maestro, P. S. Marrocchesi, P. S. Marrocchesi, A. M. Messineo, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, H. Murakami, S. Nakahira, J. Nishimura, G. A. De Nolfo, S. Okuno, J. F. Ormes, N. Ospina, S. Ozawa, L. Pacini, F. Palma, F. Palma, P. Papini, B. F. Rauch, S. B. Ricciarini, S. B. Ricciarini, K. Sakai, K. Sakai, T. Sakamoto, M. Sasaki, M. Sasaki, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, F. Stolzi, F. Stolzi, S. Sugita, J. E. Suh, J. E. Suh, A. Sulaj

Physica Scripta 95 ( 7 ) 2020年07月

　概要を見る

The CALorimetric Electron Telescope CALET is a space instrument designed to carry out precision measurements of high energy cosmic-rays on the JEM-EF external platform on the International Space Station, where it has been collecting science data continuously since mid October 2015. In addition to its primary goal of identifying nearby sources of high-energy electrons and possible signatures of dark matter in the electron spectrum, CALET is carrying out extensive measurements of the energy spectra, relative abundances and secondary-to-primary ratios of elements from proton to iron, and even above (up to Z = 40), studying the details of galactic particle propagation and acceleration. An overview of CALET based on the data taken during the first three years of observations is presented, including a direct measurement of the electron+positron energy spectrum from 11 GeV to 4.8 TeV. The proton spectrum has been measured from 50 GeV to 10 TeV covering, for the first time with a single space-borne instrument, the whole energy interval previously investigated in separate sub-ranges by magnetic spectrometers and calorimetric instruments. Preliminary spectra of cosmic-ray nuclei are also presented, together with gamma-ray observations and searches for an e.m. counterpart of LIGO/Virgo GW events.

DOI

Scopus

4

被引用数

(Scopus)
Development of Gamma-Ray Detector Arrays Consisting of Diced Eu-Doped SrI<inf>2</inf>Scintillator Arrays and TSV-MPPC Arrays

M. Yoshino, M. Yoshino, K. Kamada, K. Kamada, Y. Shoji, Y. Yokota, S. Kurosawa, A. Yamaji, Y. Ohashi, H. Sato, K. Fujieda, J. Kataoka, A. Yoshikawa, A. Yoshikawa, A. Yoshikawa

IEEE Transactions on Nuclear Science 67 ( 6 ) 999 - 1002 2020年06月 [査読有り]

　概要を見る

© 1963-2012 IEEE. This article presents the development of diced SrI2:Eu arrays and their scintillation properties when coupled with a multipixel photon counter (MPPC) array. Using a dicing technique specific to halide scintillators, a high-energy resolution scintillator array is developed that is cost-effective and widely applicable. The developed SrI2:Eu arrays are of 3 × 3 × 3 mm3/pixel 4 × 4 matrix (TYPE1) and 1 × 1 × 1 mm3/pixel 9 × 9 matrix (TYPE2) structures. We fabricated test gamma-ray detector modules consisting of the TYPE1 and TYPE2 arrays coupled with an MPPC array. The mean peak to valleys ratio is 85.3 ± 14.9 for the TYPE1 array and 38.5 ± 16.6 for the TYPE2 array detector. The average energy resolutions obtained for the TYPE1 and TYPE2 gamma-ray detectors were 5.4 ± 0.4% full-width at half-maximum (FWHM) and 5.2 ± 0.6% FWHM, respectively, for 662-keV gamma-rays. The variation in the signal pulse height of the TYPE1 and TYPE2 detectors was only 10.6% and 10.4% in FWHM, respectively. These results demonstrated that the dicing technique proposed in this article could be applied to hygroscopic halide scintillators.

DOI

Scopus
次世代多色CTに向けた多数造影剤の撮影実証

T.Maruhashi, H.Kiji, T.Toyoda, J.Kataoka, M.Arimoto, S.Kobayashi, H.Kawashima, S.Terazawa, S.Shiota, H.Ikeda

Nuclear Instruments and Methods in Physics Research Section A 958 2020年04月 [査読有り]

DOI

Scopus

9

被引用数

(Scopus)
CALET results after three years on the International Space Station

Y. Asaoka, O. Adriani, Y. Akaike, K. Asano, M. G. Bagliesi, E. Berti, G. Bigongiari, W. R. Binns, S. Bonechi, M. Bongi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, V. Di Felice, K. Ebisawa, H. Fuke, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, J. Link, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, G. A. De Nolfo, S. Okuno, N. Opsina, J. F. Ormes, S. Ozawa, L. Pacini, F. Palma, V. Pal'Shin, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, F. Stolzi, S. Sugita, J. E. Suh, A. Sulaj, I. Takahashi, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida

Journal of Physics: Conference Series 1468 ( 1 ) 2020年03月

　概要を見る

The CALET (CALorimetric Electron Telescope) space experiment, which is currently conducting direct cosmic-ray observations onboard the International Space Station (ISS), is an all-calorimetric instrument optimized for cosmic-ray electron measurements with capability to measure hadrons and gamma-rays. Since the start of observation in October 2015, smooth and continuous operations have taken place. In this paper, we will give a brief summary of the CALET observations ranging from charged cosmic rays, gamma-rays, to space weather, while focusing on the energy spectra of electrons and protons.

DOI

Scopus

2

被引用数

(Scopus)
次世代カラーX線CTに向けたMPPC用64チャンネル高速LSIの開発と性能評価

佐藤大地, 有元誠, 吉浦宏大龍, 川嶋広貴, 小林聡, 片岡淳, 丸橋拓也, 木地浩章, 豊田貴也, 池田博一, 寺澤慎祐, 塩田諭

応用物理学会学術講演会講演予稿集 2020.1 545 - 545 2020年02月

DOI
次世代型カラーX線CTにおける新64チャンネルシステムの性能実証

豊田貴也, 丸橋拓也, 木地浩章, 片岡淳, 有本誠, 佐藤大地, 吉浦宏大龍, 小林聡, 川嶋広貴, 寺澤慎祐, 塩田諭, 池田博一

応用物理学会学術講演会講演予稿集 2020.1 546 - 546 2020年02月

DOI
Beta-ray imaging system with γ-ray coincidence for multiple-tracer imaging

Tomonori Fukuchi, Seiichi Yamamoto, Jun Kataoka, Kei Kamada, Akira Yoshikawa, Yasuyoshi Watanabe, Shuichi Enomoto

Medical Physics 47 ( 2 ) 587 - 596 2020年02月 [査読有り] [国際誌]

　概要を見る

PURPOSE: Beta-ray imaging systems are widely used for various biological objects to obtain a two-dimensional (2D) distribution of β-ray emitting radioisotopes. However, a conventional β-ray imaging system is unsuitable for multiple-tracer imaging, because the continuous energy distribution of β-rays complicates distinguishing among different tracers by energy information. Therefore, we developed a new type of β-ray imaging system, which is useful for multiple tracers by detecting coincidence γ-rays with β-rays, and evaluated its imaging performance. METHODS: Our system is composed of position-sensitive β-ray and γ-ray detectors. The former is a 35 × 35 × 1-mm3 Ce-Doped((La, Gd)2 Si2 O7 ) (La-GPS) scintillation detector, which has a 300-µm pitch of pixels. The latter is a 43 × 43 × 16-mm3 bismuth germanium oxide (BGO) scintillation detector. Both detectors are mounted on a flexible frame and placed in a user-selectable position. We experimentally evaluated the performance of the β-ray detector and the γ-ray efficiencies of the γ-ray detector with different energies, positions, and distances. We also conducted point sources and phantom measurements with dual isotopes to evaluate the system performance of multiple-tracer imaging. RESULTS: For the β-ray detector, the β-ray detection efficiencies for 45 Ca (245-keV maximum energy) and 90 Sr/90 Y (545 and 2280-keV maximum energy) were 14.3% and 21.9%, respectively. The total γ-ray detection efficiency of the γ-ray detector for all γ-rays from 22 Na (511-keV annihilation γ-rays and a 1275-keV γ-ray) in the center position with a detector distance of 20 mm was 17.5%. From a point-source measurement using 22 Na and 90 Sr/90 Y, we successfully extracted the position of a positron-γ emitter 22 Na. Furthermore, for a phantom experiment using 45 Ca and 18 F or 18 F and 22 Na, we successfully extracted the distribution of the second tracer using the annihilation γ-ray or de-excitation γ-ray coincidence. In all the imaging experiments, the event counts of the extracted images were consistent with the counts estimated by the measured γ-ray efficiencies. CONCLUSIONS: We successfully demonstrated the feasibility of our β-ray autoradiography system for imaging multiple isotopes. Since our system can identify not only a β-γ emitter but also a positron emitter using the coincidence detection of annihilation γ-rays, it is useful for PET tracers and various new applications that are otherwise impractical.

DOI PubMed

Scopus

1

被引用数

(Scopus)
RI内用療法におけるコンプトンカメラを用いら223Ra集積の初実証

藤枝和也, 片岡淳, 望月早駆ほか

Nuclear Instruments and Methods in Physics Research Section A in press 2019年12月 [査読有り]

DOI

Scopus

18

被引用数

(Scopus)
MeVガンマ線イメージングのための3次元位置有感型コンプトンカメラの開発と実証

細越裕希, 片岡淳, 望月早駆ほか

Nature Scientific Reports in press ( 1 ) 2019年12月 [査読有り]

DOI PubMed

Scopus

15

被引用数

(Scopus)
ガンマ線イメージングがつなぐ医療と宇宙～超小型コンプトンカメラの挑戦～

片岡淳

応用物理 88 ( 11 ) 730 - 734 2019年11月 [査読有り] [招待有り]

DOI
Stable Radio Core of the Blazar Mrk 501 during High-energy Active State in 2012

Shoko Koyama, Motoki Kino, Akihiro Doi, Kotaro Niinuma, Marcello Giroletti, David Paneque, Kazunori Akiyama, Gabriele Giovannini, Guang-Yao Zhao, Eduardo Ros, Jun Kataoka, Monica Orienti, Kazuhiro Hada, Hiroshi Nagai, Naoki Isobe, Hideyuki Kobayashi, Mareki Honma, Rocco Lico

The Astrophysical Journal 884 ( 2 ) 132 2019年10月 [査読有り]

DOI

Scopus

2

被引用数

(Scopus)
PETを用いた陽子線治療における線量評価ためのML-EMアルゴリスム

T.Masuda, T.Nishio, J.Kataoka, M.Arimoto, K.Karasawa

Physics in Medicine & Biology 64 ( 17 ) 175011 2019年09月 [査読有り]

DOI PubMed

Scopus

14

被引用数

(Scopus)
陽子線治療中の2次被ばく評価のための革新的中性子カメラの開発

田川怜央, 片岡淳, 末岡晃紀ほか

Nuclear Instruments and Methods in Physics Research Section A 936 31 - 33 2019年08月 [査読有り]

DOI

Scopus

5

被引用数

(Scopus)
多色3次元イメージングのための16chMPPCアレイを用いた革新的Photon counting CT システムの評価

丸橋拓也, 森田隼人, 片岡淳ほか

Nuclear Instruments and Methods in Physics Research Section A 936 5 - 9 2019年08月 [査読有り]

DOI

Scopus

16

被引用数

(Scopus)
陽子線治療オンラインモニタに向けた4.4MeV即発ガンマ線の高精度イメージング

望月早駆, 片岡淳, 小出絢子ほか

Nuclear Instruments and Methods in Physics Research Section A 936 43 - 45 2019年08月 [査読有り]

DOI

Scopus

21

被引用数

(Scopus)
Centaurus A kpcジェットにおける星光の逆コンプトン散乱：TeVガンマ線超過成分の起源

棚田和玖, 片岡淳, 井上芳幸

The Astrophysical Journal 878 ( 2 ) 139 - 147 2019年06月 [査読有り]

DOI

Scopus

15

被引用数

(Scopus)
Direct Measurement of the Cosmic-Ray Proton Spectrum from 50 GeV to 10 TeV with the Calorimetric Electron Telescope on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, M. G. Bagliesi, E. Berti, G. Bigongiari, W. R. Binns, S. Bonechi, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, V. Di Felice, K. Ebisawa, H. Fuke, T. G. Guzik, T. Hams, N. Hasebe, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, T. Lomtadze, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, K. Mori, M. Mori, N. Mori, H. M. Motz, K. Munakata, H. Murakami, S. Nakahira, J. Nishimura, G. A. De Nolfo, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, F. Palma, P. Papini, A. V. Penacchioni, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, F. Stolzi, J. E. Suh, A. Sulaj, I. Takahashi, M. Takayanagi, M. Takita, T. Tamura, T. Terasawa, H. Tomida, S. Torii, Y. Tsunesada, Y. Uchihori, S. Ueno, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida

Physical Review Letters 122 ( 18 ) 2019年05月 [査読有り]

　概要を見る

© 2019 authors. In this paper, we present the analysis and results of a direct measurement of the cosmic-ray proton spectrum with the CALET instrument onboard the International Space Station, including the detailed assessment of systematic uncertainties. The observation period used in this analysis is from October 13, 2015 to August 31, 2018 (1054 days). We have achieved the very wide energy range necessary to carry out measurements of the spectrum from 50 GeV to 10 TeV covering, for the first time in space, with a single instrument the whole energy interval previously investigated in most cases in separate subranges by magnetic spectrometers (BESS-TeV, PAMELA, and AMS-02) and calorimetric instruments (ATIC, CREAM, and NUCLEON). The observed spectrum is consistent with AMS-02 but extends to nearly an order of magnitude higher energy, showing a very smooth transition of the power-law spectral index from-2.81±0.03 (50-500 GeV) neglecting solar modulation effects (or-2.87±0.06 including solar modulation effects in the lower energy region) to-2.56±0.04 (1-10 TeV), thereby confirming the existence of spectral hardening and providing evidence of a deviation from a single power law by more than 3σ.

DOI PubMed

Scopus

156

被引用数

(Scopus)
散乱陽子線の革新的補正方法を適用した簡単かつ革新的陽子線CTシステムの開発

高部美帆, 増田孝充, 有元誠, 片岡淳, 末岡晃紀, 丸橋拓也, 田中創大, 西尾禎治, 歳藤利行, 木村充宏, 稲庭拓

Nuclear Instruments and Methods in Physics Research A 924 332 - 338 2019年04月 [査読有り]

DOI

Scopus

2

被引用数

(Scopus)
0.1x0.1mmGAGGプレートシンチレータアレイと1mm角Si-PMを用いた超解像度放射線イメージング検出器

山本誠一, 片岡淳, 鎌田圭, 吉川彰

Nuclear Instruments and Methods in Physics Research, Section A 919 125 - 133 2019年03月 [査読有り]

DOI

Scopus

12

被引用数

(Scopus)
PoGO+を用いた白鳥座X-1 シンクロトロンジェット放射への偏光による制限

Chauvin,M, Florén, Hans-Gustav, Jackson, M

Monthly Notices of the Royal Astronomical Society: Letters, 483 ( 1 ) 138 - 143 2019年02月 [査読有り]

DOI

Scopus

10

被引用数

(Scopus)
革新的ガンマ線イメージングに向けた超小型コンプトンカメラ

片岡淳, 岸本彩, 多屋隆紀ほか

Nuclear Instruments and Methods in Physics Research Section A 912 1 - 5 2018年12月 [査読有り]

DOI

Scopus

15

被引用数

(Scopus)
Correction: Shedding new light on the crab with polarized X-rays (Scientific Reports DOI: 10.1038/s41598-017-07390-7)

M. Chauvin, H. G. Florén, M. Friis, M. Jackson, T. Kamae, J. Kataoka, T. Kawano, M. Kiss, V. Mikhalev, T. Mizuno, N. Ohashi, T. Stana, H. Tajima, H. Takahashi, N. Uchida, M. Pearce

Scientific Reports 8 ( 1 ) 2018年12月

　概要を見る

This Article contains a typographical error in the legend of Figure 2. "Gaussian 1, 2 and 3& #x1D70E;" should read: "Gaussian 1, 2 and 3σ".

DOI PubMed

Scopus

1

被引用数

(Scopus)
Detection of polarized gamma-ray emission from the Crab nebula with the Hitomi Soft Gamma-ray Detector

Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W. Bautz, Roger Blandford, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Jelle De Plaa, Cor P. De Vries, Jan Willem Den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Junko S. Hiraga, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masachika Iwai, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Nobuyuki Kawai, Richard L. Kelley, Caroline A. Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A. Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, Shiu Hang Lee, Maurice A. Leutenegger, Olivier Limousin, Michael Loewenstein, Knox S. Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian R. McNamara, Missagh Mehdipour, Eric D. Miller, Jon M. Miller, Shin Mineshige

Publications of the Astronomical Society of Japan 70 ( 6 ) 2018年12月

　概要を見る

We present the results from the Hitomi Soft Gamma-ray Detector (SGD) observation of the Crab nebula. The main part of SGD is a Compton camera, which in addition to being a spectrometer, is capable of measuring polarization of gamma-ray photons. The Crab nebula is one of the brightest X-ray/gamma-ray sources on the sky, and the only source from which polarized X-ray photons have been detected. SGD observed the Crab nebula during the initial test observation phase of Hitomi. We performed data analysis of the SGD observation, SGD background estimation, and SGD Monte Carlo simulations and successfully detected polarized gamma-ray emission from the Crab nebula with only about 5 ks exposure time. The obtained polarization fraction of the phase-integrated Crab emission (sum of pulsar and nebula emissions) is (22.1%±10.6%), and the polarization angle is 110°.7 + 13°.2/-13°.0 in the energy range of 60.160 keV (the errors correspond to the 1 σ deviation). The confidence level of the polarization detection was 99.3%. The polarization angle measured by SGD is about one sigma deviation with the projected spin axis of the pulsar, 124°.0 ± 0°.0.1.

DOI

Scopus

24

被引用数

(Scopus)
高精度陽子線治療に向けた、チェレンコフ光を用いた核反応断面積の精密測定

増田孝充, 片岡淳, 有元誠ほか

Nature Scientific Reports 8 ( 1 ) 2570 2018年12月 [査読有り]

DOI PubMed

Scopus

27

被引用数

(Scopus)
3次元位置有感型コンプトンカメラを用いた4.4MeVガンマ線の高精度測定

小出絢子, 片岡淳, 増田孝充ほか

Nature Scientific Reports 8 ( 1 ) 8116 2018年12月 [査読有り]

DOI PubMed

Scopus

43

被引用数

(Scopus)
Characteristics and Performance of the CALorimetric Electron Telescope (CALET) Calorimeter for Gamma-Ray Observations

N. Cannady, Y. Asaoka, F. Satoh, M. Tanaka, S. Torii, M. L. Cherry, M. Mori, O. Adriani, Y. Akaike, K. Asano, M. G. Bagliesi, E. Berti, G. Bigongiari, W. R. Binns, S. Bonechi, M. Bongi, P. Brogi, J. H. Buckley, G. Castellini, C. Checchia, G. Collazuol, V. Di Felice, K. Ebisawa, H. Fuke, T. G. Guzik, T. Hams, M. Hareyama, N. Hasebe, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, T. Lomtadze, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, K. Mori, N. Mori, H. M. Motz, K. Munakata, H. Murakami, S. Nakahira, J. Nishimura, G. A.De Nolfo, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, F. Palma, P. Papini, A. V. Penacchioni, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, F. Stolzi, J. E. Suh, A. Sulaj, I. Takahashi, M. Takayanagi, M. Takita, T. Tamura, N. Tateyama, T. Terasawa, H. Tomida, Y. Tsunesada, Y. Uchihori, S. Ueno, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida

Astrophysical Journal, Supplement Series 238 ( 1 ) 2018年09月

　概要を見る

The CALorimetric Electron Telescope primary detector (CALET-CAL) is a 30 radiation-length-deep hybrid calorimeter designed for the accurate measurement of high-energy cosmic rays. It is capable of triggering on and giving near complete containment of electromagnetic showers from primary electrons and gamma rays from 1 GeV to over 10 TeV. The first 24 months of on-orbit scientific data (2015 November 01-2017 October 31) provide valuable characterization of the performance of the calorimeter based on analyses of the gamma-ray data set in general and bright point sources in particular. We describe the gamma-ray analysis, the expected performance of the calorimeter based on Monte Carlo simulations, the agreement of the flight data with the simulated results, and the outlook for long-term gamma-ray observations with the CAL.

DOI

Scopus

19

被引用数

(Scopus)
Search for GeV Gamma-Ray Counterparts of Gravitational Wave Events by CALET

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, M. G. Bagliesi, E. Berti, G. Bigongiari, W. R. Binns, S. Bonechi, M. Bongi, P. Brogi, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, V. Di Felice, K. Ebisawa, H. Fuke, T. G. Guzik, T. Hams, M. Hareyama, N. Hasebe, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, H. S. Krawczynski, J. F. Krizmanic, K. Kohri, T. Lomtadze, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, K. Mori, M. Mori, N. Mori, H. M. Motz, K. Munakata, H. Murakami, S. Nakahira, J. Nishimura, G. A. De Nolfo, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, F. Palma, P. Papini, A. V. Penacchioni, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, F. Stolzi, J. E. Suh, A. Sulaj, I. Takahashi, M. Takayanagi, M. Takita, T. Tamura, N. Tateyama, T. Terasawa, H. Tomida, S. Torii, Y. Tsunesada, Y. Uchihori, S. Ueno, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida

Astrophysical Journal 863 ( 2 ) 2018年08月 [査読有り]

　概要を見る

© 2018. The American Astronomical Society. All rights reserved. We present the results of searches for gamma-ray counterparts of the LIGO/Virgo gravitational wave events using CALorimetric Electron Telescope (CALET) observations. The main instrument of CALET, CALorimeter (CAL), observes gamma-rays from ∼1 GeV up to 10 TeV with a field of view (FOV) of nearly 2 sr. In addition, the CALET gamma-ray burst monitor views ∼3 sr and ∼2π sr of the sky in the 7 keV-1 MeV and the 40 keV-20 MeV bands, respectively, by using two different crystal scintillators. The CALET observations on the International Space Station started in 2015 October, and here we report analyses of events associated with the following gravitational wave events: GW151226, GW170104, GW170608, GW170814, and GW170817. Although only upper limits on gamma-ray emission are obtained, they correspond to a luminosity of 1049 ∼ 1053 erg s-1 in the GeV energy band depending on the distance and the assumed time duration of each event, which is approximately on the order of luminosity of typical short gamma-ray bursts. This implies that there will be a favorable opportunity to detect high-energy gamma-ray emission in further observations if additional gravitational wave events with favorable geometry will occur within our FOV. We also show the sensitivity of CALET for gamma-ray transient events, which is on the order of 10-7 erg cm-2 s-1 for an observation of 100 s in duration.

DOI

Scopus

20

被引用数

(Scopus)
硬X線偏光をもちいたブラックホール連星Cyg X-1 の降着構造の観測

M.Chauvin, G.Floren, M.Jackson

Nature Astronomy 2 ( 8 ) 652 - 655 2018年08月 [査読有り]

DOI

Scopus

36

被引用数

(Scopus)
Spatial Distribution of the Milky Way Hot Gaseous Halo Constrained by Suzaku X-Ray Observations

Shinya Nakashima, Yoshiyuki Inoue, Noriko Yamasaki, Yoshiaki Sofue, Jun Kataoka, Kazuhiro Sakai

Astrophysical Journal 862 ( 1 ) 2018年07月

　概要を見る

The formation mechanism of the hot gaseous halo associated with the Milky Way is still under debate. We report new observational constraints on the gaseous halo using 107 lines of sight of the Suzaku X-ray observations at 75°< l < 285° and with a total exposure of 6.4 Ms. The gaseous halo spectra are represented by a singleerature plasma model in collisional ionization equilibrium. The median temperature of the observed fields is 0.26 keV (3.0 × 106 K) with a typical fluctuation of ∼30%. The emission measure varies by an order of magnitude and marginally correlates with the Galactic latitude. Despite the large scatter of the data, the emission measure distribution is roughly reproduced by a disk-like density distribution with a scale length of ∼7 kpc, a scale height of ∼2 kpc, and a total mass of ∼5 × 107 M. In addition, we found that a spherical hot gas with the β-model profile hardly contributes to the observed X-rays but that its total mass might reach 109 M. Combined with indirect evidence of an extended gaseous halo from other observations, the hot gaseous halo likely consists of a dense disk-like component and a rarefied spherical component; the X-ray emissions primarily come from the former, but the mass is dominated by the latter. The disk-like component likely originates from stellar feedback in the Galactic disk due to the low scale height and the large scatter of the emission measures. The median [O/Fe] of ∼0.25 shows the contribution of the core-collapse supernovae and supports the stellar feedback origin.

DOI

Scopus

64

被引用数

(Scopus)
すざく衛星を用いた、ループI構造北部からの拡散X線観測

秋田誠博, 片岡淳, 有元誠ほか

Astrophysical Journal 862 ( 1 ) 88 2018年07月 [査読有り]

DOI

Scopus

12

被引用数

(Scopus)
On-orbit operations and offline data processing of CALET onboard the ISS

Y. Asaoka, S. Ozawa, S. Torii, O. Adriani, Y. Akaike, K. Asano, M. G. Bagliesi, G. Bigongiari, W. R. Binns, S. Bonechi, M. Bongi, P. Brogi, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, V. Di Felice, K. Ebisawa, H. Fuke, T. G. Guzik, T. Hams, M. Hareyama, N. Hasebe, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, A. Javaid, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, H. S. Krawczynski, J. F. Krizmanic, S. Kuramata, T. Lomtadze, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, K. Mizutani, A. A. Moiseev, K. Mori, M. Mori, N. Mori, H. M. Motz, K. Munakata, H. Murakami, S. Nakahira, J. Nishimura, G. A. de Nolfo, S. Okuno, J. F. Ormes, L. Pacini, F. Palma, P. Papini, A. V. Penacchioni, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, F. Stolzi, I. Takahashi, M. Takayanagi, M. Takita, T. Tamura, N. Tateyama, T. Terasawa, H. Tomida, Y. Tsunesada, Y. Uchihori, S. Ueno, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, T. Yuda

Astroparticle Physics 100 29 - 37 2018年07月

　概要を見る

The CALorimetric Electron Telescope (CALET), launched for installation on the International Space Station (ISS) in August, 2015, has been accumulating scientific data since October, 2015. CALET is intended to perform long-duration observations of high-energy cosmic rays onboard the ISS. CALET directly measures the cosmic-ray electron spectrum in the energy range of 1 GeV to 20 TeV with a 2% energy resolution above 30 GeV. In addition, the instrument can measure the spectrum of gamma rays well into the TeV range, and the spectra of protons and nuclei up to a PeV. In order to operate the CALET onboard ISS, JAXA Ground Support Equipment (JAXA-GSE) and the Waseda CALET Operations Center (WCOC) have been established at JAXA and Waseda University, respectively. Scientific operations using CALET are planned at WCOC, taking into account orbital variations of geomagnetic rigidity cutoff. Scheduled command sequences are used to control the CALET observation modes on orbit. Calibration data acquisition by, for example, recording pedestal and penetrating particle events, a low-energy electron trigger mode operating at high geomagnetic latitude, a low-energy gamma-ray trigger mode operating at low geomagnetic latitude, and an ultra heavy trigger mode, are scheduled around the ISS orbit while maintaining maximum exposure to high-energy electrons and other high-energy shower events by always having the high-energy trigger mode active. The WCOC also prepares and distributes CALET flight data to collaborators in Italy and the United States. As of August 31, 2017, the total observation time is 689 days with a live time fraction of the total time of ∼ 84%. Nearly 450 million events are collected with a high-energy (E > 10 GeV) trigger. In addition, calibration data acquisition and low-energy trigger modes, as well as an ultra-heavy trigger mode, are consistently scheduled around the ISS orbit. By combining all operation modes with the excellent-quality on-orbit data collected thus far, it is expected that a five-year observation period will provide a wealth of new and interesting results.

DOI

Scopus

47

被引用数

(Scopus)
Extended Measurement of the Cosmic-Ray Electron and Positron Spectrum from 11 GeV to 4.8 TeV with the Calorimetric Electron Telescope on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, M. G. Bagliesi, E. Berti, G. Bigongiari, W. R. Binns, S. Bonechi, M. Bongi, P. Brogi, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, V. Di Felice, K. Ebisawa, H. Fuke, T. G. Guzik, T. Hams, M. Hareyama, N. Hasebe, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, T. Lomtadze, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, K. Mori, M. Mori, N. Mori, H. M. Motz, K. Munakata, H. Murakami, S. Nakahira, J. Nishimura, G. A. De Nolfo, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, F. Palma, P. Papini, A. V. Penacchioni, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, F. Stolzi, J. E. Suh, A. Sulaj, I. Takahashi, M. Takayanagi, M. Takita, T. Tamura, N. Tateyama, T. Terasawa, H. Tomida, S. Torii, Y. Tsunesada, Y. Uchihori, S. Ueno, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida

Physical Review Letters 120 ( 26 ) 2018年06月 [査読有り]

　概要を見る

© 2018 American Physical Society. Extended results on the cosmic-ray electron + positron spectrum from 11 GeV to 4.8 TeV are presented based on observations with the Calorimetric Electron Telescope (CALET) on the International Space Station utilizing the data up to November 2017. The analysis uses the full detector acceptance at high energies, approximately doubling the statistics compared to the previous result. CALET is an all-calorimetric instrument with a total thickness of 30 X0 at normal incidence and fine imaging capability, designed to achieve large proton rejection and excellent energy resolution well into the TeV energy region. The observed energy spectrum in the region below 1 TeV shows good agreement with Alpha Magnetic Spectrometer (AMS-02) data. In the energy region below ∼300 GeV, CALET's spectral index is found to be consistent with the AMS-02, Fermi Large Area Telescope (Fermi-LAT), and Dark Matter Particle Explorer (DAMPE), while from 300 to 600 GeV the spectrum is significantly softer than the spectra from the latter two experiments. The absolute flux of CALET is consistent with other experiments at around a few tens of GeV. However, it is lower than those of DAMPE and Fermi-LAT with the difference increasing up to several hundred GeV. The observed energy spectrum above ∼1 TeV suggests a flux suppression consistent within the errors with the results of DAMPE, while CALET does not observe any significant evidence for a narrow spectral feature in the energy region around 1.4 TeV. Our measured all-electron flux, including statistical errors and a detailed breakdown of the systematic errors, is tabulated in the Supplemental Material in order to allow more refined spectral analyses based on our data.

DOI PubMed

Scopus

179

被引用数

(Scopus)
フェルミ衛星の8年データを用いたNGC1275からのガンマ線フラックス変動の起源

棚田和玖, 片岡淳, 有元誠ほか

The Astrophysical Journal 860 ( 1 ) 74 2018年06月 [査読有り]

DOI

Scopus

23

被引用数

(Scopus)
Hitomi X-ray observation of the pulsar wind nebula G21.5-0.9

Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W. Bautz, Roger Blandford, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Jelle De Plaa, Cor P. De Vries, Jan Willem Den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Junko S. Hiraga, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masachika Iwai, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Nobuyuki Kawai, Richard L. Kelley, Caroline A. Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A. Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, Shiu Hang Lee, Maurice A. Leutenegger, Olivier Limousin, Michael Loewenstein, Knox S. Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian R. McNamara, Missagh Mehdipour, Eric D. Miller, Jon M. Miller, Shin Mineshige

Publications of the Astronomical Society of Japan 70 ( 3 ) 2018年06月

　概要を見る

We present results from the Hitomi X-ray observation of a young composite-type supernova remnant (SNR) G21.5-0.9, whose emission is dominated by the pulsar wind nebula (PWN) contribution. The X-ray spectra in the 0.8-80 keV range obtained with the Soft X-ray Spectrometer (SXS), Soft X-ray Imager, and Hard X-ray Imager (HXI) show a significant break in the continuum as previously found with the NuSTAR observation. After taking into account all known emissions from the SNR other than the PWN itself, we find that the Hitomi spectra can be fitted with a broken power law with photon indices of 1 = 1.74 ± 0.02 and 2 = 2.14 ± 0.01 below and above the break at 7.1 ± 0.3 keV, which is significantly lower than the NuSTAR result (∼9.0 keV). The spectral break cannot be reproduced by time-dependent particle injection one-zone spectral energy distribution models, which strongly indicates that a more complex emission model is needed, as suggested by recent theoretical models. We also search for narrow emission or absorption lines with the SXS, and perform a timing analysis of PSR J1833-1034 with the HXI and the Soft Gamma-ray Detector. No significant pulsation is found from the pulsar. However, unexpectedly, narrow absorption line features are detected in the SXS data at 4.2345 keV and 9.296 keV with a significance of 3.65 s. While the origin of these features is not understood, their mere detection opens up a new field of research and was only possible with the high resolution, sensitivity, and ability to measure extended sources provided by an X-ray microcalorimeter.

DOI

Scopus

11

被引用数

(Scopus)
1mm角MPPCアレイと0.2mmピッチGAGGプレートを用いた超解像度放射線イメージャの開発

山本誠一, 片岡淳, 福地知則ほか

Journal of Instrumentation 13 ( 5 ) P05028 2018年05月

DOI

Scopus

4

被引用数

(Scopus)
Modeling of proton-induced radioactivation background in hard X-ray telescopes: Geant4-based simulation and its demonstration by Hitomi's measurement in a low Earth orbit

Odaka Hirokazu, Asai Makoto, Hagino Kouichi, Koi Tatsumi, Madejski Greg, Mizuno Tsunefumi, Ohno Masanori, Saito Shinya, Sato Tamotsu, Wright Dennis H, Enoto Teruaki, Fukazawa Yasushi, Hayashi Katsuhiro, Kataoka Jun, Katsuta Junichiro, Kawaharada Madoka, Kobayashi Shogo B, Kokubun Motohide, Laurent Philippe, Lebrun Francois, Limousin Olivier, Maier Daniel, Makishima Kazuo, Mimura Taketo, Miyake Katsuma, Mori Kunishiro, Murakami Hiroaki, Nakamori Takeshi, Nakano Toshio, Nakazawa Kazuhiro, Noda Hirofumi, Ohta Masayuki, Ozaki Masanobu, Sato Goro, Sato Rie, Tajima Hiroyasu, Takahashi Hiromitsu, Takahashi Tadayuki, Takeda Shin'ichiro, Tanaka Takaaki, Tanaka Yasuyuki, Terada Yukikatsu, Uchiyama Hideki, Uchiyama Yasunobu, Watanabe Shin, Yamaoka Kazutaka, Yasuda Tetsuya, Yatsu Yoichi, Yuasa Takayuki, Zoglauer Andreas

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 891 92 - 105 2018年05月 [査読有り]

DOI

Scopus

15

被引用数

(Scopus)
In-orbit performance and calibration of the Hard X-ray Imager onboard Hitomi (ASTRO-H)

Kouichi Hagino, Kazuhiro Nakazawa, Goro Sato, Motohide Kokubun, Teruaki Enoto, Yasushi Fukazawa, Katsuhiro Hayashi, Jun Kataoka, Junichiro Katsuta, Shogo B. Kobayashi, Philippe Laurent, Francois Lebrun, Olivier Limousin, Daniel Maier, Kazuo Makishima, Taketo Mimura, Katsuma Miyake, Tsunefumi Mizuno, Kunishiro Mori, Hiroaki Murakami, Takeshi Nakamori, Toshio Nakano, Hirofumi Noda, Hirokazu Odaka, Masanori Ohno, Masayuki Ohta, Shinya Saito, Rie Sato, Hiroyasu Tajima, Hiromitsu Takahashi, Tadayuki Takahashi, Shin'ichiro Takeda, Takaaki Tanaka, Yukikatsu Terada, Hideki Uchiyama, Yasunobu Uchiyama, Shin Watanabe, Kazutaka Yamaoka, Yoichi Yatsu, Takayuki Yuasa

Journal of Astronomical Telescopes, Instruments, and Systems 4 ( 2 ) 2018年04月

　概要を見る

The Hard X-ray Imager (HXI) onboard Hitomi (ASTRO-H) is an imaging spectrometer covering hard x-ray energies of 5 to 80 keV. Combined with the Hard X-ray Telescope, it enables imaging spectroscopy with an angular resolution of 10.7 half-power diameter, in a field of view of 9' × 9'. The main imager is composed of four layers of Si detectors and one layer of CdTe detector, stacked to cover a wide energy band up to 80 keV, surrounded by an active shield made of Bi4Ge3O12 scintillator to reduce the background. The HXI started observations 12 days before the Hitomi loss and successfully obtained data from G21.5-0.9, Crab, and blank sky. Utilizing these data, we calibrate the detector response and study properties of in-orbit background. The observed Crab spectra agree well with a powerlaw model convolved with the detector response, within 5% accuracy. We find that albedo electrons in specified orbit strongly affect the background of the Si top layer and establish a screening method to reduce it. The background level over the full field of view after all the processing and screening is as low as the preflight requirement of 1 - 3 × 10-4 counts s-1 cm-2 keV-1.

DOI

Scopus

14

被引用数

(Scopus)
Design and performance of Soft Gamma-ray Detector onboard the Hitomi (ASTRO-H) satellite

Tajima Hiroyasu, Watanabe Shin, Fukazawa Yasushi, Blandford Roger, Enoto Teruaki, Goldwurm Andrea, Hagino Kouichi, Hayashi Katsuhiro, Ichinohe Yuto, Kataoka Jun, Katsuta Jun'ichiro, Kitaguchi Takao, Kokubun Motohide, Laurent Philippe, Lebrun Francois, Limousin Olivier, Madejski Grzegorz M, Makishima Kazuo, Mizuno Tsunefumi, Mori Kunishiro, Nakamori Takeshi, Nakano Toshio, Nakazawa Kazuhiro, Noda Hirofumi, Odaka Hirokazu, Ohno Masanori, Ohta Masayuki, Saito Shinya, Sato Goro, Sato Rie, Takeda Shin'ichiro, Takahashi Hiromitsu, Takahashi Tadayuki, Tanaka Takaaki, Tanaka Yasuyuki, Terada Yukikatsu, Uchiyama Hideki, Uchiyama Yasunobu, Yamaoka Kazutaka, Yatsu Yoichi, Yonetoku Daisuke, Yuasao Takayuki

JOURNAL OF ASTRONOMICAL TELESCOPES INSTRUMENTS AND SYSTEMS 4 ( 2 ) 2018年04月 [査読有り]

DOI

Scopus

22

被引用数

(Scopus)
Hard x-ray imager onboard Hitomi (ASTRO-H)

Nakazawa Kazuhiro, Sato Goro, Kokubun Motohide, Enoto Teruaki, Fukazawa Yasushi, Hagino Kouichi, Hayashi Katsuhiro, Kataoka Jun, Katsuta Junichiro, Kobayashi Shogo B, Laurent Philippe, Lebrun Francois, Limousin Olivier, Maier Daniel, Makishima Kazuo, Mizuno Tsunefumi, Mori Kunishiro, Nakamori Takeshi, Nakano Toshio, Noda Hirofumi, Odaka Hirokazu, Ohno Masanori, Ohta Masayuki, Saito Shinya, Sato Rie, Tajima Hiroyasu, Takahashi Hiromitsu, Takahashi Tadayuki, Takeda Shin'ichiro, Tanaka Takaaki, Terada Yukikatsu, Uchiyama Hideki, Uchiyama Yasunobu, Watanabe Shin, Yamaoka Kazutaka, Yatsu Yoichi, Yuasa Takayuki

JOURNAL OF ASTRONOMICAL TELESCOPES INSTRUMENTS AND SYSTEMS 4 ( 2 ) 2018年04月 [査読有り]

DOI

Scopus

40

被引用数

(Scopus)
Hitomi observation of radio galaxy NGC 1275: The first X-ray microcalorimeter spectroscopy of Fe-Kα line emission from an active galactic nucleus

Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W. Bautz, Roger Blandford, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Jelle De Plaa, Cor P. De Vries, Jan Willem Den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Junko S. Hiraga, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masachika Iwai, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Nobuyuki Kawai, Richard L. Kelley, Caroline A. Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A. Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, Shiu Hang Lee, Maurice A. Leutenegger, Olivier O. Limousin, Michael Loewenstein, Knox S. Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian R. McNamara, Missagh Mehdipour, Eric D. Miller, Jon M. Miller, Shin Mineshige

Publications of the Astronomical Society of Japan 70 ( 2 ) 2018年03月

　概要を見る

The origin of the narrow Fe-Kα fluorescence line at 6.4 keV from active galactic nuclei has long been under debate; some of the possible sites are the outer accretion disk, the broad line region, a molecular torus, or interstellar/intracluster media. In 2016 February-March, we performed the first X-ray microcalorimeter spectroscopy with the Soft X-ray Spectrometer (SXS) on board the Hitomi satellite of the Fanaroff-Riley type I radio galaxy NGC 1275 at the center of the Perseus cluster of galaxies. With the high-energy resolution of ∼5 eV at 6 keV achieved by Hitomi/SXS, we detected the Fe-Kα line with ∼5.4 σ significance. The velocity width is constrained to be 500-1600 km s−1 (FWHM for Gaussian models) at 90% confidence. The SXS also constrains the continuum level from the NGC 1275 nucleus up to ∼20 keV, giving an equivalent width of ∼20 eV for the 6.4 keV line. Because the velocity width is narrower than that of the broad Hα line of ∼2750 km s−1, we can exclude a large contribution to the line flux from the accretion disk and the broad line region. Furthermore, we performed pixel map analyses on the Hitomi/SXS data and image analyses on the Chandra archival data, and revealed that the Fe-Kα line comes from a region within ∼1.6 kpc of the NGC 1275 core, where an active galactic nucleus emission dominates, rather than that from intracluster media. Therefore, we suggest that the source of the Fe-Kα line from NGC 1275 is likely a low-covering-fraction molecular torus or a rotating molecular disk which probably extends from a parsec to hundreds of parsecs scale in the active galactic nucleus system.

DOI

Scopus

16

被引用数

(Scopus)
Search for thermal X-ray features from the Crab nebula with the Hitomi soft X-ray spectrometer

Takashi J. Moriya, Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W. Bautz, Roger Blandford, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Jelle De Plaa, Cor P. De Vries, Jan Willem Den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Junko S. Hiraga, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Nobuyuki Kawai, Richard L. Kelley, Caroline A. Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A. Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, Shiu Hang Lee, Maurice A. Leutenegger, Olivier Limousin, Michael Loewenstein, Knox S. Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan Mccammon, Brian R. Mcnamara, Missagh Mehdipour, Eric D. Miller, Jon M. Miller, Shin Mineshige

Publications of the Astronomical Society of Japan 70 ( 2 ) 2018年03月

　概要を見る

The Crab nebula originated from a core-collapse supernova (SN) explosion observed in 1054AD. When viewed as a supernova remnant (SNR), it has an anomalously low observed ejecta mass and kinetic energy for an Fe-core-collapse SN. Intensive searches have been made for a massive shell that solves this discrepancy, but none has been detected. An alternative idea is that SN 1054 is an electron-capture (EC) explosion with a lower explosion energy by an order of magnitude than Fe-core-collapse SNe. X-ray imaging searches were performed for the plasma emission from the shell in the Crab outskirts to set a stringent upper limit on the X-ray emitting mass. However, the extreme brightness of the source hampers access to its vicinity. We thus employed spectroscopic technique using the X-ray micro-calorimeter on board the Hitomi satellite. By exploiting its superb energy resolution, we set an upper limit for emission or absorption features from as yet undetected thermal plasma in the 2-12keV range. We also re-evaluated the existing Chandra and XMM-Newton data. By assembling these results, a new upper limit was obtained for the X-ray plasma mass of < 1 M⊙ for a wide range of assumed shell radius, size, and plasma temperature values both in and out of collisional equilibrium. To compare with the observation, we further performed hydrodynamic simulations of the Crab SNR for two SN models (Fe-core versus EC) under two SN environments (uniform interstellar medium versus progenitor wind). We found that the observed mass limit can be compatible with both SN models if the SN environment has a low density of < 0.03 cm-3 (Fe core) or < 0.1 cm-3 (EC) for the uniform density, or a progenitor wind density somewhat less than that provided by a mass loss rate of 10-5M⊙ yr-1 at 20 km s-1for the wind environment.

DOI

Scopus

5

被引用数

(Scopus)
Glimpse of the highly obscured HMXB IGR J16318-4848 with Hitomi

Steven W. Alle, Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W. Bautz, Roger Blandford, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Jelle De Plaa, Cor P. De Vries, Jan Willem Den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Junko S. Hiraga, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masachika Iwai, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Nobuyuki Kawai, Richard L. Kelley, Caroline A. Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A. Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, Shiu Hang Lee, Maurice A. Leutenegger, Olivier O. Limousin, Michael Loewenstein, Knox S. Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan Mccammon, Brian R. Mcnamara, Missagh Mehdipour, Eric D. Miller, Jon M. Miller

Publications of the Astronomical Society of Japan 70 ( 2 ) 2018年03月

　概要を見る

We report on a Hitomi observation of IGRJ16318-4848, a high-mass X-ray binary system with an extremely strong absorption of NH ∼ 1024cm 2. Previous X-ray studies revealed that its spectrum is dominated by strong fluorescence lines of Fe as well as continuum emission lines. For physical and geometrical insight into the nature of the reprocessing material, we utilized the high spectroscopic resolving power of the X-ray microcalorimeter (the soft X-ray spectrometer: SXS) and the wide-band sensitivity by the soft and hard X-ray imagers (SXI and HXI) aboard Hitomi. Even though the photon counts are limited due to unintended off-axis pointing, the SXS spectrum resolves Fe Kα1 and Kα2 lines and puts strong constraints on the line centroid and line width. The line width corresponds to a velocity of 160+-37000 km s-1. This represents the most accurate, and smallest, width measurement of this line made so far from the any X-ray binary, much less than the Doppler broadening and Doppler shift expected from speeds that are characteristic of similar systems. Combined with the K-shell edge energy measured by the SXI and HXI spectra, the ionization state of Fe is estimated to be in the range of Fe I-IV. Considering the estimated ionization parameter and the distance between the X-ray source and the absorber, the density and thickness of the materials are estimated. The extraordinarily strong absorption and the absence of a Compton shoulder component have been confirmed. These characteristics suggest reprocessing materials that are distributed in a narrow solid angle or scattering, primarily by warm free electrons or neutral hydrogen. This measurement was achieved using the SXS detection of 19 photons. It provides strong motivation for follow-up observations of this and other X-ray binaries using the X-ray Astrophysics Recovery Mission and other comparable future instruments.

DOI

Scopus

6

被引用数

(Scopus)
Hitomi X-ray studies of giant radio pulses from the Crab pulsar

Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W. Bautz, Roger Blandford, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Jelle De Plaa, Cor P. De Vries, Jan Willem Den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Junko S. Hiraga, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masachika Iwai, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Nobuyuki Kawai, Richard L. Kelley, Caroline A. Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A. Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, L. E.E. Shiu-Hang, Maurice A. Leutenegger, Olivier O. Limousin, Michael Loewenstein, Knox S. Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian R. McNamara, Missagh Mehdipour, Eric D. Miller, Jon M. Miller, Shin Mineshige

Publications of the Astronomical Society of Japan 70 ( 2 ) 2018年03月

　概要を見る

To search for giant X-ray pulses correlated with the giant radio pulses (GRPs) from the Crab pulsar, we performed a simultaneous observation of the Crab pulsar with the X-ray satellite Hitomi in the 2-300 keV band and the Kashima NICT radio telescope in the 1.4-1.7 GHz band with a net exposure of about 2 ks on 2016 March 25, just before the loss of the Hitomi mission. The timing performance of the Hitomi instruments was confirmed to meet the timing requirement and about 1000 and 100 GRPs were simultaneously observed at the main pulse and inter-pulse phases, respectively, and we found no apparent correlation between the giant radio pulses and the X-ray emission in either the main pulse or inter-pulse phase. All variations are within the 2 σ fluctuations of the X-ray fluxes at the pulse peaks, and the 3 σ upper limits of variations of main pulse or inter-pulse GRPs are 22% or 80% of the peak flux in a 0.20 phase width, respectively, in the 2-300 keV band. The values for main pulse or inter-pulse GRPs become 25% or 110%, respectively, when the phase width is restricted to the 0.03 phase. Among the upper limits from the Hitomi satellite, those in the 4.5-10 keV and 70-300 keV bands are obtained for the first time, and those in other bands are consistent with previous reports. Numerically, the upper limits of the main pulse and inter-pulse GRPs in the 0.20 phase width are about (2.4 and 9.3) × 10−11 erg cm−2, respectively. No significant variability in pulse profiles implies that the GRPs originated from a local place within the magnetosphere. Although the number of photon-emitting particles should temporarily increase to account for the brightening of the radio emission, the results do not statistically rule out variations correlated with the GRPs, because the possible X-ray enhancement may appear due to a >0.02% brightening of the pulse-peak flux under such conditions.
Measurements of resonant scattering in the Perseus Cluster core with Hitomi SXS

Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W. Bautz, Roger Blandford, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Jelle De Plaa, Cor P. De Vries, Jan Willem Den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Maki Furukawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Junko S. Hiraga, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masachika Iwai, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Nobuyuki Kawai, Richard L. Kelley, Caroline A. Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A. Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, Shiu Hang Lee, Maurice A. Leutenegger, Olivier O. Limousin, Michael Loewenstein, Knox S. Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian R. McNamara, Missagh Mehdipour, Eric D. Miller, Jon M. Miller

Publications of the Astronomical Society of Japan 70 ( 2 ) 2018年03月

　概要を見る

Thanks to its high spectral resolution (∼5 eV at 6 keV), the Soft X-ray Spectrometer (SXS) on board Hitomi enables us to measure the detailed structure of spatially resolved emission lines from highly ionized ions in galaxy clusters for the first time. In this series of papers, using the SXS we have measured the velocities of gas motions, metallicities and the multi-temperature structure of the gas in the core of the Perseus Cluster. Here, we show that when inferring physical properties from line emissivities in systems like Perseus, the resonant scattering effect should be taken into account. In the Hitomi waveband, resonant scattering mostly affects the Fe XXV Heα line (w)-the strongest line in the spectrum. The flux measured by Hitomi in this line is suppressed by a factor of ∼1.3 in the inner ∼30 kpc, compared to predictions for an optically thin plasma; the suppression decreases with the distance from the center. The w line also appears slightly broader than other lines from the same ion. The observed distortions of the w line flux, shape, and distance dependence are all consistent with the expected effect of the resonant scattering in the Perseus core. By measuring the ratio of fluxes in optically thick (w) and thin (Fe XXV forbidden, Heβ, Lyα) lines, and comparing these ratios with predictions from Monte Carlo radiative transfer simulations, the velocities of gas motions have been obtained. The results are consistent with the direct measurements of gas velocities from line broadening described elsewhere in this series, although the systematic and statistical uncertainties remain significant. Further improvements in the predictions of line emissivities in plasma models, and deeper observations with future X-ray missions offering similar or better capabilities to the Hitomi SXS, will enable resonant scattering measurements to provide powerful constraints on the amplitude and anisotropy of cluster gas motions.

DOI

Scopus

20

被引用数

(Scopus)
Hitomi observations of the LMC SNR N 132 D: Highly redshifted X-ray emission from iron ejecta

Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W. Bautz, Roger Blandford, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Jelle De Plaa, Cor P. De Vries, Jan Willem Den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Junko S. Hiraga, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masachika Iwai, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Nobuyuki Kawai, Richard L. Kelley, Caroline A. Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A. Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, Shiu Hang Lee, Maurice A. Leutenegger, Olivier Limousin, Michael Loewenstein, Knox S. Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian R. McNamara, Missagh Mehdipour, Eric D. Miller, Jon M. Miller, Shin Mineshige

Publications of the Astronomical Society of Japan 70 ( 2 ) 2018年03月

　概要を見る

We present Hitomi observations of N 132 D, a young, X-ray bright, O-rich core-collapse supernova remnant in the Large Magellanic Cloud (LMC). Despite a very short observation of only 3.7 ks, the Soft X-ray Spectrometer (SXS) easily detects the line complexes of highly ionized S K and Fe K with 16-17 counts in each. The Fe feature is measured for the first time at high spectral resolution. Based on the plausible assumption that the Fe K emission is dominated by He-like ions, we find that the material responsible for this Fe emission is highly redshifted at ∼ 800 km s−1 compared to the local LMC interstellar medium (ISM), with a 90% credible interval of 50-1500 km s−1 if a weakly informative prior is placed on possible line broadening. This indicates (1) that the Fe emission arises from the supernova ejecta, and (2) that these ejecta are highly asymmetric, since no blueshifted component is found. The S K velocity is consistent with the local LMC ISM, and is likely from swept-up ISM material. These results are consistent with spatial mapping that shows the He-like Fe concentrated in the interior of the remnant and the S tracing the outer shell. The results also show that even with a very small number of counts, direct velocity measurements from Doppler-shifted lines detected in extended objects like supernova remnants are now possible. Thanks to the very low SXS background of ∼ 1 event per spectral resolution element per 100 ks, such results are obtainable during short pointed or slew observations with similar instruments. This highlights the power of high-spectral-resolution imaging observations, and demonstrates the new window that has been opened with Hitomi and will be greatly widened with future missions such as the X-ray Astronomy Recovery Mission (XARM) and Athena.

DOI

Scopus

6

被引用数

(Scopus)
Temperature structure in the Perseus cluster core observed with Hitomi

Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W. Bautz, Roger Blandford, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Jelle De Plaa, Cor P. De Vries, Jan Willem Den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Maki Furukawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Junko S. Hiraga, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masachika Iwai, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Yuichi Kato, Satoru Katsuda, Nobuyuki Kawai, Richard L. Kelley, Caroline A. Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A. Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, Shiu Hang Lee, Maurice A. Leutenegger, Olivier Limousin, Michael Loewenstein, Knox S. Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian R. McNamara, Missagh Mehdipour, Eric D. Miller

Publications of the Astronomical Society of Japan 70 ( 2 ) 2018年03月

　概要を見る

The present paper explains the temperature structure of X-ray emitting plasma in the core of the Perseus cluster based on 1.8-20.0 keV data obtained with the Soft X-ray Spectrometer (SXS) on board the Hitomi Observatory. A series of four observations was carried out, with a total effective exposure time of 338 ks that covered a central region of ∼7 in diameter. SXS was operated with an energy resolution of ∼5 eV (full width at half maximum) at 5.9 keV. Not only fine structures of K-shell lines in He-like ions, but also transitions from higher principal quantum numbers were clearly resolved from Si through Fe. That enabled us to perform temperature diagnostics using the line ratios of Si, S, Ar, Ca, and Fe, and to provide the first direct measurement of the excitation temperature and ionization temperature in the Perseus cluster. The observed spectrum is roughly reproduced by a single-temperature thermal plasma model in collisional ionization equilibrium, but detailed line-ratio diagnostics reveal slight deviations from this approximation. In particular, the data exhibit an apparent trend of increasing ionization temperature with the atomic mass, as well as small differences between the ionization and excitation temperatures for Fe, the only element for which both temperatures could be measured. The best-fit two-temperature models suggest a combination of 3 and 5 keV gas, which is consistent with the idea that the observed small deviations from a single-temperature approximation are due to the effects of projecting the known radial temperature gradient in the cluster core along the line of sight. A comparison with the Chandra/ACIS and the XMM-Newton/RGS results, on the other hand, suggests that additional lower-temperature components are present in the intracluster medium (ICM), but not detectable with Hitomi/SXS giving its 1.8-20 keV energy band.

DOI

Scopus

15

被引用数

(Scopus)
Atmospheric gas dynamics in the Perseus cluster observed with Hitomi

Felix Aharonia, Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W. Bautz, Roger Blandford, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Rebecca E.A. Canning, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Jelle De Plaa, Cor P. De Vries, Jan Willem Den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Tasuku Hayashi, Kiyoshi Hayashida, Junko S. Hiraga, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Shota Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masachika Iwai, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Nobuyuki Kawai, Richard L. Kelley, Caroline A. Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A. Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, Shiu Hang Lee, Maurice A. Leutenegger, Olivier Limousin, Michael Loewenstein, Knox S. Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan Mccammon, Brian R. Mcnamara

Publications of the Astronomical Society of Japan 70 ( 2 ) 2018年03月

　概要を見る

Extending the earlier measurements reported in Hitomi collaboration (2016, Nature, 535, 117), we examine the atmospheric gas motions within the central 100kpc of the Perseus cluster using observations obtained with the Hitomi satellite. After correcting for the point spread function of the telescope and using optically thin emission lines, we find that the line-of-sight velocity dispersion of the hot gas is remarkably low and mostly uniform. The velocity dispersion reaches a maxima of approximately 200 km s-1 toward the central active galactic nucleus (AGN) and toward the AGN inflated northwestern "ghost" bubble. Elsewhere within the observed region, the velocity dispersion appears constant around 100 km s-1. We also detect a velocity gradient with a 100 km s-1 amplitude across the cluster core, consistent with large-scale sloshing of the core gas. If the observed gas motions are isotropic, the kinetic pressure support is less than 10% of the thermal pressure support in the cluster core. The well-resolved, optically thin emission lines have Gaussian shapes, indicating that the turbulent driving scale is likely below 100 kpc, which is consistent with the size of the AGN jet inflated bubbles. We also report the first measurement of the ion temperature in the intracluster medium, which we find to be consistent with the electron temperature. In addition, we present a new measurement of the redshift of the brightest cluster galaxy NGC 1275.
Atomic data and spectral modeling constraints from high-resolution X-ray observations of the Perseus cluster with Hitomi

Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W. Bautz, Roger Blandford, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Jelle De Plaa, Cor P. De Vries, Jan Willem Den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Natalie Hell, Junko S. Hiraga, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masachika Iwai, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Nobuyuki Kawai, Richard L. Kelley, Caroline A. Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A. Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, Shiu Hang Lee, Maurice A. Leutenegger, Olivier Limousin, Michael Loewenstein, Knox S. Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian R. McNamara, Missagh Mehdipour, Eric D. Miller, Jon M. Miller

Publications of the Astronomical Society of Japan 70 ( 2 ) 2018年03月

　概要を見る

The Hitomi Soft X-ray Spectrometer spectrum of the Perseus cluster, with ∼5 eV resolution in the 2-9 keV band, offers an unprecedented benchmark of the atomic modeling and database for hot collisional plasmas. It reveals both successes and challenges of the current atomic data and models. The latest versions of AtomDB/APEC (3.0.8), SPEX (3.03.00), and CHIANTI (8.0) all provide reasonable fits to the broad-band spectrum, and are in close agreement on best-fit temperature, emission measure, and abundances of a few elements such as Ni. For the Fe abundance, the APEC and SPEX measurements differ by 16%, which is 17 times higher than the statistical uncertainty. This is mostly attributed to the differences in adopted collisional excitation and dielectronic recombination rates of the strongest emission lines. We further investigate and compare the sensitivity of the derived physical parameters to the astrophysical source modeling and instrumental effects. The Hitomi results show that accurate atomic data and models are as important as the astrophysical modeling and instrumental calibration aspects. Substantial updates of atomic databases and targeted laboratory measurements are needed to get the current data and models ready for the data from the next Hitomi-level mission.

DOI

Scopus

30

被引用数

(Scopus)
Ｘ線およびがガンマ線を用いたフェルミ・バブルとNPS/Loop 構造の観測

片岡淳, 祖父江義明, 井上芳幸ほか

Galaxies 6 ( 1 ) 27 - 46 2018年02月 [査読有り] [招待有り]

DOI

Scopus

46

被引用数

(Scopus)
将来の宇宙科学ミッションに向けたCe:GAGGシンチレータの性能評価

米山昌樹, 片岡淳, 有元誠ほか

Journal of Instrumentation 13 ( 2 ) P020203 2018年02月 [査読有り]

DOI

Scopus

54

被引用数

(Scopus)
PoGO+ によるカニ星雲のオフパルス硬X線放射の観測

M.Chauvin, G.Floren, M.Jackson

Monthly Notices of the Royal Astronomical Society: Letters, 477 ( 1 ) 45 - 49 2018年02月 [査読有り]

DOI

Scopus

16

被引用数

(Scopus)
X線衛星「ひとみ」搭載軟ガンマ線検出器(SGD)によるかに星雲のガンマ線偏光観測

渡辺伸, 大野雅功, 小高裕和, 片岡淳, 勝田隼一郎, 北口貴雄, 国分紀秀, Goldwurm Andrea, 斉藤新也, 佐藤悟朗, 佐藤理江, 内田悠介, 高橋忠幸, 高橋弘充, 武田伸一郎, 田中孝明, 田中康之, 寺田幸功, 中澤知洋, 中野俊男, 中森健之, 野田博文, 田島宏康, 萩野浩一, 林克洋, Blandford Roger, 牧島一夫, Madejski Grzegorz, 水野恒史, 森國城, 谷津陽一, 山岡和貴, 湯浅孝行, 深沢泰司, 米徳大輔, Laurent Philippe, Limousin Olivier, Lebrun François, ほかSGDチーム, 一戸悠人, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之

日本物理学会講演概要集 73 492 - 492 2018年

DOI CiNii
CTA報告134：CTA大口径望遠鏡搭載光電子増倍管の経年変化の研究

櫻井駿介, 片岡淳, 片桐秀明, 木村颯一朗, 櫛田淳子, 窪秀利, 郡司修一, 小山志勇, 今野裕介, 齋藤隆之, 澤田真理, 永吉勤, 砂田裕志, 高橋光成, 辻本晋平, 手嶋政廣, 寺田幸功, 門叶冬樹, 中嶋大輔, 中森健之, 西嶋恭司, 西山楽, 稲田知大, 野崎誠也, 林田将明, 馬場彩, 平子丈, 深見哲志, 増田周, 山本常夏, 吉田龍生, Hadasch D., Mazin D., 猪目祐介, 他 CTA-Japan consortium, 岩村由樹, 大岡秀行, 奥村曉, 岡崎奈緒, 折戸玲子

日本物理学会講演概要集 73 ( 0 ) 417 - 417 2018年

DOI CiNii
CTA報告133：CTA大口径望遠鏡初号機の焦点面カメラ統合試験

野崎誠也, 片桐秀明, 加藤翔, 木村颯一朗, 櫛田淳子, 窪秀利, 郡司修一, 小山志勇, 今野裕介, 齋藤隆之, 櫻井駿介, 稲田知大, 澤田真理, 砂田裕志, 高橋光成, 高原大, 田中真伸, 辻本晋平, 手嶋政廣, 寺田幸功, 門叶冬樹, 中嶋大輔, 猪目祐介, 中森健之, 永吉勤, 西嶋恭司, 西山楽, 林田将明, 馬場彩, 平子丈, 深見哲志, 増田周, 山本常夏, 岩村由樹, 吉田龍生, Hadasch D., Mazin D., 他CTA-Japan consortium, 池野正弘, 内田智久, 大岡秀行, 奥村曉, 岡崎奈緒, 折戸玲子, 片岡淳

日本物理学会講演概要集 73 ( 0 ) 416 - 416 2018年

DOI CiNii
CTA報告142：CTA大口径望遠鏡初号機の焦点面カメラ統合試験(II)

砂田裕志, 片桐秀明, 櫛田淳子, 木村颯一朗, 窪秀利, 郡司修一, 小山志勇, 齋藤隆之, 櫻井駿介, 澤田真理, 鈴木萌, 稲田知大, 高橋光成, 高原大, 田中真伸, 辻本晋平, 手嶋政廣, 寺田幸功, 門叶冬樹, 中嶋大輔, 中森健之, 永吉勤, 猪目祐介, 西嶋恭司, 西山楽, 野崎誠也, 林田将明, 馬場彩, 平子丈, 深見哲志, 増田周, 山本常夏, 吉田龍生, 岩村由樹, Hadasch Daniela, Mazin Daniel, 他CTA-Japan consortium, 大岡秀行, 岡崎奈緒, 奥村曉, 折戸玲子, 片岡淳

日本物理学会講演概要集 73 ( 0 ) 191 - 191 2018年

DOI CiNii
Energy Spectrum of Cosmic-Ray Electron and Positron from 10 GeV to 3 TeV Observed with the Calorimetric Electron Telescope on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, M. G. Bagliesi, G. Bigongiari, W. R. Binns, S. Bonechi, M. Bongi, P. Brogi, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, V. Di Felice, K. Ebisawa, H. Fuke, T. G. Guzik, T. Hams, M. Hareyama, N. Hasebe, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, A. Javaid, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, H. S. Krawczynski, J. F. Krizmanic, S. Kuramata, T. Lomtadze, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, K. Mizutani, A. A. Moiseev, K. Mori, M. Mori, N. Mori, H. M. Motz, K. Munakata, H. Murakami, S. Nakahira, J. Nishimura, G. A. De Nolfo, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, F. Palma, P. Papini, A. V. Penacchioni, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, F. Stolzi, I. Takahashi, M. Takayanagi, M. Takita, T. Tamura, N. Tateyama, T. Terasawa, H. Tomida, S. Torii, Y. Tsunesada, Y. Uchihori, S. Ueno, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, T. Yuda

Physical Review Letters 119 ( 18 ) 2017年11月

　概要を見る

First results of a cosmic-ray electron and positron spectrum from 10 GeV to 3 TeV is presented based upon observations with the CALET instrument on the International Space Station starting in October, 2015. Nearly a half million electron and positron events are included in the analysis. CALET is an all-calorimetric instrument with total vertical thickness of 30 X0 and a fine imaging capability designed to achieve a large proton rejection and excellent energy resolution well into the TeV energy region. The observed energy spectrum over 30 GeV can be fit with a single power law with a spectral index of -3.152±0.016 (stat+syst). Possible structure observed above 100 GeV requires further investigation with increased statistics and refined data analysis.

DOI PubMed

Scopus

150

被引用数

(Scopus)
Solar abundance ratios of the iron-peak elements in the Perseus cluster

Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W. Bautz, Roger Blandford, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Jelle De Plaa, Jan-Willem den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Junko S. Hiraga, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masachika Iwai, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Nobuyuki Kawai, Richard L. Kelley, Caroline A. Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A. Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, Shiu-Hang Lee, Maurice A. Leutenegger, Olivier Limousine, Michael Loewenstein, Knox S. Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian R. McNamara, Missagh Mehdipour, Eric D. Miller, Jon M. Miller, Shin Mineshige, Kazuhisa Mitsuda, Ikuyuki Mitsuishi, Takuya Miyazawa, Tsunefumi Mizuno, Hideyuki Mori, Koji Mori, Koji Mukai, Hiroshi Murakami, Richard F. Mushotzky, Takao Nakagawa, Hiroshi Nakajima, Takeshi Nakamori, Shinya Nakashima, Kazuhiro Nakazawa, Kumiko K. Nobukawa, Masayoshi Nobukawa, Hirofumi Noda, Hirokazu Odaka, Takaya Ohashi, Masanori Ohno, Takashi Okajima, Naomi Ota, Masanobu Ozaki, Frits Paerels, StPhane Paltani, Robert Petre, Ciro Pinto, Frederick S. Porter, Katja Pottschmidt, Christopher S. Reynolds, Samar Safi-Harb, Shinya Saito, Kazuhiro Sakai, Toru Sasaki, Goro Sato, Kosuke Sato, Rie Sato, Makoto Sawada, Norbert Schartel, Peter J. Serlemitsos, Hiromi Seta, Megumi Shidatsu, Aurora Simionescu, Randall K. Smith, Yang Soong, Lukasz Stawarz, Yasuharu Sugawara, Satoshi Sugita, Andrew Szymkowiak, Hiroyasu Tajima, Hiromitsu Takahashi, Tadayuki Takahashi, Shin'ichiro Takeda, Yoh Takei, Toru Tamagawa, Takayuki Tamura, Takaaki Tanaka, Yasuo Tanaka, Yasuyuki T. Tanaka, Makoto S. Tashiro, Yuzuru Tawara, Yukikatsu Terada, Yuichi Terashima, Francesco Tombesi, Hiroshi Tomida, Yohko Tsuboi, Masahiro Tsujimoto, Hiroshi Tsunemi, Takeshi Go Tsuru, Hiroyuki Uchida, Hideki Uchiyama, Yasunobu Uchiyama, Shutaro Ueda, Yoshihiro Ueda, Shin'ichiro Uno, C. Megan Urry, Eugenio Ursino, Cor P. de Vries, Shin Watanabe, Norbert Werner, Daniel R. Wik, Dan R. Wilkins, Brian J. Williams, Shinya Yamada, Hiroya Yamaguchi, Kazutaka Yamaoka, Noriko Y. Yamasaki, Makoto Yamauchi, Shigeo Yamauchi, Tahir Yaqoob, Yoichi Yatsu, Daisuke Yonetoku, Irina Zhuravleva, Abderahmen Zoghbi

NATURE 551 ( 7681 ) 478 - + 2017年11月 [査読有り]

　概要を見る

The metal abundance of the hot plasma that permeates galaxy clusters represents the accumulation of heavy elements produced by billions of supernovae(1). Therefore, X-ray spectroscopy of the intracluster medium provides an opportunity to investigate the nature of supernova explosions integrated over cosmic time. In particular, the abundance of the iron-peak elements (chromium, manganese, iron and nickel) is key to understanding how the progenitors of typical type Ia supernovae evolve and explode(2-6). Recent X-ray studies of the intracluster medium found that the abundance ratios of these elements differ substantially from those seen in the Sun(7-11), suggesting differences between the nature of type Ia supernovae in the clusters and in the Milky Way. However, because the K-shell transition lines of chromium and manganese are weak and those of iron and nickel are very close in photon energy, highresolution spectroscopy is required for an accurate determination of the abundances of these elements. Here we report observations of the Perseus cluster, with statistically significant detections of the resonance emission from chromium, manganese and nickel. Our measurements, combined with the latest atomic models, reveal that these elements have near-solar abundance ratios with respect to iron, in contrast to previous claims. Comparison between our results and modern nucleosynthesis calculations(12-14) disfavours the hypothesis that type Ia supernova progenitors are exclusively white dwarfs with masses well below the Chandrasekhar limit (about 1.4 times the mass of the Sun). The observed abundance pattern of the iron-peak elements can be explained by taking into account a combination of near-and sub-Chandrasekhar-mass type Ia supernova systems, adding to the mounting evidence that both progenitor types make a substantial contribution to cosmic chemical enrichment(5,15,16).

DOI PubMed

Scopus

72

被引用数

(Scopus)
超高線量化イメージングに向けた新型ピンホールカメラの開発

末岡晃紀, 片岡淳, 高部美帆ほか

Nuclear Instruments and Methods in Physics Research Section A 912 115 - 118 2017年11月 [査読有り]

DOI

Scopus

10

被引用数

(Scopus)
陽子線治療に向けた広帯域即発ガンマ線の空間分解測定

小出絢子, 片岡淳, 多屋隆紀ほか

Nuclear Instruments and Methods in Physics Research Section A 912 24 - 28 2017年11月 [査読有り]

DOI

Scopus

3

被引用数

(Scopus)
MPPCを用いたフォトンカウンティングCT用LSIの開発

有元誠, 森田隼人, 片岡淳ほか

Nuclear instruments & methods in physics research. Section A 912 186 - 190 2017年11月 [査読有り]

DOI

Scopus

10

被引用数

(Scopus)
高精細LYSO-GAGGシンチレータとSi-PMを用いた高解像度SPECT検出器の性能評価

中西恒平, 山本誠一, 片岡淳

Nuclear Instruments and Methods in Physics Research Section A 872 ( 11 ) 107 - 111 2017年11月 [査読有り]

DOI

Scopus

13

被引用数

(Scopus)
ドローンを用いた福島上空からのガンマ線イメージングの実証

望月早駆, 片岡淳, 田川怜央ほか

Journal of Instrumentation 12 ( 11 ) P11014 2017年11月 [査読有り]

DOI

Scopus

38

被引用数

(Scopus)
Development of gamma-ray detector sensitive to source directions using GAGG(Ce) scintillators and MPPCs

Keiki Kojima, Takeshi Nakamori, Daiki Nemoto, Shuichi Gunji, Hiroki Sato, Shigeki Ito, Sho Kato, Masao Yoshino, Yoshiyuki Usuki, Jun Kataoka

2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop, NSS/MIC/RTSD 2016 2017-January 2017年10月 [査読有り]

　概要を見る

© 2016 IEEE. We have developed a simpler, smaller, and thus less expensive gamma-ray detector that can roughly determine the incident direction of a radiation source with moderate angular resolution, aiming for personal use beyond that afforded by conventional survey meters. The detector consists of six GAGG(Ce) scintillators with dimensions of 20 × 20 × 6 mm3 on each face of a 3-cm cubic lead block. Signals from each scintillator are read by a 3 × 3 mm2 Hamamatsu MPPC. We then applied χ2 fit to the observed count number set in order to determine the incident direction and set our angular accuracy goal of 22.5°. Through simulation, we injected 662 keV gamma rays uniformly from in front of the detector. We found that the R90 is distributed from 6.0° to 18.3° in all 980 directions for one-minute exposure to a 137Cs source that gives 0.15 μSv/h. Furthermore, our detector achieved the targeted value under BG intensity of 0.25 μSv/h in the experiment.

DOI

Scopus

3

被引用数

(Scopus)
大気球を用いたカニ星雲の硬X線偏光観測

M.Chauvin, G.Floren, M.Fris e

Nature Scientific Reports 7 ( 1 ) 7816 2017年08月 [査読有り]

DOI PubMed

Scopus

39

被引用数

(Scopus)
即発ガンマ線イメージングに向けたコンプトンカメラ画像再構成法の最適化

多屋隆紀, 片岡淳, 岸本彩ほか

Journal of Instrumentation 12 ( 7 ) P07015 - P07015 2017年07月 [査読有り]

DOI

Scopus

23

被引用数

(Scopus)
MPPCを用いた革新的低被ばくX線フォトンカウンティングCTシステムの開発

森田隼人, 大島翼, 片岡淳ほか

Nuclear Instruments and Methods in Physics Research Section A 857 ( 11 ) 58 - 65 2017年06月 [査読有り]

DOI

Scopus

19

被引用数

(Scopus)
Energy calibration of CALET onboard the International Space Station

Y. Asaoka, Y. Akaike, Y. Komiya, R. Miyata, S. Torii, O. Adriani, K. Asano, M. G. Bagliesi, G. Bigongiari, W. R. Binns, S. Bonechi, M. Bongi, P. Brogi, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, V. Di Felice, K. Ebisawa, H. Fuke, T. G. Guzik, T. Hams, M. Hareyama, N. Hasebe, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, A. Javaid, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, H. Kitamura, H. S. Krawczynski, J. F. Krizmanic, S. Kuramata, T. Lomtadze, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, K. Mizutani, A. A. Moiseev, K. Mori, M. Mori, N. Mori, H. M. Motz, K. Munakata, H. Murakami, Y. E. Nakagawa, S. Nakahira, J. Nishimura, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, F. Palma, P. Papini, A. V. Penacchioni, B. F. Rauch, S. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, F. Stolzi, I. Takahashi, M. Takayanagi, M. Takita, T. Tamura, N. Tateyama, T. Terasawa, H. Tomida, Y. Tsunesada, Y. Uchihori, S. Ueno, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, T. Yuda

Astroparticle Physics 91 1 - 10 2017年05月 [査読有り]

　概要を見る

© 2017 The Authors In August 2015, the CALorimetric Electron Telescope (CALET), designed for long exposure observations of high energy cosmic rays, docked with the International Space Station (ISS) and shortly thereafter began to collect data. CALET will measure the cosmic ray electron spectrum over the energy range of 1 GeV to 20 TeV with a very high resolution of 2% above 100 GeV, based on a dedicated instrument incorporating an exceptionally thick 30 radiation-length calorimeter with both total absorption and imaging (TASC and IMC) units. Each TASC readout channel must be carefully calibrated over the extremely wide dynamic range of CALET that spans six orders of magnitude in order to obtain a degree of calibration accuracy matching the resolution of energy measurements. These calibrations consist of calculating the conversion factors between ADC units and energy deposits, ensuring linearity over each gain range, and providing a seamless transition between neighboring gain ranges. This paper describes these calibration methods in detail, along with the resulting data and associated accuracies. The results presented in this paper show that a sufficient accuracy was achieved for the calibrations of each channel in order to obtain a suitable resolution over the entire dynamic range of the electron spectrum measurement.

DOI

Scopus

70

被引用数

(Scopus)
「てのひら」サイズ・コンプトンカメラを用いた多色3次元生体イメージングの実証

岸本彩, 片岡淳, 多屋隆紀ほか

Nature Scientific Repprts 7 ( 1 ) 2110 2017年05月 [査読有り]

DOI PubMed

Scopus

62

被引用数

(Scopus)
Hitomi Constraints on the 3.5 keV Line in the Perseus Galaxy Cluster

F. A. Aharonian, H. Akamatsu, F. Akimoto, S. W. Allen, L. Angelini, K. A. Arnaud, M. Audard, H. Awaki, M. Axelsson, A. Bamba, M. W. Bautz, R. D. Blandford, E. Bulbul, L. W. Brenneman, G. V. Brown, E. M. Cackett, M. Chernyakova, M. P. Chiao, P. Coppi, E. Costantini, J. de Plaa, J. -W. den Herder, C. Done, T. Dotani, K. Ebisawa, M. E. Eckart, T. Enoto, Y. Ezoe, A. C. Fabian, C. Ferrigno, A. R. Foster, R. Fujimoto, Y. Fukazawa, A. Furuzawa, M. Galeazzi, L. C. Gallo, P. Gandhi, M. Giustini, A. Goldwurm, L. Gu, M. Guainazzi, Y. Haba, K. Hagino, K. Hamaguchi, I. Harrus, I. Hatsukade, K. Hayashi, T. Hayashi, K. Hayashida, J. Hiraga, A. E. Hornschemeier, A. Hoshino, J. P. Hughes, Y. Ichinohe, R. Iizuka, H. Inoue, S. Inoue, Y. Inoue, K. Ishibashi, M. Ishida, K. Ishikawa, Y. Ishisaki, M. Itoh, M. Iwai, N. Iyomoto, J. S. Kaastra, T. Kallman, T. Kamae, E. Kara, J. Kataoka, S. Katsuda, J. Katsuta, M. Kawaharada, N. Kawai, R. L. Kelley, D. Khangulyan, C. A. Kilbourne, A. L. King, T. Kitaguchi, S. Kitamoto, T. Kitayama, T. Kohmura, M. Kokubun, S. Koyama, K. Koyama, P. Kretschmar, H. A. Krimm, A. Kubota, H. Kunieda, P. Laurent, F. Lebrun, S. -H. Lee, M. A. Leutenegger, O. Limousin, M. Loewenstein, K. S. Long, D. H. Lumb, G. M. Madejski, Y. Maeda, D. Maier, K. Makishima, M. Markevitch, H. Matsumoto, K. Matsushita, D. McCammon, B. R. McNamara, M. Mehdipour, E. D. Miller, J. M. Miller, S. Mineshige, K. Mitsuda, I. Mitsuishi, T. Miyazawa, T. Mizuno, H. Mori, K. Mori, H. Moseley, K. Mukai, H. Murakami, T. Murakami, R. F. Mushotzky, T. Nakagawa, H. Nakajima, T. Nakamori, T. Nakano, S. Nakashima, K. Nakazawa, K. Nobukawa, M. Nobukawa, H. Noda, M. Nomachi, S. L. O'Dell, H. Odaka, T. Ohashi, M. Ohno, T. Okajima, N. Ota, M. Ozaki, F. Paerels, S. Paltani, A. Parmar, R. Petre, C. Pinto, M. Pohl, F. S. Porter, K. Pottschmidt, B. D. Ramsey, C. S. Reynolds, H. R. Russell, S. Safi-Harb, S. Saito, K. Sakai, H. Sameshima, T. Sasaki, G. Sato, K. Sato, R. Sato, M. Sawada, N. Schartel, P. J. Serlemitsos, H. Seta, M. Shidatsu, A. Simionescu, R. K. Smith, Y. Soong, L. Stawarz, Y. Sugawara, S. Sugita, A. E. Szymkowiak, H. Tajima, H. Takahashi, T. Takahashi, S. Takeda, Y. Takei, T. Tamagawa, K. Tamura, T. Tamura, T. Tanaka, Yasuo Tanaka, Yasuyuki Tanaka, M. Tashiro, Y. Tawara, Y. Terada, Y. Terashima, F. Tombesi, H. Tomida, Y. Tsuboi, M. Tsujimoto, H. Tsunemi, T. Tsuru, H. Uchida, H. Uchiyama, Y. Uchiyama, S. Ueda, Y. Ueda, S. Ueno, S. Uno, C. M. Urry, E. Ursino, C. P. de Vries, S. Watanabe, N. Werner, D. R. Wik, D. R. Wilkins, B. J. Williams, S. Yamada, H. Yamaguchi, K. Yamaoka, N. Y. Yamasaki, M. Yamauchi, S. Yamauchi, T. Yaqoob, Y. Yatsu, D. Yonetoku, A. Yoshida, I. Zhuravleva, A. Zoghbi

ASTROPHYSICAL JOURNAL LETTERS 837 ( 1 ) 668 - 672 2017年03月 [査読有り]

　概要を見る

X-ray spectroscopy with Hitomi was expected to resolve the origin of the faint unidentified E approximate to 3.5 keV emission line reported in several low-resolution studies of various massive systems, such as galaxies and clusters, including the Perseus cluster. We have analyzed the Hitomi first-light observation of the Perseus cluster. The emission line expected for Perseus based on the XMM-Newton signal from the large cluster sample under the dark matter decay scenario is too faint to be detectable in the Hitomi data. However, the previously reported 3.5 keV flux from Perseus was anomalously high compared to the sample-based prediction. We find no unidentified line at the reported high flux level. Taking into account the XMM measurement uncertainties for this region, the inconsistency with Hitomi is at a 99% significance for a broad dark matter line and at 99.7% for a narrow line from the gas. We do not find anomalously high fluxes of the nearby faint K line or the Ar satellite line that were proposed as explanations for the earlier 3.5 keV detections. We do find a hint of a broad excess near the energies of high-n transitions of S XVI (E similar or equal to 3.44 keV rest-frame)-a possible signature of charge exchange in the molecular nebula and another proposed explanation for the unidentified line. While its energy is consistent with XMM pn detections, it is unlikely to explain the MOS signal. A confirmation of this interesting feature has to wait for a more sensitive observation with a future calorimeter experiment.

DOI

Scopus

94

被引用数

(Scopus)
福島県の里山に大気沈着した放射性Csの長期変動

金野俊太郎, 大河内博, 勝見尚也, 緒方裕子, 片岡淳, 岸本彩, 岩本康弘, 反町篤行, 床次眞司

分析化学会誌 66 ( 3 ) 17 2017年03月 [査読有り]
Long-term Variations in the Distribution of Radioactive Cs in Plant, Soil, Stream Bottom Sand in a Small Forest in Fukushima Prefecture

Kinno Shuntaro, Okochi Hiroshi, Katsumi Naoya, Ogata Hiroko, Kataoka Jun, Kishimoto Aya, Iwamoto Yasuhiro, Sorimachi Atsuyuki, Tokonami Shinji

BUNSEKI KAGAKU 66 ( 3 ) 163 - 174 2017年03月 [査読有り]

DOI

Scopus

2

被引用数

(Scopus)
Development of TOF-PET using Compton scattering by plastic scintillators

M. Kuramoto, T. Nakamori, S. Kimura, S. Gunji, M. Takakura, J. Kataoka

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 845 668 - 672 2017年02月 [査読有り]

　概要を見る

We propose a time-of-flight (TOF) technique using plastic scintillators which have fast decay time of a few ns for positron emission tomography (PET). While the photoelectric absorption probability of the plastic for 511 keV gamma rays are extremely low due to its small density and effective atomic number, the cross section of Compton scattering is comparable to that of absorption by conventional inorganic scintillators. We thus propose TOF-PET using Compton scattering with plastic scintillators (Compton PET), and performed fundamental experiments towards exploration of the Compton-PET capability. We demonstrated that the plastic scintillators achieved the better time resolution in comparison to LYSO(Ce) and GAGG(Ce) scintillators. In addition we evaluated the depth-of-interaction resolving capability with the plastic scintillators. (C) 2016 Elsevier B.V. All rights reserved.

DOI

Scopus

13

被引用数

(Scopus)
分子イメージングに向けた高解像度コンプトンカメラの開発

岸本彩, 片岡淳, 小出絢子ほか

Nuclear instruments & methods in physics research. Section A 845 ( 11 ) 656 - 659 2017年02月 [査読有り]

DOI

Scopus

30

被引用数

(Scopus)
CTA報告123：全体報告

窪秀利, 手嶋政廣, 戸谷友則, 浅野勝晃, 朝野彰, 井岡邦仁, 石尾一馬, 稲田知大, 井上進, 井上剛志, 井上芳幸, 猪目祐介, 岩村由樹, 内山泰伸, 大石理子, 大岡秀行, 大平豊, 岡崎奈緒, 奥村曉, 折戸玲子, 加賀谷美佳, 格和純, 片岡淳, 片桐秀明, 勝倉大輔, 勝田哲, 加藤翔, 神本匠, 川中宣太, 木坂将大, 木村颯一朗, 櫛田淳子, 久門拓, 黒田隼人, 郡司修一, 郡和範, 小山志勇, 齋藤隆之, 榊直人, 櫻井駿介, 佐々井義矩, 佐野栄俊, 澤田真理, 柴田徹, 砂田裕志, 関崎晴仁, 高田順平, 高橋慶太郎, 高橋知也, 高橋弘充, 高橋光成, 田島宏康, 立原研悟, 田中周太, 田中孝明, 田中真伸, 田中康之, 種田裕貴, 千川道幸, 辻本晋平, 鶴剛, 寺田幸功, 當真賢二, 門叶冬樹, 内藤統也, 中嶋大輔, 長瀧重博, 中村裕樹, 中森健之, 中山和則, 永吉勤, 西嶋恭司, 西山楽, 野崎誠也, 野田浩司, 早川貴敬, 林克洋, 林田将明, 原敏, 馬場彩, 日高直哉, 平子丈, 廣島渚, 広谷幸一, 深沢泰司, 深見哲志, 福井康雄, 藤田裕, 増田周, 松本浩典, 三浦知佳, 水野恒史, 村石浩, 村瀬孔大, 森浩二, 柳田昭平, 山崎了, 山本常夏, 山本宏昭, 吉池智史, 吉越貴紀, 吉田篤正, 吉田龍生, 李健, 李兆衡

日本物理学会講演概要集 72.2 355 - 355 2017年

DOI CiNii
CTA報告125：CTA大口径望遠鏡初号機の焦点面検出器建設状況

櫻井駿介, 折戸玲子, 片岡淳, 片桐秀明, 木村颯一朗, 櫛田淳子, 窪秀利, 郡司修一, 小山志勇, 今野裕介, 齋藤隆之, 池野正弘, 澤田真理, 砂田裕志, 高橋光成, 田中真伸, 辻本晋平, 手嶋政廣, 寺田幸功, 門叶冬樹, 中嶋大輔, 中森健之, 稲田知大, 永吉勤, 西嶋恭司, 西山楽, 野崎誠也, 林田将明, 馬場彩, 平子丈, 深見哲志, 増田周, 山本常夏, 猪目祐介, 吉田龍生, Hadasch D., Mazin D., 他CTA-Japan consortium, 岩村由樹, 内田智久, 大岡秀行, 奥村曉, 岡崎奈緒

日本物理学会講演概要集 72 ( 0 ) 360 - 360 2017年

DOI CiNii
CTA 報告 126：CTA大口径望遠鏡焦点面検出器の改良と較正

砂田裕志, 折戸玲子, 片岡淳, 片桐秀明, 木村颯一朗, 櫛田淳子, 窪秀利, 郡司修一, 小山志勇, 今野裕介, 齋藤隆之, 池野正弘, 澤田真理, 櫻井駿介, 高橋光成, 田中真伸, 辻本晋平, 手嶋政廣, 寺田幸功, 門叶冬樹, 中嶋大輔, 中森健之, 稲田知大, 永吉勤, 西嶋恭司, 西山楽, 野崎誠也, 林田将明, 馬場彩, 平子丈, 深見哲志, 増田周, 山本常夏, 猪目祐介, 吉田龍生, Hadasch D., Mazin D., 他CTA-Japan consortium, 岩村由樹, 内田智久, 大岡秀行, 奥村曉, 岡崎奈緒

日本物理学会講演概要集 72 ( 0 ) 361 - 361 2017年

DOI CiNii
Secondary-electron-bremsstrahlung imaging for proton therapy

Yamaguchi Mitsutaka, Nagao Yuto, Ando Koki, Yamamoto Seiichi, Toshito Toshiyuki, Kataoka Jun, Kawachi Naoki

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 833 199-207 - 207 2016年10月 [査読有り]

DOI

Scopus

40

被引用数

(Scopus)
Development and verification of signal processing system of avalanche photo diode for the active shields onboard ASTRO-H

M. Ohno, T. Kawano, I. Edahiro, H. Shirakawa, N. Ohashi, C. Okada, S. Habata, J. Katsuta, Y. Tanaka, H. Takahashi, T. Mizuno, Y. Fukazawa, H. Murakami, S. Kobayashi, K. Miyake, K. Ono, Y. Kato, Y. Furuta, Y. Murota, K. Okuda, Y. Wada, K. Nakazawa, T. Mimura, J. Kataoka, Y. Ichinohe, Y. Uchida, M. Katsuragawa, H. Yoneda, G. Sato, R. Sato, M. Kawaharada, A. Harayama, H. Odaka, K. Hayashi, M. Ohta, S. Watanabe, M. Kokubun, T. Takahashi, S. Takeda, M. Kinoshita, K. Yamaoka, H. Tajima, Y. Yatsu, H. Uchiyama, S. Saito, T. Yuasa, K. Makishima

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 831 410 - 414 2016年09月

　概要を見る

The hard X-ray Imager and Soft Gamma-ray Detector onboard ASTRO-H demonstrate high sensitivity to hard X-ray (5–80 keV) and soft gamma-rays (60–600 keV), respectively. To reduce the background, both instruments are actively shielded by large, thick Bismuth Germanate scintillators. We have developed the signal processing system of the avalanche photodiode in the BGO active shields and have demonstrated its effectiveness after assembly in the flight model of the HXI/SGD sensor and after integration into the satellite. The energy threshold achieved is about 150 keV and anti-coincidence efficiency for cosmic-ray events is almost 100%. Installed in the BGO active shield, the developed signal processing system successfully reduces the room background level of the main detector.

DOI

Scopus

6

被引用数

(Scopus)
CALET Upper Limits on X-Ray and Gamma-Ray Counterparts of GW151226”

Adriani, O, Akaike, Y, Asano, K, Asaoka, Y, Bagliesi, M. G, Bigongiari, G, Binns, W. R, Bonechi, S, Bongi, M, Brogi, P, Buckley, J. H, Cannady, N, Castellini, G, Checchia, C, Cherry, M. L, Collazuol, G, Di Felice, V, Ebisawa, K, Fuke, H, Guzik, T. G, Hams, T, Hareyama, M, Hasebe, N, Hibino, K, Ichimura, M, Ioka, K, Ishizaki, W, Israel, M. H, Javaid, A, Kasahara, K, Kataoka, J, Kataoka, R, Katayose, Y, Kato, C, Kawanaka, N, Kawakubo, Y, Kitamura, H, Krawczynski, H. S, Krizmanic, J. F, Kuramata, S, Lomtadze, T, Maestro, P, Marrocchesi, P. S, Messineo, A. M, Mitchell, J. W, Miyake, S, Mizutani, K, Moiseev, A. A, Mori, K, Mori, M, Mori, N, Motz, H. M, Munakata, K, Murakami, H, Nakagawa, Y. E, Nakahira, S, Nishimura, J, Okuno, S, Ormes, J. F, Ozawa, S, Pacini, L, Palma, F, Papini, P, Penacchioni, A. V, Rauch, B. F, Ricciarini, S, Sakai, K, Sakamoto, T, Sasaki, M, Shimizu, Y, Shiomi, A, Sparvoli, R, Spillantini, P, Stolzi, F, Takahashi, I, Takayanagi, M, Takita, M, Tamura, T, Tateyama, N, Terasawa, T, Tomida, H, Torii, S, Tsunesada, Y, Uchihori, Y, Ueno, S, Vannuccini, E, Wefel, J. P, Yamaoka, K, Yanagita, S, Yoshida, A, Yoshida, K, Yuda, T

829 ( 1 ) 2016年09月

DOI

Scopus

34

被引用数

(Scopus)
The Si/CdTe semiconductor camera of the ASTRO-H Hard X-ray Imager (HXI)

Goro Sato, Kouichi Hagino, Shin Watanabe, Kei Genba, Atsushi Harayama, Hironori Kanematsu, Jun Kataoka, Miho Katsuragawa, Madoka Kawaharada, Shogo Kobayashi, Motohide Kokubun, Yoshikatsu Kuroda, Kazuo Makishima, Kazunori Masukawa, Taketo Mimura, Katsuma Miyake, Hiroaki Murakami, Toshio Nakano, Kazuhiro Nakazawa, Hirofumi Noda, Hirokazu Odaka, Mitsunobu Onishi, Shinya Saito, Rie Sato, Tamotsu Sato, Hiroyasu Tajima, Hiromitsu Takahashi, Tadayuki Takahashi, Shin'ichiro Takeda, Takayuki Yuasa

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 831 235 - 241 2016年09月 [査読有り]

　概要を見る

The Hard X-ray Imager (HXI) is one of the instruments onboard the ASTRO-H mission [14 to be launched in early 2016. The HXI is the focal plane detector of the hard X-ray reflecting telescope that covers an energy range from 5 to 80 keV. It will execute observations of astronomical objects with a sensitivity for point sources as faint as 1/100,000 of the Crab nebula at > 10 keV. The HXI camera - the imaging part of the HXI - is realized by a hybrid semiconductor detector system that consists of silicon (Si) and cadmium telluride (CdTe) semiconductor detectors. Here, we present the final design of the HXI camera and report on the development of the flight model. The camera is composed of four layers of Double-sided Silicon Strip Detectors (DSSDs) and one layer of CdTe Double -sided Strip Detector (CdTeDSD), each with an imaging area of 32 mm x 32 mm. The strip pitch of the Si and CdTe sensors is 250 pm, and the signals from all 1280 strips are processed by 40 Application Specified Integrated Circuits (ASICs) developed for the HXI. The five layers of sensors are vertically stacked with a 4 mm spacing to increase the detection efficiency. The thickness of the sensors is 0.5 mm for the Si, and 0.75 mm for the CdTe. In this configuration, soft X-ray photons will be absorbed in the Si part, while hard X-ray photons will go through the Si part and will be detected in the CdTe part. The design of the sensor trays, peripheral circuits, power connections, and readout schemes are also described. The flight models of the HXI camera have been manufactured, tested and installed in the HXI instrument and then on the satellite. (C) 2016 Elsevier B.V. All rights reserved.

DOI

Scopus

28

被引用数

(Scopus)
Performance evaluation of newly developed SrI2(Eu) scintillator

M. Takabe, A. Kishimoto, J. Kataoka, S. Sakuragi, Y. Yamasaki

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 831 ( 21 ) 260 - 264 2016年09月 [査読有り]

　概要を見る

The development of europium-doped strontium iodide (SrI2(Eu)) has attracted considerable attention, because of its excellent material properties as regards gamma -ray scintillator applications. These include its excellent energy resolution, high light output (>80, 000 ph/MeV), and high effective atomic number (Z=49). Here we report on the performance of 0 1 in x 1 in SrI2(Eu) cylindrical crystals newly fabricated by Union Materials Inc. In this study, we measured the energy resolution and light output at 10 C temperature intervals between 40 and 40 degrees C, using an optically coupled 2 -in photomultiplier tube (PMT) (Super Bialkali, Hamamatsu). The SrI2(Eu) light output increased by 0.12%/degrees C as the temperature decreased. At 40 C, we obtained the optimal energy resolution recording 2.91 0.02% full width at half maximum (FWHM) for 662 keV gamma rays measured with 137Cs. For comparison, we also measured the same crystal using both a large-area (19 x 19 mm2) avalanche photodiode detector (APD) and 8 x 8 multi -pixel photon counter (MPPC) arrays of 3 x 3 mm2 pixels. The energy resolutions of 2.94 + 0.02%, 3.14 + 0.06% and 3.99 + 0.01% were obtained using PMT, APD, and MPPC, respectively, as measured at 20 degrees C. We also measured the inherent background of SrI2(Eu) in a cave composed of Cu Pb blocks with their thickness of 5-10 cm confirming that Srl2(Eu) has an extremely low inherent background radiation. In this study, we have shown that SrI2(Eu) is a promising scintillator that can be utilized for radiation measurements incorporating low-energy X-rays to high-energy gamma rays, and can thus be applied in various medical, industrial, and environmental treatment fields in the near future. (C) 2016 Elsevier B.V. All rights reserved.

DOI

Scopus

13

被引用数

(Scopus)
物質中での放射性各種3次元分布を見積もる新規手法の提案

岩本康弘, 片岡淳, 岸本彩ほか

Nuclear Instruments and Methods in Physics Research Section A 831 ( 21 ) 295 - 300 2016年09月 [査読有り]

DOI

Scopus

10

被引用数

(Scopus)
携帯型コンプトンカメラを用いたリアルタイム即発ガンマ線イメージングの初期実証

多屋隆紀, 片岡淳, 岸本彩ほか

Nuclear Instruments and Methods in Physics Research Section A 831 ( 21 ) 355 - 361 2016年09月 [査読有り]

DOI

Scopus

27

被引用数

(Scopus)
放射性物質を可視化するコンプトンカメラ

片岡淳, 武田伸一郎, 高橋忠幸

光学（日本光学会・学会誌）出版中 ( 8 ) 289 - 299 2016年08月 [査読有り] [招待有り]

CiNii
NuSTAR衛星によるTeVブレーザーMrk421からの逆コンプトン散乱放射の発見

片岡淳

The Astrophysical Journal 827 ( 1 ) 55 2016年08月 [査読有り]

DOI

Scopus

24

被引用数

(Scopus)
The quiescent intracluster medium in the core of the Perseus cluster

Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Naohisa Anabuki, Lorella Angelini, Keith Arnaud, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall Bautz, Roger Blandford, Laura Brenneman, Gregory V. Brown, Esra Bulbul, Edward Cackett, Maria Chernyakova, Meng Chiao, Paolo Coppi, Elisa Costantini, Jelle De Plaa, Jan Willem Den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Junko Hiraga, Ann Hornschemeier, Akio Hoshino, John Hughes, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Kazunori Ishibashi, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masayuki Itoh, Naoko Iyomoto, Jelle Kaastra, Timothy Kallman, Tuneyoshi Kamae, Erin Kara, Jun Kataoka, Satoru Katsuda, Junichiro Katsuta, Madoka Kawaharada, Nobuyuki Kawai, Richard Kelley, Dmitry Khangulyan, Caroline Kilbourne, Ashley King, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Shu Koyama, Katsuji Koyama, Peter Kretschmar, Hans Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, François Lebrun, Shiu Hang Lee, Maurice Leutenegger, Olivier Limousin, Michael Loewenstein, Knox S. Long, David Lumb, Grzegorz Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch

Nature 535 ( 7610 ) 117 - 121 2016年07月

　概要を見る

Clusters of galaxies are the most massive gravitationally bound objects in the Universe and are still forming. They are thus important probes of cosmological parameters and many astrophysical processes. However, knowledge of the dynamics of the pervasive hot gas, the mass of which is much larger than the combined mass of all the stars in the cluster, is lacking. Such knowledge would enable insights into the injection of mechanical energy by the central supermassive black hole and the use of hydrostatic equilibrium for determining cluster masses. X-rays from the core of the Perseus cluster are emitted by the 50-million-kelvin diffuse hot plasma filling its gravitational potential well. The active galactic nucleus of the central galaxy NGC 1275 is pumping jetted energy into the surrounding intracluster medium, creating buoyant bubbles filled with relativistic plasma. These bubbles probably induce motions in the intracluster medium and heat the inner gas, preventing runaway radiative cooling - a process known as active galactic nucleus feedback. Here we report X-ray observations of the core of the Perseus cluster, which reveal a remarkably quiescent atmosphere in which the gas has a line-of-sight velocity dispersion of 164 ± 10 kilometres per second in the region 30-60 kiloparsecs from the central nucleus. A gradient in the line-of-sight velocity of 150 ± 70 kilometres per second is found across the 60-kiloparsec image of the cluster core. Turbulent pressure support in the gas is four per cent of the thermodynamic pressure, with large-scale shear at most doubling this estimate. We infer that a total cluster mass determined from hydrostatic equilibrium in a central region would require little correction for turbulent pressure.

DOI

Scopus

362

被引用数

(Scopus)
Development of a high resolution gamma camera system using finely grooved GAGG scintillator

Seiichi Yamamoto, Jun Kataoka, Tsubasa Oshima, Yoshimune Ogata, Tadashi Watabe, Hayato Ikeda, Yasukazu Kanai, Jun Hatazawa

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 821 28 - 33 2016年06月 [査読有り]

　概要を見る

High resolution gamma cameras require small pixel scintillator blocks with high light output. However, manufacturing a small pixel scintillator block is difficult when the pixel size becomes small. To solve this limitation, we developed a high resolution gamma camera system using a finely grooved Ce-doped Gd3Al2Ga3O12 (GAGG) plate. Our gamma camera's detector consists of a 1-mm-thick finely grooved GAGG plate that is optically coupled to a 1-in. position sensitive photomultiplier tube (PSPMT). The grooved GAGG plate has 0.2 x 0.2 mm pixels with 0.05-mm wide slits (between the pixels) that were manufactured using a dicing saw. We used a Hamamatsu PSPMT with a 1-in. square high quantum efficiency (HQE) PSPMT (R8900-100-C12). The energy resolution for the Co-57 gamma photons (122 keV) was 18.5% FWHM. The intrinsic spatial resolution was estimated to be 0.7-mm FVVHM. With a 0.5-mm diameter pinhole collimator mounted to its front, we achieved a high resolution, small field-of-view gamma camera. The system spatial resolution for the Co-57 gamma photons was 1.0-mm FWHM, and the sensitivity was 0.0025%, 10 mm from the collimator surface. The Tc-99m HMDP administered mouse images showed the fine structures of the mouse body's parts. Our developed high resolution small pixel GAGG gamma camera is promising for such small animal imaging. (C) 2016 Elsevier B.V. All rights reserved.

DOI

Scopus

24

被引用数

(Scopus)
X線シャドウを用いた分子雲CO-H2比の変換係数測定

祖父江義明, 片岡淳

Publications of the Astronomical Society of Japan 68 ( 3 ) L8 2016年06月 [査読有り]

DOI

Scopus

7

被引用数

(Scopus)
銀河中心の爆発モデルのNPS構造理解への応用

祖父江義明, 羽部朝男, 片岡淳

Monthly notices of the Royal Astronomical Society 459 ( 1 ) 108 - 120 2016年06月 [査読有り]

DOI

Scopus

24

被引用数

(Scopus)
THE FIRST FERMI LAT SUPERNOVA REMNANT CATALOG

F. Acero, M. Ackermann, M. Ajello, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, R. Bellazzini, E. Bissaldi, R. D. Blandford, E. D. Bloom, R. Bonino, E. Bottacini, T. J. Brandt, J. Bregeon, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, R. Caputo, M. Caragiulo, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, A. Chekhtman, J. Chiang, G. Chiaro, S. Ciprini, R. Claus, J. M. Cohen, J. Cohen-Tanugi, L. R. Cominsky, B. Condon, J. Conrad, S. Cutini, F. D'Ammando, A. De Angelis, F. De Palma, R. Desiante, S. W. Digel, L. Di Venere, P. S. Drell, A. Drlica-Wagner, C. Favuzzi, E. C. Ferrara, A. Franckowiak, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, G. A. Gomez-Vargas, I. A. Grenier, M. H. Grondin, L. Guillemot, S. Guiriec, M. Gustafsson, D. Hadasch, A. K. Harding, M. Hayashida, E. Hays, J. W. Hewitt, A. B. Hill, D. Horan, X. Hou, G. Iafrate, T. Jogler, G. Jóhannesson, A. S. Johnson, T. Kamae, H. Katagiri, J. Kataoka, J. Katsuta, M. Kerr, J. Knödlseder, D. Kocevski, M. Kuss, H. Laffon, J. Lande, S. Larsson, L. Latronico, M. Lemoine-Goumard, J. Li, L. Li, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, J. Magill, S. Maldera, M. Marelli, M. Mayer

Astrophysical Journal, Supplement Series 224 ( 1 ) 2016年05月

　概要を見る

To uniformly determine the properties of supernova remnants (SNRs) at high energies, we have developed the first systematic survey at energies from 1 to 100 GeV using data from the Fermi Large Area Telescope (LAT). Based on the spatial overlap of sources detected at GeV energies with SNRs known from radio surveys, we classify 30 sources as likely GeV SNRs. We also report 14 marginal associations and 245 flux upper limits. A mock catalog in which the positions of known remnants are scrambled in Galactic longitude allows us to determine an upper limit of 22% on the number of GeV candidates falsely identified as SNRs. We have also developed a method to estimate spectral and spatial systematic errors arising from the diffuse interstellar emission model, a key component of all Galactic Fermi LAT analyses. By studying remnants uniformly in aggregate, we measure the GeV properties common to these objects and provide a crucial context for the detailed modeling of individual SNRs. Combining our GeV results with multiwavelength (MW) data, including radio, X-ray, and TeV, we demonstrate the need for improvements to previously sufficient, simple models describing the GeV and radio emission from these objects. We model the GeV and MW emission from SNRs in aggregate to constrain their maximal contribution to observed Galactic cosmic rays.

DOI

Scopus

221

被引用数

(Scopus)
Observation of polarized hard X-ray emission from the Crab by the PoGOLite Pathfinder

Chauvin M, Floren H. -G, Jackson M, Kamae T, Kawano T, Kiss M, Kole M, Mikhalev V, Moretti E, Olofsson G, Rydstrom S, Takahashi H, Iyudin A, Arimoto M, Fukazawa Y, Kataoka J, Kawai N, Mizuno T, Ryde F, Tajima H, Takahashi T, Pearce M

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 456 ( 1 ) L84 - L88 2016年02月 [査読有り]

DOI

Scopus

20

被引用数

(Scopus)
19pCA-10 プラスチックシンチレータを用いたコンプトン散乱型TOF-PET装置の基礎開発

倉本南, 中森健之, 木村沙也香, 郡司修一, 高倉美華, 小野寺拓也, 片岡淳

日本物理学会講演概要集 71 101 - 101 2016年

DOI CiNii
X線衛星「ひとみ(ASTRO-H)」搭載の硬X線撮像検出器(HXI)の軌道上動作

中澤知洋, 高橋忠幸, 国分紀秀, 渡辺伸, 佐藤悟朗, 太田方之, 萩野浩一, 佐藤理江, Lee Herman, 能町正治, 米徳大輔, 田中孝明, 榎戸輝揚, 寺田幸功, 内山秀樹, 谷津洋一, 一戸悠人, 野田博文, 田島宏康, 山岡和貴, 林克洋, 深沢泰司, 水野恒史, 大野雅功, 高橋弘充, 中森健之, 内山泰伸, 斉藤新也, 牧島一夫, 湯浅孝行, 中野俊男, 片岡淳, Francois Lebrun, Andrea Goldwurm, Olivier Limousin, Philippe Laurent, Daniel Maier, 武田伸一郎, 小高裕和, その他HXIチーム

日本物理学会講演概要集 71 370 - 370 2016年

　概要を見る

本年2月17日に打ち上げられ3月26日に通信途絶したX線天文衛星「ひとみ」には、5-80 keVを2分角で撮像分光する硬X線撮像検出器(HXI)が搭載されていた。打ち上げ後、伸展式光学ベンチの展開を経て、3月8日よりHXI検出器の立ち上げを始めた。3月14日は2台のHXIが立ち上がり、観測を開始した。軌道上での性能は、エネルギー分解能を含め地上試験と一致し、無事に立ち上げに成功した。天体の撮像とスペクトルも取得できている。軌道上のバックグラウンドも40 keV以下ではほぼ期待通りの性能を発揮した。この結果について報告する。

DOI CiNii
X線衛星「ひとみ(ASTRO-H)」搭載軟ガンマ線検出器(SGD)の軌道上動作

渡辺伸, 田島宏康, 深沢泰司, 一戸悠人, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 勝田隼一郎, 北口貴雄, 国分紀秀, Goldwurm Andrea, 斉藤新也, 佐藤悟朗, 佐藤理江, 高橋忠幸, 高橋弘充, 武田伸一郎, 田中孝明, 田中康之, 寺田幸功, 中澤知洋, 中野俊男, 中森健之, 野田博文, 萩野浩一, 林克洋, Blandford Roger, 牧島一夫, Madejski Grzegorz, 水野恒史, 森國城, 谷津陽一, 山岡和貴, 湯浅孝行, 米徳大輔, Laurent Philippe, Limousin Olivier, Lebrun François, ほかSGDチーム

日本物理学会講演概要集 71 371 - 371 2016年

　概要を見る

2016年2月17日に打ち上げられたX線衛星「ひとみ」(ASTRO-H)に搭載された軟ガンマ線検出器(Soft Gamma-ray Detector:SGD)の軌道動作実績について報告する。SGDは、3月15日より順次、センサーの立ち上げを行い、通信途絶となった3月26日まで、機能的には正常に動作させることができた。一部の天体からのガンマ線信号の取得に成功し、高感度ガンマ線観測を行う上で重要となる軌道上バックグランドのデータを得た。SGDで初めて実現したSi/CdTe半導体コンプトンカメラで得られたこれらのデータについて、報告を行う。

DOI CiNii
The ASTRO-H (Hitomi) X-ray astronomy satellite

Tadayuki Takahashi, Motohide Kokubun, Kazuhisa Mitsuda, Richard Kelley, Takaya Ohashi, Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steve Allen, Naohisa Anabuki, Lorella Angelini, Keith Arnaud, Makoto Asai, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Philipp Azzarello, Chris Baluta, Aya Bamba, Nobutaka Bando, Marshall Bautz, Thomas Bialas, Roger Blandford, Kevin Boyce, Laura Brenneman, Greg Brown, Esra Bulbul, Edward Cackett, Edgar Canavan, Maria Chernyakova, Meng Chiao, Paolo Coppi, Elisa Costantini, Jelle De Plaa, Jan Willem Den Herder, Michael DiPirro, Chris Done, Tadayasu Dotani, John Doty, Ken Ebisawa, Megan Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew Fabian, Carlo Ferrigno, Adam Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi Gallo, Poshak Gandhi, Kirk Gilmore, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Daniel Haas, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Atsushi Harayama, Ilana Harrus, Isamu Hatsukade, Takayuki Hayashi, Katsuhiro Hayashi, Kiyoshi Hayashida, Junko Hiraga, Kazuyuki Hirose, Ann Hornschemeier, Akio Hoshino, John Hughes, Yuto Ichinohe, Ryo Iizuka, Yoshiyuki Inoue, Hajime Inoue, Kazunori Ishibashi, Manabu Ishida, Kumi Ishikawa, Kosei Ishimura, Yoshitaka Ishisaki, Masayuki Itoh, Naoko Iwata, Naoko Iyomoto, Chris Jewell, Jelle Kaastra, Timothy Kallman, Tuneyoshi Kamae, Erin Kara, Jun Kataoka, Satoru Katsuda, Junichiro Katsuta, Madoka Kawaharada, Nobuyuki Kawai, Taro Kawano, Shigeo Kawasaki, Dmitry Khangulyan, Caroline Kilbourne, Mark Kimball, Ashley King

Proceedings of SPIE - The International Society for Optical Engineering 9905 2016年

　概要を見る

The Hitomi (ASTRO-H) mission is the sixth Japanese X-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E > 2 keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decades in energy from soft X-rays to gamma-rays. After a successful launch on 2016 February 17, the spacecraft lost its function on 2016 March 26, but the commissioning phase for about a month provided valuable information on the on-board instruments and the spacecraft system, including astrophysical results obtained from first light observations. The paper describes the Hitomi (ASTRO-H) mission, its capabilities, the initial operation, and the instruments/spacecraft performances confirmed during the commissioning operations for about a month.

DOI

Scopus

81

被引用数

(Scopus)
The hard X-ray imager (HXI) onboard ASTRO-H

Kazuhiro Nakazawa, Goro Sato, Motohide Kokubun, Teruaki Enoto, Yasushi Fukazawa, Kouichi Hagino, Atsushi Harayama, Katsuhiro Hayashi, Jun Kataoka, Junichiro Katsuta, Philippe Laurent, Francois Lebrung, Olivier Limousin, Kazuo Makishima, Tsunefumi Mizuno, Kunishiro Mori, Takeshi Nakamori, Toshio Nakano, Hirofumi Noda, Hirokazu Odaka, Masanori Ohno, Masayuki Ohta, Shinya Saito, Rie Sato, Hiroyasu Tajima, Hiromitsu Takahashi, Tadayuki Takahashi, Shin'ichiro Takeda, Yukikatsu Terada, Hideki Uchiyama, Yasunobu Uchiyama, Shin Watanabe, Kazutaka Yamaoka, Yoichi Yatsu, Takayuki Yuasa

SPACE TELESCOPES AND INSTRUMENTATION 2016: ULTRAVIOLET TO GAMMA RAY 9905 2016年 [査読有り]

　概要を見る

Hitomi X-ray observatory launched in 17 February 2016 had a hard X-ray imaging spectroscopy system made of two hard X-ray imagers (HXIs) coupled with two hard X-ray telescopes (HXTs). With 12 m focal length, they provide fine (2' half-power diameter; HPD) imaging spectroscopy at 5 to 80 keV. The HXI main imagers are made of 4 layers of Si and a CdTe semiconductor double-sided strip detectors, stacked to enhance detection efficiency as well as to enable photon interaction-depth sensing. Active shield made of 9 BGO scintillators surrounds the imager to provide with low background. Following the deployment of the Extensible Optical Bench (EOB) on 28 February, the HXI was gradually turned on. Two imagers successfully started observation on 14 March, and was operational till the incident lead to Hitomo loss, on 26 March. All detector channels, 1280 ch of imager and 11 channel of active shields and others each, worked well and showed performance consistent with those seen on ground. From the first light observation of G21.5-0.9 and the following Crab observations, 5 80 keV energy coverage and good detection efficiency were confirmed. With blank sky observations, we checked our background level. In some geomagnetic region, strong background continuum, presumably caused by trapped electron with energy similar to 100 keV, is seen. But by cutting the high-background time-intervals, the background became significantly lower, typically with 1-3x10(-4) counts s(-1) keV(-1) cm(-2) (here cm(2) is shown with detector geometrical area). Above 30 keV, line and continuum emission originating from activation of CdTe was significantly seen, though the level of 1-4x10(-4) counts s(-1) keV(-1) cm(-2) is still comparable to those seen in NuSTAR. By comparing the effective area and background rate, preliminary analysis shows that the HXI had a statistical sensitivity similar to NuSTAR for point sources, and more than twice better for largely extended sources.

DOI

Scopus

13

被引用数

(Scopus)
2FHL: THE SECOND CATALOG OF HARD FERMI-LAT SOURCES

Ackermann, M, Ajello, M, Atwood, W. B, Baldini, L, Ballet, J, Barbiellini, G, Bastieri, D, Gonzalez, J. Becerra, Bellazzini, R, Bissaldi, E, Blandford, R. D, Bloom, E. D, Bonino, R, Bottacini, E, Brandt, T. J, Bregeon, J, Bruel, P, Buehler, R, Buson, S, Caliandro, G. A, Cameron, R. A, Caputo, R, Caragiulo, M, Caraveo, P. A, Cavazzuti, E, Cecchi, C, Charles, E, Chekhtman, A, Cheung, C. C, Chiang, J, Chiaro, G, Ciprini, S, Cohen, J. M, Cohen-Tanugi, J, Cominsky, L. R, Conrad, J, Cuoco, A, Cutini, S, D'Ammando, F, de Angelis, A, de Palma, F, Desiante, R, Di Mauro, M, Di Venere, L, Dominguez, A, Drell, P. S, Favuzzi, C, Fegan, S. J, Ferrara, E. C, Focke, W. B, Fortin, P, Franckowiak, A, Fukazawa, Y, Funk, S, Furniss, A. K, Fusco, P, Gargano, F, Gasparrini, D, Giglietto, N, Giommi, P, Giordano, F, Giroletti, M, Glanzman, T, Godfrey, G, Grenier, I. A, Grondin, M. -H, Guillemot, L, Guiriec, S, Harding, A. K, Hays, E, Hewitt, J. W, Hill, A. B, Horan, D, Iafrate, G, Hartmann, Dieter, Jogler, T, Johannesson, G, Johnson, A. S, Kamae, T, Kataoka, J, Knoedlseder, J, Kuss, M, La Mura, G, Larsson, S, Latronico, L, Lemoine-Goumard, M, Li, J, Li, L, Longo, F, Loparco, F, Lott, B, Lovellette, M. N, Lubrano, P, Madejski, G. M, Maldera, S, Manfreda, A, Mayer, M, Mazziotta, M. N, Michelson, P. F, Mirabal, N, Mitthumsiri, W, Mizuno, T, Moiseev, A. A, Monzani, M. E, Morselli, A, Moskalenko, I. V, Murgia, S, Nuss, E, Ohsugi, T, Omodei, N, Orienti, M, Orlando, E, Ormes, J. F, Paneque, D, Perkins, J. S, Pesce-Rollins, M, Petrosian, V, Piron, F, Pivato, G, Porter, T. A, Raino, S, Rando, R, Razzano, M, Razzaque, S, Reimer, A, Reimer, O, Reposeur, T, Romani, R. W, Sanchez-Conde, M, Parkinson, P. M. Saz, Schmid, J, Schulz, A, Sgro, C, Siskind, E. J, Spada, F, Spandre, G, Spinelli, P, Suson, D. J, Tajima, H, Takahashi, H, Takahashi, M, Takahashi, T, Thayer, J. B, Thompson, D. J, Tibaldo, L, Torres, D. F, Tosti, G, Troja, E, Vianello, G, Wood, K. S, Wood, M, Yassine, M, Zaharijas, G, Zimmer, S

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES 222 ( 1 ) 2016年01月 [査読有り]

　概要を見る

We present a catalog of sources detected above 50 GeV by the Fermi-Large Area Telescope (LAT) in 80 months of data. The newly delivered Pass. 8 event-level analysis allows the detection and characterization of sources in the 50 GeV-2 TeV energy range. In this energy band, Fermi-LAT. has detected 360 sources, which constitute the second catalog of hard Fermi-LAT. sources (2FHL). The improved angular resolution enables the precise localization of point sources (similar to 1.' 7 radius at 68% C.L.) and the detection and characterization of spatially extended sources. We find that 86% of the sources can be associated with counterparts at other wavelengths, of which the majority (75%) are active galactic nuclei and the rest (11%) are Galactic sources. Only 25% of the 2FHL sources have been previously detected by Cherenkov telescopes, implying that the 2FHL provides a reservoir of candidates to be followed up at very high energies. This work closes the energy gap between the observations performed at GeV energies by Fermi-LAT. on orbit and the observations performed at higher energies by Cherenkov telescopes from the ground.

DOI

Scopus

228

被引用数

(Scopus)
The soft gamma-ray detector (SGD) onboard ASTRO-H

Watanabe Shin, Tajima Hiroyasu, Fukazawa Yasushi, Blandford Roger, Enoto Teruaki, Goldwurm Andrea, Hagino Kouichi, Hayashi Katsuhiro, Ichinohe Yuto, Kataoka Jun, Katsuta Junichiro, Kitaguchi Takao, Kokubun Motohide, Laurent Philippe, Lebrun Francois, Limousin Olivier, Madejski Grzegorz M, Makishima Kazuo, Mizunoe Tsunefumi, Mori Kunishiro, Nakamori Takeshi, Nakano Toshio, Nakazawa Kazuhiro, Noda Hirofumi, Odaka Hirokazu, Ohno Masanori, Ohta Masayuki, Saito Shinya, Sato Goro, Sato Rie, Takeda Shin'ichiro, Takahashi Hiromitsu, Takahashi Tadayuki, Tanaka Takaaki, Tanaka Yasuyuki, Terada Yukikatsu, Uchiyama Hideki, Uchiyama Yasunobu, Yamaoka Kazutaka, Yatsu Yoichi, Yonetoku Daisuke, Yuasa Takayuki

SPACE TELESCOPES AND INSTRUMENTATION 2016: ULTRAVIOLET TO GAMMA RAY 9905 2016年 [査読有り]

DOI

Scopus

13

被引用数

(Scopus)
Observation of polarized hard X-ray emission from the Crab by the PoGOLite Pathfinder

M. Chauvin, H. G. Florén, M. Jackson, T. Kamae, T. Kawano, M. Kiss, M. Kole, V. Mikhalev, E. Moretti, G. Olofsson, S. Rydström, H. Takahashi, A. Iyudin, M. Arimoto, Y. Fukazawa, J. Kataoka, N. Kawai, T. Mizuno, F. Ryde, H. Tajima, T. Takahashi, M. Pearce

Monthly Notices of the Royal Astronomical Society: Letters 456 ( 1 ) L84 - L88 2016年

　概要を見る

We have measured the linear polarization of hard X-ray emission from the Crab in a previously unexplored energy interval, 20-120 keV. The introduction of two new observational parameters, the polarization fraction and angle stands to disentangle geometrical and physical effects, thereby providing information on the pulsar wind geometry and magnetic field environment. Measurements are conducted using the PoGOLite Pathfinder - a balloon-borne polarimeter. Polarization is determined by measuring the azimuthal Compton scattering angle of incident X-rays in an array of plastic scintillators housed in an anticoincidence well. The polarimetric response has been characterized prior to flight using both polarized and unpolarized calibration sources. We address possible systematic effects through observations of a background field. The measured polarization fraction for the integrated Crab light curve is 18.4+9.8 -10.6 per cent, corresponding to an upper limit (99 per cent credibility) of 42.4 per cent, for a polarization angle of (149.2 ± 16.0)°.

DOI

Scopus

20

被引用数

(Scopus)
Development of a high-precision color gamma-ray image sensor based on TSV-MPPC and diced scintillator arrays

T. Oshima, J. Kataoka, A. Kishimoto, T. Fujita, Y. Kurei, T. Nishiyama, H. Morita, S. Yamamoto, K. Ogawa

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 803 8 - 14 2015年12月 [査読有り]

　概要を見る

We developed a high precision color gamma ray image sensor with fine spatial resolution that is cost effective, widely applicable, and very sensitive, by using a diced Ce-doped Gd3Al2Ga3O12 (Ce:CACC.) scintillator array coupled with a 3.0 x 3.0 mm(2)/pixel 8 x 8 MPPC-array. The proposed image sensor can measure the energy of individual X-ray photons transmitted through an object. The pixel size of the Ce:GACC scintillator array is 02 mm, and the pixels are separated by 50-mu m-wide micro grooves, The image sensor has an area of 20 x 20 mm(2) and a thickness of 1.0 mm, and it achieves an excellent spatial resolution of 0.3-0.4 mm and energy resolutions of 12% and 18% (FVVHM) for 122 and 59.5 keV gamma rays, respectively. We conducted an experiment to determine the local effective atomic number of metals using dual energy gamma ray sources. In addition, we developed a color composite image using mixed images Laken at three energies (31, 59.5, and 88 keV). (C). 2015 Elsevier B.V. All rights reserved.

DOI

Scopus

14

被引用数

(Scopus)
Demonstration of three-dimensional imaging based on handheld Compton camera

A. Kishimoto, J. Kataoka, T. Nishiyama, T. Taya, S. Kabuki

JOURNAL OF INSTRUMENTATION 10 ( 11 ) 2015年11月 [査読有り]

　概要を見る

Compton cameras are potential detectors that are capable of performing measurements across a wide energy range for medical imaging applications, such as in nuclear medicine and ion beam therapy. In previous work, we developed a handheld Compton camera to identify environmental radiation hotspots. This camera consists of a 3D position-sensitive scintillator array and multi-pixel photon counter arrays. In this work, we reconstructed the 3D image of a source via list-mode maximum likelihood expectation maximization and demonstrated the imaging performance of the handheld Compton camera. Based on both the simulation and the experiments, we confirmed that multi-angle data acquisition of the imaging region significantly improved the spatial resolution of the reconstructed image in the direction vertical to the detector. The experimental spatial resolutions in the X, Y, and Z directions at the center of the imaging region were 6.81 mm +/- 0.13 mm, 6.52 mm +/- 0.07 mm and 6.71 mm +/- 0.11 mm (FWHM), respectively. Results of multi-angle data acquisition show the potential of reconstructing 3D source images.

DOI

Scopus

20

被引用数

(Scopus)
携帯型コンプトンカメラを用いた3次元イメージングの実証

岸本彩, 片岡淳, 西山徹ほか

Journal of Instrumentation 10 ( 11 ) P11001 2015年11月 [査読有り]

DOI

Scopus

20

被引用数

(Scopus)
FIRST NuSTAR OBSERVATIONS of MRK 501 WITHIN A RADIO to TeV MULTI-INSTRUMENT CAMPAIGN

A. Furniss, K. Noda, S. Boggs, J. Chiang, F. Christensen, W. Craig, P. Giommi, C. Hailey, F. Harisson, G. Madejski, K. Nalewajko, M. Perri, D. Stern, M. Urry, F. Verrecchia, W. Zhang, M. L. Ahnen, S. Ansoldi, L. A. Antonelli, P. Antoranz, A. Babic, B. Banerjee, P. Bangale, U. Barres De Almeida, J. A. Barrio, J. Becerra González, W. Bednarek, E. Bernardini, B. Biasuzzi, A. Biland, O. Blanch, S. Bonnefoy, G. Bonnoli, F. Borracci, T. Bretz, E. Carmona, A. Carosi, A. Chatterjee, R. Clavero, P. Colin, E. Colombo, J. L. Contreras, J. Cortina, S. Covino, P. Da Vela, F. Dazzi, A. De Angelis, G. De Caneva, B. De Lotto, E. De Oña Wilhelmi, C. Delgado Mendez, F. Di Pierro, D. Dominis Prester, D. Dorner, M. Doro, S. Einecke, D. Eisenacher Glawion, D. Elsaesser, A. Fernández-Barral, D. Fidalgo, M. V. Fonseca, L. Font, K. Frantzen, C. Fruck, D. Galindo, R. J. García López, M. Garczarczyk, D. Garrido Terrats, M. Gaug, P. Giammaria, N. Godinović, A. González Muñoz, D. Guberman, Y. Hanabata, M. Hayashida, J. Herrera, J. Hose, D. Hrupec, G. Hughes, W. Idec, H. Kellermann, K. Kodani, Y. Konno, H. Kubo, J. Kushida, A. La Barbera, D. Lelas, N. Lewandowska, E. Lindfors, S. Lombardi, F. Longo, M. López, R. López-Coto, A. López-Oramas, E. Lorenz, P. Majumdar, M. Makariev, K. Mallot, G. Maneva, M. Manganaro

Astrophysical Journal 812 ( 1 ) 2015年10月

　概要を見る

We report on simultaneous broadband observations of the TeV-emitting blazar Markarian 501 between 2013 April 1 and August 10, including the first detailed characterization of the synchrotron peak with Swift and NuSTAR. During the campaign, the nearby BL Lac object was observed in both a quiescent and an elevated state. The broadband campaign includes observations with NuSTAR, MAGIC, VERITAS, the Fermi Large Area Telescope, Swift X-ray Telescope and UV Optical Telescope, various ground-based optical instruments, including the GASP-WEBT program, as well as radio observations by OVRO, Metsähovi, and the F-Gamma consortium. Some of the MAGIC observations were affected by a sand layer from the Saharan desert, and had to be corrected using event-by-event corrections derived with a Light Detection and Ranging (LIDAR) facility. This is the first time that LIDAR information is used to produce a physics result with Cherenkov Telescope data taken during adverse atmospheric conditions, and hence sets a precedent for the current and future ground-based gamma-ray instruments. The NuSTAR instrument provides unprecedented sensitivity in hard X-rays, showing the source to display a spectral energy distribution (SED) between 3 and 79 keV consistent with a log-parabolic spectrum and hard X-ray variability on hour timescales. None (of the four extended NuSTAR observations) show evidence of the onset of inverse-Compton emission at hard X-ray energies. We apply a single-zone equilibrium synchrotron self-Compton (SSC) model to five simultaneous broadband SEDs. We find that the SSC model can reproduce the observed broadband states through a decrease in the magnetic field strength coinciding with an increase in the luminosity and hardness of the relativistic leptons responsible for the high-energy emission.

DOI

Scopus

58

被引用数

(Scopus)
THE THIRD CATALOG OF ACTIVE GALACTIC NUCLEI DETECTED BY THE FERMI LARGE AREA TELESCOPE

M. Ackermann, M. Ajello, W. B. Atwood, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, J. Becerra Gonzalez, R. Bellazzini, E. Bissaldi, R. D. Blandford, E. D. Bloom, R. Bonino, E. Bottacini, T. J. Brandt, J. Bregeon, R. J. Britto, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, M. Caragiulo, P. A. Caraveo, B. Carpenter, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, G. Chiaro, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, S. Cutini, R. D'Abrusco, F. D'Ammando, A. De Angelis, R. Desiante, S. W. Digel, L. Di Venere, P. S. Drell, C. Favuzzi, S. J. Fegan, E. C. Ferrara, J. Finke, W. B. Focke, A. Franckowiak, L. Fuhrmann, Y. Fukazawa, A. K. Furniss, P. Fusco, F. Gargano, D. Gasparrini, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, J. E. Grove, S. Guiriec, J. W. Hewitt, A. B. Hill, D. Horan, R. Itoh, G. Jóhannesson, A. S. Johnson, W. N. Johnson, J. Kataoka, T. Kawano, F. Krauss, M. Kuss, G. La Mura, S. Larsson, L. Latronico, C. Leto, J. Li, L. Li, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, M. Mayer, M. N. Mazziotta, J. E. McEnery, P. F. Michelson, T. Mizuno, A. A. Moiseev, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia

Astrophysical Journal 810 ( 1 ) 2015年09月

　概要を見る

The third catalog of active galactic nuclei (AGNs) detected by the Fermi-LAT (3LAC) is presented. It is based on the third Fermi-LAT catalog (3FGL) of sources detected between 100 MeV and 300 GeV with a Test Statistic greater than 25, between 2008 August 4 and 2012 July 31. The 3LAC includes 1591 AGNs located at high Galactic latitudes (), a 71% increase over the second catalog based on 2 years of data. There are 28 duplicate associations, thus 1563 of the 2192 high-latitude gamma-ray sources of the 3FGL catalog are AGNs. Most of them (98%) are blazars. About half of the newly detected blazars are of unknown type, i.e., they lack spectroscopic information of sufficient quality to determine the strength of their emission lines. Based on their gamma-ray spectral properties, these sources are evenly split between flat-spectrum radio quasars (FSRQs) and BL Lacs. The most abundant detected BL Lacs are of the high-synchrotron-peaked (HSP) type. About 50% of the BL Lacs have no measured redshifts. A few new rare outliers (HSP-FSRQs and high-luminosity HSP BL Lacs) are reported. The general properties of the 3LAC sample confirm previous findings from earlier catalogs. The fraction of 3LAC blazars in the total population of blazars listed in BZCAT remains non-negligible even at the faint ends of the BZCAT-blazar radio, optical, and X-ray flux distributions, which hints that even the faintest known blazars could eventually shine in gamma-rays at LAT-detection levels. The energy-flux distributions of the different blazar populations are in good agreement with extrapolation from earlier catalogs.

DOI

Scopus

510

被引用数

(Scopus)
25pSJ-5 ASTRO-H搭載硬X線撮像検出器エネルギー較正手法と実機検証

三村健人, 佐藤悟朗, 小林翔悟, 村上浩章, 片岡淳, 三宅克馬, 大野雅功, 古田禄大, 室田優紀, 小野光, 加藤佑一, 笹野理, 櫻井壮希, 中野俊男, 中澤知洋, 牧島一夫, 萩野浩一, 小高裕和, 川原田円, 佐藤理江, 渡辺伸, 国分紀秀, 高橋忠幸, 湯浅孝行, 斉藤新也, 勝田準一郎, 高橋弘充, 深沢泰司, 山岡和貴, 田島宏康, 谷津陽一, 内山秀樹, HXIチーム

日本物理学会講演概要集 70 ( 2 ) 353 - 353 2015年09月

DOI CiNii
The CALorimetric Electron Telescope (CALET) for high-energy astroparticle physics on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, M. G. Bagliesi, G. Bigongiari, W. R. Binns, S. Bonechi, M. Bongi, J. H. Buckley, G. Castellini, M. L. Cherry, G. Collazuol, K. Ebisawa, V. Di Felice, H. Fuke, T. G. Guzik, T. Hams, M. Hareyama, N. Hasebe, K. Hibino, M. Ichimura, K. Ioka, M. H. Israel, A. Javaid, E. Kamioka, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, N. Kawanaka, H. Kitamura, T. Kotani, H. S. Krawczynski, J. F. Krizmanic, A. Kubota, S. Kuramata, T. Lomtadze, P. Maestro, L. Marcelli, P. S. Marrocchesi, J. W. Mitchell, S. Miyake, K. Mizutani, A. A. Moiseev, K. Mori, M. Mori, N. Mori, H. M. Motz, K. Munakata, H. Murakami, Y. E. Nakagawa, S. Nakahira, J. Nishimura, S. Okuno, J. F. Ormes, S. Ozawa, F. Palma, P. Papini, B. F. Rauch, S. B. Ricciarini, T. Sakamoto, M. Sasaki, M. Shibata, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, I. Takahashi, M. Takayanagi, M. Takita, T. Tamura, N. Tateyama, T. Terasawa, H. Tomida, S. Torii, Y. Tunesada, Y. Uchihori, S. Ueno, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, T. Yuda

Journal of Physics: Conference Series 632 ( 1 ) 2015年08月

　概要を見る

The CALorimetric Electron Telescope (CALET) is a space experiment, currently under development by Japan in collaboration with Italy and the United States, which will measure the flux of cosmic-ray electrons (and positrons) up to 20 TeV energy, of gamma rays up to 10 TeV, of nuclei with Z from 1 to 40 up to 1 PeV energy, and will detect gamma-ray bursts in the 7 keV to 20 MeV energy range during a 5 year mission. These measurements are essential to investigate possible nearby astrophysical sources of high energy electrons, study the details of galactic particle propagation and search for dark matter signatures. The main detector of CALET, the Calorimeter, consists of a module to identify the particle charge, followed by a thin imaging calorimeter (3 radiation lengths) with tungsten plates interleaving scintillating fibre planes, and a thick energy measuring calorimeter (27 radiation lengths) composed of lead tungstate logs. The Calorimeter has the depth, imaging capabilities and energy resolution necessary for excellent separation between hadrons, electrons and gamma rays. The instrument is currently being prepared for launch (expected in 2015) to the International Space Station ISS, for installation on the Japanese Experiment Module - Exposure Facility (JEM-EF).

DOI

Scopus

9

被引用数

(Scopus)
Probing the precise location of the radio core in the TeV blazar Mrk 501 with VERA at 43 GHz

Shoko Koyama, Motoki Kino, Akihiro Doi, Kotaro Niinuma, Kazuhiro Hada, Hiroshi Nagai, Mareki Honma, Kazunori Akiyama, Marcello Giroletti, Gabriele Giovannini, Monica Orienti, Naoki Isobe, Jun Kataoka, David Paneque, Hideyuki Kobayashi, Keiichi Asada

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 67 ( 4 ) 2015年08月 [査読有り]

　概要を見る

We investigate the position of the radio core in a blazar by multi-epoch astrometric observations at 43 GHz. Using the VLBI Exploration of Radio Astrometry (VERA), we have conducted four adjacent observations in 2011 February and another four in 2011 October, and succeeded in measuring the position of the radio core in the TeV blazar Mrk 501 relative to a distant compact quasar NRAO 512. During our observations, we find that (1) there is no positional change within similar to 0.2mas or similar to 2.0 pc de-projected with +/- 1 sigma s error for the weighted-mean phase-referenced positions of theMrk 501 core relative to NRAO 512 over four adjacent days, and (2) there is an indication of position change for the 3C 345 core relative to NRAO 512. By applying our results to the standard internal shock model for blazars, we constrain the bulk Lorenz factors of the ejecta.

DOI

Scopus

3

被引用数

(Scopus)
GLOBAL STRUCTURE OF ISOTHERMAL DIFFUSE X-RAY EMISSION ALONG THE FERMI BUBBLES

J. Kataoka, M. Tahara, T. Totani, Y. Sofue, Y. Inoue, S. Nakashima, C. C. Cheung

ASTROPHYSICAL JOURNAL 807 ( 1 ) 2015年07月 [査読有り]

　概要を見る

In our previous works, we found absorbed thermal X-ray plasma with kT similar or equal to 0.3 keV observed ubiquitously near the edges of the Fermi bubbles and interpreted this emission as weakly shock-heated Galactic halo gas. Here we present a systematic and uniform analysis of archival Suzaku (29 pointings; 6 newly presented) and Swift (68 pointings; 49 newly presented) data within Galactic longitudes vertical bar l vertical bar < 20 degrees and latitude 5 degrees less than or similar to vertical bar b vertical bar < 60 degrees, covering the whole extent of the Fermi bubbles. We show that the plasma temperature is constant at kT similar or equal to 0.30 +/- 0.07 keV, while the emission measure (EM) varies by an order of magnitude, increasing toward the Galactic center (i.e., low vertical bar b vertical bar) with enhancements at the North Polar Spur (NPS), SE-claw, and NW-clump features. Moreover, the EM distribution of kT similar or equal to 0.30 keV plasma is highly asymmetric in the northern and southern bubbles. Although the association of the X-ray emission with the bubbles is not conclusive, we compare the observed EM properties with simple models assuming (i) a filled halo without bubbles, whose gas density follows a hydrostatic isothermal model (King profile), and (ii) a bubble-in-halo in which two identical bubbles expand into the halo, forming thick shells of swept halo gas. We argue that the EM profile in the north (b > 0 degrees) favors (ii), whereas that of the south (b < 0 degrees) is rather close to (i), but a weak excess signature is clearly detected also in the south like NPS (South Polar Spur). Such an asymmetry, if due to the bubbles, cannot be fully understood only by the inclination of bubbles' axis against the Galactic disk normal, thus suggesting asymmetric outflow due to different environmental/initial conditions.

DOI

Scopus

36

被引用数

(Scopus)
フェルミバブルに付随した、熱的拡散X線プラズマの大局的構造

J.Kataoka

The Astrophysical Journal 807 ( 1 ) 77 - 89 2015年07月 [査読有り]

DOI

Scopus

36

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE THIRD SOURCE CATALOG

F. Acero, M. Ackermann, M. Ajello, A. Albert, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, A. Belfiore, R. Bellazzini, E. Bissaldi, R. D. Blandford, E. D. Bloom, J. R. Bogart, R. Bonino, E. Bottacini, J. Bregeon, R. J. Britto, P. Bruel, R. Buehler, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, R. Caputo, M. Caragiulo, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, E. Charles, R. C.G. Chaves, A. Chekhtman, C. C. Cheung, J. Chiang, G. Chiaro, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, S. Cutini, F. D'Ammando, A. De Angelis, M. Deklotz, F. De Palma, R. Desiante, S. W. Digel, L. Di Venere, P. S. Drell, R. Dubois, D. Dumora, C. Favuzzi, S. J. Fegan, E. C. Ferrara, J. Finke, A. Franckowiak, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, D. Hadasch, A. K. Harding, E. Hays, J. W. Hewitt, A. B. Hill, D. Horan, G. Iafrate, T. Jogler, G. Jóhannesson, R. P. Johnson, A. S. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, J. Kataoka, J. Katsuta, M. Kuss, G. La Mura, D. Landriu, S. Larsson, L. Latronico, M. Lemoine-Goumard, J. Li, L. Li, F. Longo

Astrophysical Journal, Supplement Series 218 ( 2 ) 2015年06月

　概要を見る

We present the third Fermi Large Area Telescope (LAT) source catalog (3FGL) of sources in the 100 MeV-300 GeV range. Based on the first 4 yr of science data from the Fermi Gamma-ray Space Telescope mission, it is the deepest yet in this energy range. Relative to the Second Fermi LAT catalog, the 3FGL catalog incorporates twice as much data, as well as a number of analysis improvements, including improved calibrations at the event reconstruction level, an updated model for Galactic diffuse γ-ray emission, a refined procedure for source detection, and improved methods for associating LAT sources with potential counterparts at other wavelengths. The 3FGL catalog includes 3033 sources above significance, with source location regions, spectral properties, and monthly light curves for each. Of these, 78 are flagged as potentially being due to imperfections in the model for Galactic diffuse emission. Twenty-five sources are modeled explicitly as spatially extended, and overall 238 sources are considered as identified based on angular extent or correlated variability (periodic or otherwise) observed at other wavelengths. For 1010 sources we have not found plausible counterparts at other wavelengths. More than 1100 of the identified or associated sources are active galaxies of the blazar class; several other classes of non-blazar active galaxies are also represented in the 3FGL. Pulsars represent the largest Galactic source class. From source counts of Galactic sources we estimate that the contribution of unresolved sources to the Galactic diffuse emission is ∼3% at 1 GeV.

DOI

Scopus

1363

被引用数

(Scopus)
Erratum: THe second catalog of active galactic nuclei detected by the fermi large area telescope (Astrophysical Journal (2011) 743 (171))

M. Ackermann, M. Ajello, A. Allafort, E. Antolini, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, E. Bottacini, A. Bouvier, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, L. Costamante, S. Cutini, A. De Angelis, F. De Palma, C. D. Dermer, S. W. Digel, E. Do Couto E Silva, P. S. Drell, R. Dubois, L. Escande, C. Favuzzi, S. J. Fegan, E. C. Ferrara, J. Finke, W. B. Focke, P. Fortin, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, J. E. Grove, S. Guiriec, M. Gustafsson, D. Hadasch, M. Hayashida, E. Hays, S. E. Healey, D. Horan, X. Hou, R. E. Hughes, G. Iafrate, G. Jóhannesson, A. S. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, J. Knödlseder, M. Kuss, J. Lande, S. Larsson, L. Latronico, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, M. N. Mazziotta, W. McConville

Astrophysical Journal 806 ( 1 ) 2015年06月

DOI

Scopus

2

被引用数

(Scopus)
Metal enrichment in the Fermi bubbles as a probe of their origin

Yoshiyuki Inoue, Shinya Nakashima, Masaya Tahara, Jun Kataoka, Tomonori Totani, Yutaka Fujita, Yoshiaki Sofue

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 67 ( 3 ) 2015年06月 [査読有り]

　概要を見る

The Fermi bubbles are gigantic gamma-ray structures in our Galaxy. The physical origin of the bubbles is still under debate. The leading scenarios can be divided into two categories. One is nuclear star-forming activity similar to extragalactic starburst galaxies and the other is past active galactic nucleus (AGN)-like activity of the Galactic center supermassive black hole. In this letter, we propose that metal abundance measurements will provide an important clue to probe their origin. Based on a simple spherically symmetric bubble model, we find that the generated metallicity and abundance patterns of the bubbles' gas strongly depend on assumed star formation or AGN activities. Star formation scenarios predict higher metallicities and abundance ratios of [O/Fe] and [Ne/Fe] than AGN scenarios do because of supernovae ejecta. Furthermore, the resultant abundance depends on the gamma-ray emission process because different mass injection histories are required for the different gamma-ray emission processes due to the acceleration and cooling time scales of non-thermal particles. Future X-ray missions such as ASTRO-H and Athena will give a clue to probe the origin of the bubbles through abundance measurements with their high energy resolution instruments.

DOI

Scopus

9

被引用数

(Scopus)
Recent progress of MPPC-based scintillation detectors in high precision X-ray and gamma-ray imaging

J. Kataoka, A. Kishimoto, T. Fujita, T. Nishiyama, Y. Kurei, T. Tsujikawa, T. Oshima, T. Taya, Y. Iwamoto, H. Ogata, H. Okochi, S. Ohsuka, H. Ikeda, S. Yamamoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 784 248 - 254 2015年06月 [査読有り]

　概要を見る

The multi-pixel photon counter (MPPC) is a promising light sensor for various applications, not only in physics experiments but also in nuclear medicine, industry, and even high-energy astrophysics. In this paper, we present the current status and most recent progress of the MPPC-based scintillation detectors, such as (1) a high-precision X-ray and gamma-ray spectral image sensor, (2) next-generation PET detectors with MRI, TOF, and DOI measurement capabilities, and (3) a compact gamma camera for environmental radiation surveys. We first present a new method of fabricating a Ce:GAGG scintillator plate (1 or 2 mm thick) with ultra-fine resolution (0.2 mm/pixel), cut using a dicing saw to create 50 mu m wide micro-grooves. When the plate is optically coupled with a large-area MPPC array, excellent spatial resolution of 0.48 mm (FWHM) and energy resolution of 14% (FWHM) are obtained for 122 keV gamma rays. Hence, the detector can act as a convenient "multi-color" imaging device that can potentially be used for future SPECT and photon-counting CT. We then show a prototype system for a high-resolution MPPC-based PET scanner that can realize similar or equal to 1 mm (FWHM) spatial resolution, even under a strong magnetic field of 4.7 T. We develop a front-end ASIC intended for future TOF-PET scanner with a 16-channel readout that achieves a coincidence time resolution of 489 ps (FWHM). A novel design for a module with DOI-measurement capability for gamma rays is also presented by measuring the pulse height ratio of double-sided MPPCs coupled at both ends of scintillation crystal block. Finally, we present the concept of a two-plane Compton camera consisting of Ce:GAGG scintillator arrays coupled with thin MPPC arrays. As a result of the thin and compact features of the MPPC device, the camera not only achieves a small size (14 x 14 x 15 cm(3)) and light weight (1.9 kg) but also excellent sensitivity, compared to the conventional PMT-based pinhole camera used in Fukushima. Finally, we briefly describe a new product recently developed in conjunction with Hamamatsu Photonics K.K. that offers improved sensitivity and angular resolution of Delta theta similar to 8 degrees (FWHM) at 662 key, by incorporating DOI-segmented scintillator arrays. (C) 2014 Elsevier B.V. All rights reserved.

DOI

Scopus

53

被引用数

(Scopus)
MPPCを基盤としたシンチレーション検出器を用いたX線・ガンマ線イメージングの最新動向

J.Kataoka

Nuclear Instruments and Method, Section-A 784 248 - 254 2015年06月 [査読有り]

DOI

Scopus

53

被引用数

(Scopus)
The CALorimetric Electron Telescope (CALET) for high-energy astroparticle physics on the International Space Station

O. Adriani, Y. Akaike, K. Asano, Y. Asaoka, M. G. Bagliesi, G. Bigongiari, W. R. Binns, S. Bonechi, M. Bongi, J. H. Buckley, G. Castellini, M. L. Cherry, G. Collazuol, K. Ebisawa, V. Di Felice, H. Fuke, T. G. Guzik, T. Hams, M. Hareyama, N. Hasebe, K. Hibino, M. Ichimura, K. Ioka, M. H. Israel, A. Javaid, E. Kamioka, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, N. Kawanaka, H. Kitamura, T. Kotani, H. S. Krawczynski, J. F. Krizmanic, A. Kubota, S. Kuramata, T. Lomtadze, P. Maestro, L. Marcelli, P. S. Marrocchesi, J. W. Mitchell, S. Miyake, K. Mizutani, A. A. Moiseev, K. Mori, M. Mori, N. Mori, H. M. Motz, K. Munakata, H. Murakami, Y. E. Nakagawa, S. Nakahira, J. Nishimura, S. Okuno, J. F. Ormes, S. Ozawa, F. Palma, P. Papini, B. F. Rauch, S. B. Ricciarini, T. Sakamoto, M. Sasaki, M. Shibata, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, I. Takahashi, M. Takayanagi, M. Takita, T. Tamura, N. Tateyama, T. Terasawa, H. Tomida, S. Torii, Y. Tunesada, Y. Uchihori, S. Ueno, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, T. Yuda

EPJ Web of Conferences 95 2015年05月

　概要を見る

The CALorimetric Electron Telescope (CALET) is a space experiment, currently under development by Japan in collaboration with Italy and the United States, which will measure the flux of cosmic-ray electrons (and positrons) up to 20 TeV energy, of gamma rays up to 10 TeV, of nuclei with Z from 1 to 40 up to 1 PeV energy, and will detect gamma-ray bursts in the 7 keV to 20 MeV energy range during a 5 year mission. These measurements are essential to investigate possible nearby astrophysical sources of high energy electrons, study the details of galactic particle propagation and search for dark matter signatures. The main detector of CALET, the Calorimeter, consists of a module to identify the particle charge, followed by a thin imaging calorimeter (3 radiation lengths) with tungsten plates interleaving scintillating fibre planes, and a thick energy measuring calorimeter (27 radiation lengths) composed of lead tungstate logs. The Calorimeter has the depth, imaging capabilities and energy resolution necessary for excellent separation between hadrons, electrons and gamma rays. The instrument is currently being prepared for launch (expected in 2015) to the International Space Station ISS, for installation on the Japanese Experiment Module - Exposure Facility (JEM-EF).

DOI

Scopus

1

被引用数

(Scopus)
MULTI-WAVELENGTH OBSERVATIONS OF THE BLACK WIDOW PULSAR 2FGL J2339.6-0532 WITH OISTER AND SUZAKU

Yoichi Yatsu, Jun Kataoka, Yosuke Takahashi, Yutaro Tachibana, Nobuyuki Kawai, Shimpei Shibata, Sean Pike, Taketoshi Yoshii, Makoto Arimoto, Yoshihiko Saito, Takeshi Nakamori, Kazuhiro Sekiguchi, Daisuke Kuroda, Kenshi Yanagisawa, Hidekazu Hanayama, Makoto Watanabe, Ko Hamamoto, Hikaru Nakao, Akihito Ozaki, Kentaro Motohara, Masahiro Konishi, Ken Tateuchi, Noriyuki Matsunaga, Tomoki Morokuma, Takahiro Nagayama, Katsuhiro Murata, Hiroshi Akitaya, Michitoshi Yoshida, Gamal B. Ali, A. Essam Mohamed, Mizuki Isogai, Akira Arai, Hidenori Takahashi, Osamu Hashimoto, Ryo Miyanoshita, Toshihiro Omodaka, Jun Takahashi, Noritaka Tokimasa, Kentaro Matsuda, Shin-Ichiro Okumura, Kota Nishiyama, Seitaro Urakawa, Daisaku Nogami, Yumiko Oasa

ASTROPHYSICAL JOURNAL 802 ( 2 ) 2015年04月

　概要を見る

Multi-wavelength observations of the black widow binary system 2FGL J2339.6-0532 are reported. The Fermi gamma-ray source 2FGL J2339.6-0532 was recently categorized as a black widow in which a recycled millisecond pulsar (MSP) is evaporating the companion star with its powerful pulsar wind. Our optical observations show clear sinusoidal light curves due to the asymmetric temperature distribution of the companion star. Assuming a simple geometry, we constrained the range of the inclination angle of the binary system to 52 degrees < i < 59 degrees, which enables us to discuss the interaction between the pulsar wind and the companion in detail. The X-ray spectrum consists of two components: a soft, steady component that seems to originate from the surface of the MSP, and a hard, variable component from the wind-termination shock near the companion star. The measured X-ray luminosity is comparable to the bolometric luminosity of the companion, meaning that the heating efficiency is less than 0.5. In the companion orbit, 10(11) cm from the pulsar, the pulsar wind is already in the particle-dominant stage with a magnetization parameter of sigma < 0.1. In addition, we precisely investigated the time variations of the X-ray periodograms and detected a weakening of the orbital modulation. The observed phenomenon may be related to unstable pulsar wind activity or weak mass accretion, both of which can result in the temporal extinction of the radio pulse.

DOI

Scopus

9

被引用数

(Scopus)
MULTI-WAVELENGTH OBSERVATIONS OF THE BLACK WIDOW PULSAR 2FGL J2339.6-0532 WITH OISTER AND SUZAKU

Yoichi Yatsu, Jun Kataoka, Yosuke Takahashi, Yutaro Tachibana, Nobuyuki Kawai, Shimpei Shibata, Sean Pike, Taketoshi Yoshii, Makoto Arimoto, Yoshihiko Saito, Takeshi Nakamori, Kazuhiro Sekiguchi, Daisuke Kuroda, Kenshi Yanagisawa, Hidekazu Hanayama, Makoto Watanabe, Ko Hamamoto, Hikaru Nakao, Akihito Ozaki, Kentaro Motohara, Masahiro Konishi, Ken Tateuchi, Noriyuki Matsunaga, Tomoki Morokuma, Takahiro Nagayama, Katsuhiro Murata, Hiroshi Akitaya, Michitoshi Yoshida, Gamal B. Ali, A. Essam Mohamed, Mizuki Isogai, Akira Arai, Hidenori Takahashi, Osamu Hashimoto, Ryo Miyanoshita, Toshihiro Omodaka, Jun Takahashi, Noritaka Tokimasa, Kentaro Matsuda, Shin-Ichiro Okumura, Kota Nishiyama, Seitaro Urakawa, Daisaku Nogami, Yumiko Oasa

ASTROPHYSICAL JOURNAL 802 ( 2 ) 84 2015年04月 [査読有り]

　概要を見る

Multi-wavelength observations of the black widow binary system 2FGL J2339.6-0532 are reported. The Fermi gamma-ray source 2FGL J2339.6-0532 was recently categorized as a black widow in which a recycled millisecond pulsar (MSP) is evaporating the companion star with its powerful pulsar wind. Our optical observations show clear sinusoidal light curves due to the asymmetric temperature distribution of the companion star. Assuming a simple geometry, we constrained the range of the inclination angle of the binary system to 52 degrees < i < 59 degrees, which enables us to discuss the interaction between the pulsar wind and the companion in detail. The X-ray spectrum consists of two components: a soft, steady component that seems to originate from the surface of the MSP, and a hard, variable component from the wind-termination shock near the companion star. The measured X-ray luminosity is comparable to the bolometric luminosity of the companion, meaning that the heating efficiency is less than 0.5. In the companion orbit, 10(11) cm from the pulsar, the pulsar wind is already in the particle-dominant stage with a magnetization parameter of sigma < 0.1. In addition, we precisely investigated the time variations of the X-ray periodograms and detected a weakening of the orbital modulation. The observed phenomenon may be related to unstable pulsar wind activity or weak mass accretion, both of which can result in the temporal extinction of the radio pulse.

DOI

Scopus

9

被引用数

(Scopus)
すざく衛星によるフェルミバブルの観測：MAXI-SSCで発見された北端キャップと南東爪構造

田原将也, 片岡淳, 竹内勇人ほか

The Astrophysical Journal 802 ( 2 ) 91 2015年04月 [査読有り]

DOI

Scopus

21

被引用数

(Scopus)
Multi-wavelength Observations of the Black Widow Pulsar 2FGL J2339.6-0532 with OISTER and Suzaku

Yatsu, Y, Kataoka, J, Takahashi, Y, Tachibana, Y, Kawai, N, Shibata, S, Pike, S, Yoshii, T, Arimoto, M, Saito, Y, Nakamori, T, Sekiguchi, K, Kuroda, D, Yanagisawa, K, Hanayama, H, Watanabe, M, Hamamoto, K, Nakao, H, Ozaki, A, Motohara, K, Konishi, M, Tateuchi, K, Matsunaga, N, Morokuma, T, Nagayama, T, Murata, K, Akitaya, H, Yoshida, M, Ali, G. B, Essam Mohamed, A, Isogai, M, Arai, A, Takahashi, H, Hashimoto, O, Miyanoshita, R, Omodaka, T, Takahashi, J, Tokimasa, N, Matsuda, K, Okumura, S.-i, Nishiyama, K, Urakawa, S, Nogami, D, Oasa, Y, OISTER Team

The Astrophysical Journal 802 84 2015年03月 [査読有り]

DOI
Six Years of Fermi-LAT and Multi-Wavelength Monitoring of the Broad-Line Radio Galaxy 3c 120: Jet Dissipation At Sub-Parsec Scales from the Central Engine

Tanaka Y.~T, Doi A, Inoue Y, Cheung C.~C, Stawarz L, Fukazawa Y, Gurwell M.~A, Tahara M, Kataoka J, Itoh R

The Astrophysical Journal Letters 799 ( 2 ) L18 - 6 2015年02月 [査読有り]

DOI

Scopus

17

被引用数

(Scopus)
The spectrum of isotropic diffuse gamma-ray emission between 100 MeV and 820 GeV

M. Ackermann, M. Ajello, A. Albert, W. B. Atwood, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, E. Bissaldi, R. D. Blandford, E. D. Bloom, E. Bottacini, T. J. Brandt, J. Bregeon, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, M. Caragiulo, P. A. Caraveo, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, J. Chiang, G. Chiaro, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, A. Cuoco, S. Cutini, F. D'Ammando, A. De Angelis, F. De Palma, C. D. Dermer, S. W. Digel, E. Do Couto E Silva, P. S. Drell, C. Favuzzi, E. C. Ferrara, W. B. Focke, A. Franckowiak, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, S. Germani, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, G. Godfrey, G. A. Gomez-Vargas, I. A. Grenier, S. Guiriec, M. Gustafsson, D. Hadasch, K. Hayashi, E. Hays, J. W. Hewitt, P. Ippoliti, T. Jogler, G. Jóhannesson, A. S. Johnson, W. N. Johnson, T. Kamae, J. Kataoka, J. Knödlseder, M. Kuss, S. Larsson, L. Latronico, J. Li, L. Li, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Manfreda, F. Massaro, M. Mayer, M. N. Mazziotta, J. E. McEnery, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, R. Nemmen, E. Nuss, T. Ohsugi

Astrophysical Journal 799 ( 1 ) 2015年01月

　概要を見る

The γ-ray sky can be decomposed into individually detected sources, diffuse emission attributed to the interactions of Galactic cosmic rays with gas and radiation fields, and a residual all-sky emission component commonly called the isotropic diffuse γ-ray background (IGRB). The IGRB comprises all extragalactic emissions too faint or too diffuse to be resolved in a given survey, as well as any residual Galactic foregrounds that are approximately isotropic. The first IGRB measurement with the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope (Fermi ) used 10 months of sky-survey data and considered an energy range between 200 MeV and 100 GeV. Improvements in event selection and characterization of cosmic-ray backgrounds, better understanding of the diffuse Galactic emission (DGE), and a longer data accumulation of 50 months allow for a refinement and extension of the IGRB measurement with the LAT, now covering the energy range from 100 MeV to 820 GeV. The IGRB spectrum shows a significant high-energy cutoff feature and can be well described over nearly four decades in energy by a power law with exponential cutoff having a spectral index of 2.32 ± 0.02 and a break energy of (279 ± 52) GeV using our baseline DGE model. The total intensity attributed to the IGRB is (7.2 ± 0.6) x 10-6 cm-2 s-1 sr-1 above 100 MeV, with an additional +15%/-30% systematic uncertainty due to the Galactic diffuse foregrounds.

DOI

Scopus

634

被引用数

(Scopus)
27pSJ-1 CTA報告96 : 全体報告

手嶋政廣, 窪秀利, 戸谷友則, 浅野勝晃, 井岡邦仁, 池野祐平, 石尾一馬, 稲田知大, 井上進, 井上剛志, 井上芳幸, 猪目祐介, 岩村由樹, 内山泰伸, 梅津陽平, 大石理子, 大岡秀行, 大平豊, 奥村曉, 小野祥弥, 折戸玲子, 加賀谷美佳, 格和純, 片岡淳, 片桐秀明, 加藤翔, 掃部寛隆, 河島孝則, 川中宣太, 木坂将大, 岸田柊, 櫛田淳子, 郡司修一, 郡和範, 小山志勇, 今野裕介, 齋藤隆之, 榊直人, 佐藤雄太, 佐野栄俊, 澤田真理, 重中茜, 柴田徹, 高橋慶太郎, 高橋弘充, 高橋光成, 高見将太, 武田淳希, 田島宏康, 立原研悟, 田中周太, 田中孝明, 田中真伸, 田中康之, 谷川俊介, 千川道幸, 長紀仁, 辻本晋平, 鶴剛, 寺田幸功, 當真賢二, 門叶冬樹, 友野弥生, 鳥居和史, 内藤統也, 中嶋大輔, 長瀧重博, 中森健之, 中山和則, 永吉勤, 西嶋恭司, 野田浩司, 畑中謙一郎, 早川貴敬, 林田将明, 原敏, 馬場彩, 日高直哉, 平井亘, 広谷幸一, 深沢泰司, 深見哲志, 福井康雄, 福田達哉, 藤田裕, 増田周, 松岡俊介, 松本浩典, 水野恒史, 村石浩, 村瀬孔大, 本橋大輔, 森浩二, 柳田昭平, 山崎了, 山根暢仁, 山本常夏, 山本宏昭, 吉池智史, 吉越貴紀, 吉田篤正, 吉田龍生, 吉田麻佑, 李兆衡, Tan Dang Viet, Hadasch Daniela, Mazin Daniel, CTA Japan Collaboration

日本物理学会講演概要集 70 390 - 390 2015年

DOI CiNii
25pSJ-3 ASTRO-H衛星搭載軟ガンマ線検出器の衛星総合試験における試験結果

林克洋, 田島宏康, 深沢泰司, 渡辺伸, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 国分紀秀, 佐藤悟朗, 佐藤理江, 高橋忠幸, 武田伸一郎, 田代信, 田中孝明, 寺田幸功, 中澤知洋, 中森健之, 原山淳, Blandford Roger, 牧島一夫, Madejski Grzegorz, 水野恒史, 森國城, 谷津陽一, 山岡和貴, 山田真也, 湯浅孝行, 米徳大輔, Laurent Philippe, Limousin Olivier, Lebrun Francois, SGDチーム

日本物理学会講演概要集 70 351 - 351 2015年

DOI CiNii
24aDJ-3 硬X線偏光検出器PoGOLite気球実験 : 2016年の再フライトへ向けて

高橋弘充, 河野貴文, 水野恒史, 深沢泰司, 釜江常好, 片岡淳, 田島宏康, 高橋忠幸, 河合誠之, Pearce M., Chauvin M., Kiss M., Kole M., Mikhalev V., Moretti E., PoGOLiteチーム

日本物理学会講演概要集 70 495 - 495 2015年

DOI CiNii
23pDK-3 ASTRO-H衛星搭載軟ガンマ線検出器の衛星搭載器試験結果

田島宏康, 深沢泰司, 渡辺伸, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 川原田円, 国分紀秀, 佐藤悟朗, 佐藤理江, 高橋忠幸, 高橋弘充, 武田伸一郎, 田代信, 田中孝明, 田中康之, 寺田幸功, 中澤知洋, 中森健之, 林克洋, Blandford Roger, 牧島一夫, Madejski Grzegorz, 水野恒史, 森國城, 谷津陽一, 山岡和貴, 山田真也, 米徳大輔, Laurent Philippe, Limousin Olivier, Lebrun Francois, SGDチーム

日本物理学会講演概要集 70 470 - 470 2015年

DOI CiNii
21pDD-12 フェルミ衛星によるBroad Line Radio Galaxy 3C 120のモニター観測と多波長データによるMeV/GeVガンマ線放射位置と放射機構の探査

田中康之, 土居明広, 井上芳幸, Cheung C. C., Stawarz L., 深沢泰司, Gurwell M. A., 田原将也, 片岡淳, 伊藤亮介

日本物理学会講演概要集 70 416 - 416 2015年

DOI CiNii
23pCF-13 次世代CTを目指した高精細カラー放射線イメージセンサの開発(I)

大島翼, 片岡淳, 岸本彩, 藤田卓也, 呉井洋太, 西山徹, 山本誠一, 尾川浩一

日本物理学会講演概要集 70 364 - 364 2015年

DOI CiNii
Development and evaluation of an ultra-fast ASIC for future PET scanners using TOF-capable MPPC array detectors

T. Ambe, H. Ikeda, J. Kataoka, H. Matsuda, T. Kato

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 771 66 - 73 2015年01月 [査読有り]

　概要を見る

We developed a front-end AMC for future PET scanners with Time-Of-Flight (TOF) capability to be coupled with 4 x 4 Multi-Pixel Photon Counter (MPPC) arrays. The ASIC is designed based on the open-IP project proposed by JAXA and realized in TSNIC 0.35 mu m CMOS technology. The circuit comprises 16-channel, low impedance current conveyors for effectively acquiring fast MPPC signals. For precise measurement of the coincidence timing of 511-keV gamma rays, the leading-edge method was used to discriminate the signals. We First tested the time response of the FOC by illuminating each channel of a MPPC array device 3 x 3 mm(2) in size with a Pico-second Light Pulsar with a light emission peak of 655 nm and pulse duration of 54 ps (FWHM). We obtained 105 ps (FWHM) on average for each channel in time jitter measurements. Moreover, we compensated for the time lag of each channel with inner delay circuits and succeeded in suppressing about a 700-ps lag to only 15 ps. This paper reports TOE measurements using back-to-back 511-key signals, and suggests that the ASIC can be a promising device for future TOF-PET scanners based on the MPPC array. (C) 2014 Published by Elsevier B.V.

DOI

Scopus

3

被引用数

(Scopus)
TSV-MPPCとダイシングシンチレータを用いた高精度多色ガンマ線イメージャの開発

大島翼, 片岡淳, 岸本彩ほか

Nuclear instruments & methods in physics research. Section A 803 8 - 14 2015年 [査読有り]

DOI

Scopus

14

被引用数

(Scopus)
Status and performance of the CALorimetric Electron Telescope (CALET) on the international space station

O. Adriani, Y. Akaike, Y. Asaoka, K. Asano, M. G. Bagliesi, G. Bigongiari, W. R. Binns, M. Bongi, J. H. Buckley, A. Cassese, G. Castellini, M. L. Cherry, G. Collazuol, K. Ebisawa, V. di Felice, H. Fuke, T. G. Guzik, T. Hamsa, N. Hasebe, M. Hareyama, K. Hibino, M. Ichimura, K. Ioka, M. H. Israel, A. Javaid, E. Kamioka, K. Kasahara, Y. Katayose, J. Kataoka, R. Kataoka, N. Kawanaka, H. Kitamura, T. Kotani, H. S. Krawczynski, J. F. Krizmanic, A. Kubota, S. Kuramata, T. Lomtadze, P. Maestro, L. Marcelli, P. S. Marrocchesi, J. W. Mitchell, S. Miyake, K. Mizutani, H. M. Motz, A. A. Moiseev, K. Mori, M. Mori, N. Mori, K. Munakata, H. Murakami, Y. E. Nakagawa, S. Nakahira, J. Nishimura, S. Okuno, J. F. Ormes, S. Ozawa, F. Palma, P. Papini, B. F. Rauch, S. Ricciarini, T. Sakamoto, M. Sasaki, M. Shibata, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, I. Takahashi, M. Takayanagi, M. Takita, T. Tamura, N. Tateyama, T. Terasawa, H. Tomida, S. Torii, Y. Tunesada, Y. Uchihori, S. Ueno, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, T. Yuda

Nuclear Physics B - Proceedings Supplements 256-257 225 - 232 2014年12月

　概要を見る

The CALorimetric Electron Telescope (CALET) space experiment, currently under development by Japan in collaboration with Italy and the United States, will measure the flux of cosmic-ray electrons (including positrons) to 20 TeV, gamma rays to 10 TeV and nuclei with Z=1 to 40 up to 1,000 TeV during a two-year mission on the International Space Station (ISS), extendable to five years. These measurements are essential to search for dark matter signatures, investigate the mechanism of cosmic-ray acceleration and propagation in the Galaxy and discover possible astrophysical sources of high-energy electrons nearby the Earth. The instrument consists of two layers of segmented plastic scintillators for the cosmic-ray charge identification (CHD), a 3 radiation length thick tungsten-scintillating fiber imaging calorimeter (IMC) and a 27 radiation length thick lead-tungstate calorimeter (TASC). CALET has sufficient depth, imaging capabilities and excellent energy resolution to allow for a clear separation between hadrons and electrons and between charged particles and gamma rays. The instrument will be launched to the ISS within 2014 Japanese Fiscal Year (by the end of March 2015) and installed on the Japanese Experiment Module-Exposed Facility (JEM-EF). In this paper, we will review the status and main science goals of the mission and describe the instrument configuration and performance.

DOI

Scopus

10

被引用数

(Scopus)
Development of prototype PET scanner using dual-sided readout DOI-PET modules

T. Fujita, J. Kataoka, A. Kishimoto, Y. Kurei, T. Nishiyama, T. Ohshima, T. Taya

JOURNAL OF INSTRUMENTATION 9 ( 12 ) P12015 2014年12月 [査読有り]

　概要を見る

In our previous work, we proposed a novel design for a gamma-ray detector module capable of measuring the depth of interaction (DOI). In this paper, we further developed DOI-PET detector modules and a data acquisition system, and evaluated its performance. Each detector module was composed of a 3-D scintillator array and two large-area monolithic Multi-Pixel Photon Counter (MPPC) arrays coupled to both ends of the 3-D scintillator array, leading to only 8-ch signal outputs from a module. The 3-D scintillator array was composed of 9 x 9 x 7 matrices of 1.0 x 1.0 x 3.0 mm(3) Ce:GAGG crystals. The detector module showed good energy resolution of 10.6% as measured at 511 keV and a high average peak to valley ratio higher than 8 for each pixel crystal identified in the X-Y-Z directions. Moreover, we evaluated the spatial resolution of a virtual 18-ch PET gantry simulated by using two detector modules that were flexibly controlled using both the X-stage and theta-stage in 20-degree steps. By measuring a Na-22 point source (0.25 mm in diameter), we showed that spatial resolution substantially degrades from 1.0 mm to 7.8 mm (FWHM; as measured at 0 mm and 28 mm off-center) with a non-DOI configuration, whereas the corresponding values for the DOI configuration were 0.9 mm and 1.5 mm, respectively (FWHM; as measured at 0 mm and 28 mm off-center). This preliminary study confirms that our DOI-PET module is useful for future high spatial resolution and compact small-animal PET scanners without radial image distortions at the peripheral regions of the field of view (FOV).

DOI

Scopus

4

被引用数

(Scopus)
A novel Compton camera design featuring a rear-panel shield for substantial noise reduction in gamma-ray images

T. Nishiyama, J. Kataoka, A. Kishimoto, T. Fujita, Y. Iwamoto, T. Taya, S. Ohsuka, S. Nakamura, M. Hirayanagi, N. Sakurai, S. Adachi, T. Uchiyama

JOURNAL OF INSTRUMENTATION 9 ( 12 ) C12031 2014年12月 [査読有り]

　概要を見る

After the Japanese nuclear disaster in 2011, large amounts of radioactive isotopes were released and still remain a serious problem in Japan. Consequently, various gamma cameras are being developed to help identify radiation hotspots and ensure effective decontamination operation. The Compton camera utilizes the kinematics of Compton scattering to contract images without using a mechanical collimator, and features a wide field of view. For instance, we have developed a novel Compton camera that features a small size (13x14x15 cm(3)) and light weight (1.9 kg), but which also achieves high sensitivity thanks to Ce:GAGG scintillators optically coupled wiith MPPC arrays. By definition, in such a Compton camera, gamma rays are expected to scatter in the "scatterer" and then be fully absorbed in the "absorber" (in what is called a forward-scattered event). However, high energy gamma rays often interact with the detector in the opposite direction-initially scattered in the absorber and then absorbed in the scatterer-in what is called a "back-scattered" event. Any contamination of such back-scattered events is known to substantially degrade the quality of gamma-ray images, but determining the order of gamma-ray interaction based solely on energy deposits in the scatterer and absorber is quite difficult. For this reason, we propose a novel yet simple Compton camera design that includes a rear-panel shield (a few mm thick) consisting of W or Pb located just behind the scatterer. Since the energy of scattered gamma rays in back-scattered events is much lower than that in forward-scattered events, we can effectively discriminate and reduce back-scattered events to improve the signal-to-noise ratio in the images. This paper presents our detailed optimization of the rear-panel shield using Geant4 simulation, and describes a demonstration test using our Compton camera.

DOI

Scopus

3

被引用数

(Scopus)
Development of a MPPC-based prototype gantry for future MRI-PET scanners

Y. Kurei, J. Kataoka, T. Kato, T. Fujita, T. Ohshima, T. Taya, S. Yamamoto

JOURNAL OF INSTRUMENTATION 9 ( 12 ) C12052 2014年12月 [査読有り]

　概要を見る

We have developed a high spatial resolution, compact Positron Emission Tomography (PET) module designed for small animals and intended for use in magnetic resonance imaging (MRI) systems. This module consists of large-area, 4x4 ch MPPC arrays (S11830-3344MF; Hamamatsu Photonics K. K.) optically coupled with Ce-doped (Lu, Y)(2)(SiO4)O (Ce: LYSO) scintillators fabricated into 16 x 16 matrices of 0.5 x 0.5 mm(2) pixels. We set the temperature sensor (LM73CIMK-0; National Semiconductor Corp.) at the rear of the MPPC acceptance surface, and apply optimum voltage to maintain the gain. The eight MPPC-based PET modules and coincidence circuits were assembled into a gantry arranged in a ring 90 mmin diameter to form the MPPC-based PET system. We have developed two types PET gantry: one made of non-magnetic metal and the other made of acrylonitrile butadiene styrene (ABS) resins. The PET gantry was positioned around the RF coil of the 4.7 T MRI system. We took an image of a point Na-22 source under fast spin echo (FSE) and gradient echo (GE), in order to measure the interference between the MPPC-based PET and MRI. The spatial resolution of PET imaging in a transaxial plane of about 1 mm (FWHM) was achieved in all cases. Operating with PET made of ABS has no effect on MR images, while operating with PET made of non-magnetic metal has a significant detrimental effect on MR images. This paper describes our quantitative evaluations of PET images and MR images, and presents a more advanced version of the gantry for future MRI/DOI-PET systems.

DOI

Scopus

1

被引用数

(Scopus)
Performance and field tests of a handheld Compton camera using 3-D position-sensitive scintillators coupled to multi-pixel photon counter arrays

A. Kishimoto, J. Kataoka, T. Nishiyama, T. Fujita, K. Takeuchi, H. Okochi, H. Ogata, H. Kuroshima, S. Ohsuka, S. Nakamura, M. Hirayanagi, S. Adachi, T. Uchiyama, H. Suzuki

JOURNAL OF INSTRUMENTATION 9 ( 11 ) 2014年11月 [査読有り]

　概要を見る

After the nuclear disaster in Fukushima, radiation decontamination has become particularly urgent. To help identify radiation hotspots and ensure effective decontamination operation, we have developed a novel Compton camera based on Ce-doped Gd3Al2Ga3O12 scintillators and multi-pixel photon counter (MPPC) arrays. Even though its sensitivity is several times better than that of other cameras being tested in Fukushima, we introduce a depth-of-interaction (DOI) method to further improve the angular resolution. For gamma rays, the DOI information, in addition to 2-D position, is obtained by measuring the pulse-height ratio of the MPPC arrays coupled to ends of the scintillator. We present the detailed performance and results of various field tests conducted in Fukushima with the prototype 2-D and DOI Compton cameras. Moreover, we demonstrate stereo measurement of gamma rays that enables measurement of not only direction but also approximate distance to radioactive hotspots.

DOI

Scopus

51

被引用数

(Scopus)
Qualification test of a MPPC-based PET module for future MRI-PET scanners

Y. Kurei, J. Kataoka, T. Kato, T. Fujita, H. Funamoto, T. Tsujikawa, S. Yamamoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 765 275 - 279 2014年11月 [査読有り]

　概要を見る

We have developed a high-resolution, compact Positron Emission Tomography (PET) module for future use in MRI-PET scanners. The module consists of large-area, 4 x 4 ch MPPC arrays (Hamamatsu S11827-3344MG) optically coupled with Ce:LYSO scintillators fabricated into 12 x 12 matrices of 1 x 1 mm(2) pixels. At this stage, a pair of module and coincidence circuits was assembled into an experimental prototype gantry arranged in a ring of 90 mm in diameter to form the MPPC-based PET system. The PET detector ring was then positioned around the RF coil of the 4.7 T MRI system. We took an image of a point Na-22 source under fast spin echo (FSE) and gradient echo (GE), in order to measure interference between the MPPC-based PET and the MRI We only found a slight degradation in the spatial resolution of the PET image from 1.63 to 1.70 mm (FWHM; x-direction), or 1.48-1.55 mm (FWHM; y-direction) when operating with the MRI, while the signal-to-noise ratio (SNR) of the MRI image was only degraded by 5%. These results encouraged us to develop a more advanced version of the MRI-PET gantry with eight MPPC-based PET modules, whose detailed design and first qualification Lest are also presented in this paper. (C) 2014 Elsevier B.V. All rights reserved.

DOI

Scopus

2

被引用数

(Scopus)
Two-dimensional diced scintillator array for innovative, fine-resolution gamma camera

T. Fujita, J. Kataoka, T. Nishiyama, S. Ohsuka, S. Nakamura, S. Yamamoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 765 262 - 268 2014年11月 [査読有り]

　概要を見る

We are developing a technique to fabricate fine spatial resolution (FWHM < 0.5 mm) and cost-effective photon counting detectors, by using silicon photomultipliers (SiPMs) coupled with a finely pixelated scintillator plate. Unlike traditional X-ray imagers that use a micro-columnar CskTI) plate, we can pixelate various scintillation crystal plates more than 1 mm thick, and easily develop large-area, finepitch scintillator arrays with high precision. Coupling a fine pitch scintillator array with a SiPM array results in a compact, fast-response detector that is ideal for X-ray, gamma-ray, and charged particle detection as used in autoradiography, gamma cameras, and photon counting CTs. As the first step, we fabricated a 2-D, cerium-doped Gd3Al2Ga3O12 (Ce:GAGG) scintillator array of 0.25 mm pitch, by using a dicing saw to cut micro-grooves 50 um wide into a 1.0 mm thick Ce:GAGG plate. The scinfillator plate is optically coupled with a 3.0 x 3.0 mm pixel 4 x 4 SiPM array and read-out via the resistive chargedivision network. Even when using this simple system as a gamma camera, we obtained excellent spatial resolution of 0.48 mm (F\NHM) for 122 keV gamma-rays. We will present our plans to further improve the signal-to-noise ratio in the image, and also discuss a variety of possible applications in the near future. (C) 2014 Elsevier By, All rights reserved,

DOI

Scopus

22

被引用数

(Scopus)
“Stereo Compton cameras” for the 3-D localization of radioisotopes

K.Takeuchi, J.Kataoka, T.Nishiyama

Nuclear Instruments and Methods in Physics Research Section A 765 ( 21 ) 187 - 191 2014年11月 [査読有り]

DOI

Scopus

23

被引用数

(Scopus)
Performance of the latest MPPCs with reduced dark counts and improved photon detection efficiency

T. Tsujikawa, H. Funamoto, J. Kataoka, T. Fujita, T. Nishiyama, Y. Kurei, K. Sato, K. Yamamura, S. Nakamura

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 765 ( 21 ) 247 - 251 2014年11月 [査読有り]

　概要を見る

We have tested the performance of two types of the latest Multi-Pixel Photon Counters (MPPCs; measuring 3 x 3 mm2 in size) developed by Hamamatsu Photonics K.K. The new S12572-050C is a successor to the S10362-33-050C (i.e., conventional 3 x 3-mm2 pixel MPPC of 50 pm pitch), comprises 3600 Geiger mode avalanche photodiodes (APDs), and also features high gain (up to 125 x 10(6)), a low dark count (up to 10(6) cps), and improved photon detection efficiency (PDE) by up to 30%. The S12572015C is a new type of fine-pitch (15 pM) MPPC featuring a wide dynamic range and fast timing response. This paper first presents the detailed performance of these latest MPPCs as photon counting devices. It then describes our fabrication of a prototype detector consisting of a MPPC optically coupled with a Ce: GAGG scintillator. We obtained average FVVHM energy resolutions o17,3% (15 mu M) and 6.7% (new-50 [iri), as compared Lo 6.9% (old-50 mu M) for 662-key gamma rays from the Cs-137 source, as measured at 20 degrees C. Moreover, the number of fired pixels for 662-keV gamma rays increased by 30% for the new-50 mu m (as compared to the old-50 mu m). We confirmed that the low energy threshold improved from 10 kV to 4 keY, when using the latest MPPC device (new-50 pm). We also confirmed that the timing resolution of the new MPPC is 50 ps or even better, as compared to 89 ps of the old MPPC. The results thus confirm that these new types of IVIPPCs are promising for various applications as scintillation detectors. (C) 2014 Elsevier B.V. All rights reserved.

DOI

Scopus

5

被引用数

(Scopus)
The spectrum and morphology of the Fermi bubbles

M. Ackermann, A. Albert, W. B. Atwood, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, R. Bellazzini, E. Bissaldi, R. D. Blandford, E. D. Bloom, E. Bottacini, T. J. Brandt, J. Bregeon, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, M. Caragiulo, P. A. Caraveo, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, J. Chiang, G. Chiaro, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, S. Cutini, F. D'Ammando, A. De Angelis, F. De Palma, C. D. Dermer, S. W. Digel, L. Di Venere, E. Do Couto E Silva, P. S. Drell, C. Favuzzi, E. C. Ferrara, W. B. Focke, A. Franckowiak, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, G. Godfrey, G. A. Gomez-Vargas, I. A. Grenier, S. Guiriec, D. Hadasch, A. K. Harding, E. Hays, J. W. Hewitt, X. Hou, T. Jogler, G. Jóhannesson, A. S. Johnson, W. N. Johnson, T. Kamae, J. Kataoka, J. Knödlseder, D. Kocevski, M. Kuss, S. Larsson, L. Latronico, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, D. Malyshev, A. Manfreda, F. Massaro, M. Mayer, M. N. Mazziotta, J. E. McEnery, P. F. Michelson, W. Mitthumsiri, T. Mizuno, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, R. Nemmen, E. Nuss, T. Ohsugi, N. Omodei, M. Orienti, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta

Astrophysical Journal 793 ( 1 ) 2014年09月

　概要を見る

The Fermi bubbles are two large structures in the gamma-ray sky extending to 55° above and below the Galactic center. We analyze 50 months of Fermi Large Area Telescope data between 100 MeV and 500 GeV above 10° in Galactic latitude to derive the spectrum and morphology of the Fermi bubbles. We thoroughly explore the systematic uncertainties that arise when modeling the Galactic diffuse emission through two separate approaches. The gamma-ray spectrum is well described by either a log parabola or a power law with an exponential cutoff. We exclude a simple power law with more than 7σ significance. The power law with an exponential cutoff has an index of 1.9 ± 0.2 and a cutoff energy of 110 ± 50 GeV. We find that the gamma-ray luminosity of the bubbles is erg s-1. We confirm a significant enhancement of gamma-ray emission in the southeastern part of the bubbles, but we do not find significant evidence for a jet. No significant variation of the spectrum across the bubbles is detected. The width of the boundary of the bubbles is estimated to be deg. Both inverse Compton (IC) models and hadronic models including IC emission from secondary leptons fit the gamma-ray data well. In the IC scenario, synchrotron emission from the same population of electrons can also explain the WMAP and Planck microwave haze with a magnetic field between 5 and 20 μG.

DOI

Scopus

272

被引用数

(Scopus)
Pre-flight performance of a micro-satellite TSUBAME for X-ray polarimetry of gamma-ray bursts

Yatsu Yoichi, Ito Kei, Kurita Shin, Arimoto Makoto, Kawai Nobuyuki, Matsushita Masanori, Kawajiri Shota, Kitamura Shogo, Matunaga Saburo, Kimura Shin'ichi, Kataoka Jun, Nakamori Takeshi, Kubo Sin

SPACE TELESCOPES AND INSTRUMENTATION 2014: ULTRAVIOLET TO GAMMA RAY 9144 2014年07月

DOI

Scopus

7

被引用数

(Scopus)
EXTREME BLAZARS STUDIED WITH FERMI-LAT AND SUZAKU: 1ES 0347-121 AND BLAZAR CANDIDATE HESS J1943+213

Tanaka, Y. T, Stawarz, L, Finke, J, Cheung, C. C, Dermer, C. D, Kataoka, J, Bamba, A, Dubus, G, De Naurois, M, Wagner, S. J

ASTROPHYSICAL JOURNAL 787 ( 2 ) 2014年06月 [査読有り]

　概要を見る

We report on our study of high-energy properties of two peculiar TeV emitters: the extreme blazar" 1ES 0347-121 and the "extreme blazar candidate" HESS J1943+213 located near the Galactic plane. Both objects are characterized by quiescent synchrotron emission with flat spectra extending up to the hard X-ray range, and both were reported to be missing GeV counterparts in the Fermi Large Area Telescope (LAT) two-year Source Catalog. We analyze a 4.5 yr accumulation of the Fermi-LAT data, resulting in the detection of 1ES 0347-121 in the GeV band, as well as in improved upper limits for HESS J1943+213. We also present the analysis results of newly acquired Suzaku data for HESS J1943+213. The X-ray spectrum is well represented by a single power law extending up to 25 keV with photon index 2.00 +/- 0.02 and a moderate absorption in excess of the Galactic value, which is in agreement with previous X-ray observations. No short-term X-ray variability was found over the 80 ks duration of the Suzaku exposure. Under the blazar hypothesis, we modeled the spectral energy distributions of 1ES 0347-121 and HESS J1943+213, and we derived constraints on the intergalactic magnetic fie

DOI

Scopus

25

被引用数

(Scopus)
Search for cosmic-ray-induced gamma-ray emission in galaxy clusters

M. Ackermann, M. Ajello, A. Albert, A. Allafort, W. B. Atwood, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, E. D. Bloom, E. Bonamente, E. Bottacini, T. J. Brandt, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, E. Cavazzuti, R. C.G. Chaves, J. Chiang, G. Chiaro, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, F. D'Ammando, A. De Angelis, F. De Palma, C. D. Dermer, S. W. Digel, P. S. Drell, A. Drlica-Wagner, C. Favuzzi, A. Franckowiak, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, G. Godfrey, G. A. Gomez-Vargas, I. A. Grenier, S. Guiriec, M. Gustafsson, D. Hadasch, M. Hayashida, J. Hewitt, R. E. Hughes, T. E. Jeltema, G. Jóhannesson, A. S. Johnson, T. Kamae, J. Kataoka, J. Knödlseder, M. Kuss, J. Lande, S. Larsson, L. Latronico, M. Llena Garde, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, M. Mayer, M. N. Mazziotta, J. E. McEnery, P. F. Michelson, W. Mitthumsiri, T. Mizuno, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, R. Nemmen, E. Nuss, T. Ohsugi, M. Orienti, E. Orlando, J. F. Ormes, J. S. Perkins, M. Pesce-Rollins, F. Piron, G. Pivato, S. Rainò, R. Rando, M. Razzano, S. Razzaque, A. Reimer, O. Reimer, J. Ruan, M. Sánchez-Conde

Astrophysical Journal 787 ( 1 ) 2014年05月

　概要を見る

Current theories predict relativistic hadronic particle populations in clusters of galaxies in addition to the already observed relativistic leptons. In these scenarios hadronic interactions give rise to neutral pions which decay into γ rays that are potentially observable with the Large Area Telescope (LAT) on board the Fermi space telescope. We present a joint likelihood analysis searching for spatially extended γ-ray emission at the locations of 50 galaxy clusters in four years of Fermi-LAT data under the assumption of the universal cosmic-ray (CR) model proposed by Pinzke & Pfrommer. We find an excess at a significance of 2.7σ, which upon closer inspection, however, is correlated to individual excess emission toward three galaxy clusters: A400, A1367, and A3112. We discuss these cases in detail and conservatively attribute the emission to unmodeled background systems (for example, radio galaxies within the clusters).Through the combined analysis of 50 clusters, we exclude hadronic injection efficiencies in simple hadronic models above 21% and establish limits on the CR to thermal pressure ratio within the virial radius, R 200, to be below 1.25%-1.4% depending on the morphological classification. In addition, we derive new limits on the γ-ray flux from individual clusters in our sample. © 2014. The American Astronomical Society. All rights reserved.

DOI

Scopus

126

被引用数

(Scopus)
Contemporaneous observations of the radio galaxy NGC 1275 from radio to very high energy γ-rays

J. Aleksić, S. Ansoldi, L. A. Antonelli, P. Antoranz, A. Babic, P. Bangale, U. Barres De Almeida, J. A. Barrio, J. Becerra González, W. Bednarek, K. Berger, E. Bernardini, A. Biland, O. Blanch, R. K. Bock, S. Bonnefoy, G. Bonnoli, F. Borracci, T. Bretz, E. Carmona, A. Carosi, D. Carreto Fidalgo, P. Colin, E. Colombo, J. L. Contreras, J. Cortina, S. Covino, P. Da Vela, F. Dazzi, A. De Angelis, G. De Caneva, B. De Lotto, C. Delgado Mendez, M. Doert, A. Domínguez, D. Dominis Prester, D. Dorner, M. Doro, S. Einecke, D. Eisenacher, D. Elsaesser, E. Farina, D. Ferenc, M. V. Fonseca, L. Font, K. Frantzen, C. Fruck, R. J. García López, M. Garczarczyk, D. Garrido Terrats, M. Gaug, G. Giavitto, N. Godinović, A. González Muñoz, S. R. Gozzini, A. Hadamek, D. Hadasch, A. Herrero, D. Hildebrand, J. Hose, D. Hrupec, W. Idec, V. Kadenius, H. Kellermann, M. L. Knoetig, J. Krause, J. Kushida, A. La Barbera, D. Lelas, N. Lewandowska, E. Lindfors, S. Lombardi, M. López, R. López-Coto, A. López-Oramas, E. Lorenz, I. Lozano, M. Makariev, K. Mallot, G. Maneva, N. Mankuzhiyil, K. Mannheim, L. Maraschi, B. Marcote, M. Mariotti, M. Martínez, D. Mazin, U. Menzel, M. Meucci, J. M. Miranda, R. Mirzoyan, A. Moralejo, P. Munar-Adrover, D. Nakajima, A. Niedzwiecki, K. Nilsson, N. Nowak, R. Orito, A. Overkemping, S. Paiano

Astronomy and Astrophysics 564 2014年04月

　概要を見る

Aims. The radio galaxy NGCâ‰ 1275, recently identified as a very high energy (VHE, >100 GeV) γ-ray emitter by MAGIC, is one of the few non-blazar active galactic nuclei detected in the VHE regime. The purpose of this work is to better understand the origin of the γ-ray emission and locate it within the galaxy. Methods. We studied contemporaneous multifrequency observations of NGCâ‰ 1275 and modeled the overall spectral energy distribution. We analyzed unpublished MAGIC observations carried out between October 2009 and February 2010, and the previously published observations taken between August 2010 and February 2011. We studied the multiband variability and correlations by analyzing data of Fermi-LAT in the 100 MeV-100 GeV energy band, as well as Chandra (X-ray), KVA (optical), and MOJAVE (radio) data taken during the same period. Results. Using customized Monte Carlo simulations corresponding to early MAGIC stereoscopic data, we detect NGCâ‰ 1275 also in the earlier MAGIC campaign. The flux level and energy spectra are similar to the results of the second campaign. The monthly light curve above 100 GeV shows a hint of variability at the 3.6σ level. In the Fermi-LAT band, both flux and spectral shape variabilities are reported. The optical light curve is also variable and shows a clear correlation with the γ-ray flux above 100 MeV. In radio, three compact components are resolved in the innermost part of the jet. One of these components shows a similar trend as the Fermi-LAT and KVA light curves. The γ-ray spectra measured simultaneously with MAGIC and Fermi-LAT from 100 MeV to 650 GeV can be well fitted either by a log-parabola or by a power-law with a subexponential cutoff for the two observation campaigns. A single-zone synchrotron-self-Compton model, with an electron spectrum following a power-law with an exponential cutoff, can explain the broadband spectral energy distribution and the multifrequency behavior of the source. However, this model suggests an untypical low bulk-Lorentz factor or a velocity alignment closer to the line of sight than the parsec-scale radio jet. © 2014 ESO.

DOI

Scopus

55

被引用数

(Scopus)
Development of a Prototype Detector Using APD-Arrays Coupled With Pixelized Ce:GAGG Scintillator for High Resolution Radiation Imaging

Kei Kamada, Kenji Shimazoe, Shigeki Ito, Masao Yoshino, Takanori Endo, Kousuke Tsutsumi, Jun Kataoka, Shunsuke Kurosawa, Yuui Yokota, Hiroyuki Takahashi, Akira Yoshikawa

IEEE TRANSACTIONS ON NUCLEAR SCIENCE 61 ( 1 ) 348 - 352 2014年02月 [査読有り]

　概要を見る

A novel digital PET scanner based on Time over Threshold method is developed. The positron emission tomography (PET) is composed of 144channel Ce:Gd3Al2Ga3O12 (GAGG)-Avaranche photodiode (APD) detector arrays individually coupled with custom designed Time over Threshold (ToT) application-specific integrated circuit (ASIC) to realize the high count rate and good spatial resolution. Such an imaging system provides a simple front-end circuit and flexible digital signal processing like multiplexing such as a pulse train method. The measured energy resolution of the detector system was 6.7% for the 511 keV peak, and 4.25 ns time resolution was measured with a single detector module. The measured spatial resolution for a point source was 1.37 mm FWHM for our initial data with a columnar Na-22 source.

DOI

Scopus

18

被引用数

(Scopus)
Observational aspects of AGN jets at high energy

Jun Kataoka

Proceedings of the International Astronomical Union 10 ( S313 ) 1 - 11 2014年

　概要を見る

For the last two decades, significant and dramatic progress has been made in understanding astrophysical jet sources, particularly in the X-ray and gamma-ray energy bands. For example, the Chandra X-ray observatory reveals a number of AGN jets extending from kpc to Mpc scales. More recently, the Fermi Gamma-ray Space Telescopes launched in 2008 started monitoring the gamma-ray sky with excellent sensitivity of about ten times greater than that of EGRET onboard CGRO, and has detected more than 2, 000 sources (mostly AGNs) as of 2014. Moreover, Fermi-LAT has discovered gamma-ray emissions not only from blazars but from a dozen radio galaxies not previously known to emit gamma-rays. Closer to home, the Fermi-bubbles were discovered to extend 50 degrees above and below the Galactic center. These large scale diffuse gamma-ray structures are similar in structure to AGN lobes such as those seen in Cen A and provide evidence for past activity in our Galactic center. In this review, I will first summarize recent highlights of large scale jets in radio galaxies, specifically resolved by the Chandra X-ray observatory. Next I will move on to the gamma-ray sky to present some highlights from Fermi-LAT observations of "misaligned" blazars, namely radio galaxies. I will discuss a unification scheme connecting blazars and misaligned radio galaxies. In the last part, I will also briefly comment on recent multiband observations of the Fermi-bubble and possible impacts on the AGN jet physics in the near future.

DOI
ASTRO-H White Paper - Plasma Diagnostic and Dynamics of the Galactic Center Region

K. Koyama, J. Kataoka, M. Nobukawa, H. Uchiyama, S. Nakashima, F. Aharonian, M. Chernyakova, Y. Ichinohe, K. K. Nobukawa, Y. Maeda, H. Matsumoto, H. Murakami, C. Ricci, L. Stawarz, T. Tanaka, T. G. Tsuru, S. Watanabe, S. Yamauchi, T. Yuasa, for the ASTRO-H, Science Working Group

arXiv 2014年
Development and verification of signal processing system of BGO active shield onboard Astro-H

Masanori Ohno, Shin'ya Tokuda, Takafumi Kawano, Shunya Furui, Ikumi Edahiro, Hiromitsu Takahashi, Kunihiro Goto, Yasushi Fukazawa, Hiroaki Murakami, Syogo Kobayashi, Soki Sakurai, Makoto Sasano, Shunsuke Torii, Toshio Nakano, Ko Ono, Kazuma Miyake, Terukazu Nishida, Kazuhiro Nakazawa, Kazuo Makishima, Kouichi Hagino, Takayuki Yuasa, Hirokazu Odaka, Rie Sato, Shin Watanabe, Motohide Kokubun, Tadayuki Takahashi, Goro Sato, Jun Kataoka, Tatsuhiko Saito, Kazutaka Yamaoka, Hiroyasu Tajima, Yoichi Yatsu, Takeshi Nakamori, Hideki Uchiyama, Daisuke Yonetoku

SPACE TELESCOPES AND INSTRUMENTATION 2014: ULTRAVIOLET TO GAMMA RAY 9144 2014年 [査読有り]

　概要を見る

The hard X-ray imager (HXI) and soft gamma-ray detector (SGD) onboard Astro-H observe astronomical objects with high sensitivity in the hard X-ray (5-80 keV) and soft gamma-ray (40-600 keV) energy bands. To achieve this high sensitivity, background rejection is essential, and these detectors are surrounded by large and thick bismuth germinate scintillators as an active shield. We have developed adequate trigger logic for both the HXI and SGD to process signals from main detector and BGO shield simultaneously and then we optimized the trigger delay and width, with consideration of the trigger latch efficiency. The shield detector system performs well, even after it is assembled as the HXI sensor. The energy threshold maintains the same level as that observed during the prototype development phase, and the experimental room background level of the main detector is successfully reduced by our optimized trigger timing.

DOI

Scopus

9

被引用数

(Scopus)
Development of the camera for the Large Size Telescopes of the Cherenkov Telescope Array

Y. Inome, G. Ambrosi, Y. Awane, H. Baba, A. Bamba, M. Barcelo, U. Barres de Almeida, J. A. Barrio, O. Blanch Bigas, J. Boix, L. Brunetti, E. Carmona, E. Chabanne, M. Chikawa, N. Cho, P. Colin, J. L. Conteras, J. Cortina, F. Dazzi, A. Deangelis, G. Deleglise, C. Delgado, C. Diaz, F. Dubois, A. Fiasson, D. Fink, N. Fouque, L. Freixas, C. Fruck, A. Gadola, R. Garcia, D. Gascon, N. Geffroy, N. Giglietto, F. Giordano, F. Granena, S. Gunji, R. Hagiwara, N. Hamer, Y. Hanabata, T. Hassan, K. Hatanaka, T. Haubold, M. Hayashida, R. Hermel, D. Herranz, K. Hirotani, J. Hose, D. Hugh, S. Inoue, Y. Inoue, K. Ioka, C. Jablonski, M. Kagaya, H. Katagiri, J. Kataoka, H. Kellermann, T. Kishimoto, M. Knoetig, K. Kodani, K. Kohri, T. Kojima, Y. Konno, S. Koyama, H. Kubo, J. Kushida, G. Lamanna, T. Le Flour, M. Lopez-Moya, R. Lopez, E. Lorenz, P. Majumdar, A. Manalaysay, M. Mariotti, G. Martinez, M. Martinez, S. Masuda, S. Matsuoka, D. Mazin, U. Menzel, J. M. Miranda, R. Mirzoyan, I. Monteiro, A. Moralejo, K. Murase, S. Nagataki, T. Nagayoshi, D. Nakajima, T. Nakamori, K. Nishijima, K. Noda, A. Nozato, M. Ogino, Y. Ohira, M. Ohishi, H. Ohoka, A. Okumura, S. Ono, R. Orito, J. L. Panazol, D. Paneque, R. Paoletti, J. M. Paredes, G. Pauletta, S. Podkladkin, J. Prast, R. Rando, O. Reimann, M. Ribo, S. Rosier-Lees, K. Saito, T. Saito, Y. Saito, N. Sakaki, R. Sakonaka, A. Sanuy, M. Sawada, V. Scalzotto, S. Schultz, T. Schweizer, T. Shibata, S. Shu, J. Sieiro, V. Stamatescu, S. Steiner, U. Straumann, R. Sugawara, H. Tajima, H. Takami, M. Takahashi, S. Tanaka, M. Tanaka, L. A. Tejedor, Y. Terada, M. Teshima, Y. Tomono, T. Totani, T. Toyama, Y. Tsubone, Y. Tsuchiya, S. Tsujimoto, H. Ueno, K. Umehara, Y. Umetsu, A. Vollhardt, R. Wagner, H. Wetteskind, T. Yamamoto, R. Yamazaki, A. Yoshida, T. Yoshida, T. Yoshikoshi

ADVANCES IN OPTICAL AND MECHANICAL TECHNOLOGIES FOR TELESCOPES AND INSTRUMENTATION 9151 914542 - 8pp 2014年

　概要を見る

The Large Size Telescopes, LSTs, located at the center of the Cherenkov Telescope Array, CTA, will be sensitive for low energy gamma-rays. The camera on the LST focal plane is optimized to detect low energy events based on a high photon detection efficiency and high speed electronics. Also the trigger system is designed to detect low energy showers as much as possible. In addition, the camera is required to work stably without maintenance in a few tens of years. In this contribution we present the design of the camera for the first LST and the status of its development and production.

DOI

Scopus

6

被引用数

(Scopus)
Soft Gamma-ray Detector (SGD) onboard the ASTRO-H

Fukazawa Yasushi, Tajima Hiroyasu, Watanabe Shin, Blandford Roger, Hayashi Katsuhiro, Harayama Atsushi, Kataoka Jun, Kawaharada Madoka, Kokubun Motohide, Laurent Philippe, Lebrun Francois, Limousin Olivier, Madejski Grzegorz M, Makishima Kazuo, Mizuno Tsunefumi, Mori Kunishiro, Nakamori Takeshi, Nakazawa Kazuhiro, Noda Hirofumi, Odaka Hirokazu, Ohno Masanori, Ohta Masayuki, Saito Shin'ya, Sato Goro, Sato Rie, Takeda Shin'ichiro, Takahashi Hiromitsu, Takahashi Tadayuki, Tanaka Yasuyuki, Terada Yukikatsu, Uchiyama Hideki, Uchiyama Yasunobu, Yamaoka Kazutaka, Yatsu Yoichi, Yonetoku Daisuke, Yuasa Takayuki

SPACE TELESCOPES AND INSTRUMENTATION 2014: ULTRAVIOLET TO GAMMA RAY 9144 2014年 [査読有り]

DOI

Scopus

18

被引用数

(Scopus)
The hard X-ray imager (HXI) for the ASTRO-H mission

Sato G, Kokubun M, Nakazawa K, Enoto T, Fukazawa Y, Harayama A, Hayashi K, Kataoka J, Katsuta J, Kawaharada M, Laurent P, Lebrun F, Limousin O, Makishima K, Mizuno T, Mori K, Nakamori T, Noda H, Odaka H, Ohno M, Ohta M, Saito S, Sato R, Tajima H, Takahashi H, Takahashi T, Takeda S, Terada Y, Uchiyama H, Uchiyama Y, Watanabe S, Yamaoka K, Yatsu Y, Yuasa T

Proceedings of SPIE - The International Society for Optical Engineering 9144 2014年 [査読有り]

DOI

Scopus

23

被引用数

(Scopus)
大面積MPPC array を用いた放射線検出器の最前線

片岡淳

放射線（応用物理学会・放射線分科会） 39 ( 3 ) 117 - 126 2014年

CiNii
Evaluation of the performance limit of MPPC for ToF-PET

Takayuki Tsujikawa, Jun Kataoka, Takahiro Ambe, Takuya Fujita, Yota Kurei, Goro Sato, Hirolazu Ikeda

2014 IEEE NUCLEAR SCIENCE SYMPOSIUM AND MEDICAL IMAGING CONFERENCE (NSS/MIC) 2014年 [査読有り]

　概要を見る

In recent years, multi-pixel photon counters (MP-PCs) have been actively studied for use in a module for such next-generation PET systems as MRI-PET, DoI-PET, and ToF-PET scanners. In particular, Time of Flight (ToF) measurement is a challenging approach to identify the position of a gamma-ray source, according to differences in the arrival times of annihilation gamma rays after positron decay. Several simulations suggest a substantial improvement in the signal-to-noise ratio of PET images when using ToF information. However, ToF-PET performance is determined by the time resolution of a gamma-ray sensor (including scintillators, photo-sensors and readout electronics) as a whole, thus making it often difficult to achieve ToF resolution as good as 500 ps (FWHM) in actual PET systems. This paper describes our development of a new method of ToF measurement using MPPC-based scintillation detectors. We showed that our method effectively reduces the contamination of dark noise, and minimizes the effects of time walk and timing jitter. The best ToF resolution of 213 ps (FWHM) was achieved by coupling 3x3x10 mm(3) Ce:LYSO crystal with a 3x3 mm(2) pixel detector. We conclude by commenting on our ultra-fast ASIC for 16-ch MPPC readout as pertaining to future applications in MPPC-PET scanners with ToF measurement capability.

DOI

Scopus
The first FERMI-LAT catalog of sources above 10 GeV

M. Ackermann, M. Ajello, A. Allafort, W. B. Atwood, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, A. Belfiore, R. Bellazzini, E. Bernieri, E. Bissaldi, E. D. Bloom, E. Bonamente, T. J. Brandt, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, R. Campana, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, R. C.G. Chaves, A. Chekhtman, C. C. Cheung, J. Chiang, G. Chiaro, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, S. Cutini, F. D'Ammando, A. De Angelis, F. De Palma, C. D. Dermer, R. Desiante, S. W. Digel, L. Di Venere, P. S. Drell, A. Drlica-Wagner, C. Favuzzi, S. J. Fegan, E. C. Ferrara, W. B. Focke, P. Fortin, A. Franckowiak, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, G. Godfrey, G. A. Gomez-Vargas, I. A. Grenier, S. Guiriec, D. Hadasch, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, J. Hewitt, A. B. Hill, D. Horan, R. E. Hughes, T. Jogler, G. Jóhannesson, A. S. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, J. Kataoka, T. Kawano, J. Knödlseder, M. Kuss, J. Lande, S. Larsson, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, E. Massaro, M. Mayer

Astrophysical Journal, Supplement Series 209 ( 2 ) 2013年12月

　概要を見る

We present a catalog of γ-ray sources at energies above 10 GeV based on data from the Large Area Telescope (LAT) accumulated during the first 3 yr of the Fermi Gamma-ray Space Telescope mission. The first Fermi-LAT catalog of >10 GeV sources (1FHL) has 514 sources. For each source we present location, spectrum, a measure of variability, and associations with cataloged sources at other wavelengths. We found that 449 (87%) could be associated with known sources, of which 393 (76% of the 1FHL sources) are active galactic nuclei. Of the 27 sources associated with known pulsars, we find 20 (12) to have significant pulsations in the range >10 GeV (>25 GeV). In this work we also report that, at energies above 10 GeV, unresolved sources account for 27% ± 8% of the isotropic γ-ray background, while the unresolved Galactic population contributes only at the few percent level to the Galactic diffuse background. We also highlight the subset of the 1FHL sources that are best candidates for detection at energies above 50-100 GeV with current and future ground-based γ-ray observatories. © 2013. The American Astronomical Society. All rights reserved..

DOI

Scopus

200

被引用数

(Scopus)
Handy Compton camera using 3D position-sensitive scintillators coupled with large-area monolithic MPPC arrays

J. Kataoka, A. Kishimoto, T. Nishiyama, T. Fujita, K. Takeuchi, T. Kato, T. Nakamori, S. Ohsuka, S. Nakamura, M. Hirayanagi, S. Adachi, T. Uchiyama, K. Yamamoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 732 403 - 407 2013年12月

　概要を見る

The release of radioactive isotopes (mainly Cs-137, Cs-134 and till) from the crippled Fukushima Daiichi Nuclear Plant remains a serious problem in japan. To help identify radiation hotspots and ensure effective decontamination operation, we are developing a novel Compton camera weighting only 1 kg and measuring just similar to 10 cm(2) in size. Despite its compactness, the camera realizes a wide 180 degrees field of vision with a sensitivity about 50 times superior to other cameras being tested in Fukushima. We expect that a hotspot producing a 5 mu Sv/h dose at a distance of 3 m can be imaged every 10 s, with angular resolution better than 10 degrees (FWHM). The 3D position sensitive scintillators and thin monolithic MPPC arrays are the key technologies developed here. By measuring the pulse height ratio of MPPC-arrays coupled at both ends of a Ce:GAGG scintillator block, the depth of interaction (DOI) is obtained for incident gamma rays as well as the usual 2D positions, with accuracy better than 2 mm. By using two identical 10 mm cubic Ce:GAGG scintillators as a scatterer and an absorber, we confirmed that the 3D configuration works well as a high resolution gamma camera, and also works as spectrometer achieving typical energy resolution of 9.8% (FWHM) for 662 keV gamma rays. We present the current status of the prototype camera (weighting 1.5 kg and measuring 8.5 x 14 x 16 cm(3) in size) being fabricated by Hamamatsu Photonics K. K. Although the camera still operates in non-DOI mode, angular resolution as high as 14 degrees (FWHM) was achieved with an integration time of 30s for the assumed hotspot described above. (C) 2013 Elsevier B.V. All tights reserved.

DOI

Scopus

126

被引用数

(Scopus)
SUZAKU OBSERVATIONS OF THE DIFFUSE X-RAY EMISSION ACROSS THE FERMI BUBBLES' EDGES

J. Kataoka, M. Tahara, T. Totani, Y. Sofue, L. Stawarz, Y. Takahashi, Y. Takeuchi, H. Tsunemi, M. Kimura, Y. Takei, C. C. Cheung, Y. Inoue, T. Nakamori

ASTROPHYSICAL JOURNAL 779 ( 1 ) 2013年12月

　概要を見る

We present Suzaku X-ray observations along two edge regions of the Fermi Bubbles, with eight similar or equal to 20 ks pointings across the northern part of the North Polar Spur (NPS) surrounding the north bubble and six across the southernmost edge of the south bubble. After removing compact X-ray features, diffuse X-ray emission is clearly detected and is well reproduced by a three-component spectral model consisting of unabsorbed thermal emission (temperature kT similar or equal to 0.1 keV) from the Local Bubble, absorbed kT similar or equal to 0.3 keV thermal emission related to the NPS and/or Galactic halo (GH), and a power-law component at a level consistent with the cosmic X-ray background. The emission measure (EM) of the 0.3 keV plasma decreases by similar or equal to 50% toward the inner regions of the northeast bubble, with no accompanying temperature change. However, such a jump in the EM is not clearly seen in the south bubble data. While it is unclear whether the NPS originates from a nearby supernova remnant or is related to previous activity within or around the Galactic center, our Suzaku observations provide evidence that suggests the latter scenario. In the latter framework, the presence of a large amount of neutral matter absorbing the X-ray emission as well as the existence of the kT similar or equal to 0.3 keV gas can be naturally interpreted as a weak shock driven by the bubbles' expansion in the surrounding medium, with velocity v(exp) similar or equal to 300 km s(-1) (corresponding to shock Mach number M similar or equal to 1.5), compressing the GH gas to form the NPS feature. We also derived an upper limit for any non-thermal X-ray emission component associated with the bubbles and demonstrate that, in agreement with the aforementioned findings, the non-thermal pressure and energy estimated from a one-zone leptonic model of its broadband spectrum, are in rough equilibrium with that of the surrounding thermal plasma.

DOI

Scopus

99

被引用数

(Scopus)
3次元位置有感型シンチレータと MPPCアレイを用いた携帯型ガンマ線カメラ

J.Kataoka

Nuclear Instruments and Method, Section-A 732 403 - 407 2013年12月 [査読有り]

DOI

Scopus

126

被引用数

(Scopus)
すざく衛星によるフェルミ・バブルからの拡散X線の観測

J.Kataoka

The Astrophysical Journal 779 ( 1 ) 57 - 72 2013年12月 [査読有り]

DOI

Scopus

99

被引用数

(Scopus)
Erratum: Fermi large area telescope study of cosmic-rays and the interstellar medium in nearby molecular clouds (ApJ (2012) 755 (22))

M. Ackermann, M. Ajello, A. Allafort, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, E. Bottacini, T. J. Brandt, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, G. Busetto, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, C. Cecchi, E. Charles, A. Chekhtman, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, F. D'Ammando, A. De Angelis, F. De Palma, C. D. Dermer, S. W. Digel, E. Do Couto E Silva, P. S. Drell, A. Drlica-Wagner, L. Falletti, C. Favuzzi, S. J. Fegan, E. C. Ferrara, W. B. Focke, Y. Fukazawa, Y. Fukui, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, J. E. Grove, S. Guiriec, D. Hadasch, Y. Hanabata, A. K. Harding, K. Hayashi, D. Horan, X. Hou, R. E. Hughes, R. Itoh, M. S. Jackson, G. Jóhannesson, A. S. Johnson, T. Kamae, H. Katagiri, J. Kataoka, J. Knödlseder, M. Kuss, J. Lande, S. Larsson, S. H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, P. Martin, M. N. Mazziotta, J. E. McEnery, J. Mehault, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia

Astrophysical Journal 778 ( 1 ) 2013年11月

DOI

Scopus

6

被引用数

(Scopus)
The First Fermi-LAT Gamma-Ray Burst Catalog

Ackermann M, Ajello M, Asano K, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Bhat P.~N, Bissaldi E, Bloom E.~D, Bonamente E, Bonnell J, Bouvier A, Brandt T.~J, Bregeon J, Brigida M, Bruel P, Buehler R, Burgess J.~M, Buson S, Byrne D, Caliandro G.~A, Cameron R.~A, Caraveo P.~A, Cecchi C, Charles E, Chaves R.~C.~G, Chekhtman A, Chiang J, Chiaro G, Ciprini S, Claus R, Cohen-Tanugi J, Connaughton V, Conrad J, Cutini S, D'Ammando F, de Angelis A, de Palma F, Dermer C.~D, Desiante R, Digel S.~W, Dingus B.~L, Di Venere L, Drell P.~S, Drlica-Wagner A, Dubois R, Favuzzi C, Ferrara E.~C, Fitzpatrick G, Foley S, Franckowiak A, Fukazawa Y, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Goldstein A, Granot J, Grenier I.~A, Grove J.~E, Gruber D, Guiriec S, Hadasch D, Hanabata Y, Hayashida M, Horan D, Hou X, Hughes R.~E, Inoue Y, Jackson M.~S, Jogler T, J{\'o}hannesson G, Johnson A.~S, Johnson W.~N, Kamae T, Kataoka J, Kawano T, Kippen R.~M, Kn{\"o}dlseder J, Kocevski D, Kouveliotou C, Kuss M, Lande J, Larsson S, Latronico L, Lee S.-H, Longo F, Loparco F, Lovellette M.~N, Lubrano P, Massaro F, Mayer M, Mazziotta M.~N, McBreen S, McEnery J.~E, McGlynn S, Michelson P.~F, Mizuno T, Moiseev A.~A, Monte C, Monzani M.~E, Moretti E, Morselli A, Murgia S, Nemmen R, Nuss E, Nymark T, Ohno M, Ohsugi T, Omodei N, Orienti M, Orlando E, Paciesas W.~S, Paneque D, Panetta J.~H, Pelassa V, Perkins J.~S, Pesce-Rollins M, Piron F, Pivato G, Porter T.~A, Preece R, Racusin J.~L, Rain{\`o} S, Rando R, Rau A, Razzano M, Razzaque S, Reimer A, Reimer O, Reposeur T, Ritz S, Romoli C, Roth M, Ryde F, Saz Parkinson P.~M, Schalk T.~L, Sgr{\`o} C, Siskind E.~J, Sonbas E, Spandre G, Spinelli P, Suson D.~J, Tajima H, Takahashi H, Takeuchi Y, Tanaka Y, Thayer J.~G, Thayer J.~B, Thompson D.~J, Tibaldo L, Tierney D, Tinivella M, Torres D.~F, Tosti G, Troja E, Tronconi V, Usher T.~L, Vandenbroucke J, van der Horst A.~J, Vasileiou V, Vianello G, Vitale V, von Kienlin A, Winer B.~L, Wood K.~S, Wood M, Xiong S, Yang Z

The Astrophysical Journal Supplement 209 ( 1 ) 11 2013年11月 [査読有り]

DOI

Scopus

269

被引用数

(Scopus)
THE SECOND FERMI LARGE AREA TELESCOPE CATALOG OF GAMMA-RAY PULSARS

A. A. Abdo, M. Ajello, A. Allafort, L. Baldini, J. Ballet, G. Barbiellini, M. G. Baring, D. Bastieri, A. Belfiore, R. Bellazzini, B. Bhattacharyya, E. Bissaldi, E. D. Bloom, E. Bonamente, E. Bottacini, T. J. Brandt, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, M. Burgay, T. H. Burnett, G. Busetto, S. Buson, G. A. Caliandro, R. A. Cameron, F. Camilo, P. A. Caraveo, J. M. Casandjian, C. Cecchi, Oe . Celik, E. Charles, S. Chaty, R. C. G. Chaves, A. Chekhtman, A. W. Chen, J. Chiang, G. Chiaro, S. Ciprini, R. Claus, I. Cognard, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, S. Cutini, F. D'Ammando, A. De Angelis, M. E. DeCesar, A. De Luca, P. R. Den Hartog, F. De Palma, C. D. Dermer, G. Desvignes, S. W. Digel, L. Di Venere, P. S. Drell, A. Drlica-Wagner, R. Dubois, D. Dumora, C. M. Espinoza, L. Falletti, C. Favuzzi, E. C. Ferrara, W. B. Focke, A. Franckowiak, P. C. C. Freire, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, S. Germani, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, E. V. Gotthelf, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, D. Hadasch, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, J. Hessels, J. Hewitt, A. B. Hill, D. Horan, X. Hou, R. E. Hughes, M. S. Jackson, G. H. Janssen, T. Jogler, G. Johannesson, R. P. Johnson, A. S. Johnson, T. J. Johnson, W. N. Johnson, S. Johnston, T. Kamae, J. Kataoka, M. Keith, M. Kerr, J. Knoedlseder, M. Kramer, M. Kuss, J. Lande, S. Larsson, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, A. G. Lyne, R. N. Manchester, M. Marelli, F. Massaro, M. Mayer, M. N. Mazziotta, J. E. McEnery, M. A. McLaughlin, J. Mehault, P. F. Michelson, R. P. Mignani, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, R. Nemmen, E. Nuss, M. Ohno, T. Ohsugi, M. Orienti, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, J. S. Perkins, M. Pesce-Rollins, M. Pierbattista, F. Piron, G. Pivato, H. J. Pletsch, T. A. Porter, A. Possenti, S. Raino, R. Rando, S. M. Ransom, P. S. Ray, M. Razzano, N. Rea, A. Reimer, O. Reimer, N. Renault, T. Reposeur, S. Ritz, R. W. Romani, M. Roth, R. Rousseau, J. Roy, J. Ruan, A. Sartori, P. M. Saz Parkinson, J. D. Scargle, A. Schulz, C. Sgro, R. Shannon, E. J. Siskind, D. A. Smith, G. Spandre, P. Spinelli, B. W. Stappers, A. W. Strong, D. J. Suson, H. Takahashi, J. G. Thayer, J. B. Thayer, G. Theureau, D. J. Thompson, S. E. Thorsett, L. Tibaldo, O. Tibolla, M. Tinivella, D. F. Torres, G. Tosti, E. Troja, Y. Uchiyama, T. L. Usher, J. Vandenbroucke, V. Vasileiou, C. Venter, G. Vianello, V. Vitale, N. Wang, P. Weltevrede, B. L. Winer, M. T. Wolff, D. L. Wood, K. S. Wood, M. Wood, Z. Yang

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES 208 ( 2 ) 17 2013年10月 [査読有り]

　概要を見る

This catalog summarizes 117 high-confidence >= 0.1 GeV gamma-ray pulsar detections using three years of data acquired by the Large Area Telescope (LAT) on the Fermi satellite. Half are neutron stars discovered using LAT data through periodicity searches in gamma-ray and radio data around LAT unassociated source positions. The 117 pulsars are evenly divided into three groups: millisecond pulsars, young radio-loud pulsars, and young radio-quiet pulsars. We characterize the pulse profiles and energy spectra and derive luminosities when distance information exists. Spectral analysis of the off-peak phase intervals indicates probable pulsar wind nebula emission for four pulsars, and off-peak magnetospheric emission for several young and millisecond pulsars. We compare the gamma-ray properties with those in the radio, optical, and X-ray bands. We provide flux limits for pulsars with no observed gamma-ray emission, highlighting a small number of gamma-faint, radio-loud pulsars. The large, varied gamma-ray pulsar sample constrains emission models. Fermi's selection biases complement those of radio surveys, enhancing comparisons with predicted population distributions.

DOI

Scopus

732

被引用数

(Scopus)
MULTIBAND DIAGNOSTICS OF UNIDENTIFIED 1FGL SOURCES WITH SUZAKU AND SWIFT X-RAY OBSERVATIONS

Y. Takeuchi, J. Kataoka, K. Maeda, Y. Takahashi, T. Nakamori, M. Tahara

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES 208 ( 2 ) 25 - 57 2013年10月 [査読有り]

　概要を見る

We have analyzed all the archival X-ray data of 134 unidentified (unID) gamma-ray sources listed in the first Fermi/LAT (1FGL) catalog and subsequently followed up by the Swift/XRT. We constructed the spectral energy distributions (SEDs) from radio to gamma-rays for each X-ray source detected, and tried to pick up unique objects that display anomalous spectral signatures. In these analyses, we target all the 1FGL unID sources, using updated data from the second Fermi/LAT (2FGL) catalog on the Large Area Telescope (LAT) position and spectra. We found several potentially interesting objects, particularly three sources, 1FGL J0022.2-1850, 1FGL J0038.0+1236, and 1FGL J0157.0-5259, which were then more deeply observed with Suzaku as a part of an AO-7 program in 2012. We successfully detected an X-ray counterpart for each source whose X-ray spectra were well fitted by a single power-law function. The positional coincidence with a bright radio counterpart (currently identified as an active galactic nucleus, AGN) in the 2FGL error circles suggests these sources are definitely the X-ray emission from the same AGN, but their SEDs show a wide variety of behavior. In particular, the SED of 1FGL J0038.0+1236 is not easily explained by conventional emission models of blazars. The source 1FGL J0022.2-1850 may be in a transition state between a low-frequency peaked and a high-frequency peaked BL Lac object, and 1FGL J0157.0-5259 could be a rare kind of extreme blazar. We discuss the possible nature of these three sources observed with Suzaku, together with the X-ray identification results and SEDs of all 134 sources observed with the Swift/XRT.

DOI

Scopus

29

被引用数

(Scopus)
高感度かつ携帯可能なガンマ線カメラの開発

片岡淳, 西山徹, 藤田卓也, 武内健士郎, 呉井洋太, 岸本彩, 大須賀慎二, 中村重幸, 平柳通人, 足立俊介, 内山徹也, 加藤卓也, 鈴木裕樹

電気学会研究会資料. NE, 原子力研究会 2013 ( 1 ) 1 - 6 2013年09月

CiNii
CONSTRAINTS ON THE COSMIC-RAY DENSITY GRADIENT BEYOND THE SOLAR CIRCLE FROM FERMI gamma-RAY OBSERVATIONS OF THE THIRD GALACTIC QUADRANT (vol 726, pg 81, 2011)

Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgla, A. W, Brandt T. J, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Dermer C. D, de Palma F, Digel S. W, Drell P. S, Dubois R, Favuzzi C, Ferrara E. C, Focke W. B, Fukazawa Y, Funk S, Fusco P, Gargano F, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashi K, Hayashida M, Hughes R. E, Itoh R, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Llena-Garde M, Longo F, Loparco F, Lovellette M. N, Lubrano P, Makeev A, Martin P, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Nishino S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Ripken J, Sada T, Sadrozinski H. F. -W, Sgro C, Siskind E. J, Spandre G, Spinelli P, Strickman M. S, Strong A. W, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thompson D. J, Tibaldo L, Torres D. F, Tramacere A, Uchiyama Y, Uehara T, Usher T. L, Vandenbroucke J, Vasileiou V, Vilchez N, Vitale V, Vladimirov A. E, Waite A. P, Wang P, Wood K. S, Yang Z, Ziegler M

ASTROPHYSICAL JOURNAL 772 ( 2 ) 2013年08月 [査読有り]

DOI

Scopus

2

被引用数

(Scopus)
X-RAY AND RADIO FOLLOW-UP OBSERVATIONS OF HIGH-REDSHIFT BLAZAR CANDIDATES IN THE FERMI-LAT UNASSOCIATED SOURCE POPULATION

Y. Takahashi, J. Kataoka, K. Niinuma, M. Honma, Y. Inoue, T. Totani, S. Inoue, T. Nakamori, K. Maeda

ASTROPHYSICAL JOURNAL 773 ( 1 ) 36 - 46 2013年08月 [査読有り]

　概要を見る

We report on the results of X-ray and radio follow-up observations of two GeV gamma-ray sources 2FGL J0923.5+1508 and 2FGL J1502.1+5548, selected as candidates for high-redshift blazars from unassociated sources in the Fermi Large Area Telescope Second Source Catalog. We utilize the Suzaku satellite and the VLBI Exploration of Radio Astrometry (VERA) telescopes for X-ray and radio observations, respectively. For 2FGL J0923.5+1508, a possible radio counterpart NVSS J092357+150518 is found at 1.4 GHz from an existing catalog, but we do not detect any X-ray emission from it and derive a flux upper limit F2-8 (keV) < 1.37 x 10(-14) erg cm(-2) s(-1). Radio observations at 6.7 GHz also result in an upper limit of S-6.7 (GHz) < 19 mJy, implying a steep radio spectrum that is not expected for a blazar. On the other hand, we detect X-rays from NVSS J150229+555204, the potential 1.4 GHz radio counterpart of 2FGL J1502.1+5548. The X-ray spectrum can be fitted with an absorbed power-law model with a photon index gamma = 1.8(-0.2)(+0.3) and the unabsorbed flux is F2-8 (keV) = 4.3(-1.0)(+1.1) x 10(-14) erg cm(-2) s(-1). Moreover, we detect unresolved radio emission at 6.7 GHz with flux S-6.7 (GHz) = 30.1 mJy, indicating a compact, flat-spectrum radio source. If NVSS J150229+555204 is indeed associated with 2FGL J1502.1+5548, then we find that its multiwavelength spectrum is consistent with a blazar at redshift z similar to 3-4.

DOI

Scopus

4

被引用数

(Scopus)
Development of Radiation-hardened Multi Pixel Photon Counters

Nakamori, T, Kurei, Y, Takeuchi, K, Saito, T, Kataoka, J, Fujita, T, Kato, T, Sato, K, Yamada, R, Kawabata, N, Kokubun, M

Proceedings of 33rd International Cosmic Ray Conference 2013-October 2013年07月
The Fermi all-sky variability analysis: A list of flaring gamma-ray sources and the search for transients in our galaxy

M. Ackermann, M. Ajello, A. Albert, A. Allafort, E. Antolini, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, R. D. Blandford, E. D. Bloom, E. Bonamente, E. Bottacini, A. Bouvier, T. J. Brandt, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, G. Chiaro, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, S. Cutini, M. Dalton, F. D'Ammando, A. De Angelis, F. De Palma, C. D. Dermer, L. Di Venere, P. S. Drell, A. Drlica-Wagner, C. Favuzzi, S. J. Fegan, E. C. Ferrara, W. B. Focke, A. Franckowiak, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, J. E. Grove, S. Guiriec, D. Hadasch, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, J. Hewitt, A. B. Hill, D. Horan, X. Hou, R. E. Hughes, Y. Inoue, M. S. Jackson, T. Jogler, G. Jóhannesson, W. N. Johnson, T. Kamae, J. Kataoka, T. Kawano, J. Knödlseder, M. Kuss, J. Lande, S. Larsson, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, M. Mayer, M. N. Mazziotta, J. E. McEnery, P. F. Michelson, W. Mitthumsiri, T. Mizuno

Astrophysical Journal 771 ( 1 ) 2013年07月

　概要を見る

In this paper, we present the Fermi All-sky Variability Analysis (FAVA), a tool to systematically study the variability of the gamma-ray sky measured by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. For each direction on the sky, FAVA compares the number of gamma-rays observed in a given time window to the number of gamma-rays expected for the average emission detected from that direction. This method is used in weekly time intervals to derive a list of 215 flaring gamma-ray sources. We proceed to discuss the 27 sources found at Galactic latitudes smaller than 10° and show that, despite their low latitudes, most of them are likely of extragalactic origin. © 2013. The American Astronomical Society. All rights reserved.

DOI

Scopus

56

被引用数

(Scopus)
High resolution phoswich gamma-ray imager utilizing monolithic MPPC arrays with submillimeter pixelized crystals

T. Kato, J. Kataoka, T. Nakamori, A. Kishimoto, S. Yamamoto, K. Sato, Y. Ishikawa, K. Yamamura, N. Kawabata, H. Ikeda, K. Kamada

JOURNAL OF INSTRUMENTATION 8 ( 5 ) P05022 2013年05月 [査読有り]

　概要を見る

We report the development of a high spatial resolution tweezers-type coincidence gamma-ray camera for medical imaging. This application consists of large-area monolithic Multi-Pixel Photon Counters (MPPCs) and submillimeter pixelized scintillator matrices. The MPPC array has 4x4 channels with a three-side buttable, very compact package. For typical operational gain of 7.5x10(5) at + 20 degrees C, gain fluctuation over the entire MPPC device is only +/- 5.6%, and dark count rates (as measured at the 1 p.e. level) amount to <= 400 kcps per channel. We selected Ce-doped (Lu, Y)(2)(SiO4)O (Ce:LYSO) and a brand-new scintillator, Ce-doped Gd3Al2Ga3O12 (Ce:GAGG) due to their high light yield and density. To improve the spatial resolution, these scintillators were fabricated into 15x15 matrices of 0.5x0.5 mm(2) pixels. The Ce: LYSO and Ce: GAGG scintillator matrices were assembled into phosphor sandwich (phoswich) detectors, and then coupled to the MPPC array along with an acrylic light guide measuring 1 mm thick, and with summing operational amplifiers that compile the signals into four position-encoded analog outputs being used for signal readout. Spatial resolution of 1.1 mm was achieved with the coincidence imaging system using a Na-22 point source. These results suggest that the gamma-ray imagers offer excellent potential for applications in high spatial medical imaging.

DOI

Scopus

6

被引用数

(Scopus)
GIANT LOBES OF CENTAURUS A RADIO GALAXY OBSERVED WITH THE SUZAKU X-RAY SATELLITE

Stawarz, L, Tanaka, Y. T, Madejski, G, O'Sullivan, S. P, Cheung, C. C, Feain, I. J, Fukazawa, Y, Gandhi, P, Hardcastle, M. J, Kataoka, J

ASTROPHYSICAL JOURNAL 766 ( 1 ) 2013年03月 [査読有り]

　概要を見る

We report on Suzaku observations of selected regions within the southern giant lobe of the radio galaxy Centaurus A. In our analysis we focus on distinct X-ray features detected with the X-ray Imaging Spectrometer within the range 0.5-10 keV, some of which are likely associated with fine structure of the lobe revealed by recent high-quality radio intensity and polarization maps. With the available photon statistics, we find that the spectral properties of the detected X-ray features are equally consistent with thermal emission from hot gas with temperatures kT > 1 keV, or with a power-law radiation continuum characterized by photon indices Gamma similar to 2.0 +/- 0.5. However, the plasma parameters implied by these different models favor a synchrotron origin for the analyzed X-ray spots, indicating that a very efficient acceleration of electrons up to greater than or similar to 10 TeV energies is taking place within the giant structure of Centaurus A, albeit only in isolated and compact regions associated with extended and highly polarized radio filaments. We also present a detailed analysis of the diffuse X-ray emission filling the whole field of view of the instrument, resulting

DOI

Scopus

33

被引用数

(Scopus)
Introducing the CTA concept

Acharya, B. S., Actis, M., Aghajani, T., Agnetta, G., Aguilar, J., Aharonian, F., Ajello, M., Akhperjanian, A., Alcubierre, M., Aleksić, J., Alfaro, R., Aliu, E., Allafort, A. J., Allan, D., Allekotte, I., Amato, E., Anderson, J., Angüner, E. O., Antonelli, L. A., Antoranz, P. Aravantinos, A., Arlen, T., Armstrong, T., Arnaldi, H., Arrabito, L., Asano, K., Ashton, T., Asorey, H. G., Awane, Y., Baba, H., Babic, A., Baby, N., Bähr, J., Bais, A., Baixeras, C., Bajtlik, S., Balbo, M., Balis, D., Balkowski, C., Bamba, A., Bandiera, R., Barber, A., Barbier, C., Barceló, M., Barnacka, A., Barnstedt, J., Barres de Almeida, U., Barrio, J. A., Basili, A., Basso, S., Bastieri, D., Bauer, C., Baushev, A., Becerra, J., Becherini, Y., Bechtol, K. C., Becker Tjus, J., Beckmann, V., Bednarek, W., Behera, B., Belluso, M., Benbow, W., Berdugo, J., Berger, K., Bernard, F., Bernardino, T., Bernlöhr, K., Bhat, N., Bhattacharyya, S., Bigongiari, C., Biland, A., Billotta, S., Bird, T., Birsin, E., Bissaldi, E., Biteau, J., Bitossi, M., Blake, S., Blanch Bigas, O., Blasi, P., Bobkov, A., Boccone, V., Boettcher, M., Bogacz, L., Bogart, J., Bogdan, M., Boisson, C., Boix Gargallo, J., Bolmont, J., Bonanno, G., Bonardi, A., Bonev, T., Bonifacio, P., Bonnoli, G., Bordas, P., Borgland, A., Borkowski, J., Bose, R., Botner, O., Bottani, A., Bouchet, L., Bourgeat, M., Boutonnet, C., Bouvier, A., Brau-Nogué, S., Braun, I., Bretz, T., Briggs, M., Bringmann, T., Brook, P., Brun, P., Brunetti, L., Buanes, T., Buckley, J., Buehler, R., Bugaev, V., Bulgarelli, A., Bulik, T., Busetto, G., Buson, S., Byrum, K., Cailles, M., Cameron, R., Camprecios, J., Canestrari, R., Cantu, S., Capalbi, M., Caraveo, P., Carmona, E., Carosi, A., Carr, J., Carton, P. -H., Casanova, S., Casiraghi, M., Catalano, O., Cavazzani, S., Cazaux, S., Cerruti, M., Chabanne, E., Chadwick, P., Champion, C., Chen, A., Chiang, J., Chiappetti, L., Chikawa, M., Chitnis, V. R., Chollet, F., Chudoba, J., Cieślar, M., Cillis, A., Cohen-Tanugi, J., Colafrancesco, S., Colin, P., Colome, J., Colonges, S., Compin, M., Conconi, P., Conforti, V., Connaughton, V., Conrad, J., Contreras, J. L., Coppi, P., Corona, P., Corti, D., Cortina, J., Cossio, L., Costantini, H., Cotter, G., Courty, B., Couturier, S., Covino, S., Crimi, G., Criswell, S. J., Croston, J., Cusumano, G., Dafonseca, M., Dale, O., Daniel, M., Darling, J., Davids, I., Dazzi, F., De Angelis, A., De Caprio, V., De Frondat, F., de Gouveia Dal Pino, E. M., de la Calle, I., De La Vega, G. A., de los Reyes Lopez, R., De Lotto, B., De Luca, A., de Mello Neto, J. R. T., de Naurois, M., de Oliveira, Y., de Oña Wilhelmi, E., de Souza, V., Decerprit, G., Decock, G., Deil, C., Delagnes, E., Deleglise, G., Delgado, C., Della Volpe, D., Demange, P., Depaola, G., Dettlaff, A., Di Paola, A., Di Pierro, F., Díaz, C., Dick, J., Dickherber, R., Dickinson, H., Diez-Blanco, V., Digel, S., Dimitrov, D., Disset, G., Djannati-Ataï, A., Doert, M., Dohmke, M., Domainko, W., Dominis Prester, D., Donat, A., Dorner, D., Doro, M., Dournaux, J. -L., Drake, G., Dravins, D., Drury, L., Dubois, F., Dubois, R., Dubus, G., Dufour, C., Dumas, D., Dumm, J., Durand, D., Dyks, J., Dyrda, M., Ebr, J., Edy, E., Egberts, K., Eger, P., Einecke, S., Eleftheriadis, C., Elles, S., Emmanoulopoulos, D., Engelhaupt, D., Enomoto, R., Ernenwein, J. -P., Errando, M., Etchegoyen, A., Evans, P., Falcone, A., Fantinel, D., Farakos, K., Farnier, C., Fasola, G., Favill, B., Fede, E., Federici, S., Fegan, S., Feinstein, F., Ferenc, D., Ferrando, P., Fesquet, M., Fiasson, A., Fillin-Martino, E., Fink, D., Finley, C., Finley, J. P., Fiorini, M., Firpo Curcoll, R., Flores, H., Florin, D., Focke, W., Föhr, C., Fokitis, E., Font, L., Fontaine, G., Fornasa, M., Förster, A., Fortson, L., Fouque, N., Franckowiak, A., Fransson, C., Fraser, G., Frei, R., Albuquerque, I. F. M., Fresnillo, L., Fruck, C., Fujita, Y., Fukazawa, Y., Fukui, Y., Funk, S., Gäbele, W., Gabici, S., Gabriele, R., Gadola, A., Galante, N., Gall, D., Gallant, Y., Gámez-García, J., García, B., Garcia López, R., Gardiol, D., Garrido, D., Garrido, L., Gascon, D., Gaug, M., Gaweda, J., Gebremedhin, L., Geffroy, N., Gerard, L., Ghedina, A., Ghigo, M., Giannakaki, E., Gianotti, F., Giarrusso, S., Giavitto, G., Giebels, B., Gika, V., Giommi, P., Girard, N., Giro, E., Giuliani, A., Glanzman, T., Glicenstein, J. -F., Godinovic, N., Golev, V., Gomez Berisso, M., Gómez-Ortega, J., Gonzalez, M. M., González, A., González, F., González Muñoz, A., Gothe, K. S., Gougerot, M., Graciani, R., Grandi, P., Grañena, F., Granot, J., Grasseau, G., Gredig, R., Green, A., Greenshaw, T., Grégoire, T., Grimm, O., Grube, J., Grudzinska, M., Gruev, V., Grünewald, S., Grygorczuk, J., Guarino, V., Gunji, S., Gyuk, G., Hadasch, D., Hagiwara, R., Hahn, J., Hakansson, N., Hallgren, A., Hamer Heras, N., Hara, S., Hardcastle, M. J., Harris, J., Hassan, T., Hatanaka, K., Haubold, T., Haupt, A., Hayakawa, T., Hayashida, M., Heller, R., Henault, F., Henri, G., Hermann, G., Hermel, R., Herrero, A., Hidaka, N., Hinton, J., Hoffmann, D., Hofmann, W., Hofverberg, P., Holder, J., Horns, D., Horville, D., Houles, J., Hrabovsky, M., Hrupec, D., Huan, H., Huber, B., Huet, J. -M., Hughes, G., Humensky, T. B., Huovelin, J., Ibarra, A., Illa, J. M., Impiombato, D., Incorvaia, S., Inoue, S., Inoue, Y., Ioka, K., Ismailova, E., Jablonski, C., Jacholkowska, A., Jamrozy, M., Janiak, M., Jean, P., Jeanney, C., Jimenez, J. J., Jogler, T., Johnson, T., Journet, L., Juffroy, C., Jung, I., Kaaret, P., Kabuki, S., Kagaya, M., Kakuwa, J., Kalkuhl, C., Kankanyan, R., Karastergiou, A., Kärcher, K., Karczewski, M., Karkar, S., Kasperek, J., Kastana, D., Katagiri, H., Kataoka, J., Katarzyński, K., Katz, U., Kawanaka, N., Kellner-Leidel, B., Kelly, H., Kendziorra, E., Khélifi, B., Kieda, D. B., Kifune, T., Kihm, T., Kishimoto, T., Kitamoto, K., Kluźniak, W., Knapic, C., Knapp, J., Knödlseder, J., Köck, F., Kocot, J., Kodani, K., Köhne, J. -H., Kohri, K., Kokkotas, K., Kolitzus, D., Komin, N., Kominis, I., Konno, Y., Köppel, H., Korohoda, P., Kosack, K., Koss, G., Kossakowski, R., Kostka, P., Koul, R., Kowal, G., Koyama, S., Kozioł, J., Krähenbühl, T., Krause, J., Krawzcynski, H., Krennrich, F., Krepps, A., Kretzschmann, A., Krobot, R., Krueger, P., Kubo, H., Kudryavtsev, V. A., Kushida, J., Kuznetsov, A., La Barbera, A., La Palombara, N., La Parola, V., La Rosa, G., Lacombe, K., Lamanna, G., Lande, J., Languignon, D., Lapington, J., Laporte, P., Lavalley, C., Le Flour, T., Le Padellec, A., Lee, S. -H., Lee, W. H., Leigui de Oliveira, M. A., Lelas, D., Lenain, J. -P., Leopold, D. J., Lerch, T., Lessio, L., Lieunard, B., Lindfors, E., Liolios, A., Lipniacka, A., Lockart, H., Lohse, T., Lombardi, S., Lopatin, A., Lopez, M., López-Coto, R., López-Oramas, A., Lorca, A., Lorenz, E., Lubinski, P., Lucarelli, F., Lüdecke, H., Ludwin, J., Luque-Escamilla, P. L., Lustermann, W., Luz, O., Lyard, E., Maccarone, M. C., Maccarone, T. J., Madejski, G. M., Madhavan, A., Mahabir, M., Maier, G., Majumdar, P., Malaguti, G., Maltezos, S., Manalaysay, A., Mancilla, A., Mandat, D., Maneva, G., Mangano, A., Manigot, P., Mannheim, K., Manthos, I., Maragos, N., Marcowith, A., Mariotti, M., Marisaldi, M., Markoff, S., Marszałek, A., Martens, C., Martí, J., Martin, J. -M., Martin, P., Martínez, G., Martínez, F., Martínez, M., Masserot, A., Mastichiadis, A., Mathieu, A., Matsumoto, H., Mattana, F., Mattiazzo, S., Maurin, G., Maxfield, S., Maya, J., Mazin, D., Mc Comb, L., McCubbin, N., McHardy, I., McKay, R., Medina, C., Melioli, C., Melkumyan, D., Mereghetti, S., Mertsch, P., Meucci, M., Michałowski, J., Micolon, P., Mihailidis, A., Mineo, T., Minuti, M., Mirabal, N., Mirabel, F., Miranda, J. M., Mirzoyan, R., Mizuno, T., Moal, B., Moderski, R., Mognet, I., Molinari, E., Molinaro, M., Montaruli, T., Monteiro, I., Moore, P., Moralejo Olaizola, A., Mordalska, M., Morello, C., Mori, K., Mottez, F., Moudden, Y., Moulin, E., Mrusek, I., Mukherjee, R., Munar-Adrover, P., Muraishi, H., Murase, K., Murphy, A., Nagataki, S., Naito, T., Nakajima, D., Nakamori, T., Nakayama, K., Naumann, C., Naumann, D., Naumann-Godo, M., Nayman, P., Nedbal, D., Neise, D., Nellen, L., Neustroev, V., Neyroud, N., Nicastro, L., Nicolau-Kukliński, J., Niedźwiecki, A., Niemiec, J., Nieto, D., Nikolaidis, A., Nishijima, K., Nolan, S., Northrop, R., Nosek, D., Nowak, N., Nozato, A., O'Brien, P., Ohira, Y., Ohishi, M., Ohm, S., Ohoka, H., Okuda, T., Okumura, A., Olive, J. -F., Ong, R. A., Orito, R., Orr, M., Osborne, J., Ostrowski, M., Otero, L. A., Otte, N., Ovcharov, E., Oya, I., Ozieblo, A., Padilla, L., Paiano, S., Paillot, D., Paizis, A., Palanque, S., Palatka, M., Pallota, J., Panagiotidis, K., Panazol, J. -L., Paneque, D., Panter, M., Paoletti, R., Papayannis, A., Papyan, G., Paredes, J. M., Pareschi, G., Parks, G., Parraud, J. -M., Parsons, D., Paz Arribas, M., Pech, M., Pedaletti, G., Pelassa, V., Pelat, D., Perez, M. d. C., Persic, M., Petrucci, P. -O., Peyaud, B., Pichel, A., Pita, S., Pizzolato, F., Platos, Ł., Platzer, R., Pogosyan, L., Pohl, M., Pojmanski, G., Ponz, J. D., Potter, W., Poutanen, J., Prandini, E., Prast, J., Preece, R., Profeti, F., Prokoph, H., Prouza, M., Proyetti, M., Puerto-Gimenez, I., Pühlhofer, G., Puljak, I., Punch, M., Pyzioł, R., Quel, E. J., Quinn, J., Quirrenbach, A., Racero, E., Rajda, P. J., Ramon, P., Rando, R., Rannot, R. C., Rataj, M., Raue, M., Reardon, P., Reimann, O., Reimer, A., Reimer, O., Reitberger, K., Renaud, M., Renner, S., Reville, B., Rhode, W., Ribó, M., Ribordy, M., Richer, M. G., Rico, J., Ridky, J., Rieger, F., Ringegni, P., Ripken, J., Ristori, P. R., Riviére, A., Rivoire, S., Rob, L., Roeser, U., Rohlfs, R., Rojas, G., Romano, P., Romaszkan, W., Romero, G. E., Rosen, S., Rosier Lees, S., Ross, D., Rouaix, G., Rousselle, J., Rousselle, S., Rovero, A. C., Roy, F., Royer, S., Rudak, B., Rulten, C., Rupiński, M., Russo, F., Ryde, F., Sacco, B., Saemann, E. O., Saggion, A., Sahakian, V., Saito, K., Saito, T., Saito, Y., Sakaki, N., Sakonaka, R., Salini, A., Sanchez, F., Sanchez-Conde, M., Sandoval, A., Sandaker, H., Sant'Ambrogio, E., Santangelo, A., Santos, E. M., Sanuy, A., Sapozhnikov, L., Sarkar, S., Sartore, N., Sasaki, H., Satalecka, K., Sawada, M., Scalzotto, V., Scapin, V., Scarcioffolo, M., Schafer, J., Schanz, T., Schlenstedt, S., Schlickeiser, R., Schmidt, T., Schmoll, J., Schovanek, P., Schroedter, M., Schultz, C., Schultze, J., Schulz, A., Schure, K., Schwab, T., Schwanke, U., Schwarz, J., Schwarzburg, S., Schweizer, T., Schwemmer, S., Segreto, A., Seiradakis, J. -H., Sembroski, G. H., Seweryn, K., Sharma, M., Shayduk, M., Shellard, R. C., Shi, J., Shibata, T., Shibuya, A., Shum, E., Sidoli, L., Sidz, M., Sieiro, J., Sikora, M., Silk, J., Sillanpää, A., Singh, B. B., Sitarek, J., Skole, C., Smareglia, R., Smith, A., Smith, D., Smith, J., Smith, N., Sobczyńska, D., Sol, H., Sottile, G., Sowiński, M., Spanier, F., Spiga, D., Spyrou, S., Stamatescu, V., Stamerra, A., Starling, R., Stawarz, Ł., Steenkamp, R., Stegmann, C., Steiner, S., Stergioulas, N., Sternberger, R., Sterzel, M., Stinzing, F., Stodulski, M., Straumann, U., Strazzeri, E., Stringhetti, L., Suarez, A., Suchenek, M., Sugawara, R., Sulanke, K. -H., Sun, S., Supanitsky, A. D., Suric, T., Sutcliffe, P., Sykes, J., Szanecki, M., Szepieniec, T., Szostek, A., Tagliaferri, G., Tajima, H., Takahashi, H., Takahashi, K., Takalo, L., Takami, H., Talbot, G., Tammi, J., Tanaka, M., Tanaka, S., Tasan, J., Tavani, M., Tavernet, J. -P., Tejedor, L. A., Telezhinsky, I., Temnikov, P., Tenzer, C., Terada, Y., Terrier, R., Teshima, M., Testa, V., Tezier, D., Thuermann, D., Tibaldo, L., Tibolla, O., Tiengo, A., Tluczykont, M., Todero Peixoto, C. J., Tokanai, F., Tokarz, M., Toma, K., Torii, K., Tornikoski, M., Torres, D. F., Torres, M., Tosti, G., Totani, T., Toussenel, F., Tovmassian, G., Travnicek, P., Trifoglio, M., Troyano, I., Tsinganos, K., Ueno, H., Umehara, K., Upadhya, S. S., Usher, T., Uslenghi, M., Valdes-Galicia, J. F., Vallania, P., Vallejo, G., van Driel, W., van Eldik, C., Vandenbrouke, J., Vanderwalt, J., Vankov, H., Vasileiadis, G., Vassiliev, V., Veberic, D., Vegas, I., Vercellone, S., Vergani, S., Veyssiére, C., Vialle, J. P., Viana, A., Videla, M., Vincent, P., Vincent, S., Vink, J., Vlahakis, N., Vlahos, L., Vogler, P., Vollhardt, A., von Gunten, H. -P., Vorobiov, S., Vuerli, C., Waegebaert, V., Wagner, R., Wagner, R. G., Wagner, S., Wakely, S. P., Walter, R., Walther, T., Warda, K., Warwick, R., Wawer, P., Wawrzaszek, R., Webb, N., Wegner, P., Weinstein, A., Weitzel, Q., Welsing, R., Werner, M., Wetteskind, H., White, R., Wierzcholska, A., Wiesand, S., Wilkinson, M., Williams, D. A., Willingale, R., Winiarski, K., Wischnewski, R., Wiśniewski, Ł., Wood, M., Wörnlein, A., Xiong, Q., Yadav, K. K., Yamamoto, H., Yamamoto, T., Yamazaki, R., Yanagita, S., Yebras, J. M., Yelos, D., Yoshida, A., Yoshida, T., Yoshikoshi, T., Zabalza, V., Zacharias, M., Zajczyk, A., Zanin, R., Zdziarski, A., Zech, A., Zhao, A., Zhou, X., Ziętara, K., Ziolkowski, J., Ziółkowski, P., Zitelli, V., Zurbach, C., Żychowski, P., CTA Consortium

Astroparticle Physics 43 3 - 18 2013年03月 [査読有り]

DOI

Scopus

637

被引用数

(Scopus)
DETERMINATION OF THE POINT-SPREAD FUNCTION FOR THE FERMI LARGE AREA TELESCOPE FROM ON-ORBIT DATA AND LIMITS ON PAIR HALOS OF ACTIVE GALACTIC NUCLEI

Ackermann M, Ajello M, Allafort A, Asano K, Atwood W. B, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Bloom E. D, Bonamente E, Borgland A. W, Bottacini E, Brandt T. J, Bregeon J, Brigida M, Bruel P, Buehler R, Burnett T. H, Busetto G, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chaty S, Chekhtman A, Cheung C. C, Chiang J, Cillis A. N, Ciprini S, Claus R, Cohen-Tanugi J, Colafrancesco S, Conrad J, Cutini S, D'Ammando F, de Palma F, Dermer C. D, do Couto e, Silva E, Drell S, Drlica-Wagner A, Dubois R, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Fortin P, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grandi P, Grenier I. A, Grove J. E, Guiriec S, Hadasch D, Hayashida M, Hays E, Horan D, Hou X, Hughes R. E, Jackson M. S, Jogler T, Johannesson G, Johnson R. P, Johnson A. S, Kamae T, Kataoka J, Kerr M, Knoedlseder J, Kuss M, Lande J, Larsson S, Latronico L, Lavalley C, Lee S. -H, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Mazziotta M. N, McConville W, McEnery J. E, Mehault J, Michelson P. F, Mignani R. P, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Nemmen R, Nishino S, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orienti M, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Pelassa V, Perkins J. S, Pesce-Rollins M, Pierbattista M, Piron F, Pivato G, Poon H, Porter T. A, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reyes L. C, Ritz S, Rochester L. S, Romoli C, Roth M, Sanchez D. A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Snyder A, Spandre G, Spinelli P, Stephens T. E, Suson D. J, Tajima H, Takahashi H, Tanaka T, Thayer J. G, Thayer J. B, Thompson D. J, Tibaldo L, Tibolla O, Tinivella M, Tosti G, Troja E, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, von Kienlin A, Waite A. P, Wallace E, Weltevrede P, Winer B. L, Wood K. S, Wood M, Yang Z, Zimmer S

ASTROPHYSICAL JOURNAL 765 ( 1 ) 2013年03月 [査読有り]

DOI

Scopus

68

被引用数

(Scopus)
フェルミの発見した珍種 : 電波で暗いミリ秒パルサー

谷津陽一, 河合誠之, 片岡淳, 高橋洋輔

天文月報 106 ( 4 ) 254 - 262 2013年03月

CiNii
Detection of the Characteristic Pion-Decay Signature in Supernova Remnants

Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Bellazzini R, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bottacini E, Brandt T. J, Bregeon J, Brigida M, Bruel P, Buehler R, Busetto G, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Celik O, Charles E, Chaty S, Chaves R. C. G, Chekhtman A, Cheung C. C, Chiang J, Chiaro G, Cillis A. N, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Conrad J, Corbel S, Cutini S, D'Ammando F, de Angelis A, de Palma F, Dermer C. D, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Falletti L, Favuzzi C, Ferrara E. C, Franckowiak A, Fukazawa Y, Funk S, Fusco P, Gargano F, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashida M, Hayashi K, Hays E, Hewitt J. W, Hill A. B, Hughes R. E, Jackson M. S, Jogler T, Johannesson G, Johnson A. S, Kamae T, Kataoka J, Katsuta J, Knoedlseder J, Kuss M, Lande J, Larsson S, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lovellette M. N, Lubrano P, Madejski G. M, Massaro F, Mayer M, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mignani R. P, Mitthumsiri W, Mizuno T, Moiseev A. A, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nemmen R, Nuss E, Ohno M, Ohsugi T, Omodei N, Orienti M, Orlando E, Ormes J. F, Paneque D, Perkins J. S, Pesce-Rollins M, Piron F, Pivato G, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Ritz S, Romoli C, Sanchez-Conde M, Schulz A, Sgro C, Simeon P. E, Siskind E. J, Smith D. A, Spandre G, Spinelli P, Stecker F. W, Strong A. W, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. G, Thayer J. B, Thompson D. J, Thorsett S. E, Tibaldo L, Tibolla O, Tinivella M, Troja E, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite A. P, Werner M, Winer B. L, Wood K. S, Wood M, Yamazaki R, Yang Z, Zimmer S

SCIENCE 339 ( 6121 ) 807 - 811 2013年02月 [査読有り]

DOI

Scopus

688

被引用数

(Scopus)
Development of ultra-fast ASIC for future PET scanners using TOF-capable MPPC detectors

H. Matsuda, J. Kataoka, H. Ikeda, T. Kato, T. Anbe, S. Nakamura, Y. Ishikawa, K. Sato, K. Yamamura

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 699 211 - 215 2013年01月 [査読有り]

　概要を見る

We have developed a front-end ASIC (MPPC32) intended for future PET scanners that offers time-of-flight (TOF) capability in conjunction with a multi-pixel photon counter (MPPC) array. The ASIC design is based on the open-IP project proposed by JAXA and was realized in TSMC 0.35-μm CMOS technology. The circuit comprises 32-channel, low impedance CMOS current conveyors (CCs) to effectively acquire fast MPPC signals. In order to precisely measure the coincidence timing of 511 keV gamma rays, the leading-edge method was employed instead of conventional zero-crossing measurement to discriminate signals. As a result, we obtained time jitter and walk measurement of 67 ps (FWHM) and 98 ps (within 511 keV±20%), respectively. Moreover, excellent energy resolutions of 9.8% (662 keV
FWHM) and 10.5% (511 keV
FWHM) were obtained by utilizing a 3×3 mm2 MPPC (of 50μm pitch) coupled with a Ce-doped LYSO (Ce:LYSO) crystal 3×3×10 mm3 in size. We finally report on the TOF measurements, and demonstrate that the MPPC32 developed here can be a promising device for future TOF-PET scanners using the MPPC array. © 2012 Elsevier B.V.

DOI

Scopus

13

被引用数

(Scopus)
20pSR-3 CTA報告58 : 全体報告(高エネルギーガンマ線(CTA,MAGIC),宇宙線・宇宙物理領域)

手嶋政廣, 窪秀利, 戸谷友則, 浅野勝晃, 井岡邦仁, 井川大地, 石尾一馬, 井上進, 井上芳幸, 猪目祐介, 上野遥, 大石理子, 大岡秀行, 大竹峻平, 大平豊, 荻野桃子, 奥村暁, 折戸玲子, 加賀谷美佳, 格和純, 片岡淳, 片桐英明, 株木重人, 河島孝則, 川中宣太, 岸本哲朗, 櫛田淳子, 郡司修一, 郡和範, 小島拓実, 小谷一仁, 小山志勇, 今野裕介, 齋藤浩二, 榊直人, 佐々木浩人, 澤田真理, 柴田徹, 管原隆希, 高橋慶太郎, 高橋弘充, 高橋光成, 高見一, 田島宏康, 立原研悟, 田中駿也, 田中真伸, 千川道幸, 辻本晋平, 土屋優悟, 坪根義雄, 寺島幸功, 當真賢二, 門叶冬樹, 鳥居和史, 内藤統也, 中嶋大輔, 長瀬重博, 中森健之, 中山和則, 永吉勤, 西嶋恭司, 野里明香, 野田浩司, 畑中謙一郎, 花畑義隆, 馬場浩則, 早川貴敬, 林田将明, 原敏, 馬場彩, 日高直哉, 広谷幸一, 深沢泰司, 福井康雄, 藤田裕, 増田周, 松本浩典, 水野恒史, 村石浩, 村瀬孔大, 森浩二, 柳田昭平, 山崎了, 山本常夏, 山本宏昭, 吉越貴紀, 吉田篤正, 吉田龍正, 李兆衡

日本物理学会講演概要集 68.2.1 103 2013年

DOI CiNii
Current status and optimization of handy compton camera using 3D position-sensitive scintillators

Toru Nishiyama, Jun Kataoka, Aya Kishimoto, Takuya Fujita, Kenshiro Takeuchi, Shinji Ohsuka, Sigeyuki Nakamura, Syunsuke Adachi, Michito Hirayanagi, Tetsuya Uchiyama, Yoshitaka Ishikawa, Takuya Kato

IEEE Nuclear Science Symposium Conference Record 2013年

　概要を見る

After the Japanese nuclear disaster in 2011, a large amount of radioactive isotopes was released and still remains a serious problem in Japan. To help identify radiation hotspots and ensure effective decontamination operation, we are developing a novel Compton camera weighing only 1.9 kg and measuring just 14×14×15 cm3 in size. Despite its compactness, the camera realizes a wide 180° field of vision, Δθ ∼ 10°(FWHM) angular resolution, and offers excellent sensitivity that can image a hotspot producing a 5 μSv/h dose at a distance of three meters, every 10 sec. Our key technology using 3D position-sensitive scintillators coupled with thin monolithic MPPC arrays has made this innovation possible for the first time. In this paper, we present the detailed optimization and simulation of the Compton camera currently under production with Hamamatsu Photonics. © 2013 IEEE.

DOI

Scopus

2

被引用数

(Scopus)
Gamma-ray visualization module

H. Suzuki, S. Nakamura, M. Hirayanagi, S. Adachi, T. Uchiyama, S. Ohsuka, K. Nakamoto, J. Kataoka, T. Nishiyama, T. Fujita, K. Takeuchi

IEEE Nuclear Science Symposium Conference Record 2013年

　概要を見る

Gamma ray cameras can easily locate radiation hotspots where decontamination is required. Among them, the Compton camera that utilizes the Compton scattering is compact and lightweight because no radiation shielding is required. We have developed a Compton camera for quick visualization of the radioactive contamination. It features high detection efficiency by utilizing gamma ray detectors which is a combination of Multi-Pixel Photon Counter (MPPC) array and Gadolinium Aluminum Gallium Garnet (GAGG) scintillator arrays. © 2013 IEEE.

DOI

Scopus

4

被引用数

(Scopus)
Stereo Compton cameras for the 3-D localization of radioactive isotopes optimized by Geant4

K. Takeuchi, J. Kataoka, T. Nishiyama, T. Fujita, A. Kishimoto, S. Ohsuka, S. Nakamura, A. Adachi, M. Hirayanagi, T. Uchiyama, Y. Ishikawa, T. Kato

IEEE Nuclear Science Symposium Conference Record 2013年

　概要を見る

The Compton camera is a convenient tool used to visualize the distribution of radioisotopes that emit gamma rays. Following the nuclear disaster in Fukushima in 2011, there is a particularly urgent need to develop 'gamma cameras', which can visualize the distribution of such radioisotopes. In response, we propose a portable Compton camera, which comprises 3-D position-sensitive GAGG scintillators coupled with thin monolithic MPPC arrays. We report on the detailed optimization of the detector design, based on Geant4 simulation. The results show that detection efficiency reaches up to 0.54%, or more than 10 times that of other cameras being tested in Fukushima, along with a moderate angular resolution of 8.1° (FWHM). By applying the triangular surveying method, we also propose a new concept for the 'stereo' measurement of gamma rays by using two Compton cameras, thus enabling the 3-D positional measurement of radioactive isotopes for the first time. From one point source simulation data, we ensured that the source position and the distance to the same could be determined typically to within 2 meters' accuracy and we also confirmed that more than two sources are clearly separated by the event selection from two point sources of simulation data. © 2013 IEEE.

DOI

Scopus

1

被引用数

(Scopus)
Development of the photomultiplier-tube readout system for the CTA large size telescope

H. Kubo, R. Paoletti, Y. Awane, A. Bamba, M. Barcelo, J. A. Barrio, O. Blanch, J. Boix, C. Delgado, D. Fink, D. Gascon, S. Gunji, R. Hagiwara, Y. Hanabata, K. Hatanaka, M. Hayashida, M. Ikeno, S. Kabuki, H. Katagiri, J. Kataoka, Y. Konno, S. Koyama, T. Kishimoto, J. Kushida, G. Martínez, S. Masuda, J. M. Miranda, R. Mirzoyan, T. Mizuno, T. Nagayoshi, D. Nakajima, T. Nakamori, H. Ohoka, A. Okumura, R. Orito, T. Saito, A. Sanuy, H. Sasaki, M. Sawada, T. Schweizer, R. Sugawara, K. H. Sulanke, H. Tajima, M. Tanaka, S. Tanaka, L. A. Tejedor, Y. Terada, M. Teshima, F. Tokanai, Y. Tsuchiya, T. Uchida, H. Ueno, K. Umehara, T. Yamamoto

Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013 2013-October 2013年

　概要を見る

We have developed a prototype of the photomultiplier tube (PMT) readout system for the Cherenkov Telescope Array (CTA) Large Size Telescope (LST). Two thousand PMTs along with their readout systems are arranged on the focal plane of each telescope, with one readout system per 7-PMT cluster. The Cherenkov light pulses generated by the air showers are detected by the PMTs and amplified in a compact, low noise and wide dynamic range gain block. The output of this block is then digitized at a sampling rate of the order of GHz using the Domino Ring Sampler DRS4, an analog memory ASIC developed at Paul Scherrer Institute. The sampler has 1,024 capacitors per channel and four channels are cascaded for increased depth. After a trigger is generated in the system, the charges stored in the capacitors are digitized by an external slow sampling ADC and then transmitted via Gigabit Ethernet. An onboard FPGA controls the DRS4, trigger threshold, and Ethernet transfer. In addition, the control and monitoring of the Cockcroft-Walton circuit that provides high voltage for the 7-PMT cluster are performed by the same FPGA. A prototype named Dragon has been developed that has successfully sampled PMT signals at a rate of 2 GHz, and generated single photoelectron spectra.
MAGIC and multi-wavelength observations of the radio galaxy NGC 1275

Pierre Colin, Dorit Eisenacher, Dorothée Hildebrand, Elina Lindfors, Saverio Lombardi, Kari Nilsson, Serena Partini, Fabrizio Tavecchio, Fabio Zandanel, Barabara Balmaverde, Jun Kataoka, Rami Rekola, Yosuke Takahashi

Proceedings of the 33rd International Cosmic Rays Conference, ICRC 2013 2013-October 2013年

　概要を見る

The massive radio galaxy NGC 1275 at the center of the Perseus cluster is regularly observed with the MAGIC telescopes since 2009. The observation campaign (in stereoscopic mode) between August 2010 and February 2011 leads to the first detection of the source in very high energy (VHE, >100 GeV) γ rays. NGC 1275 is one of the few non-Blazar AGNs detected in this domain which is highly dominated by BL Lac objects. The proximity and the relatively large angle between the jet axis and the line of sight allow to resolve inner-jet structures with radio interferometry and to test non-thermal emission model for larger viewing angles. NGC 1275 is then a good laboratory to locate the γ -ray emission region and understand acceleration process at work in AGNs. Here we present the long term monitoring of NGC 1275 with MAGIC as well as with Fermi-LAT (in GeV band), KVA (optical) and VLBA (15 GHz). The multiwavelength lightcurves show a correlation between γ - ray, optical and a radio component of the inner-jet. We reconstructed the broad band spectral energy distributions (SED) of the source during two separated MAGIC campaigns which both lead to the detection of NGC 1275 in VHE. We applied a one-zone Synchrotron Self Compton model with a small Doppler factor (2) which can fit the SEDs and reproduces the optical/gamma correlation. Finally, we will discuss the validity of this simple model and the implication of our results for the AGN physics.
Fermi -LAT and Suzaku observations of the radio galaxy Centaurus B

J. Katsuta, Y. T. Tanaka, L. Stawarz, S. P. O'Sullivan, C. C. Cheung, J. Kataoka, S. Funk, T. Yuasa, H. Odaka, T. Takahashi, J. Svoboda

Astronomy and Astrophysics 550 2013年

　概要を見る

Centaurus B is a nearby radio galaxy positioned in the southern hemisphere close to the Galactic plane. Here we present a detailed analysis of about 43 months of accumulated Fermi-LAT data of the γ-ray counterpart of the source initially reported in the 2nd Fermi-LAT catalog, and of newly acquired Suzaku X-ray data. We confirm its detection at GeV photon energies and analyze the extension and variability of the γ-ray source in the LAT dataset, in which it appears as a steady γ-ray emitter. The X-ray core of Centaurus B is detected as a bright source of a continuum radiation. We do not detect, however, any diffuse X-ray emission from the known radio lobes, with the provided upper limit only marginally consistent with the previously claimed ASCA flux. Two scenarios that connect the X-ray and γ-ray properties are considered. In the first one, we assume that the diffuse non-thermal X-ray emission component is not significantly below the derived Suzaku upper limit. In this case, modeling the inverse-Compton emission shows that the observed γ-ray flux of the source may in principle be produced within the lobes. This association would imply that efficient in-situ acceleration of the radiating electrons is occurring and that the lobes are dominated by the pressure from the relativistic particles. In the second scenario, with the diffuse X-ray emission well below the Suzaku upper limits, the lobes in the system are instead dominated by the magnetic pressure. In this case, the observed γ-ray flux is not likely to be produced within the lobes, but instead within the nuclear parts of the jet. By means of synchrotron self-Compton modeling, we show that this possibility could be consistent with the broad-band data collected for the unresolved core of Centaurus B, including the newly derived Suzaku spectrum. © ESO, 2013.

DOI

Scopus

17

被引用数

(Scopus)
Geometry dependence of the light collection efficiency of BGO crystal scintillators read out by avalanche photo diodes

M. Sasano, H. Nishioka, S. Okuyama, K. Nakazawa, K. Makishima, S. Yamada, T. Yuasa, A. Okumura, J. Kataoka, Y. Fukazawa, Y. Hanabata, K. Hayashi

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 715 105 - 111 2013年

　概要を見る

Abstract Light collection efficiency from BGO crystal scintillators of various sizes and shapes was measured by reading them using 1×1 cm 2 avalanche photo diodes. When the crystals have simple geometry, the light collection efficiency was found to depend on their size, shape and the read-out position through a rather well-defined empirical scaling relation. The light collection efficiency of tapered crystals was seen to depend on both the position of γ-ray irradiation, and the read-out position of the avalanche photo diodes. Using optical Monte-Carlo simulations, the relation was reproduced assuming plausible proper parameters for surface conditions and the attenuation length. This results were reproduced with a reasonable accuracy by optical Monte-Carlo simulations. Simple physical explanations are given to these geometrical effects. © 2013 Elsevier B.V.

DOI

Scopus

17

被引用数

(Scopus)
Development of signal processing system of avalanche photo diode for space observations by Astro-H

Ohno M, Goto K, Hanabata Y, Takahashi H, Fukazawa Y, Yoshino M, Saito T, Nakamori T, Kataoka J, Sasano M, Torii S, Uchiyama H, Nakazawa K, Watanabe S, Kokubun M, Ohta M, Sato T, Takahashi T, Tajima H

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 699 112 - 115 2013年 [査読有り]

DOI

Scopus

2

被引用数

(Scopus)
A novel gamma-ray detector with submillimeter resolutions using a monolithic MPPC array with pixelized Ce:LYSO and Ce:GGAG crystals

T. Kato, J. Kataoka, T. Nakamori, T. Miura, H. Matsuda, A. Kishimoto, K. Sato, Y. Ishikawa, K. Yamamura, S. Nakamura, N. Kawabata, H. Ikeda, S. Yamamoto, K. Kamada

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 699 235 - 241 2013年01月 [査読有り]

　概要を見る

We have developed a large-area monolithic Multi-Pixel Photon Counter (MPPC) array consisting of 4 x 4 channels with a three-side buttable package. Each channel has a photosensitive area of 3 x 3 mm(2) and 3600 Geiger mode avalanche photodiodes (APDs). For typical operational gain of 7.5 x 10(5) at +20 degrees C, gain fluctuation over the entire MPPC device is only +/- 5.6%, and dark count rates (as measured at the 1 p.e. level) amount to <= 400 kcps per channel. We first fabricated a gamma-ray camera consisting of the MPPC array with one-to-one coupling to a Ce-doped (Lu, Y)(2)(SiO4)O (Ce:LYSO) crystal array (4 x 4 array of 3 x 3 x 10 mm(3) crystals). Energy and time resolutions of 11.5 +/- 0.5% (FWHM at 662 keV) and 493 +/- 22 ps were obtained, respectively. When using the charge division resistor network, which compiles signals into four position-encoded analog outputs, the ultimate positional resolution is estimated as 0.19 mm in both X and Y directions, while energy resolution of 10.2 +/- 0.4% (FWHM) was obtained. Finally, we fabricated submillimeter Ce:LYSO and Ce-doped Gd3Ga3Al2O12 (Ce:GGAG) scintillator matrices each consisting of 1.0 x 1.0, 0.7 x 0.7 and 0.5 x 0.5 mm(2) pixels, to further improve the spatial resolution. In all types of Ce:LYSO and Ce:GGAG matrices, each crystal was clearly resolved in the position histograms when irradiated by a Cs-137 source. The energy resolutions for 662 keV gamma-rays for each Ce:LYSO and Ce:GGAG scintillator matrix were <= 14.3%. These results suggest excellent potential for its use as a high spatial medical imaging device, particularly in positron emission tomography (PET). (C) 2012 Elsevier B.V. All rights reserved.

DOI

Scopus

36

被引用数

(Scopus)
Development of high performance Avalanche Photodiodes and dedicated analog systems for HXI/SGD detectors onboard the Astro-H mission

T. Saito, T. Nakamori, M. Yoshino, H. Mizoma, J. Kataoka, K. Kawakami, Y. Yatsu, M. Ohno, K. Goto, Y. Hanabata, H. Takahashi, Y. Fukazawa, M. Sasano, S. Torii, H. Uchiyama, K. Nakazawa, K. Makishima, S. Watanabe, M. Kokubun, T. Takahashi, K. Mori, H. Tajima

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 699 230 - 234 2013年01月 [査読有り]

　概要を見る

Hard X-ray Imager and Soft Gamma-ray Detector are being developed as onboard instruments for the Astro-H mission, which is scheduled for launch in 2014. In both detectors, EGO scintillators play key roles in achieving high sensitivity in low Earth orbit (LEO), by generating active veto signals to reject cosmic-ray events and gamma-ray backgrounds from radio-activated detector materials. In order to maximize background rejection power, it is also important to minimize the energy threshold of this shield. As a readout sensor of weak scintillation light from a number of EGO crystals in a complicated detector system, high performance, reverse-type Avalanche Photodiodes (APDs), with an effective area of 10 x 10 mm(2) are being employed, instead of bulky photomultiplier tubes (PMTs). Another advantage of using APDs is their low power consumption, although the relatively low gain of APDs (compared to conventional PMTs) requires dedicated analog circuits for noise suppression. In this paper, we report on the development and performance of APD detectors specifically designed for the Astro-H mission. In addition to APD performance, various environmental tests, including radiation hardness and qualification thermal cycling, will be described in detail. Moreover, a dedicated charge sensitive amplifier and analog filters are newly developed and tested here to optimize the performance of APDs to activate fast veto signals within a few is from the EGO trigger. We will also report on overall performance testing of a prototype EGO detector system that mimics the data acquisition system onboard Astro-H. (C) 2012 Elsevier B.V. All rights reserved.

DOI

Scopus

10

被引用数

(Scopus)
Development of a dual-sided readout DOI-PET module using large-area monolithic mppc-arrays

Aya Kishimoto, Jun Kataoka, Takuya Kato, Takamasa Miura, Takeshi Nakamori, Kei Kamada, Shigeyuki Nakamura, Kenichi Sato, Yoshitaka Ishikawa, Kazuhisa Yamamura, Nobuyuki Kawabata, Seiichi Yamamoto

IEEE Transactions on Nuclear Science 60 ( 1 ) 38 - 43 2013年

　概要を見る

We are proposing a novel design for a module with depth of interaction (DOI) capability for gamma rays by measuring the pulse-height ratio of double-sided Multi-Pixel Photon Counters (MPPCs) coupled at both ends of a scintillation crystal block. Thanks to newly developed monolithic MPPC arrays consisting of 4 × 4 channels with a three-side buttable package, the module is very thin and compact, thereby enabling less dead space between each module when arranged into a fully designed gantry. To demonstrate our concept of a DOI measuring technique, we first made a 1-D crystal array consisting of five Ce-doped Gd3Al2Ga3O12 (Ce:GAGG) cubic crystals measuring 3× 3× 3\\mm3 in size, separated by a layer of air approximately 10 μ m-thick. When the light signals output from both ends are read with the 3× 3 mm2 MPPCs, the position of each crystal is clearly distinguished. The same measurements were also made using Ce-doped (Lu,Y)2(SiO4)O(Ce:LYSO), achieving a similarly good separation. We then fabricated thin Ce:GAGG 2-D crystal arrays consisting of two types: [A] 4 × 4 matrix of 3× 3× 3mm} 3 pixels, and [B] 10 × 10 matrix of 0.8× 0.8× 5 mm3 pixels, with each pixel divided by a BaSO4 reflector 0.2 mm-thick. Then four arrays are laid on top of each other facing the DOI direction through a layer of air 10 μm-thick. We demonstrated that the 3-D position of each Ce:GAGG pixel is clearly distinguished in both the 2-D and DOI directions for type A and B when illuminated by 662 keV gamma rays. Average energy resolutions of 9.8 ± 0.8% and 11.8 ± 1.3% were obtained for types A and B, respectively. These results suggest that our proposed method is simple and offers promise in achieving both excellent spatial and energy resolutions for future medical imaging, particularly in positron emission tomography (PET). © 1963-2012 IEEE.

DOI

Scopus

70

被引用数

(Scopus)
Development of a dual-sided readout DOI-PET module using large-area monolithic mppc-arrays

Aya Kishimoto, Jun Kataoka, Takuya Kato, Takamasa Miura, Takeshi Nakamori, Kei Kamada, Shigeyuki Nakamura, Kenichi Sato, Yoshitaka Ishikawa, Kazuhisa Yamamura, Nobuyuki Kawabata, Seiichi Yamamoto

IEEE Transactions on Nuclear Science 60 ( 1 ) 38 - 43 2013年

　概要を見る

We are proposing a novel design for a module with depth of interaction (DOI) capability for gamma rays by measuring the pulse-height ratio of double-sided Multi-Pixel Photon Counters (MPPCs) coupled at both ends of a scintillation crystal block. Thanks to newly developed monolithic MPPC arrays consisting of 4 × 4 channels with a three-side buttable package, the module is very thin and compact, thereby enabling less dead space between each module when arranged into a fully designed gantry. To demonstrate our concept of a DOI measuring technique, we first made a 1-D crystal array consisting of five Ce-doped Gd3Al2Ga3O12 (Ce:GAGG) cubic crystals measuring 3× 3× 3\\mm3 in size, separated by a layer of air approximately 10 μ m-thick. When the light signals output from both ends are read with the 3× 3 mm2 MPPCs, the position of each crystal is clearly distinguished. The same measurements were also made using Ce-doped (Lu,Y)2(SiO4)O(Ce:LYSO), achieving a similarly good separation. We then fabricated thin Ce:GAGG 2-D crystal arrays consisting of two types: [A] 4 × 4 matrix of 3× 3× 3mm} 3 pixels, and [B] 10 × 10 matrix of 0.8× 0.8× 5 mm3 pixels, with each pixel divided by a BaSO4 reflector 0.2 mm-thick. Then four arrays are laid on top of each other facing the DOI direction through a layer of air 10 μm-thick. We demonstrated that the 3-D position of each Ce:GAGG pixel is clearly distinguished in both the 2-D and DOI directions for type A and B when illuminated by 662 keV gamma rays. Average energy resolutions of 9.8 ± 0.8% and 11.8 ± 1.3% were obtained for types A and B, respectively. These results suggest that our proposed method is simple and offers promise in achieving both excellent spatial and energy resolutions for future medical imaging, particularly in positron emission tomography (PET). © 1963-2012 IEEE.

DOI

Scopus

70

被引用数

(Scopus)
Binary Millisecond Pulsar Discovery via Gamma-Ray Pulsations

Pletsch H. J, Guillemot L, Fehrmann H, Allen B, Kramer M, Aulbert C, Ackermann M, Ajello M, de Angelis A, Atwood W. B, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Borgland A. W, Bottacini E, Brandt T. J, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Charles E, Chaves R. C. G, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, D'Ammando F, Dermer C. D, Digel S. W, Drell P. S, Drlica-Wagner A, Dubois R, Dumora D, Favuzzi C, Ferrara E. C, Franckowiak A, Fukazawa Y, Fusco P, Gargano F, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, den Hartog P. R, Hayashida M, Hays E, Hill A. B, Hou X, Hughes R. E, Johannesson G, Jackson M. S, Jogler T, Johnson A. S, Johnson W. N, Kataoka J, Kerr M, Knoedlseder J, Kuss M, Lande J, Larsson S, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lovellette M. N, Lubrano P, Massaro F, Mayer M, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mitthumsiri W, Mizuno T, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nemmen R, Nuss E, Ohno M, Ohsugi T, Omodei N, Orienti M, Orlando E, de Palma F, Paneque D, Perkins J. S, Piron F, Pivato G, Porter T. A, Raino S, Rando R, Ray P. S, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Romani R. W, Romoli C, Sanchez D. A, Parkinson P, M. Saz, Schulz A, Sgro C, do Couto e, Silva E, Siskind E. J, Smith D. A, Spandre G, Spinelli P, Suson D. J, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Tinivella M, Troja E, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite A. P, Winer B. L, Wood K. S, Wood M, Yang Z, Zimmer S

SCIENCE 338 ( 6112 ) 1314 - 1317 2012年12月 [査読有り]

DOI

Scopus

101

被引用数

(Scopus)
The Imprint of the Extragalactic Background Light in the Gamma-Ray Spectra of Blazars

Ackermann M, Ajello M, Allafort A, Schady P, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bellazzini R, Blandford R. D, Bloom E. D, Borgland A. W, Bottacini E, Bouvier A, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Cavazzuti E, Cecchi C, Charles E, Chaves R. C. G, Chekhtman A, Cheung C. C, Chiang J, Chiaro G, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, D'Ammando F, de Palma F, Dermer C. D, Digel S. W, do Couto e, Silva E, Domnguez A, Drell P. S, Drlica-Wagner A, Favuzzi C, Fegan S. J, Focke W. B, Franckowiak A, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grove J. E, Guiriec S, Gustafsson M, Hadasch D, Hayashida M, Hays E, Jackson M. S, Jogler T, Kataoka J, Knoedlseder J, Kuss M, Lande J, Larsson S, Latronico L, Longo F, Loparco F, Lovellette M. N, Lubrano P, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Tramacere A, Nuss E, Greiner J, Ohno M, Ohsugi T, Omodei N, Orienti M, Orlando E, Ormes J. F, Paneque D, Perkins J. S, Pesce-Rollins M, Piron F, Pivato G, Porter T. A, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reyes L. C, Ritz S., Rau A, Romoli C, Roth M, Sanchez-Conde M, Sanchez D. A, Scargle J. D, Sgro C, Siskind E. J, Spandre G, Spinelli P, Stawarz Lukasz, Suson D. J, Takahashi H, Tanaka T, Thayer J. G, Thompson D. J, Tibaldo L, Tinivella M, Torres D. F, Tosti G, Troja E, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite A. P, Winer B. L, Wood K. S, Wood M

SCIENCE 338 ( 6111 ) 1190 - 1192 2012年11月 [査読有り]

DOI

Scopus

236

被引用数

(Scopus)
The fermi large area telescope on orbit: Event classification, instrument response functions, and calibration

M. Ackermann, M. Ajello, A. Albert, A. Allafort, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, E. Bissaldi, R. D. Blandford, E. D. Bloom, J. R. Bogart, E. Bonamente, A. W. Borgland, E. Bottacini, A. Bouvier, T. J. Brandt, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, Ö Çelik, E. Charles, R. C.G. Chaves, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, R. Corbet, S. Cutini, F. D'Ammando, D. S. Davis, A. De Angelis, M. Deklotz, F. De Palma, C. D. Dermer, S. W. Digel, E. Do Couto E Silva, P. S. Drell, A. Drlica-Wagner, R. Dubois, C. Favuzzi, S. J. Fegan, E. C. Ferrara, W. B. Focke, P. Fortin, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, B. Giebels, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, J. E. Grove, S. Guiriec, D. Hadasch, M. Hayashida, E. Hays, D. Horan, X. Hou, R. E. Hughes, M. S. Jackson, T. Jogler, G. Jóhannesson, R. P. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knödlseder, M. Kuss, J. Lande, S. Larsson, L. Latronico, C. Lavalley, M. Lemoine-Goumard, F. Longo

Astrophysical Journal, Supplement Series 203 ( 1 ) 2012年11月

　概要を見る

The Fermi Large Area Telescope (Fermi-LAT, hereafter LAT), the primary instrument on the Fermi Gamma-ray Space Telescope (Fermi) mission, is an imaging, wide field-of-view, high-energy γ-ray telescope, covering the energy range from 20MeV to more than 300GeV. During the first years of the mission, the LAT team has gained considerable insight into the in-flight performance of the instrument. Accordingly, we have updated the analysis used to reduce LAT data for public release as well as the instrument response functions (IRFs), the description of the instrument performance provided for data analysis. In this paper, we describe the effects that motivated these updates. Furthermore, we discuss how we originally derived IRFs from Monte Carlo simulations and later corrected those IRFs for discrepancies observed between flight and simulated data. We also give details of the validations performed using flight data and quantify the residual uncertainties in the IRFs. Finally, we describe techniques the LAT team has developed to propagate those uncertainties into estimates of the systematic errors on common measurements such as fluxes and spectra of astrophysical sources. © 2012 The American Astronomical Society. All rights reserved.

DOI

Scopus

451

被引用数

(Scopus)
Development of a MPPC-based DOI-PET module with submillimeter 3-D resolution

Kishimoto, A, Kataoka, J, Kato, T, Miura, T, Nakamori, T, Kamada, K, Nakamura, S, Sato, K, Ishikawa, Y, Ymamura, K, Yamamoto, S

2012 IEEE NSS/MIC Conference Record 3128 - 3133 2012年10月

DOI

Scopus

4

被引用数

(Scopus)
High position resolution gamma-ray imagers consisting of a monolithic MPPC array with submillimeter pixelized scintillator crystals

Kato, T, Kataoka, J, Nakamori, T, Kishimoto, A, Yamamoto, S, Sato, K, Ishikawa, Y, Yamamura, K, Nakamura, S, Kawabata, N, Ikeda, H, Kamada, K

2012 IEEE NSS/MIC Conference Record 3146 - 3152 2012年10月

DOI

Scopus

4

被引用数

(Scopus)
FERMI OBSERVATIONS OF gamma-RAY EMISSION FROM THE MOON

Abdo A. A, Ackermann M, Ajello M, Atwoo W. B, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bonamente E, Borgland A. W, Bottacini E, Bouvier A, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, D'Ammando F, de Angelis A, de Palma F, Dermer C. D, Digel S. W, Silva E. do Couto E, Drell P. S, Drlica-Wagner A, Dubois R, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Fukazawa Y, Funk S, Fusco P, Gargano F, Gehrels N, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Gomez-Vargas G. A, Grenier I. A, Grove J. E, Guiriec S, Hadasch D, Hays E, Hill A. B, Horan D, Hou X, Hughes R. E, Iafrate G, Jackson M. S, Johannesson G, Johnson A. S, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Larsson S, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Okumura A, Omodei N, Orienti M, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pesce-Rollins M, Pierbattista M, Piron F, Pivato G, Poon H, Porter T. A, Prokhorov D, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reposeur T, Rochester L. S, Roth M, Sadrozinski H. F. -W, Sanchez D. A, Sbarra C, Schalk T. L, Sgro C, Share G. H, Siskind E. J, Spandre G, Spinelli P, Stawarz L, Takahashi H, Tanaka T, Thayer J. G, Thayer J. B, Thompson D. J, Tibaldo L, Tinivella M, Torres D. F, Tosti G, Troja E, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite A. P, Wang P, Winer B. L, Wood D. L, Wood K. S, Yang Z, Zimmer S

ASTROPHYSICAL JOURNAL 758 ( 2 ) 2012年10月 [査読有り]

DOI

Scopus

24

被引用数

(Scopus)
未同定ガンマ線天体1FGL J1311.7-3429 のX線・可視光観測

J.Kataoka

The Astrophysical Journal 757 ( 2 ) 176 - 184 2012年10月 [査読有り]

DOI

Scopus

26

被引用数

(Scopus)
TOWARD IDENTIFYING THE UNASSOCIATED GAMMA-RAY SOURCE 1FGL J1311.7-3429 WITH X-RAY AND OPTICAL OBSERVATIONS

J. Kataoka, Y. Yatsu, N. Kawai, Y. Urata, C. C. Cheung, Y. Takahashi, K. Maeda, T. Totani, R. Makiya, H. Hanayama, T. Miyaji, A. Tsai

ASTROPHYSICAL JOURNAL 757 ( 2 ) 2012年10月

　概要を見る

We present deep optical and X-ray follow-up observations of the bright unassociated Fermi-LAT gamma-ray source 1FGL J1311.7-3429. The source was already known as an unidentified EGRET source (3EG J1314-3431, EGR J1314-3417), hence its nature has remained uncertain for the past two decades. For the putative counterpart, we detected a quasi-sinusoidal optical modulation of Delta m similar to 2 mag with a period of similar or equal to 1.5 hr in the Rc, r', and g' bands. Moreover, we found that the amplitude of the modulation and peak intensity changed by greater than or similar to 1 mag and similar to 0.5 mag, respectively, over our total six nights of observations from 2012 March to May. Combined with Swift UVOT data, the optical-UV spectrum is consistent with a blackbody temperature, kT similar or equal to 1 eV and the emission volume radius R-bb similar or equal to 1.5 x 10(4) d(kpc) km (d(kpc) is the distance to the source in units of 1 kpc). In contrast, deep Suzaku observations conducted in 2009 and 2011 revealed strong X-ray flares with a light curve characterized with a power spectrum density of P(f) proportional to f(-2.0 +/- 0.4), but the folded X-ray light curves suggest an orbital modulation also in X-rays. Together with the non-detection of a radio counterpart, and significant curved spectrum and non-detection of variability in gamma-rays, the source may be the second "radio-quiet" gamma-ray emitting millisecond pulsar candidate after 1FGL J2339.7-0531, although the origin of flaring X-ray and optical variability remains an open question.

DOI

Scopus

26

被引用数

(Scopus)
GAMMA-RAY OBSERVATIONS OF THE ORION MOLECULAR CLOUDS WITH THE FERMI LARGE AREA TELESCOPE

Ackermann M, Ajello M, Allafort A, Antolini E, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bottacini E, Brandt T. J, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Cecchi C, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, D'Ammando F, de Angelis A, de Palma F, Dermer C. D, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Enoto T, Falletti L, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Fukazawa Y, Fukui Y, Fusco P, Gargano F, Gasparrini D, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashida M, Hayashi K, Horan D, Hou X, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Kamae T, Katagiri H, Kataoka J, Kerr M, Knodlseder J, Kuss M, Lande J, Larsson S, Lee S. -H, Longo F, Loparco F, Lovellette M. N, Lubrano P, Makishima K, Mazziotta M. N, Mehault J, Mitthumsiri W, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nishino S, Norris J. P, Nuss E, Ohno M, Ohsugi T, Okumura A, Orienti M, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pesce-Rollins M, Pierbattista M, Piron F, Pivato G, Porter T. A, Raino S, Razzano M, Reimer A, Reimer O, Roth M, Sadrozinski H. F. -W, Sgro C, Siskind E. J, Spandre G, Spinelli P, Strong A. W, Takahashi H, Takahashi T, Tanaka T, Thayer J. G, Thayer J. B, Tibolla O, Tinivella M, Torres D. F, Tramacere A, Troja E, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yang Z, Zimmer S

ASTROPHYSICAL JOURNAL 756 ( 1 ) 2012年09月 [査読有り]

DOI

Scopus

39

被引用数

(Scopus)
Development of a micro-satellite TSUBAME for X-ray polarimetry of GRBs

Yatsu, Y, Hayashi, M, Kawakami, K, Tokoyoda, K, Enomoto, T, Toizumi, T, Kawai, N, Ishizaka, K, Muta, A, Morishita, H, Matsunaga, S, Nakamori, T, Kataoka, J, Kubo, S

Proceedings of the International Astronomical Union 279 ( S279 ) 423 - 424 2012年09月

DOI

Scopus

2

被引用数

(Scopus)
GeV OBSERVATIONS OF STAR-FORMING GALAXIES WITH THE FERMI LARGE AREA TELESCOPE

Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chekhtman A, Cheung C. C, Chiang J, Cillis A. N, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, de Palma F, Dermer C. D, Digel S. W, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Favuzzi C, Fegan S. J, Fortin P, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Germani S, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Guiriec S, Gustafsson M, Hadasch D, Hayashida M, Hays E, Hughes R. E, Johannesson G, Johnson A. S, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Martin P, Mazziotta M. N, McEnery J. E, Michelson P. F, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nishino S, Norris J. P, Nuss E, Ohno M, Ohsugi T, Okumura A, Omodei N, Orlando E, Ozaki M, Parent D, Persic M, Pesce-Rollins M, Petrosian V, Pierbattista M, Piron F, Pivato G, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Ritz S, Roth M, Sbarra C, Sgro C, Siskind E. J, Spandre G, Spinelli P, Stawarz Lukasz, Strong A. W, Takahashi H, Tanaka T, Thayer J. B, Tibaldo L, Tinivella M, Torres D. F, Tosti G, Troja E, Uchiyama Y, Vandenbroucke J, Vianello G, Vitale V, Waite A. P, Wood M, Yang Z

ASTROPHYSICAL JOURNAL 755 ( 2 ) 2012年08月 [査読有り]

DOI

Scopus

344

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE STUDY OF COSMIC RAYS AND THE INTERSTELLAR MEDIUM IN NEARBY MOLECULAR CLOUDS

Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bottacini E, Brandt T. J, Bregeon J, Brigida M, Bruel P, Buehler R, Busetto G, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, D'Ammando F, de Angelis A, de Palma F, Dermer C. D, Digel S. W, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Falletti L, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Fukazawa Y, Fukui Y, Funk S, Fusco P, Gargano F, Gasparrini D, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashi K, Horan D, Hou X, Hughes R. E, Itoh R, Jackson M. S, Johannesson G, Johnson A. S, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Larsson S, Lee S. -H, Lemoine-Goumard M, Longo F, Loparco F, Lovellette M. N, Lubrano P, Martin P, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Nemmen R, Nishino S, Norris J. P, Nuss E, Ohno M, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pesce-Rollins M, Pierbattista M, Piron F, Pivato G, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Romoli C, Roth M, Sada T, Sadrozinski H. F. -W, Sanchez D. A, Sbarra C, Sgro C, Siskind E. J, Spandre G, Spinelli P, Strong A. W, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. G, Thayer J. B, Thompson D. J, Tibaldo L, Tibolla O, Tinivella M, Torres D. F, Tosti G, Tramacere A, Troja E, Uchiyama Y, Uehara T, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yamamoto H, Yang Z, Zimmer S

ASTROPHYSICAL JOURNAL 755 ( 1 ) 2012年08月 [査読有り]

DOI

Scopus

55

被引用数

(Scopus)
CONSTRAINING THE HIGH-ENERGY EMISSION FROM GAMMA-RAY BURSTS WITH FERMI

ASTROPHYSICAL JOURNAL 754 ( 2 ) 2012年08月 [査読有り]

DOI

Scopus

66

被引用数

(Scopus)
Large size single crystal growth of Lu3Al5O12:Pr and their uniformity of scintillation properties

Kei Kamada, Takayuki Yanagida, Takanori Endo, Kousuke Tsutumi, Masao Yoshino, Jun Kataoka, Yoshiyuki Usuki, Yutaka Fujimoto, Akihiro Fukabori, Akira Yoshikawa

JOURNAL OF CRYSTAL GROWTH 352 ( 1 ) 91 - 94 2012年08月 [査読有り]

　概要を見る

Pr-doped Lu3Al5O12 (Pr:LuAG) single crystals were grown by the Czochralski method. The crystal was seeded-grown in the [100] direction. Dimensions up to 100 mm in length and 92 mm in diameter were achieved without cracking. Using 10 x 10 x 10 mm size sample coupled with photomultiplier (Hamamatsu R3998), energy resolution of 4.6% at 662 keV was achieved. Uniformity of light yield and energy resolution was also evaluated in whole crystal. The deviations of light output, energy resolution, and decay time were +/- 7.9%, 7.2%, and 4.8%, respectively. (C) 2011 Elsevier B.V. All rights reserved.

DOI

Scopus

31

被引用数

(Scopus)
A STATISTICAL APPROACH TO RECOGNIZING SOURCE CLASSES FOR UNASSOCIATED SOURCES IN THE FIRST FERMI-LAT CATALOG

Ackermann M, Ajello M, Allafort A, Antolini E, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Br, dt T. J, Bregeon J, Brigida M, Bruel P, Buehler R, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cavazzuti E, Cecchi C, Celik O, Charles E, Chekhtman A, Chen A. W, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, de Angelis A, DeCesar M. E, De Luca A, de Palma F, Dermer C. D, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Dubois R, Enoto T, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Fortin P, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Gustafsson M, Hadasch D, Hanabata Y, Harding A. K, Hayashida M, Hays E, Healey S. E, Hill A. B, Horan D, Hou X, Johannesson G, Johnson A. S, Johnson T. J, Kamae T, Katagiri H, Kataoka J, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mignani R. P, Mitthumsiri W, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pesce-Rollins M, Pierbattista M, Piron F, Pivato G, Porter T. A, Raino S, Rando R, Ray P. S, Razzano M, Reimer A, Reimer O, Reposeur T, Romani R. W, Sadrozinski H. F. -W, Salvetti D, Parkinson P, M. Saz, Schalk T. L, Sgro C, Shaw M. S, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Suson D. J, Takahashi H, Tanaka T, Thayer J. G, Thayer J. B, Thompson D. J, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Troja E, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vilchez N, Vitale V, Waite A. P, Wallace E, Wang P, Winer B. L, Wolff M. T, Wood D. L, Wood K. S, Yang Z, Zimmer S

ASTROPHYSICAL JOURNAL 753 ( 1 ) 2012年07月 [査読有り]

DOI

Scopus

108

被引用数

(Scopus)
VLBI and single-dish monitoring of 3C 84 for the period 2009-2011

H. Nagai, M. Orienti, M. Kino, K. Suzuki, G. Giovannini, A. Doi, K. Asada, M. Giroletti, J. Kataoka, F. D'Ammando, M. Inoue, A. Lähteenmäki, M. Tornikoski, J. Léon-Tavares, S. Kameno, U. Bach

Monthly Notices of the Royal Astronomical Society: Letters 423 ( 1 ) 2012年06月

　概要を見る

The radio galaxy 3C 84 is a representative of γ -ray-bright misaligned active galactic nuclei (AGNs) and one of the best laboratories to study the radio properties of the subparsec jet in connection with the γ -ray emission. In order to identify possible radio counterparts of γ -ray emissions in 3C 84, we study the change in structure within the central 1 pc and the light curve of subparsec-sized components C1, C2 and C3. We search for any correlation between changes in the radio components and the γ -ray flares by making use of the Very Long Baseline Interferometry (VLBI) and single-dish data. Throughout the radio monitoring spanning over two GeV γ -ray flares detected by the Fermi Large Area Telescope and theMAGIC Cherenkov Telescope during 2009 April-May and 2010 June-August, the total flux density in the radio band increases on average. This flux increase mostly originates in C3. Although γ -ray flares span the time-scale of days to weeks, no clear correlation with the radio light curve on this time-scale is found. No new prominent components and change in morphology associated with the γ -ray flares are found on VLBI images. © 2012 The Authors. Monthly Notices of the Royal Astronomical Society. © 2012 RAS.

DOI

Scopus

33

被引用数

(Scopus)
MULTI-WAVELENGTH OBSERVATIONS OF BLAZAR AO 0235+164 IN THE 2008-2009 FLARING STATE

ASTROPHYSICAL JOURNAL 751 ( 2 ) 2012年06月 [査読有り]

DOI

Scopus

56

被引用数

(Scopus)
Expected radiation damage of reverse-type APDs for the Astro-H mission

J. Kataoka, T. Saito, M. Yoshino, H. Mizoma, T. Nakamori, Y. Yatsu, Y. Ishikawa, Y. Matsunaga, H. Tajima, M. Kokubun, P. G. Edwards

JOURNAL OF INSTRUMENTATION 7 ( 6 ) 2012年06月 [査読有り]

　概要を見る

Scheduled for launch in 2014, Astro-H is the sixth Japanese X-ray astronomy satellite mission. More than 60 silicon avalanche photodiodes (Si-APDs; hereafter APDs) will be used to read out BGO scintillators, which are implemented to generate a veto signal to reduce background contamination for the hard X-ray imager (HXI) and a soft gamma-ray detector (SGD). To date, however, APDs have rarely been used in space experiments. Moreover, strict environmental tests are necessary to guarantee APD performance for missions expected to extend beyond five years. The radiation hardness of APDs, as for most semiconductors, is particularly crucial, since radiation in the space environment is severe. In this paper, we present the results of radiation tests conducted on reverse-type APDs (provided by Hamamatsu Photonics) irradiated by gamma rays (Co-60) and 150 MeV protons. We show that, even under the same 100 Gy dose, high energy protons can cause displacement (bulk) damage in the depletion region and possibly change the activation energy, whereas gamma-ray irradiation is less prone to cause damage, because ionization damage dominates only the surface region. We also present quantitative guidance on how to estimate APD noise deterioration over a range of temperatures and radiation doses. As a practical example, we discuss the expected degradation of the BGO energy threshold for the generation of veto signals, following several years of Astro-H operation in Low Earth Orbit (LEO), and directly compare it to experimental results obtained using a small BGO crystal.

DOI

Scopus

9

被引用数

(Scopus)
Astro-H衛星搭載のAPD検出器の放射線耐性

J.Kataoka

Journal of Instrumentation 7 ( 6 ) 2012年06月 [査読有り]

DOI

Scopus

9

被引用数

(Scopus)
Discovery of the millisecond pulsar PSR J2043+1711 in a Fermi source with the Nançay Radio Telescope

L. Guillemot, P. C.C. Freire, I. Cognard, T. J. Johnson, Y. Takahashi, J. Kataoka, G. Desvignes, F. Camilo, E. C. Ferrara, A. K. Harding, G. H. Janssen, M. Keith, M. Kerr, M. Kramer, D. Parent, S. M. Ransom, P. S. Ray, P. M. Saz Parkinson, D. A. Smith, B. W. Stappers, G. Theureau

Monthly Notices of the Royal Astronomical Society 422 ( 2 ) 1294 - 1305 2012年05月

　概要を見る

We report the discovery of the millisecond pulsar PSR J2043+1711 in a search of a Fermi Large Area Telescope (LAT) source with no known associations, with the Nançay Radio Telescope. The new pulsar, confirmed with the Green Bank Telescope, has a spin period of 2.38ms, is relatively nearby (kpc) and is in a 1.48-d orbit around a low-mass companion, probably an He-type white dwarf. Using an ephemeris based on Arecibo, Nançay and Westerbork timing measurements, pulsed gamma-ray emission was detected in the data recorded by the Fermi LAT. The gamma-ray light curve and spectral properties are typical of other gamma-ray millisecond pulsars seen with Fermi. X-ray observations of the pulsar with Suzaku and the Swift X-ray Telescope yielded no detection. At 1.4GHz, we observe strong flux density variations because of interstellar diffractive scintillation; however, a sharp peak can be observed at this frequency during bright scintillation states. At 327MHz, the pulsar is detected with a much higher signal-to-noise ratio and its flux density is far more steady. However, at that frequency the Arecibo instrumentation cannot yet fully resolve the pulse profile. Despite that, our pulse time-of-arrival measurements have a post-fit residual rms of 2s. This and the expected stability of this system have made PSR J2043+1711 one of the first new Fermi-selected millisecond pulsars to be added to pulsar gravitational wave timing arrays. It has also allowed a significant measurement of relativistic delays in the times of arrival of the pulses due to the curvature of space-time near the companion, but not yet with enough precision to derive useful masses for the pulsar and the companion. Nevertheless, a mass for the pulsar between 1.7 and 2.0M ⊙ can be derived if a standard millisecond pulsar formation model is assumed. In this paper, we also present a comprehensive summary of pulsar searches in Fermi LAT sources with the Nançay Radio Telescope to date. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS.

DOI

Scopus

43

被引用数

(Scopus)
FERMI-LAT OBSERVATIONS OF THE DIFFUSE gamma-RAY EMISSION: IMPLICATIONS FORCOSMIC RAYS AND THE INTERSTELLAR MEDIUM

Ackermann M, Ajello M, Atwood W. B, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgla, A. W, Brandt T. J, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Cavazzuti E, Cecchi C, Charles E, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, de Angelis A, de Palma F, Dermer C. D, Digel S. W, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Falletti L, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Fortin P, Fukazawa Y, Funk S, Fusco P, Gaggero D, Gargano F, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grove J. E, Guiriec S, Gustafsson M, Hadasch D, Hanabata Y, Harding A. K, Hayashida M, Hays E, Horan D, Hou X, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Mazziotta M. N, McEnery J. E, Michelson P. F, Mitthumsiri W, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Parent D, Pesce-Rollins M, Pierbattista M, Piron F, Pivato G, Porter T. A, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Sadrozinski H. F. -W, Sgro C, Siskind E. J, Spandre G, Spinelli P, Strong A. W, Suson D. J, Takahashi H, Tanaka T, Thayer J. G, Thayer J. B, Thompson D. J, Tibaldo L, Tinivella M, Torres D. F, Tosti G, Troja E, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Wood M, Yang Z, Ziegler M, Zimmer S

ASTROPHYSICAL JOURNAL 750 ( 1 ) 2012年05月 [査読有り]

DOI

Scopus

628

被引用数

(Scopus)
Fermi large area telescope second source catalog

P. L. Nolan, A. A. Abdo, M. Ackermann, M. Ajello, A. Allafort, E. Antolini, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, A. Belfiore, R. Bellazzini, B. Berenji, G. F. Bignami, R. D. Blandford, E. D. Bloom, E. Bonamente, J. Bonnell, A. W. Borgland, E. Bottacini, A. Bouvier, T. J. Brandt, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, R. Campana, B. Cañadas, A. Cannon, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, M. Ceccanti, C. Cecchi, Ö Çelik, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, R. Chipaux, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, R. Corbet, S. Cutini, F. D'Ammando, D. S. Davis, A. De Angelis, M. E. Decesar, M. Deklotz, A. De Luca, P. R. Den Hartog, F. De Palma, C. D. Dermer, S. W. Digel, E. Do Couto E Silva, P. S. Drell, A. Drlica-Wagner, R. Dubois, D. Dumora, T. Enoto, L. Escande, D. Fabiani, L. Falletti, C. Favuzzi, S. J. Fegan, E. C. Ferrara, W. B. Focke, P. Fortin, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, M. Gustafsson, D. Hadasch

Astrophysical Journal, Supplement Series 199 ( 2 ) 2012年04月

　概要を見る

We present the second catalog of high-energy γ-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), derived from data taken during the first 24months of the science phase of the mission, which began on 2008 August 4. Source detection is based on the average flux over the 24month period. The second Fermi-LAT catalog (2FGL) includes source location regions, defined in terms of elliptical fits to the 95% confidence regions and spectral fits in terms of power-law, exponentially cutoff power-law, or log-normal forms. Also included are flux measurements in five energy bands and light curves on monthly intervals for each source. Twelve sources in the catalog are modeled as spatially extended. We provide a detailed comparison of the results from this catalog with those from the first Fermi-LAT catalog (1FGL). Although the diffuse Galactic and isotropic models used in the 2FGL analysis are improved compared to the 1FGL catalog, we attach caution flags to 162 of the sources to indicate possible confusion with residual imperfections in the diffuse model. The 2FGL catalog contains 1873 sources detected and characterized in the 100MeV to 100GeV range of which we consider 127 as being firmly identified and 1171 as being reliably associated with counterparts of known or likely γ-ray-producing source classes. © 2012 The American Astronomical Society. All rights reserved.

DOI

Scopus

1205

被引用数

(Scopus)
SUZAKU X-RAY IMAGING OF THE EXTENDED LOBE IN THE GIANT RADIO GALAXY NGC 6251 ASSOCIATED WITH THE FERMI-LAT SOURCE 2FGL J1629.4+8236

Y. Takeuchi, J. Kataoka, L. Stawarz, Y. Takahashi, K. Maeda, T. Nakamori, C. C. Cheung, A. Celotti, Y. Tanaka, T. Takahashi

ASTROPHYSICAL JOURNAL 749 ( 1 ) 66 2012年04月 [査読有り]

　概要を見る

We report the results of a Suzaku X-ray imaging study of NGC 6251, a nearby giant radio galaxy with intermediate FR I/II radio properties. Our pointing direction was centered on the gamma-ray emission peak recently discovered with the Fermi Large Area Telescope (LAT) around the position of the northwest (NW) radio lobe 15 arcmin offset from the nucleus. After subtracting two "off-source" pointings adjacent to the radio lobe and removing possible contaminants in the X-ray Imaging Spectrometer field of view, we found significant residual X-ray emission most likely diffuse in nature. The spectrum of the excess X-ray emission is well fitted by a power law with a photon index Gamma = 1.90 +/- 0.15 and a 0.5-8 keV flux of 4x10(-13) erg cm(-2) s(-1). We interpret this diffuse X-ray emission component as being due to inverse Compton upscattering of the cosmic microwave background photons by ultrarelativistic electrons within the lobe, with only a minor contribution from the beamed emission of the large-scale jet. Utilizing archival radio data for the source, we demonstrate by means of broadband spectral modeling that the gamma-ray flux of the Fermi-LAT source 2FGL J1629.4+8236 may well be accounted for by the high-energy tail of the inverse Compton continuum of the lobe. Thus, this claimed association of gamma-rays from the NW lobe of NGC 6251, together with the recent Fermi-LAT imaging of the extended lobes of Centaurus A, indicates that particles may be efficiently (re-)accelerated up to ultrarelativistic energies within extended radio lobes of nearby radio galaxies in general.

DOI

Scopus

21

被引用数

(Scopus)
Development of X-ray/gamma-ray imaging spectrometers using reach-through APD arrays

Nakamori, T, Enomoto, T, Toizumi, T, Tokoyoda, K, Yatsu, Y, Kawai, N, Kataoka, J, Ishikawa, Y, Kawai, T, Kawabata, N, Matsunaga, Y

Journal of Instrumentaion 7 ( 3 ) C03038 - 10pp 2012年03月 [査読有り]

DOI

Scopus

1

被引用数

(Scopus)
SEARCH FOR GAMMA-RAY EMISSION FROM X-RAY-SELECTED SEYFERT GALAXIES WITH FERMI-LAT

Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cavazzuti E, Cecchi C, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, D'Ammando F, de Angelis A, de Palma F, Dermer C. D, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Enoto T, Favuzzi C, Fegan S. J, Ferrara E. C, Fortin P, Fukazawa Y, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Godfrey G, Grove J. E, Guiriec S, Hadasch D, Hayashida M, Hays E, Hughes R. E, Johannesson G, Johnson A. S, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Mazziotta M. N, Michelson P. F, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nishino S, Norris J. P, Nuss E, Ohno M, Ohsugi T, Okumura A, Orlando E, Ozaki M, Paneque D, Pesce-Rollins M, Pierbattista M, Piron F, Pivato G, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Ritz S, Roth M, Sanchez D. A, Sbarra C, Sgro C, Siskind E. J, Spandre G, Spinelli P, Stawarz L, Strong A. W, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thompson D. J, Tibaldo L, Tinivella M, Torres D. F, Tosti G, Troja E, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite A. P, Winer B. L, Wood K. S, Wood M, Yang Z, Zimmer S

ASTROPHYSICAL JOURNAL 747 ( 2 ) 2012年03月 [査読有り]

DOI

Scopus

54

被引用数

(Scopus)
SEARCH FOR DARK MATTER SATELLITES USING FERMI-LAT

Ackermann M, Albert A, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bottacini E, Brandt T. J, Bregeon J, Brigida M, Bruel P, Buehler R, Burnett T. H, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, de Palma F, Dermer C. D, Digel S. W, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Essig R, Falletti L, Favuzzi C, Fegan S. J, Focke W. B, Fukazawa Y, Funk S, Fusco P, Gargano F, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Guiriec S, Gustafsson M, Hadasch D, Hayashida M, Hou X, Hughes R. E, Johnson R. P, Johnson A. S, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lionetto A. M, Garde M. Llena, Longo F, Loparco F, Lovellette M. N, Lubrano P, Mazziotta M. N, McEnery J. E, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Norris J. P, Nuss E, Ohsugi T, Okumura A, Orlando E, Ormes J. F, Ozaki M, Paneque D, Pelassa V, Pierbattista M, Piron F, Pivato G, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Ritz S, Sadrozinski H. F. -W, Sehgal N, Sgro C, Siskind E. J, Spinelli P, Strigari L, Suson D. J, Tajima H, Takahashi H, Tanaka T, Thayer J. G, Thayer J. B, Tibaldo L, Tinivella M, Torres D. F, Troja E, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yang Z, Zalewski S, Zimmer S

ASTROPHYSICAL JOURNAL 747 ( 2 ) 2012年03月 [査読有り]

DOI

Scopus

92

被引用数

(Scopus)
Discovery of an unidentified Fermi object as a black widow-like millisecond pulsar

A. K.H. Kong, R. H.H. Huang, K. S. Cheng, J. Takata, Y. Yatsu, C. C. Cheung, D. Donato, L. C.C. Lin, J. Kataoka, Y. Takahashi, K. Maeda, C. Y. Hui, P. H.T. Tam

Astrophysical Journal Letters 747 ( 1 ) 2012年03月

　概要を見る

The Fermi γ-ray Space Telescope has revolutionized our knowledge of the γ-ray pulsar population, leading to the discovery of almost 100 γ-ray pulsars and dozens of γ-ray millisecond pulsars (MSPs). Although the outer-gap model predicts different sites of emission for the radio and γ-ray pulsars, until now all of the known γ-ray MSPs have been visible in the radio. Here we report the discovery of a "radio-quiet" γ-ray-emitting MSP candidate by using Fermi, Chandra, Swift, and optical observations. The X-ray and γ-ray properties of the source are consistent with known γ-ray pulsars. We also found a 4.63 hr orbital period in optical and X-ray data. We suggest that the source is a black widow-like MSP with a 0.1 M ⊙ late-type companion star. Based on the profile of the optical and X-ray light curves, the companion star is believed to be heated by the pulsar while the X-ray emissions originate from pulsar magnetosphere and/or from intrabinary shock. No radio detection of the source has been reported yet, and although no γ-ray/radio pulsation has been found we estimate that the spin period of the MSP is 3-5 ms based on the inferred γ-ray luminosity. © 2012 The American Astronomical Society. All rights reserved.

DOI

Scopus

53

被引用数

(Scopus)
SUZAKU X-RAY FOLLOW-UP OBSERVATIONS OF SEVEN UNASSOCIATED FERMI-LAT GAMMA-RAY SOURCES AT HIGH GALACTIC LATITUDES

Y. Takahashi, J. Kataoka, T. Nakamori, K. Maeda, R. Makiya, T. Totani, C. C. Cheung, L. Stawarz, L. Guillemot, P. C. C. Freire, I. Cognard

ASTROPHYSICAL JOURNAL 747 ( 1 ) 64 - 79 2012年03月 [査読有り]

　概要を見る

We report on our second-year campaign of X-ray follow-up observations of unidentified Fermi Large Area Telescope (LAT) gamma-ray sources at high Galactic latitudes (vertical bar b vertical bar > 10 degrees) using the X-ray Imaging Spectrometer on board the Suzaku X-ray Observatory. In this second year of the project, seven new targets were selected from the First Fermi-LAT Catalog, and studied with 20-40 ks effective Suzaku exposures. We detected an X-ray point source coincident with the position of the recently discovered millisecond pulsar (MSP) PSR J2302+4442 within the 95% confidence error circle of 1FGL J2302.8+4443. The X-ray spectrum of the detected counterpart was well fit by a blackbody model with temperature of kT similar or equal to 0.3 keV, consistent with an origin of the observed X-ray photons from the surface of a rotating magnetized neutron star. For four other targets that were also recently identified with a normal pulsar (1FGL J0106.7+4853) and MSPs (1FGL J1312.6+0048, J1902.0-5110, and J2043.2+1709), only upper limits in the 0.5-10 keV band were obtained at the flux levels of similar or equal to 10(-14) erg cm(-2) s(-1). A weak X-ray source was found in the field of 1FGL J1739.4+8717, but its association with the variable gamma-ray emitter could not be confirmed with the available Suzaku data alone. For the remaining Fermi-LAT object 1FGL J1743.8-7620 no X-ray source was detected within the LAT 95% error ellipse. We briefly discuss the general properties of the observed high Galactic-latitude Fermi-LAT objects by comparing their multiwavelength properties with those of known blazars and MSPs.

DOI

Scopus

20

被引用数

(Scopus)
Limits on large extra dimensions based on observations of neutron stars with the Fermi-LAT

M. Ajello, L. Baldini, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, C. Cecchi, E. Charles, A. Chekhtman, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, S. Cutini, A. De Angelis, F. De Palma, C. D. Dermer, E. Do Couto E Silva, P. S. Drell, A. Drlica-Wagner, T. Enoto, C. Favuzzi, S. J. Fegan, E. C. Ferrara, Y. Fukazawa, P. Fusco, F. Gargano, D. Gasparrini, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, P. Graham, I. A. Grenier, S. Guiriec, M. Gustafsson, D. Hadasch, M. Hayashida, R. E. Hughes, A. S. Johnson, T. Kamae, H. Katagiri, J. Kataoka, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, A. M. Lionetto, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, M. N. Mazziotta, P. F. Michelson, W. Mitthumsiri, T. Mizuno, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, J. P. Norris, E. Nuss, T. Ohsugi, A. Okumura, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, M. Pesce-Rollins, M. Pierbattista, F. Piron, G. Pivato, S. Rainò, M. Razzano, S. Ritz, M. Roth, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, C. Sgrò, E. J. Siskind, G. Spandre, P. Spinelli

Journal of Cosmology and Astroparticle Physics 2012 ( 2 ) 2012年02月

　概要を見る

We present limits for the compactification scale in the theory of Large Extra Dimensions (LED) proposed by Arkani-Hamed, Dimopoulos, and Dvali. We use 11 months of data from the Fermi Large Area Telescope (Fermi-LAT) to set gamma ray flux limits for 6 gamma-ray faint neutron stars (NS). To set limits on LED we use the model of Hannestad and Raffelt (HR) that calculates the Kaluza-Klein (KK) graviton production in supernova cores and the large fraction subsequently gravitationally bound around the resulting NS. The predicted decay of the bound KK gravitons to γγ should contribute to the flux from NSs. Considering 2 to 7 extra dimensions of the same size in the context of the HR model, we use Monte Carlo techniques to calculate the expected differential flux of gamma-rays arising from these KK gravitons, including the effects of the age of the NS, graviton orbit, and absorption of gamma-rays in the magnetosphere of the NS. We compare our Monte Carlo-based differential flux to the experimental differential flux using maximum likelihood techniques to obtain our limits on LED. Our limits are more restrictive than past EGRET-based optimistic limits that do not include these important corrections. Additionally, our limits are more stringent than LHC based limits for 3 or fewer LED, and comparable for 4 LED. We conclude that if the effective Planck scale is around a TeV, then for 2 or 3 LED the compactification topology must be more complicated than a torus. © 2012 IOP Publishing Ltd and SISSA.

DOI

Scopus

6

被引用数

(Scopus)
Development of a scintillation detector using a MPPC as an alternative to an APD

T. Miura, T. Nakamori, J. Kataoka, T. Kato, K. Sato, Y. Ishikawa, K. Yamamura, N. Kawabata

JOURNAL OF INSTRUMENTATION 7 ( 2 ) C020306 2012年02月 [査読有り]

　概要を見る

We conducted a study to examine the performance of the multi-pixel photon counter(MPPC). The MPPC is a novel type of semiconductor photodetector consisting of multiple avalanche photodiode (APD) pixels operated in Geiger mode. Whereas the MPPC offers a great advantage in signal multiplication comparable to that achieved by the photomultiplier tube (PMT), the detection of weak scintillation light signals is difficult due to the severe contamination of dark counts. In this study, we first compared the energy resolutions and energy thresholds of a 3x3 mm(2) MPPC with those of a 3x3 mm(2) APD as scintillation detectors. The MPPC and APD were optically coupled with 5x5x5 mm(3) scintillation crystals of BGO, Tl:CsI, Pr:LuAG, and YAG. It turned out that the APD had better energy resolutions for 662 keV gamma-rays, while the MPPC had lower energy thresholds as measured using a test pulse. Despite the low energy thresholds, it is difficult for the MPPC to detect low energy gamma-rays due to the contamination of dark counts. Secondly, we applied a coincidence technique to discriminate weak gamma-ray signals from dark counts by using scintillation detectors that consisted of a 2x2 MPPC-array optically coupled with 10x10x10 mm(3) crystals of GSO, BGO, and Pr: LuAG. With this technique, we demonstrated that dark counts achieved a rejection efficiency of more than 99.8%. As a result, 22.2 keV gamma-rays were successfully detected with a GSO scintillator as measured at + 20 degrees C.

DOI

Scopus

2

被引用数

(Scopus)
EXPLORING THE CENTRAL SUB-PARSEC REGION OF THE gamma-RAY BRIGHT RADIO GALAXY 3C 84 WITH VLBA AT 43 GHz IN THE PERIOD OF 2002-2008

Kenta Suzuki, Hiroshi Nagai, Motoki Kino, Jun Kataoka, Keiichi Asada, Akihiro Doi, Makoto Inoue, Monica Orienti, Gabriele Giovannini, Marcello Giroletti, Anne Lahteenmaki, Merja Tornikoski, Jonathan Leon-Tavares, Uwe Bach, Seiji Kameno, Hideyuki Kobayashi

ASTROPHYSICAL JOURNAL 746 ( 2 ) 2012年02月 [査読有り]

　概要を見る

Following the discovery of a new radio component right before the GeV gamma-ray detection since 2008 August by the Fermi Gamma-ray Space Telescope, we present a detailed study of the kinematics and light curve on the central sub-parsec scale of 3C 84 using the archival Very Long Baseline Array 43 GHz data covering the period between 2002 January and 2008 November. We find that the new component "C3," previously reported by the observations with the Very Long Baseline Interferometer Exploration of Radio Astrometry, was already formed in 2003. The flux density of C3 increases moderately until 2008, and then it becomes brighter rapidly after 2008. The radio core, C1, also shows a similar trend. The apparent speed of C3 with reference to the core C1 shows moderate acceleration from 0.10c to 0.47c between 2003 November and 2008 November, but is still sub-relativistic. We further try to fit the observed broadband spectrum by the one-zone synchrotron self-Compton model using the measured apparent speed of C3. The fit can reproduce the observed gamma-ray emission, but does not agree with the observed radio spectral index between 22 and 43 GHz.

DOI

Scopus

53

被引用数

(Scopus)
Development of a gamma-ray imager using a large area monolithic 4× 4 MPPC array for a future PET scanner

Nakamori, T, Kato, T, Kataoka, J, Miura, T, Matsuda, H, Sato, K, Ishikawa, Y, Yamamura, K, Kawabata, N, Ikeda, H, Sato, G, Kamada, K

Journal of Instrumentaion 7 ( 1 ) C01083 - 13pp 2012年01月 [査読有り]

DOI

Scopus

19

被引用数

(Scopus)
Periodic Emission from the Gamma-Ray Binary 1FGL J1018.6-5856

SCIENCE 335 ( 6065 ) 189 - 193 2012年01月 [査読有り]

DOI

Scopus

91

被引用数

(Scopus)
13pSP-1 CTA報告38 : 全体報告(13pSP 高エネルギーガンマ線(CTA等),宇宙線・宇宙物理領域)

手嶋政廣, 窪秀利, 戸谷友則, 浅野勝晃, 粟根悠介, 井岡邦仁, 井上進, 井上芳幸, 上野遥, 梅原克典, 大石理子, 大岡秀行, 大平豊, 奥田武志, 奥村曉, 折戸玲子, 加賀谷美佳, 格和純, 片岡淳, 片桐秀明, 株木重人, 川中宣太, 岸本哲朗, 北本兼続, 櫛田淳子, 郡司修一, 郡和範, 小谷一仁, 小山志勇, 今野裕介, 齋藤浩二, 斎藤雄太朗, 榊直人, 峪中良介, 佐々木浩人, 澤田真理, 柴田徹, 渋谷明伸, 周小渓, 菅原隆希, 高橋慶太郎, 高橋弘充, 高見一, 田島宏康, 田中駿也, 田中真伸, 千川道幸, 寺田幸功, 當真賢二, 門叶冬樹, 鳥居和史, 内藤統也, 中嶋大輔, 長滝重博, 中森健之, 中山和則, 西嶋恭司, 野里明香, 萩原亮太, 畑中謙一郎, 馬場浩則, 早川貴敬, 林田将明, 原敏, 馬場彩, 日高直哉, 深沢泰司, 福井康雄, 藤田裕, 松本浩典, 水野恒史, 村石浩, 村瀬孔大, 森浩二, 柳田昭平, 山崎了, 山本常夏, 山本宏昭, 吉越貴紀, 吉田篤正, 吉田龍生, 李兆衡

日本物理学会講演概要集 67.2.1 114 2012年

DOI CiNii
Development of a MPPC-based DOI-PET module with submillimeter 3-D resolution

Aya Kishimoto, Jun Kataoka, Takuya Kato, Takamasa Miura, Takeshi Nakamori, Kei Kamada, Shigeyuki Nakamura, Kenichi Sato, Yoshitaka Ishikawa, Kazuhisa Yamamura, Seiichi Yamamoto

2012 IEEE NUCLEAR SCIENCE SYMPOSIUM AND MEDICAL IMAGING CONFERENCE RECORD (NSS/MIC) 3128 - 3133 2012年 [査読有り]

　概要を見る

We are proposing a novel design for a module with depth of interaction (DOI) capability for gamma rays by measuring the pulse-height ratio of double-sided Multi-Pixel Photon Counters (MPPCs) coupled at both ends of a scintillation crystal block. Thanks to newly developed monolithic MPPC arrays consisting of 4 x 4 channels with a three-side buttable package, the module is very thin and compact, thereby enabling less dead space between each module when arranged into a fully designed gantry. To demonstrate our concept of a DOI measuring technique, we first made a 1-D crystal array consisting of five Ce-doped Gd3Al2Ga3O12 (Ce:GAGG) cubic crystals measuring 3 x 3 x 3 mm(3) in size, separated by a layer of air. When the light signals output from both ends are read with the MPPCs, the position of each crystal is clearly distinguished with a spatial uncertainty of 0.48 +/- 0.03 mm. For 3-D measurements, we then fabricated three different type arrays: [A] 4 x 4 x 4 matrix of 3 x 3 x 3 mm(3) pixels, [B] 5 x 5 x 5 matrix of 2 x 2 x 2 mm(3) pixels, and [C] 10 x 10 x 10 matrix of 1 x 1 x 1 mm(3) pixels, with each pixel divided by a BaSO4 reflector in the 2-D direction and by a layer of air in the DOI direction. We demonstrated that the 3-D position of each Ce:GAGG pixel was clearly distinguished when illuminated by 662 keV gamma rays uniformly. Average energy resolutions of 9.8 +/- 0.8 %, 9.8 +/- 0.9 %, and 13.2 +/- 1.7 % were obtained for types A, B and C, respectively. These results suggest that our proposed method is simple and offers promise in achieving 1 mm 3-D spatial resolution for future medical imaging, particularly in positron emission tomography (PET).
The cosmic-ray and gas content of the Cygnus region as measured in γ-rays by the Fermi Large Area Telescope

M. Ackermann, M. Ajello, A. Allafort, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, A. Belfiore, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, E. Bottacini, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, C. Cecchi, A. Chekhtman, S. Ciprini, R. Claus, J. Cohen-Tanugi, A. De Angelis, F. De Palma, C. D. Dermer, E. Do Couto E Silva, P. S. Drell, D. Dumora, C. Favuzzi, S. J. Fegan, W. B. Focke, P. Fortin, Y. Fukazawa, P. Fusco, F. Gargano, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, L. Guillemot, S. Guiriec, D. Hadasch, Y. Hanabata, A. K. Harding, M. Hayashida, K. Hayashi, E. Hays, G. Jóhannesson, A. S. Johnson, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, S. H. Lee, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, P. Martin, M. N. Mazziotta, J. E. McEnery, J. Mehault, P. F. Michelson, W. Mitthumsiri, T. Mizuno, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, M. Naumann-Godo, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, A. Okumura, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, D. Parent, M. Pesce-Rollins, M. Pierbattista, F. Piron

Astronomy and Astrophysics 538 2012年

　概要を見る

Context. The Cygnus region hosts a giant molecular-cloud complex that actively forms massive stars. Interactions of cosmic rays with interstellar gas and radiation fields make it shine at γ-ray energies. Several γ-ray pulsars and other energetic sources are seen in this direction. Aims. In this paper we analyze the γ-ray emission measured by the Fermi Large Area Telescope (LAT) in the energy range from 100 MeV to 100 GeV in order to probe the gas and cosmic-ray content on the scale of the whole Cygnus complex. The γ-ray emission on the scale of the central massive stellar clusters and from individual sources is addressed elsewhere. Methods. The signal from bright pulsars is greatly reduced by selecting photons in their off-pulse phase intervals. We compare the diffuse γ-ray emission with interstellar gas maps derived from radio/mm-wave lines and visual extinction data. A general model of the region, including other pulsars and γ-ray sources, is sought. Results. The integral H i emissivity above 100 MeV averaged over the whole Cygnus complex amounts to [2.06 ± 0.11 (stat.) -0.84+0.15(syst.)] × 10 -26 photons s -1 sr -1 H-atom -1, where the systematic error is dominated by the uncertainty on the H i opacity to calculate its column densities. The integral emissivity and its spectral energy distribution are both consistent within the systematics with LAT measurements in the interstellar space near the solar system. The average X CO = N(H 2)/W CO ratio is found to be [1.68 ± 0.05 (stat.) -0.10+0.87(HI opacity)] × 10 20 molecules cm -2 (K km s -1) -1, consistent with other LAT measurements in the Local Arm. We detect significant γ-ray emission from dark neutral gas for a mass corresponding to ~40% of what is traced by CO. The total interstellar mass in the Cygnus complex inferred from its γ-ray emission amounts to 8 -1+5 × 10 6 M ⊙ at a distance of 1.4 kpc. Conclusions. Despite the conspicuous star formation activity and high masses of the interstellar clouds, the cosmic-ray population in the Cygnus complex averaged over a few hundred parsecs is similar to that of the local interstellar space. © 2012 ESO.

DOI

Scopus

56

被引用数

(Scopus)
The ASTRO-H X-ray observatory

Tadayuki Takahashi, Kazuhisa Mitsuda, Richard Kelley, Henri Aarts, Felix Aharonian, Hiroki Akamatsu, Fumie Akimotoe, Steve Allen, Naohisa Anabuki, Lorella Angelini, Keith Arnaud, Makoto Asai, Marc Audard, Hisamitsu Awaki, Philipp Azzarello, Chris Baluta, Aya Bamba, Nobutaka Bando, Mark Bautz, Roger Blandford, Kevin Boyce, Greg Brown, Ed Cackett, Maria Chernyakova, Paolo Coppi, Elisa Costantini, Jelle De Plaa, Jan Willem Den Herder, Michael DiPirro, Chris Done, Tadayasu Dotani, John Doty, Ken Ebisawa, Megan Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew Fabian, Carlo Ferrigno, Adam Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Stefan Funk, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi Gallo, Poshak Gandhi, Keith Gendreau, Kirk Gilmore, Daniel Haas, Yoshito Haba, Kenji Hamaguchi, Isamu Hatsukade, Takayuki Hayashi, Kiyoshi Hayashida, Junko Hiraga, Kazuyuki Hirose, Ann Hornschemeier, Akio Hoshino, John Hughes, Una Hwang, Ryo Iizuka, Yoshiyuki Inoue, Kazunori Ishibashi, Manabu Ishida, Kosei Ishimura, Yoshitaka Ishisaki, Masayuki Ito, Naoko Iwat, Naoko Iyomoto, Jelle Kaastr, Timothy Kallman, Tuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Hajime Kawahara, Madoka Kawaharada, Nobuyuki Kawai, Shigeo Kawasaki, Dmitry Khangaluyan, Caroline Kilbourne, Masashi Kimura, Kenzo Kinugasaa, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Tatsuro Kosaka, Alex Koujelev, Katsuji Koyama, Hans Krimm, Aya Kubota, Hideyo Kunieda, Stephanie LaMass, Philippe Laurent, Francois Lebrun, Maurice Leutenegger, Olivier Limousin, Michael Loewenstein, Knox Long, David Lumb

Proceedings of SPIE - The International Society for Optical Engineering 8443 2012年

　概要を見る

The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly successful X-ray missions initiated by the Institute of Space and Astronautical Science (ISAS). ASTRO-H will investigate the physics of the highenergy universe via a suite of four instruments, covering a very wide energy range, from 0.3 keV to 600 keV. These instruments include a high-resolution, high-Throughput spectrometer sensitive over 0.3-12 keV with high spectral resolution of ?E 5 7 eV, enabled by a micro-calorimeter array located in the focal plane of thin-foil X-ray optics; hard X-ray imaging spectrometers covering 5-80 keV, located in the focal plane of multilayer-coated, focusing hard X-ray mirrors; a wide-field imaging spectrometer sensitive over 0.4-12 keV, with an X-ray CCD camera in the focal plane of a soft X-ray telescope; and a non-focusing Compton-camera type soft gamma-ray detector, sensitive in the 40-600 keV band. The simultaneous broad bandpass, coupled with high spectral resolution, will enable the pursuit of a wide variety of important science themes. © 2012 SPIE.

DOI

Scopus

118

被引用数

(Scopus)
Γ-ray emission from the Perseus cluster of galaxies observed with the MAGIC telescopes

P. Colin, D. Eisenacher, D. Hildebrand, S. Lombardi, E. Lindfors, D. Paneque, S. Partini, F. Prada, J. Sitarek, F. Zandanel, Magic Collaboration, T. Dauser, M. Kadler, F. Krauss, J. Kataoka, C. Pfrommer, A. Pinzke, Y. Takahashi, S. Wilbert, J. Wilms

AIP Conference Proceedings 1505 578 - 581 2012年

　概要を見る

The Perseus cluster of galaxies is a nearby cool-core cluster with an intra-clustermedium (ICM) characterized by very high central densities. The observation of the Perseus cluster with the MAGIC telescopes, during 85 h from 2009 to 2011, resulted in the discovery of 2 point-like sources at very high energy (>100 GeV, VHE) coinciding with the central radio galaxy NGC1275 and the radio galaxy IC310. The γ-ray properties of these 2 sources are presented, taking into account contemporaneous Fermi-LAT as well as multi-wavelength data. Flux variability and spectral energy distribution shapes indicate that the VHE γ-rays do not originate from large-scale interaction of the radio galaxies with ICM but more likely from the active nuclei of these two galaxies. They could be both misaligned version of BL Lac objects, the most common TeV AGN. Our results provide vital clues to understand emission mechanisms of such misaligned objects, and how they may be related to the beamed emission seen in BL Lacs. No evidence of large-scale VHE γ-ray emission from hadronic cosmic ray (CR) interactions with the ICM has been found. The flux upper limit above 1 TeV reaches the signal expected by some theoretical models, constraining the cluster CR physics. In the framework of the hadronicmodel of the radiomini-halos, this limit implies aminimal magnetic field ranging from 4-9μG for the central cluster region. © 2012 American Institute of Physics.

DOI

Scopus

2

被引用数

(Scopus)
Sub-geiger mode single-photon detector using a low-darkcurrent InGaAs avalanche photodiode

Yoshito Miyamoto, Kenji Tsujino, Jun Kataoka, Akihisa Tomita

European Conference on Optical Communication, ECOC 2012年

　概要を見る

We have developed a single-photon detector that uses an InGaAs avalanche photodiode (APD) operating in sub-Geiger mode. Sub-Geiger mode operation is a technique in which an APD is operated at a bias voltage that is lower than the breakdown voltage. This mode considerably reduces afterpulse probability, and single photons that arrive randomly can be detected. In the present study, we reduced the dark count rate of the sub-Geiger mode single-photon detector by using a low-darkcurrent InGaAs APD. Consequently, we obtained a dark count rate (DCR) of 5.6 counts per second (cps) with single-photon detection efficiency (SPDE) of 0.2%. Our single-photon detector is comparable in DCR to that of superconducting nanowire single-photon detectors. © 2012 OSA.

DOI

Scopus

1

被引用数

(Scopus)
In-flight measurement of the absolute energy scale of the Fermi Large Area Telescope

Ackermann M, Ajello M, Allafort A, Atwood W. B, Axelsson M, Baldini L, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cutini S, de Palma F, Dermer C. D, Digel S. W, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Dubois R, Enoto T, Falletti L, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Fukazawa Y, Funk S, Fusco P, Gargano F, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grove J. E, Guiriec S, Hadasch D, Hayashida M, Hays E, Hughes R. E, Johannesson G, Johnson A. S, Johnson T. J, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Longo F, Loparco F, Lovellette M. N, Lubrano P, Madejski G. M, Mazziotta M. N, McEnery J. E, Michelson P. F, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pesce-Rollins M, Pierbattista M, Piron F, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Sgro C, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Suson D. J, Takahashi H, Tanaka T, Thayer J. G, Thayer J. B, Thompson D. J, Tibaldo L, Tosti G, Troja E, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yang Z, Zimmer S

ASTROPARTICLE PHYSICS 35 ( 6 ) 346 - 353 2012年01月 [査読有り]

DOI

Scopus

40

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE SUPERNOVA REMNANT G8.7-0.1

Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chekhtman A, Ciprini S, Claus R, Cohen-Tanugi J, Cutini S, de Angelis A, de Palma F, Dermer C. D, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Dubois R, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Frailis M, Fukazawa Y, Fukui Y, Fusco P, Gargano F, Gasparrini D, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grove J. E, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashi K, Hays E, Itoh R, Johannesson G, Johnson A. S, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kubo H, Kuss M, Lande J, Latronico L, Lee S. -H, Lionetto A. M, Longo F, Loparco F, Lovellette M. N, Lubrano P, Mazziotta M. N, Mehault J, Michelson P. F, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nishino S, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Paneque D, Parent D, Pelassa V, Pesce-Rollins M, Pierbattista M, Piron F, Porter T. A, Raino S, Rando R, Reimer A, Reimer O, Reposeur T, Roth M, Sadrozinski H. F. -W, Sgro C, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Suson D. J, Tajima H, Takahashi H, Tanaka T, Thayer J. G, Thayer J. B, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Troja E, Uchiyama Y, Uehara T, Usher T. L, Vandenbroucke J, Van Etten A, Vasileiou V, Vianello G, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yamamoto H, Yamazaki R, Yang Z, Yasuda H, Ziegler M, Zimmer S

ASTROPHYSICAL JOURNAL 744 ( 1 ) 2012年01月 [査読有り]

DOI

Scopus

46

被引用数

(Scopus)
Measurement of separate cosmic-ray electron and positron spectra with the fermi large area telescope

M. Ackermann, M. Ajello, A. Allafort, W.B. Atwood, L. Baldini, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, R.D. Blandford, E.D. Bloom, E. Bonamente, A.W. Borgland, A. Bouvier, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, S. Buson, G.A. Caliandro, R.A. Cameron, P.A. Caraveo, J.M. Casandjian, C. Cecchi, E. Charles, A. Chekhtman, C.C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, S. Cutini, A. De Angelis, F. De Palma, C.D. Dermer, S.W. Digel, E. Do Couto E Silva, P.S. Drell, A. Drlica-Wagner, C. Favuzzi, S.J. Fegan, E.C. Ferrara, W.B. Focke, P. Fortin, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, S. Germani, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I.A. Grenier, J.E. Grove, S. Guiriec, M. Gustafsson, D. Hadasch, A.K. Harding, M. Hayashida, R.E. Hughes, G. Jóhannesson, A.S. Johnson, T. Kamae, H. Katagiri, J. Kataoka, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, M. Lemoine-Goumard, M. Llena Garde, F. Longo, F. Loparco, M.N. Lovellette, P. Lubrano, G.M. Madejski, M.N. Mazziotta, J.E. McEnery, P.F. Michelson, W. Mitthumsiri, T. Mizuno, A.A. Moiseev, C. Monte, M.E. Monzani, A. Morselli, I.V. Moskalenko, S. Murgia, T. Nakamori, P.L. Nolan, J.P. Norris, E. Nuss, M. Ohno, T. Ohsugi, A. Okumura, N. Omodei, E. Orlando, J.F. Ormes, M. Ozaki, D. Paneque, D. Parent, M. Pesce-Rollins, M. Pierbattista, F. Piron, G. Pivato, T.A. Porter, S. Rainò, R. Rando, M. Razzano, S. Razzaque, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, R.W. Romani, M. Roth, H.F.-W. Sadrozinski, C. Sbarra, T.L. Schalk, C. Sgrò, E.J. Siskind, G. Spandre, P. Spinelli, A.W. Strong, H. Takahashi, T. Takahashi, T. Tanaka, J.G. Thayer, J.B. Thayer, L. Tibaldo, M. Tinivella, D.F. Torres, G. Tosti, E. Troja, Y. Uchiyama, T.L. Usher, J. Vandenbroucke, V. Vasileiou, G. Vianello, V. Vitale, A.P. Waite, B.L. Winer, K.S. Wood, M. Wood, Z. Yang, S. Zimmer

Physical Review Letters 108 ( 1 ) 2012年 [査読有り]

　概要を見る

We measured separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Because the instrument does not have an onboard magnet, we distinguish the two species by exploiting Earth's shadow, which is offset in opposite directions for opposite charges due to Earth's magnetic field. We estimate and subtract the cosmic-ray proton background using two different methods that produce consistent results. We report the electron-only spectrum, the positron-only spectrum, and the positron fraction between 20 and 200 GeV. We confirm that the fraction rises with energy in the 20-100 GeV range. The three new spectral points between 100 and 200 GeV are consistent with a fraction that is continuing to rise with energy. © 2012 American Physical Society.

DOI

Scopus

564

被引用数

(Scopus)
Soft Gamma-ray Detector for the ASTRO-H mission

Watanabe Shin, Talima Hiroyasu, Fukazawa Yasushi, Blandford Roger, Enoto Teruaki, Kataoka Jun, Kawaharada Madoka, Kokubun Motohide, Laurent Philippe, Lebrun Francois, Limousin Olivier, Madejski Greg, Makishima Kazuo, Mizuno Tsunefumi, Nakamori Takeshi, Nakazawa Kazuhiro, Mori Kunishiro, Odaka Hirokazu, Ohno Masanori, Ohta Masayuki, Sato Goro, Sato Rie, Takeda Shin'ichiro, Takahashi Hiromitsu, Takahashi Tadayuki, Tanaka Takaaki, Tashiro Makoto, Terada Yukikatsu, Uchiyama Hideki, Uchiyama Yasunobu, Yamada Shinya, Yatsu Yoichi, Yonetoku Daisuke, Yuasa Takayuki

SPACE TELESCOPES AND INSTRUMENTATION 2012: ULTRAVIOLET TO GAMMA RAY 8443 2012年 [査読有り]

DOI

Scopus

34

被引用数

(Scopus)
フェルミ・バブルから探る銀河系中心の過去の活動性

片岡淳, 戸谷友則, 井岡邦仁

日本天文学会誌 105 ( 9 ) 542 - 553 2012年

CiNii
THE SECOND CATALOG OF ACTIVE GALACTIC NUCLEI DETECTED BY THE FERMI LARGE AREA TELESCOPE

Ackermann M, Ajello M, Allafort A, Antolini E, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bottacini E, Bouvier A, Bregeon J, Brigida M, Bruel P, Buehler R, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cavazzuti E, Cecchi C, Charles E, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Costamante L, Cutini S, de Angelis A, de Palma F, Dermer C. D, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Escande L, Favuzzi C, Fegan S. J, Ferrara E. C, Finke J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grove J. E, Guiriec S, Gustafsson M, Hadasch D, Hayashida M, Hays E, Healey S. E, Horan D, Hou X, Hughes R. E, Iafrate G, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Knodlseder J, Kuss M, Lande J, Larsson S, Latronico L, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Mazziotta M. N, McConville W, McEnery J. E, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Okumura A, Omodei N, Orienti M, Orlando E, Ormes J. F, Ozaki M, Paneque D, Parent D, Pesce-Rollins M, Pierbattista M, Piranomonte S, Piron F, Pivato G, Porter T. A, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Ritz S, Rochester L. S, Romani R. W, Roth M, Sanchez D. A, Sbarra C, Scargle J. D, Schalk T. L, Sgro C, Shaw M. S, Siskind E. J, Spandre G, Spinelli P, Strong A. W, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. G, Thayer J. B, Thompson D. J, Tibaldo L, Tinivella M, Torres D. F, Tosti G, Troja E, Uchiyama Y, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite A. P, Wallace E, Wang P, Winer B. L, Wood D. L, Wood K. S, Zimmer S

ASTROPHYSICAL JOURNAL 743 ( 2 ) 2011年12月 [査読有り]

DOI

Scopus

558

被引用数

(Scopus)
Constraining dark matter models from a combined analysis of Milky Way satellites with the Fermi Large Area Telescope

M. Ackermann, M. Ajello, A. Albert, W. B. Atwood, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, B. Cañadas, P. A. Caraveo, J. M. Casandjian, C. Cecchi, E. Charles, A. Chekhtman, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, S. Cutini, A. De Angelis, F. De Palma, C. D. Dermer, S. W. Digel, E. Do Couto E Silva, P. S. Drell, A. Drlica-Wagner, L. Falletti, C. Favuzzi, S. J. Fegan, E. C. Ferrara, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, S. Guiriec, M. Gustafsson, D. Hadasch, M. Hayashida, E. Hays, R. E. Hughes, T. E. Jeltema, G. Jóhannesson, R. P. Johnson, A. S. Johnson, T. Kamae, H. Katagiri, J. Kataoka, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, A. M. Lionetto, M. Llena Garde, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, M. N. Mazziotta, J. E. McEnery, J. Mehault, P. F. Michelson, W. Mitthumsiri, T. Mizuno, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, M. Naumann-Godo, J. P. Norris, E. Nuss, T. Ohsugi, A. Okumura

Physical Review Letters 107 ( 24 ) 2011年12月

　概要を見る

Satellite galaxies of the Milky Way are among the most promising targets for dark matter searches in gamma rays. We present a search for dark matter consisting of weakly interacting massive particles, applying a joint likelihood analysis to 10 satellite galaxies with 24 months of data of the Fermi Large Area Telescope. No dark matter signal is detected. Including the uncertainty in the dark matter distribution, robust upper limits are placed on dark matter annihilation cross sections. The 95% confidence level upper limits range from about 10-26cmm3s-1 at 5 GeV to about 5×10-23cm3s-1 at 1 TeV, depending on the dark matter annihilation final state. For the first time, using gamma rays, we are able to rule out models with the most generic cross section (∼3×10-26cm3s-1 for a purely s-wave cross section), without assuming additional boost factors. © 2011 American Physical Society.

DOI

Scopus

522

被引用数

(Scopus)
シンポジウム「二次元放射線検出器の最前線」開催への思い

片岡淳

放射線 37 ( 4 ) 215 - 215 2011年12月

CiNii
Gas slit camera (GSC) onboard MAXI on ISS

Tatehiro Mihara, Motoki Nakajima, Mutsumi Sugizaki, Motoko Serino, Masaru Matsuoka, Mitsuhiro Kohama, Kazuyoshi Kawasaki, Hiroshi Tomida, Shiro Ueno, Nobuyuki Kawai, Jun Kataoka, Mikio Morii, Atsumasa Yoshida, Kazutaka Yamaoka, Satoshi Nakahira, Hitoshi Negoro, Naoki Isobe, Makoto Yamauchi, Ikuya Sakurai

Publications of the Astronomical Society of Japan 63 ( SPEC. ISSUE 3 ) 2011年11月

　概要を見る

The Gas Slit Camera (GSC) is an X-ray instrument on the MAXI (Monitor of All-sky X-ray Image) mission aboard the International Space Station. It is designed to scan the entire sky every 92-minute orbital period in the 2-30 keV band and to achieve the highest sensitivity among the X-ray all-sky monitors ever flown so far. The GSC employs large-area position-sensitive proportional counterswith a total detector area of 5350cm2. The on-board data processor has functions to format telemetry data as well as to control the high voltage of the proportional counters so as to protect them from particle irradiation. This paper describes the instruments, on-board data processing, telemetry data formats, and performance specifications expected from ground calibration tests. © 2011. Astronomical Society of Japan.

DOI

Scopus

152

被引用数

(Scopus)
A Cocoon of Freshly Accelerated Cosmic Rays Detected by Fermi in the Cygnus Superbubble

Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Bastieri D, Belfiore A, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bottacini E, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, de Angelis A, de Palma F, Dermer C. D, do Couto e, Silva E, Drell P. S, Dumora D, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Fukazawa Y, Fusco P, Gargano F, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Guillemot L, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashida M, Hayashi K, Hays E, Johannesson G, Johnson A. S, Kamae T, Katagiri H, Kataoka J, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Martin P, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mitthumsiri W, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Orlando E, Ormes J. F, Ozaki M, Paneque D, Parent D, Pesce-Rollins M, Pierbattista M, Piron F, Pohl M, Prokhorov D, Raino S, Rando R, Razzano M, Reposeur T, Ritz S, Parkinson P, M. Saz, Sgro C, Siskind E. J, Smith P. D, Spinelli P, Strong A. W, Takahashi H, Tanaka T, Thayer J. G, Thayer J. B, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Troja E, Uchiyama Y, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yang Z, Zimmer S, Bontemps S

SCIENCE 334 ( 6059 ) 1103 - 1107 2011年11月 [査読有り]

DOI

Scopus

271

被引用数

(Scopus)
Fermi Detection of a Luminous gamma-Ray Pulsar in a Globular Cluster

SCIENCE 334 ( 6059 ) 1107 - 1110 2011年11月 [査読有り]

DOI

Scopus

70

被引用数

(Scopus)
γ -Ray and parsec-scale jet properties of a complete sample of blazars from the mojave program

M. L. Lister, M. Aller, H. Aller, T. Hovatta, K. I. Kellermann, Y. Y. Kovalev, E. T. Meyer, A. B. Pushkarev, E. Ros, M. Ackermann, E. Antolini, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, M. Boeck, E. Bonamente, A. W. Borgland, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, C. S. Chang, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, S. Cutini, F. De Palma, C. D. Dermer, E. Do Couto E Silva, P. S. Drell, A. Drlica-Wagner, C. Favuzzi, S. J. Fegan, E. C. Ferrara, J. Finke, W. B. Focke, P. Fortin, Y. Fukazawa, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, S. Guiriec, D. Hadasch, M. Hayashida, E. Hays, D. Horan, R. E. Hughes, G. Jóhannesson, A. S. Johnson, M. Kadler, H. Katagiri, J. Kataoka, J. Knödlseder, M. Kuss, J. Lande, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, M. N. Mazziotta, W. McConville, J. E. McEnery, J. Mehault, P. F. Michelson, T. Mizuno, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, M. Naumann-Godo, S. Nishino

Astrophysical Journal 742 ( 1 ) 2011年11月

　概要を見る

We investigate the Fermi Large Area Telescope γ -ray and 15 GHz Very Long Baseline Array radio properties of a joint γ -ray and radio-selected sample of active galactic nuclei (AGNs) obtained during the first 11 months of the Fermi mission (2008 August 4-2009 July 5). Our sample contains the brightest 173 AGNs in these bands above declination -30° during this period, and thus probes the full range of γ -ray loudness (γ -ray to radio band luminosity ratio) in the bright blazar population. The latter quantity spans at least 4 orders of magnitude, reflecting a wide range of spectral energy distribution (SED) parameters in the bright blazar population. The BL Lac objects, however, display a linear correlation of increasing γ -ray loudness with synchrotron SED peak frequency, suggesting a universal SED shape for objects of this class. The synchrotron self-Compton model is favored for the γ -ray emission in these BL Lac objects over external seed photon models, since the latter predict a dependence of Compton dominance on Doppler factor that would destroy any observed synchrotron SED-peak-γ -ray-loudness correlation. The high-synchrotron peaked (HSP) BL Lac objects are distinguished by lower than average radio core brightness temperatures, and none display large radio modulation indices or high linear core polarization levels. No equivalent trends are seen for the flat-spectrum radio quasars (FSRQs) in our sample. Given the association of such properties with relativistic beaming, we suggest that the HSP BL Lac objects have generally lower Doppler factors than the lower-synchrotron peaked BL Lac objects or FSRQs in our sample.

DOI

Scopus

107

被引用数

(Scopus)
THE RADIO/GAMMA-RAY CONNECTION IN ACTIVE GALACTIC NUCLEI IN THE ERA OF THE FERMI LARGE AREA TELESCOPE

Ackermann M, Ajello M, Allafort A, Angelakis E, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Cannon A, Caraveo P. A, Casandjian J. M, Cavazzuti E, Cecchi C, Charles E, Chekhtman A, Cheung C. C, Ciprini S, Claus R, Cohen-Tanugi J, Cutini S, de Palma F, Dermer C. D, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Escande L, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fuhrmann L, Fukazawa Y, Fusco P, Gargano F, Gasparrini D, Gehrels N, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grandi P, Grenier I. A, Guiriec S, Hadasch D, Hayashida M, Hays E, Healey S. E, Johannesson G, Johnson A. S, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Lee S. -H, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Max-Moerbeck W, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Nishino S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Pavlidou V, Pelassa V, Pepe M, Pesce-Rollins M, Pierbattista M, Piron F, Porter T. A, Raino S, Razzano M, Readhead A, Reimer A, Reimer O, Richards J. L, Romani R. W, Sadrozinski H. F. -W, Scargle J. D, Sgro C, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Takahashi H, Tanaka T, Taylor G. B, Thayer J. G, Thayer J. B, Thompson D. J, Torres D. F, Tosti G, Tramacere A, Troja E, Vandenbroucke J, Vianello G, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yang Z, Ziegler M

ASTROPHYSICAL JOURNAL 741 ( 1 ) 2011年11月 [査読有り]

DOI

Scopus

124

被引用数

(Scopus)
Broad-line radio galaxies observed with fermi-lat: The origin of the GeV γ-ray emission

Kataoka, J, Stawarz, Stawarz, Takahashi, Y, Cheung, C. C, Cheung, C. C, Hayashida, M, Grandi, P, Burnett, T. H, Celotti, A, Fegan, S. J, Fortin, P, Maeda, K, Nakamori, T, Taylor, G. B, Tosti, G, Tosti, G, Digel, S. W, McConville, W, McConville, W, Finke, J, D'Ammando, F, D'Ammando, F

Astrophysical Journal 740 ( 1 ) 2011年10月

　概要を見る

We report on a detailed investigation of the γ-ray emission from 18 broad-line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope data. We confirm the previously reported detections of 3C 120 and 3C 111 in the GeV photon energy range; a detailed look at the temporal characteristics of the observed γ-ray emission reveals in addition possible flux variability in both sources. No statistically significant γ-ray detection of the other BLRGs was found, however, in the considered data set. Though the sample size studied is small, what appears to differentiate 3C 111 and 3C 120 from the BLRGs not yet detected in γ-rays is the particularly strong nuclear radio flux. This finding, together with the indications of the γ-ray flux variability and a number of other arguments presented, indicates that the GeV emission of BLRGs is most likely dominated by the beamed radiation of relativistic jets observed at intermediate viewing angles. In this paper we also analyzed a comparison sample of high-accretion-rate Seyfert 1 galaxies, which can be considered radio-quiet counterparts of BLRGs, and found that none were detected in γ-rays. A simple phenomenological hybrid model

DOI

Scopus

74

被引用数

(Scopus)
フェルミ衛星による広輝線電波銀河の観測：GeVガンマ線放射の起源

J.Kataoka

The Astrophysical Journal 740 ( 1 ) 29 - 44 2011年10月 [査読有り]

DOI

Scopus

74

被引用数

(Scopus)
Development micro-satellite TSUBAME for polarimetry of gamma-ray bursts

Yatsu, Y, Enomoto, T, Kawakami, K, Tokoyoda, K, Toizumi, T, Kawai, N, Ishizaka, K, Matsunaga, S, Nakamori, T, Kataoka, J, Kubo, S

Proc. of SPIE 8145 814508 2011年09月

DOI

Scopus

4

被引用数

(Scopus)
Improvement of Energy Thresholds for Scintillation Detectors Using a Monolithic 2 x 2 Multi-Pixel Photon Counter Array with a Coincidence Technique

Takamasa Miura, Takeshi Nakamori, Jun Kataoka, Takuya Kato, Kenichi Sato, Yoshitaka Ishikawa, Kazuhisa Yamamura, Nobuyuki Kawabata

JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 80 ( 9 ) 2011年09月

　概要を見る

The performance of a large-area, monolithic Hamamatsu multi-pixel photon counter (MPPC) was tested consisting of a 2 x 2 array of 3 x 3 mm(2) pixels. MPPC is a novel type of semiconductor photodetector comprising multiple avalanche photodiode (APD) pixels operated in Geiger mode. Despite its great advantage of signal multiplication comparable to that achieved with the photomultiplier tube (PMT), the detection of weak scintillation light signals is quite difficult due to the severe contamination of dark counts, which typically amounts to similar or equal to 1 Mcps/3 x 3 mm(2) at room temperature. In this study, a coincidence technique was applied for scintillation detectors to improve the detection efficiency for low energy gamma-rays. The detector consisted of a 10 x 10 x 10 mm(3) crystals of GSO, BGO, and Pr:LuAG optically coupled with the 2 x 2 MPPC-array. With this technique, we demonstrated that the contamination of dark counts was reduced with a rejection efficiency of more than 99.8%. As a result, 22.2 keV gamma-rays were successfully detected with a GSO scintillator as measured at +20 degrees C.

DOI

Scopus
Improvement of Energy Thresholds for Scintillation Detectors Using a Monolithic 2 x 2 Multi-Pixel Photon Counter Array with a Coincidence Technique

Takamasa Miura, Takeshi Nakamori, Jun Kataoka, Takuya Kato, Kenichi Sato, Yoshitaka Ishikawa, Kazuhisa Yamamura, Nobuyuki Kawabata

JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 80 ( 9 ) 094203 2011年09月 [査読有り]

　概要を見る

The performance of a large-area, monolithic Hamamatsu multi-pixel photon counter (MPPC) was tested consisting of a 2 x 2 array of 3 x 3 mm(2) pixels. MPPC is a novel type of semiconductor photodetector comprising multiple avalanche photodiode (APD) pixels operated in Geiger mode. Despite its great advantage of signal multiplication comparable to that achieved with the photomultiplier tube (PMT), the detection of weak scintillation light signals is quite difficult due to the severe contamination of dark counts, which typically amounts to similar or equal to 1 Mcps/3 x 3 mm(2) at room temperature. In this study, a coincidence technique was applied for scintillation detectors to improve the detection efficiency for low energy gamma-rays. The detector consisted of a 10 x 10 x 10 mm(3) crystals of GSO, BGO, and Pr:LuAG optically coupled with the 2 x 2 MPPC-array. With this technique, we demonstrated that the contamination of dark counts was reduced with a rejection efficiency of more than 99.8%. As a result, 22.2 keV gamma-rays were successfully detected with a GSO scintillator as measured at +20 degrees C.

DOI

Scopus
The Small Satellite ``Tsubame'' for Polarimetry of GRBs

Toizumi, T, Kawakami, K, Tokoyoda, K, Enomoto, T, Yatsu, Y, Kawai, N, Nakamori, T, Kataoka, J, Kubo, S

AIP Conference Proceedings 1357 355 - 357 2011年08月

DOI

Scopus
Constraints on dark matter models from a Fermi LAT search for high-energy cosmic-ray electrons from the Sun

M. Ajello, W. B. Atwood, L. Baldini, G. Barbiellini, D. Bastieri, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, E. Bottacini, A. Bouvier, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, C. Cecchi, E. Charles, A. Chekhtman, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Cutini, A. De Angelis, F. De Palma, C. D. Dermer, S. W. Digel, E. Do Couto E Silva, P. S. Drell, C. Favuzzi, S. J. Fegan, W. B. Focke, Y. Fukazawa, P. Fusco, F. Gargano, N. Gehrels, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, S. Guiriec, M. Gustafsson, D. Hadasch, G. Iafrate, G. Jóhannesson, A. S. Johnson, T. Kamae, H. Katagiri, J. Kataoka, M. Kuss, L. Latronico, A. M. Lionetto, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, M. N. Mazziotta, J. E. McEnery, P. F. Michelson, T. Mizuno, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, M. Naumann-Godo, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, J. H. Panetta, M. Pesce-Rollins, M. Pierbattista, F. Piron, S. Rainò, R. Rando, M. Razzano, A. Reimer, O. Reimer, S. Ritz, T. L. Schalk, C. Sgrò, J. Siegal-Gaskins, E. J. Siskind, P. D. Smith, G. Spandre, P. Spinelli, D. J. Suson

Physical Review D - Particles, Fields, Gravitation and Cosmology 84 ( 3 ) 2011年08月

　概要を見る

During its first year of data taking, the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope has collected a large sample of high-energy cosmic-ray electrons and positrons (CREs). We present the results of a directional analysis of the CRE events, in which we searched for a flux excess correlated with the direction of the Sun. Two different and complementary analysis approaches were implemented, and neither yielded evidence of a significant CRE flux excess from the Sun. We derive upper limits on the CRE flux from the Sun's direction, and use these bounds to constrain two classes of dark matter models which predict a solar CRE flux: (1) models in which dark matter annihilates to CREs via a light intermediate state, and (2) inelastic dark matter models in which dark matter annihilates to CREs. © 2011 American Physical Society.

DOI

Scopus

45

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF MARKARIAN 421: THE MISSING PIECE OF ITS SPECTRAL ENERGY DISTRIBUTION

ASTROPHYSICAL JOURNAL 736 ( 2 ) 2011年08月 [査読有り]

DOI

Scopus

294

被引用数

(Scopus)
The Small Satellite ``Tsubame'' for Polarimetry of GRBs

Toizumi, T, Kawakami, K, Tokoyoda, K, Enomoto, T, Yatsu, Y, Kawai, N, Nakamori, T, Kataoka, J, Kubo, S

AIP Conference Proceedings 1358 435 - 437 2011年08月

DOI

Scopus

1

被引用数

(Scopus)
Discovery of high-energy gamma-ray emission from the binary system PSR B1259-63/LS 2883 around periastron with Fermi

A. A. Abdo, M. Ackermann, M. Ajello, A. Allafort, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. Bonamente, A. W. Borgland, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, F. Camilo, P. A. Caraveo, C. Cecchi, E. Charles, S. Chaty, A. Chekhtman, M. Chernyakova, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, S. Corbel, S. Cutini, F. D'Ammando, A. De Angelis, P. R. Den Hartog, F. De Palma, C. D. Dermer, S. W. Digel, E. Do Couto E Silva, M. Dormody, P. S. Drell, A. Drlica-Wagner, R. Dubois, G. Dubus, D. Dumora, T. Enoto, C. M. Espinoza, C. Favuzzi, S. J. Fegan, E. C. Ferrara, W. B. Focke, P. Fortin, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, J. E. Grove, E. Grundstrom, S. Guiriec, C. Gwon, D. Hadasch, A. K. Harding, M. Hayashida, E. Hays, G. Jóhannesson, A. S. Johnson, T. J. Johnson, S. Johnston, T. Kamae, H. Katagiri, J. Kataoka, M. Keith, M. Kerr, J. Knödlseder, M. Kramer, M. Kuss, J. Lande, S. H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, R. N. Manchester, M. Marelli, M. N. Mazziotta

Astrophysical Journal Letters 736 ( 1 ) 2011年07月

　概要を見る

We report on the discovery of ≥100MeV γ-rays from the binary system PSR B1259-63/LS 2883 using the Large Area Telescope (LAT) on board Fermi. The system comprises a radio pulsar in orbit around a Be star. We report on LAT observations from near apastron to ∼128 days after the time of periastron, ∼tp , on 2010 December 15. No γ-ray emission was detected from this source when it was far from periastron. Faint γ-ray emission appeared as the pulsar approached periastron. At ∼tp + 30 days, the ≥100MeV γ-ray flux increased over a period of a few days to a peak flux 20-30 times that seen during the pre-periastron period, but with a softer spectrum. For the following month, it was seen to be variable on daily timescales, but remained at ∼(1-4) × 10-6 cm-2 s-1 before starting to fade at ∼tp + 57 days. The total γ-ray luminosity observed during this period is comparable to the spin-down power of the pulsar. Simultaneous radio and X-ray observations of the source showed no corresponding dramatic changes in radio and X-ray flux between the pre-periastron and post-periastron flares. We discuss possible explanations for the observed γ-ray-only flaring of the source. © 2011. The American Astronomical Society. All rights reserved.

DOI

Scopus

148

被引用数

(Scopus)
The development and performance of UV-enhanced APD-arrays for high resolution PET imaging coupled with pixelized Pr: LuAG crystal

Yoshino, M, Kataoka, J, Nakamori, T, Matsuda, H, Miura, T, Katou, T, Ishikawa, Y, Kawabata, N, Matsunaga, Y, Kamada, K, Usuki, Y, Yoshikawa, A, Yanagida, T

Nuclear Instruments and Methods in Physics Research Section A 643 ( 1 ) 57 - 63 2011年07月 [査読有り]

DOI

Scopus

10

被引用数

(Scopus)
DETECTION OF HIGH-ENERGY GAMMA-RAY EMISSION DURING THE X-RAY FLARING ACTIVITY IN GRB 100728A

Abdo A. A, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bhat P. N, Bissaldi E, Blandford R. D, Bonamente E, Bonnell J, Borgland A. W, Bouvier A, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chekhtman A, Chiang J, Ciprini S, Claus R, Connaughton V, Conrad J, Cutini S, de Angelis A, de Palma F, Dermer C. D, do Couto e, Silva E, Drell P. S, Dubois R, Favuzzi C, Fukazawa Y, Fusco P, Gargano F, Gehrels N, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Granot J, Grenier I. A, Guiriec S, Hadasch D, Hanabata Y, Hughes R. E, Johannesson G, Johnson A. S, Kamae T, Katagiri H, Kataoka J, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Longo F, Loparco F, Lott B, Lubrano P, Mazziotta M. N, McEnery J. E, Meszaros P, Michelson P. F, Mizuno T, Moiseev A. A, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Paciesas W. S, Pelassa V, Pesce-Rollins M, Pierbattista M, Piron F, Porter T. A, Racusin J. L, Raino S, Razzano M, Razzaque S, Reimer A, Reimer O, Reyes L. C, Roth M, Sadrozinski H. F. -W, Sgro C, Siskind E. J, Smith P. D, Sonbas E, Spandre G, Spinelli P, Stamatikos M, Strickman M. S, Takahashi H, Tanaka T, Tanaka Y, Thayer J. G, Thayer J. B, Torres D. F, Tosti G, Troja E, Uehara T, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vilchez N, Vitale V, von Kienlin A, Waite A. P, Wang P, Winer B. L, Wood K. S, Yamazaki R, Yang Z, Ziegler M, Piro L

ASTROPHYSICAL JOURNAL LETTERS 734 ( 2 ) 2011年06月 [査読有り]

DOI

Scopus

40

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF TWO GAMMA-RAY EMISSION COMPONENTS FROM THE QUIESCENT SUN

Abdo A. A, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, de Angelis A, de Palma F, Dermer C. D, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grillo L, Guiriec S, Hadasch D, Hays E, Hughes R. E, Iafrate G, Johannesson G, Johnson A. S, Johnson T. J, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lionetto A. M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Pelassa V, Pesce-Rollins M, Pierbattista M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Sadrozinski H. F. -W, Schalk T. L, Sgro C, Share G. H, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Strong A. W, Takahashi H, Tanaka T, Thayer J. G, Thayer J. B, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Troja E, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vianello G, Vilchez N, Vitale V, Vladimirov A. E, Waite A. P, Wang P, Winer B. L, Wood K. S, Yang Z, Ziegler M

ASTROPHYSICAL JOURNAL 734 ( 2 ) 2011年06月 [査読有り]

DOI

Scopus

123

被引用数

(Scopus)
OBSERVATIONS OF THE YOUNG SUPERNOVA REMNANT RX J1713.7-3946 WITH THE FERMI LARGE AREA TELESCOPE

Abdo A. A, Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Br, dt T. J, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Chaty S, Chekhtman A, Cheung C. C, Chiang J, Cillis A. N, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Corbel S, Cutini S, de Angelis A, de Palma F, Dermer C. D, Digel S. W, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Dubois R, Dumora D, Favuzzi C, Ferrara E. C, Fortin P, Frailis M, Fukazawa Y, Fukui Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashida M, Hayashi K, Hays E, Horan D, Jackson M. S, Johannesson G, Johnson A. S, Kamae T, Katagiri H, Kataoka J, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Longo F, Loparco F, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, McEnery J. E, Michelson P. F, Mignani R. P, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Orlando E, Ormes J. F, Paneque D, Parent D, Pelassa V, Pesce-Rollins M, Pierbattista M, Piron F, Pohl M, Porter T. A, Raino S, Rando R, Razzano M, Reimer O, Reposeur T, Ritz S, Romani R. W, Roth M, Sadrozinski H. F. -W, Parkinson P, M. Saz, Sgro C, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. G, Thayer J. B, Thompson D. J, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Troja E, Uchiyama Y, Vandenbroucke J, Vasileiou V, Vianello G, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yamamoto H, Yamazaki R, Yang Z, Ziegler M

ASTROPHYSICAL JOURNAL 734 ( 1 ) 2011年06月 [査読有り]

DOI

Scopus

234

被引用数

(Scopus)
Fermi gamma-ray space telescope observations of the gamma-ray outburst from 3C454.3 in November 2010

A. A. Abdo, M. Ackermann, M. Ajello, A. Allafort, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Conrad, S. Cutini, F. D'Ammando, A. De Angelis, F. De Palma, C. D. Dermer, S. W. Digel, E. Do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, L. Escande, C. Favuzzi, S. J. Fegan, E. C. Ferrara, P. Fortin, Y. Fukazawa, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, J. E. Grove, S. Guiriec, D. Hadasch, M. Hayashida, E. Hays, D. Horan, R. Itoh, G. Jóhannesson, A. S. Johnson, T. Kamae, H. Katagiri, J. Kataoka, J. Knödlseder, M. Kuss, J. Lande, S. Larsson, L. Latronico, S. H. Lee, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. N. Mazziotta, W. McConville, J. E. McEnery, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, M. Naumann-Godo, S. Nishino

Astrophysical Journal Letters 733 ( 2 PART 2 ) 2011年06月

　概要を見る

The flat-spectrum radio quasar 3C454.3 underwent an extraordinary 5 day γ-ray outburst in 2010 November when the daily flux measured with the Fermi Large Area Telescope (LAT) at photon energies E > 100MeV reached (66 2) × 10-6 photons cm-2 s-1. This is a factor of three higher than its previous maximum flux recorded in 2009 December and ≳ 5 times brighter than the Vela pulsar, which is normally the brightest source in the γ-ray sky. The 3hr peak flux was (85 5)×10-6 photons cm-2 s-1, corresponding to an apparent isotropic luminosity of (2.1 0.2)×1050 erg s-1, the highest ever recorded for a blazar. In this Letter, we investigate the features of this exceptional event in the γ-ray band of the Fermi-LAT. In contrast to previous flares of the same source observed with the Fermi-LAT, clear spectral changes are observed during the flare. © 2011. The American Astronomical Society. All rights reserved.

DOI

Scopus

177

被引用数

(Scopus)
Development of a large-area monolithic 4 x 4 MPPC array for a future PET scanner employing pixelized Ce:LYSO and Pr:LuAG crystals

T. Kato, J. Kataoka, T. Nakamori, T. Miura, H. Matsuda, K. Sato, Y. Ishikawa, K. Yamamura, N. Kawabata, H. Ikeda, G. Sato, K. Kamada

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 638 ( 1 ) 83 - 91 2011年05月 [査読有り]

　概要を見る

We have developed a new type of large-area monolithic Multi-Pixel Photon Counter (MPPC) array consisting of a 4 x 4 matrix of 3 x 3 mm(2) pixels. Each pixel comprises 3600 Geiger mode avalanche photodiodes (APDs) that achieve an average gain of 9.68 x 10(5) at 71.9 V at 0 degrees C with variations of only +/- 7.2% over 4 x 4 pixels. Excellent uniformity was also obtained for photon detection efficiencies (PDE) of +/- 6.4%, whilst dark count rates at the single photoelectron (1 p.e.) level amounted to similar or equal to 2 Mcps/pixel, measured at 0 degrees C. As the first step toward using the device in scintillation photon detectors, we fabricated a prototype gamma-ray camera consisting of an MPPC array optically coupled with a scintillator matrix, namely a 4 x 4 array of 3 x 3 x 10 mm(3) crystals. Specifically, we tested the performance with Ce-doped (Lu, Y)(2)(SiO(4))O (Ce:LYSO), Pr-doped Lu(3)Al(5)O(12) (Pr:LuAG) and "surface coated" Pr:LuAG (Pr:LuAG (WES)) matrices whereby the emission peak of Pr:LuAG was shifted from 310 to 420 nm via a wavelength shifter (WLS). Average energy resolutions of 13.83%, 14.70% and 13.96% (FWHM) were obtained for 662 keV gamma-rays, as measured at 0 degrees C with Ce:LYSO, Pr:LuAG and Pr:LuAG (WLS) scintillator matrices, respectively. We confirmed that the effective PDE for Pr:LuAG (WLS) had improved by more than 30% compared to original, non-coated Pr:LuAG matrix. These results suggest that a large-area monolithic MPPC array developed here could be promising for future medical imaging, particularly in positron emission tomography (PET). (C) 2011 Elsevier B.V. All rights reserved.

DOI

Scopus

41

被引用数

(Scopus)
MULTI-WAVELENGTH OBSERVATIONS OF THE FLARING GAMMA-RAY BLAZAR 3C 66A IN 2008 OCTOBER (vol 726, pg 43, 2011)

ASTROPHYSICAL JOURNAL 731 ( 1 ) 2011年04月 [査読有り]

DOI

Scopus

2

被引用数

(Scopus)
THE FIRST FERMI MULTIFREQUENCY CAMPAIGN ON BL LACERTAE: CHARACTERIZING THE LOW-ACTIVITY STATE OF THE EPONYMOUS BLAZAR

Abdo A. A, Ackermann M, Ajello M, Antolini E, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Cannon A, Caraveo P. A, Carrigan S, Casandjian J. M, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Costamante L, Cutini S, Dermer C. D, de Palma F, Donato D, do Couto e, Silva E, Drell P. S, Dubois R, Escande L, Favuzzi C, Fegan S. J, Finke J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Guiriec S, Hadasch D, Hayashida M, Hays E, Hughes R. E, Itoh R, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Larsson S, Latronico L, Lee S. -H, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nishino S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Ritz S, Roth M, Sadrozinski H. F. -W, Sanchez D, Sander A, Schinzel F. K, Sgro C, Siskind E. J, Smith P. D, Sokolovsky K. V, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uehara T, Usher T. L, Vandenbroucke J, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wallace E, Wang P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M, Berdyugin A, Boettcher M, Carraminana A, Carrasco L, de la Fuente E, Diltz C, Hovatta T, Kadenius V, Kovalev Y. Y, Lahteenmaki A, Lindfors E, Marscher A. P, Nilsson K, Pereira D, Reinthal R, Roustazadeh P, Savolainen T, Sillanpaa A, Takalo L. O, Tornikoski M

ASTROPHYSICAL JOURNAL 730 ( 2 ) 2011年04月 [査読有り]

DOI

Scopus

53

被引用数

(Scopus)
Searching for X-ray counterparts of Fermi Gamma-ray pulsars in Suzaku observations

Aoki, Y, Enomoto, T, Yatsu, Y, Kawai, N, Nakamori, T, Kataoka, J, Saz Parkinson, P

Proceedings of the International Astronomical Union 7 ( S279 ) 317 - 318 2011年04月

DOI

Scopus

1

被引用数

(Scopus)
DETECTION OF A SPECTRAL BREAK IN THE EXTRA HARD COMPONENT OF GRB 090926A

Ackermann M, Ajello M, Asano K, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bhat P. N, Bissaldi E, Blandford R. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Briggs M. S, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cecchi C, Celik O, Chaplin V, Charles E, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Connaughton V, Conrad J, Cutini S, Dermer C. D, De Angelis A, De Palma F, Dingus B. L, Silva E. Do Couto E, Drell P. S, Dubois R, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Goldstein A, Granot J, Greiner J, Grenier I. A, Grove J. E, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashi K, Hayashida M, Hays E, Horan D, Hughes R. E, Itoh R, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kippen R. M, Knoedlseder J, Kocevski D, Kouveliotou C, Kuss M, Lande J, Latronico L, Lee S. -H, Garde M. Llena, Longo F, Loparco F, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, McBreen S, McEnery J. E, McGlynn S, Meegan C, Mehault J, Meszaros P, Michelson P. F, Mizuno T, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakajima H, Nakamori T, Naumann-Godo M, Nishino S, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paciesas W. S, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Petrosian V, Piron F, Porter T. A, Preece R, Racusin J. L, Raino S, Rando R, Rau A, Razzano M, Razzaque S, Reimer A, Reimer O, Reposeur T, Reyes L. C, Ripken J, Ritz S, Roth M, Ryde F, Sadrozinski H. F. -W, Sander A, Scargle J. D, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Tanaka T, Tanaka Y, Thayer J. B, Thayer J. G, Tibaldo L, Tierney D, Toma K, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Uehara T, Usher T. L, Vandenbroucke J, van der Horst A. J, Vasileiou V, Vilchez N, Vitale V, von Kienlin A, Waite A. P, Wang P, Wilson-Hodge C, Winer B. L, Wood K. S, Wu X. F, Yamazaki R, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 729 ( 2 ) 2011年03月 [査読有り]

DOI

Scopus

194

被引用数

(Scopus)
THE FIRST FERMI LARGE AREA TELESCOPE CATALOG OF GAMMA-RAY PULSARS (vol 187, pg 460, 2010)

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, M. G. Baring, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, F. Camilo, P. A. Caraveo, J. M. Casandjian, C. Cecchi, Oe. Celik, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, I. Cognard, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, R. Corbet, S. Cutini, P. R. den Hartog, C. D. Dermer, A. de Angelis, A. de Luca, F. de Palma, S. W. Digel, M. Dormody, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Espinoza, C. Farnier, C. Favuzzi, S. J. Fegan, E. C. Ferrara, W. B. Focke, P. Fortin, M. Frailis, P. C. C. Freire, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, G. Giavitto, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, T. Glanzman, G. Godfrey, E. V. Gotthelf, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, C. Gwon, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, R. E. Hughes, M. S. Jackson, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, S. Johnston, T. Kamae, G. Kanbach, V. M. Kaspi, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, M. L. Kocian, M. Kramer, M. Kuss, J. Lande, L. Latronico, M. Lemoine-Goumard, M. Livingstone, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, A. G. Lyne, G. M. Madejski, A. Makeev, R. N. Manchester, M. Marelli, M. N. Mazziotta, W. McConville, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, T. Mineo, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, P. L. Nolan, J. P. Norris, A. Noutsos, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, R. Rando, S. M. Ransom, P. S. Ray, M. Razzano, N. Rea, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, B. W. Stappers, J. -L. Starck, E. Striani, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, G. Theureau, D. J. Thompson, S. E. Thorsett, L. Tibaldo, O. Tibolla, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, A. Van Etten, V. Vasileiou, C. Venter, N. Vilchez, V. Vitale, A. P. Waite, P. Wang, N. Wang, K. Watters, P. Weltevrede, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES 193 ( 1 ) 460 - 494 2011年03月 [査読有り]

DOI

Scopus

5

被引用数

(Scopus)
27pGS-11 ASTRO-H衛星硬X線・軟ガンマ線検出器アクティブシールドの構造設計(27pGS X線(ASTRO-Hなど),宇宙線・宇宙物理領域)

中島健太, 中野俊男, 中澤知洋, 牧島一夫, 花畑義隆, 深沢泰司, 山岡和貴, 田島宏康, 片岡淳, 高橋弘充, 水野恒史, 大野雅功, 国分紀秀, 高橋忠幸, 渡辺伸, 田代信, 寺田幸功, HXI, SGDチーム

日本物理学会講演概要集 66 ( 1 ) 122 - 122 2011年03月

CiNii
28aGP-6 APD/MPPCを用いた高解像度γ線イメージセンサー(28aGP 素粒子実験領域シンポジウム:先端的放射線検出器開発とその応用で拓かれる未来,素粒子実験領域)

片岡淳

日本物理学会講演概要集 66 ( 1 ) 36 - 36 2011年03月

CiNii
UNRAVELING THE NATURE OF UNIDENTIFIED HIGH GALACTIC LATITUDE FERMI/LAT GAMMA-RAY SOURCES WITH SUZAKU

K. Maeda, J. Kataoka, T. Nakamori, L. Stawarz, R. Makiya, T. Totani, C. C. Cheung, D. Donato, N. Gehrels, P. Saz Parkinson, Y. Kanai, N. Kawai, Y. Tanaka, R. Sato, T. Takahashi, Y. Takahashi

ASTROPHYSICAL JOURNAL 729 ( 2 ) 103 - 116 2011年03月 [査読有り]

　概要を見る

Here we report on the results of deep X-ray follow-up observations of four unidentified gamma-ray sources detected by the Fermi/LAT instrument at high Galactic latitudes using the X-ray Imaging Spectrometers on board the Suzaku satellite. All of the studied objects were detected with high significance during the first three months of Fermi/LAT operation and subsequently better localized in the first Fermi/LAT catalog (1FGL). For some of them, possible associations with pulsars and active galaxies have subsequently been discussed, and our observations provide an important contribution to this debate. In particular, a bright X-ray point source has been found within the 95% confidence error circle of 1FGL J1231.1-1410. The X-ray spectrum of the discovered Suzaku counterpart of 1FGL J1231.1-1410 is well fitted by a blackbody with an additional power-law component. This supports the recently claimed identification of this source with a millisecond pulsar PSR J1231-1411. For the remaining three Fermi objects, on the other hand, the X-ray observations performed are less conclusive. In the case of 1FGL J1311.7-3429, two bright X-ray point sources were found within the LAT 95% error circle. Even though the X-ray spectral and variability properties for these sources were robustly assessed, their physical nature and relationship with the gamma-ray source remain uncertain. Similarly, we found several weak X-ray sources in the field of 1FGL J1333.2+5056, one coinciding with the high-redshift blazar CLASS J1333+5057. We argue that the available data are consistent with the physical association between these two objects, although the large positional uncertainty of the gamma-ray source hinders a robust identification. Finally, we have detected an X-ray point source in the vicinity of 1FGL J2017.3+0603. This Fermi object was recently suggested to be associated with a newly discovered millisecond radio pulsar PSR J2017+0603, because of the spatial coincidence and the detection of the gamma-ray pulsations in the light curve of 1FGL J2017.3+0603. Interestingly, we have detected the X-ray counterpart of the high-redshift blazar CLASS J2017+0603, located within the error circle of the gamma-ray source, while we were only able to determine an X-ray flux upper limit at the pulsar position. All in all, our studies indicate that while a significant fraction of unidentified high Galactic latitude gamma-ray sources is related to the pulsar and blazar phenomena, associations with other classes of astrophysical objects are still valid options.

DOI

Scopus

16

被引用数

(Scopus)
RADIO AND gamma-RAY CONSTRAINTS ON THE EMISSION GEOMETRY AND BIRTHPLACE OF PSR J2043+2740

Noutsos A, Abdo A. A, Ackermann M, Ajello M, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Busetto G, Caliandro G. A, Cameron R. A, Camilo F, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Chaty S, Chekhtman A, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Colafrancesco S, Cutini S, Dermer C. D, de Palma F, Drell P. S, Dumora D, Ea C. M, Favuzzi C, Ferrara E. C, Focke W. B, Frailis M, Freire P. C. C, Fukazawa Y, Funk S, Fusco P, Gargano F, Germani S, Giglietto N, Giordano F, Giroletti M, Godfrey G, Grandi P, Grenier I. A, Grove J. E, Guillemot L, Guiriec S, Harding A. K, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Johnston S, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kramer M, Kuss M, Lande J, Lee S-H, Longo F, Loparco F, Lovellette M. N, Lubrano P, Lyne A. G, Makeev A, Marelli M, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Nolan P. L, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Panetta J. H, Parent D, Pelassa V, Pepe M, Persic M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Ray P. S, Razzano M, Reimer A, Reimer O, Reposeur T, Romani R. W, Sadrozinski H. F-W, Sander A, Parkinson P, M. Saz, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Stappers B. W, Strickman M. S, Suson D. J, Takahashi H, Tanaka T, Theureau G, Thompson D. J, Thorsett S. E, Tibolla O, Torres D. F, Tramacere A, Usher T. L, Vandenbroucke J, Vianello G, Vilchez N, Villata M, Vitale V, von Kienlin A, Waite A. P, Wang P, Watters K, Weltevrede P, Winer B. L, Wood K. S, Ziegler M

ASTROPHYSICAL JOURNAL 728 ( 2 ) 2011年02月 [査読有り]

DOI

Scopus

5

被引用数

(Scopus)
Gamma-Ray Flares from the Crab Nebula

Abdo A. A, Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Br, dt T. J, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Cannon A, Caraveo P. A, Casandjian J. M, Celik O, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Costamante L, Cutini S, D'Ammando F, Dermer C. D, de Angelis A, de Luca A, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Dubois R, Dumora D, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashi K, Hayashida M, Hays E, Horan D, Itoh R, Johannesson G, Johnson A. S, Johnson T. J, Khangulyan D, Kamae T, Katagiri H, Kataoka J, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Longo F, Loparco F, Lubrano P, Madejski G. M, Makeev A, Marelli M, Mazziotta M. N, McEnery J. E, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Ormes J. F, Ozaki M, Paneque D, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Pierbattista M, Piron F, Porter T. A, Raino S, Rando R, Ray P. S, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Romani R. W, Sadrozinski H. F. -W, Sanchez D, Parkinson P, M. Saz, Scargle J. D, Schalk T. L, Sgro C, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Troja E, Uchiyama Y, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Wang P, Wood K. S, Yang Z, Ziegler M

SCIENCE 331 ( 6018 ) 739 - 742 2011年02月 [査読有り]

DOI

Scopus

347

被引用数

(Scopus)
INSIGHTS INTO THE HIGH-ENERGY gamma-RAY EMISSION OF MARKARIAN 501 FROM EXTENSIVE MULTIFREQUENCY OBSERVATIONS IN THE FERMI ERA

ASTROPHYSICAL JOURNAL 727 ( 2 ) 2011年02月 [査読有り]

DOI

Scopus

158

被引用数

(Scopus)
Searching for the most distant blazars with the Fermi Gamma-ray Space Telescope

Yoshiyuki Inoue, Susumu Inoue, Masakazu A. R. Kobayashi, Tomonori Totani, Jun Kataoka, Rie Sato

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 411 ( 1 ) 464 - 468 2011年02月 [査読有り]

　概要を見る

We investigate the prospects for discovering blazars at very high redshifts (z greater than or similar to 3-6) with the Fermi Gamma-ray Space Telescope (hereinafter Fermi), employing a model for the evolving gamma-ray luminosity function (GLF) of the blazar population. Our previous GLF model is used as a basis, which features luminosity-dependent density evolution implied from X-ray data on active galactic nuclei as well as the blazar sequence paradigm for their spectral energy distribution, and which is consistent with the Energetic Gamma-Ray Experiment Telescope and the current Fermi observations of blazars. Here, we augment the high-redshift evolution of this model by utilizing the luminosity function of quasars from the Sloan Digital Sky Survey, which is well-constrained up to z similar to 5. We find that the Fermi may discover a few blazars up to z similar to 6 in the entire sky during its 5-yr survey. We further discuss how such high-redshift blazar candidates may be efficiently selected in the future Fermi data.

DOI

Scopus

14

被引用数

(Scopus)
Development of the small satellite “Tsubame”

Toizumi, T, Enomoto, Yatsu, Y, Nakamori, T, Kawai, N, Ishizuka, K, Morishita, H, Akiyama, K, Kisa, N, Inagawa, S, Kawakubo, M, Nishida, J, Mizunuma, S, Matsunaga, S, Kataoka, J

Physica E 43 ( 3 ) 685 - 688 2011年01月 [査読有り]

DOI

Scopus

8

被引用数

(Scopus)
CONSTRAINTS ON THE COSMIC-RAY DENSITY GRADIENT BEYOND THE SOLAR CIRCLE FROM FERMI gamma-RAY OBSERVATIONS OF THE THIRD GALACTIC QUADRANT

Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgla, A. W, Brandt T. J, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Dermer C. D, de Palma F, Digel S. W, Drell P. S, Dubois R, Favuzzi C, Ferrara E. C, Focke W. B, Fukazawa Y, Funk S, Fusco P, Gargano F, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashi K, Hayashida M, Hughes R. E, Itoh R, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Garde M. Llena, Longo F, Loparco F, Lovellette M. N, Lubrano P, Makeev A, Martin P, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Nishino S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Ripken J, Sada T, Sadrozinski H. F. -W, Sgro C, Siskind E. J, Spandre G, Spinelli P, Strickman M. S, Strong A. W, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thompson D. J, Tibaldo L, Torres D. F, Tramacere A, Uchiyama Y, Uehara T, Usher T. L, Vandenbroucke J, Vasileiou V, Vilchez N, Vitale V, Vladimirov A. E, Waite A. P, Wang P, Wood K. S, Yang Z, Ziegler M

ASTROPHYSICAL JOURNAL 726 ( 2 ) 2011年01月 [査読有り]

DOI

Scopus

35

被引用数

(Scopus)
Time over Threshold Based Digital Animal PET (TODPET)

K. Shimazoe, Y. Wang, H. Takahashi, K. Kamada, M. Yoshino, J. Kataoka, Y. Yamaya, T. Yanagida, A. Yoshikawa, K. Kumagai

2011 IEEE NUCLEAR SCIENCE SYMPOSIUM AND MEDICAL IMAGING CONFERENCE (NSS/MIC) 3267 - 3271 2011年 [査読有り]

　概要を見る

We have developed Time over Threshold (ToT) based Pr:LuAG-APD PET (TODPET) tomograph with a mixed signal front-end. The tomograph consists of 8 block detectors, each of which is composed of a 12 x 12 array of 2 x 2 x 10mm(3) Pr:LuAG crystals individually coupled with 12 x 12 UV-enhanced APD arrays. The APDs are individually read out with a custom-designed Time over Threshold ASIC and FPGA readout system. Developed PET tomograph has the energy resolution of 10% and the time resolution of 4.2ns. The 1.76mm spatial resolution (FWHM) is achieved for the first result.
Simultaneous multi-wavelength campaign on PKS 2005-489 in a high state

A. Abramowski, F. Acero, F. Aharonian, A. G. Akhperjanian, G. Anton, A. Barnacka, U. Barres De Almeida, A. R. Bazer-Bachi, Y. Becherini, J. Becker, B. Behera, K. Bernlöhr, A. Bochow, C. Boisson, J. Bolmont, P. Bordas, V. Borrel, J. Brucker, F. Brun, P. Brun, T. Bulik, I. Büsching, S. Casanova, M. Cerruti, P. M. Chadwick, A. Charbonnier, R. C.G. Chaves, A. Cheesebrough, L. M. Chounet, A. C. Clapson, G. Coignet, J. Conrad, M. Dalton, M. K. Daniel, I. D. Davids, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Ataï, W. Domainko, L. O. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, P. Eger, P. Espigat, L. Fallon, C. Farnier, S. Fegan, F. Feinstein, M. V. Fernandes, A. Fiasson, G. Fontaine, A. Förster, M. Füßling, S. Gabici, Y. A. Gallant, H. Gast, L. Gérard, D. Gerbig, B. Giebels, J. F. Glicenstein, B. Glück, P. Goret, D. Göring, J. D. Hague, D. Hampf, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, P. Hofverberg, D. Horns, A. Jacholkowska, O. C. De Jager, C. Jahn, M. Jamrozy, I. Jung, M. A. Kastendieck, K. Katarzyński, U. Katz, S. Kaufmann, D. Keogh, M. Kerschhaggl, D. Khangulyan, B. Khélifi, D. Klochkov, W. Kluåniak, T. Kneiske, Nu Komin, K. Kosack, R. Kossakowski, H. Laffon, G. Lamanna

Astronomy and Astrophysics 533 2011年

　概要を見る

The high-frequency peaked BL Lac object PKS 2005-489 was the target of a multi-wavelength campaign with simultaneous observations in the TeV γ-ray (H.E.S.S.), GeV γ-ray (Fermi/LAT), X-ray (RXTE, Swift), UV (Swift) and optical (ATOM, Swift) bands. This campaign was carried out during a high flux state in the synchrotron regime. The flux in the optical and X-ray bands reached the level of the historical maxima. The hard GeV spectrum observed with Fermi/LAT connects well to the very high energy (VHE, E > 100 GeV) spectrum measured with H.E.S.S. © 2011 ESO.

DOI

Scopus

15

被引用数

(Scopus)
Experimental demonstration of single-photon detection using InGaAs avalanche photodiode operated in sub-Geiger mode

Kenji Tsujino, Yoshito Miyamoto, Jun Kataoka, Akihisa Tomita

AIP Conference Proceedings 1363 351 - 354 2011年

　概要を見る

The avalanche photodiode (APD) is a promising device for single-photon detection. In this study, we operated an InGaAs APD in the sub-Geiger mode. In this mode, a gate pulse is not needed; therefore, we can detect photons with asynchronous timing. The detection efficiency and the dark count rate were 2.2% and 7900 counts per second (cps), respectively. © 2011 American Institute of Physics.

DOI

Scopus

3

被引用数

(Scopus)
Scintillation properties of transparent Lu3Al5O12 (LuAG) ceramics doped with different concentrations of Pr3+

Takayuki Yanagida, Akihiro Fukabori, Yutaka Fujimoto, Akio Ikesue, Kei Kamada, Jun Kataoka, Yuui Yokota, Akira Yoshikawa, Valery Chani

PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 8, NO 1 8 ( 1 ) 140 - 143 2011年 [査読有り]

　概要を見る

Transparent ceramics of Pr-doped (0.2 mol%, 0.6 mol%, 1 mol%, and 2 mol%) Lu3Al5O12 (LuAG) scintillators produced by the sintering method are discussed. These materials were cut to the specimens with physical dimensions of 5 x 5 x 2 mm(3). Similar size specimens were also prepared from Czochralski grown Pr:LuAG single crystals to compare scintillation properties. Their transmittance and radio luminescence spectra were evaluated. All specimens were highly transparent in wavelength range above 300 nm, and intense Pr3+ 5d-4f emission was detected around 310 and 370 nm under excitation with X-ray. Under Cs-137 gamma-ray is irradiation, 2 keV photoabsorption peaks were also clearly observed in each sample. The Pr 0.6 mol% doped LuAG ceramics demonstrated highest light yield achievable among the ceramics, and it was half of that observed in the single crystals. Under pulse X-ray excitation, the decay time constants became faster when Pr concentration increased, and. the fastest decay (similar to 5.7 ns time constant) was noticed in the 2 mol% doped ceramic. (c) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

DOI

Scopus

35

被引用数

(Scopus)
FERMI-LAT SEARCH FOR PULSAR WIND NEBULAE AROUND GAMMA-RAY PULSARS

Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Camilo F, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Conrad J, Dermer C. D, de Angelis A, de Luca A, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Favuzzi C, Focke W. B, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashi K, Hays E, Hobbs G, Hughes R. E, Johannesson G, Johnson A. S, Johnson W. N, Johnston S, Kamae T, Katagiri H, Kataoka J, Keith M, Kerr M, Knoedlseder J, Kramer M, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Longo F, Loparco F, Lovellette M. N, Lubrano P, Lyne A. G, Makeev A, Marelli M, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nolan P. L, Noutsos A, Nuss E, Ohsugi T, Okumura A, Ormes J. F, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Ransom S. M, Ray P. S, Razzano M, Rea N, Reimer A, Reimer O, Reposeur T, Ripken J, Ritz S, Romani R. W, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Theureau G, Thompson D. J, Thorsett S. E, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Uehara T, Usher T. L, Vandenbroucke J, Van Etten A, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Weltevrede P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 726 ( 1 ) 2011年01月 [査読有り]

DOI

Scopus

26

被引用数

(Scopus)
MULTI-WAVELENGTH OBSERVATIONS OF THE FLARING GAMMA-RAY BLAZAR 3C 66A IN 2008 OCTOBER

ASTROPHYSICAL JOURNAL 726 ( 1 ) 2011年01月 [査読有り]

DOI

Scopus

62

被引用数

(Scopus)
Search for gamma-ray emission from magnetars with the Fermi large area telescope

A. A. Abdo, M. Ackermann, M. Ajello, A. Allafort, L. Baldini, J. Ballet, G. Barbiellini, M. G. Baring, D. Bastieri, R. Bellazzini, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, C. Cecchi, Ö Çelik, S. Chaty, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Conrad, P. R. Den Hartog, C. D. Dermer, A. De Angelis, F. De Palma, R. Dib, M. Dormody, E. Do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, T. Enoto, C. Favuzzi, M. Frailis, P. Fusco, F. Gargano, N. Gehrels, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, S. Guiriec, D. Hadasch, Y. Hanabata, A. K. Harding, E. Hays, G. L. Israel, G. Jóhannesson, A. S. Johnson, V. M. Kaspi, H. Katagiri, J. Kataoka, J. Knödlseder, M. Kuss, J. Lande, S. H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, A. Makeev, M. Marelli, M. N. Mazziotta, J. E. McEnery, J. Mehault, P. F. Michelson, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, M. Naumann-Godo, P. L. Nolan, E. Nuss, T. Ohsugi, A. Okumura, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, D. Parent, M. Pepe

Astrophysical Journal Letters 725 ( 1 PART 2 ) 2010年12月

　概要を見る

We report on the search for 0.1-10GeV emission from magnetars in 17months of Fermi LargeAreaTelescope (LAT) observations. No significant evidence for gamma-ray emission from any of the currently known magnetars is found. The most stringent upper limits to date on their persistent emission in the Fermi energy range are estimated between ∼10-12 and 10-10 erg s-1 cm-2, depending on the source.We also searched for gamma-ray pulsations and possible outbursts, also with no significant detection. The upper limits derived support the presence of a cutoff at an energy below a few MeV in the persistent emission of magnetars. They also show the likely need for a revision of current models of outer-gap emission from stronglymagnetized pulsars, which, in some realizations, predict detectableGeV emission frommagnetars at flux levels exceeding the upper limits identified here using the Fermi-LAT observations. © 2010. The American Astronomical Society. All rights reserved.

DOI

Scopus

44

被引用数

(Scopus)
A thermal-neutron detector with a phoswich system of LiCaAlF<inf>6</inf>and BGO crystal scintillators onboard PoGOLite

H. Takahashi, M. Yonetani, M. Matsuoka, T. Mizuno, Y. Fukazawa, T. Yanagida, Y. Fujimoto, Y. Yokota, A. Yoshikawa, N. Kawaguchi, S. Ishizu, K. Fukuda, T. Suyama, K. Watanabe, H. Tajima, Y. Kanai, N. Kawai, J. Kataoka, J. Katsuta, T. Takahashi, S. Gunji, M. Axelsson, M. Jackson, M. Kiss, W. Klamra, M. Kole, S. Larsson, P. Mallol, M. Pearce, F. Ryde, S. Rydstrom, G. Olofsson, H. G. Floren, T. Kamae, G. Madejski, G. Varner

IEEE Nuclear Science Symposium Conference Record 32 - 37 2010年12月

　概要を見る

To measure the flux of atmospheric neutrons and study the neutron contribution to the background of the main detector of the PoGOLite (Polarized Gamma-ray Observer) balloon-borne experiment, a thermal-neutron detector with a phoswich system of LiCaAlF6(Eu) and BGO crystal scintillators is developed. The performance to separate thermal-neutron events from those of gamma-rays and charged particles is validated with252Cf on ground. The detector is attached to the PoGOLite instrument and is launched in 2011 from the Esrange facility in the North of Sweden. Although the emission wavelength of the LiCaAlF6(Ce) is 300 nm and overlaps with the absorption wavelength of the BGO, the phoswich capability of the LiCaAlF6(Ce) with the BGO is also confirmed with installing a waveform shifter. © 2010 IEEE.

DOI

Scopus

7

被引用数

(Scopus)
Small Satellite "TSUBAME" for Polarimetry of Gamma-ray Burst

Enomoto, T, Kawakami, K, Tokoyoda, K, Toizumi, T, Yatsu, Y, Kawai, N, Matsunaga, S, Nakamori, T, Kataoka, J, Kubo, S

Proc. of 4th MAXI Workshop 65 - 4pp 2010年12月
A NOVEL APPROACH IN CONSTRAINING ELECTRON SPECTRA IN BLAZAR JETS: THE CASE OF Markarian 421

Masayoshi Ushio, Lukasz Stawarz, Tadayuki Takahashi, David Paneque, Grzegorz Madejski, Masaaki Hayashida, Jun Kataoka, Yasuyuki T. Tanaka, Takaaki Tanaka, Michal Ostrowski

ASTROPHYSICAL JOURNAL 724 ( 2 ) 1509 - 1516 2010年12月 [査読有り]

　概要を見る

We report results from the observations of the well-studied TeV blazar Mrk 421 with the Swift and the Suzaku satellites in 2008 December. During the observation, Mrk 421 was found in a relatively low activity state, with the corresponding 2-10 keV flux of 3 x 10(-10) erg s(-1) cm(-2). For the purpose of robustly constraining the UV-to-X-ray emission continuum we selected only the data corresponding to truly simultaneous time intervals between Swift and Suzaku, allowing us to obtain a good-quality, broadband spectrum despite a modest length (0.6 ks) exposure. We analyzed the spectrum with the parametric forward-fitting SYNCHROTRON model implemented in XSPEC assuming two different representations of the underlying electron energy distribution, both well motivated by the current particle acceleration models: a power-law distribution above the minimum energy gamma(min) with an exponential cutoff at the maximum energy gamma(max), and a modified ultra-relativistic Maxwellian with an equilibrium energy gamma(eq). We found that the latter implies unlikely physical conditions within the blazar zone of Mrk 421. On the other hand, the exponentially moderated power-law electron distribution gives two possible sets of the model parameters: (1) flat spectrum dN'(e)/d gamma proportional to gamma(-1.91) with low minimum electron energy gamma(min) < 10(3), and (2) steep spectrum proportional to gamma(-2.77) with high minimum electron energy gamma(min) similar or equal to 2 x 10(4). We discuss different interpretations of both possibilities in the context of a diffusive acceleration of electrons at relativistic, sub- or superluminal shocks. We also comment on exactly how the gamma-ray data can be used to discriminate between the different proposed scenarios.

DOI

Scopus

21

被引用数

(Scopus)
A population of gamma-ray emitting globular clusters seen with the Fermi Large Area Telescope

A. A. Abdo, M. Ackermann, M. Ajello, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, R. Bellazzini, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, T. J. Brandt, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, S. Carrigan, J. M. Casandjian, E. Charles, S. Chaty, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, M. E. Decesar, C. D. Dermer, F. De Palma, S. W. Digel, E. Do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, C. Favuzzi, P. Fortin, M. Frailis, Y. Fukazawa, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, I. Grenier, M. H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, D. Hadasch, A. K. Harding, E. Hays, P. Jean, G. Jóhannesson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, S. H. Lee, M. Lemoine-Goumard, M. Llena Garde, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, A. Makeev, M. N. Mazziotta, P. F. Michelson, W. Mitthumsiri, T. Mizuno, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, M. Naumann-Godo, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, B. Pancrazi

Astronomy and Astrophysics 524 ( 3 ) 2010年11月

　概要を見る

Context. Globular clusters with their large populations of millisecond pulsars (MSPs) are believed to be potential emitters of high-energy gamma-ray emission. The observation of this emission provides a powerful tool to assess the millisecond pulsar population of a cluster, is essential for understanding the importance of binary systems for the evolution of globular clusters, and provides complementary insights into magnetospheric emission processes. Aims. Our goal is to constrain the millisecond pulsar populations in globular clusters from analysis of gamma-ray observations. Methods. We use 546 days of continuous sky-survey observations obtained with the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope to study the gamma-ray emission towards 13 globular clusters. Results. Steady point-like high-energy gamma-ray emission has been significantly detected towards 8 globular clusters. Five of them (47 Tucanae, Omega Cen, NGC 6388, Terzan 5, and M 28) show hard spectral power indices (0.7 < Γ <1.4) and clear evidence for an exponential cut-off in the range 1.0-2.6 GeV, which is the characteristic signature of magnetospheric emission from MSPs. Three of them (M 62, NGC 6440 and NGC 6652) also show hard spectral indices (1.0 < Γ < 1.7), however the presence of an exponential cut-off can not be unambiguously established. Three of them (Omega Cen, NGC 6388, NGC 6652) have no known radio or X-ray MSPs yet still exhibit MSP spectral properties. From the observed gamma-ray luminosities, we estimate the total number of MSPs that is expected to be present in these globular clusters. We show that our estimates of the MSP population correlate with the stellar encounter rate and we estimate 2600-4700 MSPs in Galactic globular clusters, commensurate with previous estimates. Conclusions. The observation of high-energy gamma-ray emission from globular clusters thus provides a reliable independent method to assess their millisecond pulsar populations. © ESO, 2010. © 2010 ESO.

DOI

Scopus

143

被引用数

(Scopus)
Fermi LAT observations of cosmic-ray electrons from 7 GeV to 1 TeV

Ackermann M, Ajello M, Atwood W. B, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellardi F, Bellazzini R, Belli F, Berenji B, Blandford R. D, Bloom E. D, Bogart J. R, Bonamente E, Borgla, A. W, Brandt T. J, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Burnett T. H, Busetto G, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carlson P, Carrigan S, Casandjian J. M, Ceccanti M, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Cillis A. N, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Corbet R, DeKlotz M, Dermer C. D, de Angelis A, de Palma F, Digel S. W, Di Bernardo G, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Dubois R, Fabiani D, Favuzzi C, Fegan S. J, Fortin P, Fukazawa Y, Funk S, Fusco P, Gaggero D, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grasso D, Grenier I. A, Grondin M. -H, Grove J. E, Guiriec S, Gustafsson M, Hadasch D, Harding A. K, Hayashida M, Hays E, Horan D, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Minuti M, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Petrosian V, Pinchera M, Piron F, Porter T. A, Profumo S, Raino S, Rando R, Rapposelli E, Razzano M, Reimer A, Reimer O, Reposeur T, Ripken J, Ritz S, Rochester L. S, Romani R. W, Roth M, Sadrozinski H. F. -W, Saggini N, Sanchez D, Sander A, Sgro C, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Stawarz L, Stephens T. E, Strickman M. S, Strong A. W, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Turri M, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wallace E, Wang P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M

PHYSICAL REVIEW D 82 ( 9 ) 2010年11月 [査読有り]

DOI

Scopus

382

被引用数

(Scopus)
Searches for cosmic-ray electron anisotropies with the Fermi Large Area Telescope

Ackermann M, Ajello M, Atwood W. B, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cuoco A, Dermer C. D, de Angelis A, de Palma F, Digel S. W, Di Bernardo G, do Couto e, Silva E, Drell P. S, Dubois R, Favuzzi C, Fegan S. J, Focke W. B, Frailis M, Fukazawa Y, Funk S, Fusco P, Gaggero D, Gargano F, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grasso D, Grenier I. A, Grove J. E, Guiriec S, Gustafsson M, Hadasch D, Harding A. K, Hayashi K, Hays E, Hughes R. E, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nolan P. L, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Profumo S, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ripken J, Ritz S, Roth M, Sadrozinski H. F. -W, Sander A, Schalk T. L, Sgro C, Siegal-Gaskins J, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Strong A. W, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Zaharijas G, Ziegler M

PHYSICAL REVIEW D 82 ( 9 ) 2010年11月 [査読有り]

DOI

Scopus

103

被引用数

(Scopus)
Detection of the Small Magellanic Cloud in gamma-rays with Fermi /LAT

A. A. Abdo, M. Ackermann, M. Ajello, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, T. J. Brandt, J. Bregeon, A. Brez, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, S. Carrigan, J. M. Casandjian, C. Cecchi, Ö Çelik, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, C. D. Dermer, F. De Palma, S. W. Digel, E. Do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, C. Favuzzi, S. J. Fegan, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, J. E. Grove, S. Guiriec, D. Hadasch, A. K. Harding, M. Hayashida, E. Hays, D. Horan, R. E. Hughes, P. Jean, G. Jóhannesson, A. S. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, S. H. Lee, M. Lemoine-Goumard, M. Llena Garde, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, A. Makeev, P. Martin, M. N. Mazziotta, J. E. McEnery, P. F. Michelson, W. Mitthumsiri, T. Mizuno, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori

Astronomy and Astrophysics 523 ( 3 ) 2010年11月

　概要を見る

Context. The flux of gamma rays with energies greater than 100 MeV is dominated by diffuse emission coming from cosmic-rays (CRs) illuminating the interstellar medium (ISM) of our Galaxy through the processes of Bremsstrahlung, pion production and decay, and inverse-Compton scattering. The study of this diffuse emission provides insight into the origin and transport of cosmic rays. Aims.We searched for gamma-ray emission from the Small Magellanic Cloud (SMC) in order to derive constraints on the cosmic-ray population and transport in an external system with properties different from the Milky Way. Methods.We analysed the first 17 months of continuous all-sky observations by the Large Area Telescope (LAT) of the Fermi mission to determine the spatial distribution, flux and spectrum of the gamma-ray emission from the SMC. We also used past radio synchrotron observations of the SMC to study the population of CR electrons specifically. Results.We obtained the first detection of the SMC in high-energy gamma rays, with an integrated >100MeV flux of (3.7±0.7)×10-8 ph cm-2 s-1, with additional systematic uncertainty of ≤16%. The emission is steady and from an extended source ∼3. in size. It is not clearly correlated with the distribution of massive stars or neutral gas, nor with known pulsars or supernova remnants, but a certain correlation with supergiant shells is observed. Conclusions.The observed flux implies an upper limit on the average CR nuclei density in the SMC of ∼15% of the value measured locally in the Milky Way. The population of high-energy pulsars of the SMC may account for a substantial fraction of the gamma-ray flux, which would make the inferred CR nuclei density even lower. The average density of CR electrons derived from radio synchrotron observations is consistent with the same reduction factor but the uncertainties are large. From our current knowledge of the SMC, such a low CR density does not seem to be due to a lower rate of CR injection and rather indicates a smaller CR confinement volume characteristic size. © 2010 ESO.

DOI

Scopus

87

被引用数

(Scopus)
Fermi Large Area Telescope observations of Local Group galaxies: Detection of M 31 and search for M 33

A. A. Abdo, M. Ackermann, M. Ajello, A. Allafort, W. B. Atwood, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, T. J. Brandt, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, A. Cannon, P. A. Caraveo, J. M. Casandjian, C. Cecchi, Ö Çelik, E. Charles, A. Chekhtman, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, C. D. Dermer, A. De Angelis, F. De Palma, S. W. Digel, E. Do Couto E Silva, P. S. Drell, A. Drlica-Wagner, R. Dubois, C. Favuzzi, S. J. Fegan, P. Fortin, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, S. Guiriec, M. Gustafsson, D. Hadasch, A. K. Harding, K. Hayashi, M. Hayashida, E. Hays, S. E. Healey, P. Jean, G. Jóhannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, S. H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, P. Martin, M. N. Mazziotta, J. Mehault, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte

Astronomy and Astrophysics 523 ( 1 ) 2010年11月

　概要を見る

Context. Cosmic rays (CRs) can be studied through the galaxy-wide gamma-ray emission that they generate when propagating in the interstellar medium. The comparison of the diffuse signals from different systems may inform us about the key parameters in CR acceleration and transport. Aims. We aim to determine and compare the properties of the cosmic-ray-induced gamma-ray emission of several Local Group galaxies. Methods. We use 2 years of nearly continuous sky-survey observations obtained with the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope to search for gamma-ray emission from M 31 and M 33. We compare the results with those for the Large Magellanic Cloud, the Small Magellanic Cloud, the Milky Way, and the starburst galaxies M 82 and NGC 253. Results. We detect a gamma-ray signal at 5σ significance in the energy range 200 MeV-20 GeV that is consistent with originating from M 31. The integral photon flux above 100 MeV amounts to (9.1 ± 1.9stat ± 1.0) × 10-9 ph cm-2. We find no evidence for emission from M 33 and derive an upper limit on the photon flux >100 MeV of 5.1 × 10-9 ph cm-2-1 (2σ). Comparing these results to the properties of other Local Group galaxies, we find indications of a correlation between star formation rate and gamma-ray luminosity that also holds for the starburst galaxies. Conclusions. The gamma-ray luminosity of M 31 is about half that of the Milky Way, which implies that the ratio between the average CR densities in M 31 and the Milky Way amounts to ξ = 0.35 ± 0.25. The observed correlation between gamma-ray luminosity and star formation rate suggests that the flux of M 33 is not far below the current upper limit from the LAT observations. © 2010 ESO.

DOI

Scopus

117

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE CONSTRAINTS ON THE GAMMA-RAY OPACITY OF THE UNIVERSE

Abdo A. A, Ackermann M, Ajello M, Allafort A, Atwood W. B, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Bhat P. N, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Br, dt T. J, Bregeon J, Brez A, Briggs M. S, Brigida M, Bruel P, Buehler R, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cavazzuti E, Cecchi C, Celik O, Charles E, Chekhtman A, Chen A. W, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Connaughton V, Conrad J, Costamante L, Dermer C. D, de Angelis A, de Palma F, Digel S. W, Dingus B. L, do Couto e, Silva E, Drell P. S, Dubois R, Favuzzi C, Fegan S. J, Finke J, Fortin P, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Gilmore R. C, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Granot J, Greiner J, Grenier I. A, Grove J. E, Guiriec S, Gustafsson M, Hadasch D, Hayashida M, Hays E, Horan D, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kocevski D, Kuss M, Lande J, Latronico L, Lee S-H, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Mazziotta N, McConville W, McEnery J. E, McGlynn S, Mehault J, Meszaros P, Michelson P. F, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Primack J. R, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reyes L. C, Ripken J, Ritz S, Romani R. W, Roth M, Sadrozinski H. F. -W, Sanchez D, Sander A, Scargle J. D, Schalk T. L, Sgro C, Shaw M. S, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Stecker F. W, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vilchez N, Vitale V, von Kienlin A, Waite A. P, Wang P, Wilson-Hodge C, Winer B. L, Wood K. S, Yamazaki R, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 723 ( 2 ) 1082 - 1096 2010年11月 [査読有り]

DOI

Scopus

139

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE OBSERVATION OF A GAMMA-RAY SOURCE AT THE POSITION OF ETA CARINAE

Abdo A. A, Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bonamente E, Borgland A. W, Bouvier A, Br, dt T. J, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Burnett T. H, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cecchi C, Celik Oe, Chaty S, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Conrad J, Dermer C. D, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Favuzzi C, Fegan S. J, Ferrara E. C, Frailis M, Fukazawa Y, Fusco P, Gargano F, Gehrels N, Germani S, Giglietto N, Giordano F, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hill A. B, Horan D, Hughes R. E, Itoh R, Jackson M. S, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Livingstone M, Garde M. Llena, Longo F, Loparco F, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Rodriguez A. Y, Romani R. W, Roth M, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wallace E, Wang P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 723 ( 1 ) 649 - 657 2010年11月 [査読有り]

DOI

Scopus

76

被引用数

(Scopus)
FERMI-LAT STUDY OF GAMMA-RAY EMISSION IN THE DIRECTION OF SUPERNOVA REMNANT W49B

Abdo A. A, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Dermer C. D, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Dumora D, Favuzzi C, Funk S, Fusco P, Gargano F, Gehrels N, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grondin M-H, Grove J. E, Guillemot L, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hayashida M, Hays E, Horan D, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Katsuta J, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S-H, Lemoine-Goumard M, Longo F, Loparco F, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ripken J, Roth M, Sadrozinski H. FW, Sander A, Parkinson P, M. Saz, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spinelli P, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 722 ( 2 ) 1303 - 1311 2010年10月 [査読有り]

DOI

Scopus

100

被引用数

(Scopus)
GAMMA-RAY LIGHT CURVES AND VARIABILITY OF BRIGHT FERMI-DETECTED BLAZARS

Abdo A. A, Ackermann M, Ajello M, Antolini E, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Conrad J, Costamante L, Cutini S, Dermer C. D, de Angelis A, de Palma F, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M.-H, Grove J. E, Guiriec S, Hadasch D, Hayashida M, Hays E, Healey S. E, Horan D, Hughes R. E, Itoh R, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Knoedlseder J, Kuss M, Lande J, Larsson S, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Massaro E, Mazziotta M. N, McEnery J. E, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Mueller M, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Ritz S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F.-W, Sander A, Scargle J. D, Sgro C, Shaw M. S, Smith P. D, Spandre G, Spinelli P, Starck J.-L, Strickman M. S, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wallace E, Wang P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 722 ( 1 ) 520 - 542 2010年10月 [査読有り]

DOI

Scopus

319

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE AND MULTI-WAVELENGTH OBSERVATIONS OF THE FLARING ACTIVITY OF PKS 1510-089 BETWEEN 2008 SEPTEMBER AND 2009 JUNE

Abdo A. A, Ackermann M, Agudo I, Ajello M, Allafort A, Aller H. D, Aller M. F, Antolini E, Arkharov A. A, Axelsson M, Bach U, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berdyugin A, Berenji B, Blandford R. D, Blinov D. A, Bloom E. D, Boettcher M, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Buemi C. S, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carosati D, Carrigan S, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Chekhtman A, Chen W. P, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Corbel S, Costamante L, Dermer C. D, de Angelis A, de Palma F, Donato D, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Forne E, Fortin P, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grove J. E, Guiriec S, Gurwell M. A, Gusbar C, Gomez J. L, Hadasch D, Hagen-Thorn V. A, Hayashida M, Hays E, Horan D, Hughes R. E, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kimeridze G, Knoedlseder J, Konstantinova T. S, Kopatskaya E. N, Koptelova E, Kovalev Y. Y, Kurtanidze O. M, Kuss M, Lahteenmaki A, Lande J, Larionov V. M, Larionova E. G, Larionova L. V, Larsson S, Latronico L, Lee S. -H, Leto P, Lister M. L, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Massaro E, Mazziotta M. N, McConville W, McEnery J. E, McHardy I. M, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morozova D. A, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Nikolashvili M. G, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pasanen M, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Pushkarev A. B, Raino S, Raiteri C. M, Rando R, Razzano M, Reimer A, Reimer O, Reinthal R, Ripken J, Ritz S, Roca-Sogorb M, Rodriguez A. Y, Roth M, Roustazadeh P, Ryde F, Sadrozinski H. F. -W, Sander A, Scargle J. D, Sgro C, Sigua L. A, Smith P. D, Sokolovsky K, Spandre G, Spinelli P, Starck J. -L, Strickman M. S, Suson D. J, Takahashi H, Takahashi T, Takalo L. O, Tanaka T, Taylor B, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Tornikoski M, Torres D. F, Tosti G, Tramacere A, Trigilio C, Troitsky I. S, Umana G, Usher T. L, Vandenbroucke J, Vasileiou V, Vilchez N, Villata M, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 721 ( 2 ) 1425 - 1447 2010年10月 [査読有り]

DOI

Scopus

103

被引用数

(Scopus)
FERMI GAMMA-RAY SPACE TELESCOPE OBSERVATIONS OF GAMMA-RAY OUTBURSTS FROM 3C 454.3 IN 2009 DECEMBER AND 2010 APRIL

Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bonamente E, Borgland A. W, Bregeon J, Brigida M, Bruel P, Buehler R, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Corbel S, Cutini S, D'Ammando F, Dermer C. D, de Angelis A, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Escande L, Favuzzi C, Fegan S. J, Ferrara E. C, Fuhrmann L, Fukazawa Y, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grove J. E, Guiriec S, Hadasch D, Hayashida M, Hays E, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Larsson S, Latronico L, Lee S. -H, Garde M. Llena, Longo F, Loparco F, Lott B, Lubrano P, Madejski G. M, Makeev A, Marchili N, Mazziotta M. N, McEnery J. E, Mehault J, Michelson P. F, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nalewajko K, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reyes L. C, Ripken J, Ritz S, Roth M, Sadrozinski H. F. -W, Sanchez D, Sander A, Scargle J. D, Sgro C, Sikora M, Siskind E. J, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Tanaka Y, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Usher T. L, Vandenbroucke J, Vilchez N, Vitale V, Waite A. P, Wang P, Wehrle A. E, Winer B. L, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 721 ( 2 ) 1383 - 1396 2010年10月 [査読有り]

DOI

Scopus

137

被引用数

(Scopus)
Development of X-ray/Gamma-ray Imaging Spectrometer with Reach-through APD arrays

Nakamori, T, Enomoto, T, Toizumi, T, Yatsu, Y, Kawai, N, Kataoka, J, Ishikawa, Y, Kawai, T, Kawabata, N, Matsunaga, Y

AIP Conference Proceedings 1279 400 - 402 2010年10月

DOI

Scopus

2

被引用数

(Scopus)
Development of an APD-Based PET Module and Preliminary Resolution Performance of an Experimental Prototype Gantry

Jun Kataoka, Hidenori Matsuda, Fumihiko Nishikido, Makoto Koizumi, Hirokazu Ikeda, Masao Yoshino, Takamasa Miura, Satoshi Tanaka, Yoshitaka Ishikawa, Nobuyuki Kawabata, Keiji Shimizu, Yusuke Matsunaga, Shunji Kishimoto, Hidetoshi Kubo, Yoshio Yanagida, Takeshi Nakamori

IEEE TRANSACTIONS ON NUCLEAR SCIENCE 57 ( 5 ) 2448 - 2454 2010年10月

　概要を見る

The development of a high-resolution Positron Emission Tomography (PET) technique with sub-millimeter spatial resolution, which utilizes newly designed reverse-type APD-arrays, is uderway. All the detector blocks are modularized with the overall dimension of each module, including the APD array, LYSO scintillator matrix and Front-End Circuits (FECs), which are only 30 x 30 x 80 mm(3). Each APD device also has a monolithic 16 x 16 pixel structure with an active area of 1.0 mm(2) per pixel. The FEC includes two identical analog ASICs specifically designed for APDs with a noise characteristic of 560 + 30 e(-)/pF and a timing resolution of 460 ps (rms), respectively. An energy resolution of 13.7 +/- 1.1% (FWHM) with 662 keV gamma-rays was measured using the 16 x 16 arrays. At this stage a pair of module and coincidence circuits has been assembled into an experimental prototype gantry. Spatial resolutions of 0.9, 1.4, and 1.3 mm (FWHM) were obtained from FBP reconstructed images in preliminary experiments with a point source positioned centrally, and 1 and 5 mm off-center, respectively. Comparison with a Monte-Carlo simulation of a fully-designed gantry over a wider range of field-of-view showed good correlation with the experimental data. A simple but conceptual design of a DOI configuration is also proposed as a test example of a future APD-PET scanner.

DOI

Scopus

19

被引用数

(Scopus)
APD-PETモジュールの開発と解像度の実験的検証

J.Kataoka

IEEE Transactions on Nuclear Science 57 ( 5 ) 2448 - 2454 2010年10月 [査読有り]

DOI

Scopus

19

被引用数

(Scopus)
FERMI-LAT OBSERVATIONS OF THE GEMINGA PULSAR

Abdo A. A, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastier D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Bignami G. F, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Brueli P, Burnett T. H, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Dermer C. D, de Palma F, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Edmonds Y, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Furazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hadasch D, Hardino A. K, Hays E, Hughes R. E, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Marelli M, Mazziotta M. N, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenk I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Rayi P. S, Razzano M, Reimer A, Reimer O, Reposeur T, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Usher T. L, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wang P, Watters K, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 720 ( 1 ) 272 - 283 2010年09月 [査読有り]

DOI

Scopus

73

被引用数

(Scopus)
THE FERMI-LAT HIGH-LATITUDE SURVEY: SOURCE COUNT DISTRIBUTIONS AND THE ORIGIN OF THE EXTRAGALACTIC DIFFUSE BACKGROUND

Abdo A. A, Ackermann M, Ajello M, Antolini E, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Costamante L, Cutini S, Dermer C. D, de Angelis A, de Palma F, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grove J. E, Guiriec S, Hadasch D, Hayashida M, Hays E, Healey S. E, Horan D, Hughes R. E, Itoh R, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lurrano P, Madejski G. M, Makeev A, Mazziotta M. N, McConville W, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzan M, Reimer A, Reimer O, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Shaw M. S, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Strickman M. S, Strong A. W, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 720 ( 1 ) 435 - 453 2010年09月 [査読有り]

DOI

Scopus

184

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF GAMMA-RAY PULSARS PSR J1057-5226, J1709-4429, AND J1952+3252

Ardo A. A, Ajello M, Antolini E, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Burnett T. H, Buson S, Caliandro G. A, Camilo F, Caraveo P. A, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Dermer C. D, De Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Favuzzi C, Ferrara E. C, Fortin P, Frailis M, Freire P. C. C, Fukazawa Y, Funk S, Fusco P, Gargano F, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hays E, Johannesson G, Johnson R. P, Johnson T. J, Johnson W. N, Johnston S, Kamae T, Katagiri H, Kataoka J, Keith M, Kerr M, Knoedlseder J, Kramer M, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lubrano P, Makeev A, Manchester R. N, Marelli M, Mazziotta M. N, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Mnzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Noutos A, Nuss E, Ohsugi T, Okumura A, Orlando E, Ormes J. F, Ozaki M, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Raino S, Razzano M, Reimer A, Reimer O, Reposeur T, Rirken J, Romani R. W, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Theureau G, Thompson D. J, Thorsett S. E, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Usher T. L, Vandenbroucke J, Vasileiou V, Vitale V, Waite A. P, Wang P, Weltevrede P, Winer B. L, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 720 ( 1 ) 26 - 40 2010年09月 [査読有り]

DOI

Scopus

28

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF MISALIGNED ACTIVE GALACTIC NUCLEI

Abdo A. A, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Br, dt T. J, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Cannon A, Caraveo P. A, Carrigan S, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Celotti A, Charles E, Chekhtman A, Chen A. W, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Colafrancesco S, Conrad J, Davis D. S, Dermer C. D, de Angelis A, de Palma F, do Couto e, Silva E, Drell P. S, Dubois R, Favuzzi C, Fegan S. J, Ferrara E. C, Fortin P, Frailis M, Fukazawa Y, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grandi P, Grenier I. A, Grove J. E, Guillemot L, Guiriec S, Hadasch D, Hayashida M, Hays E, Horan D, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S-H, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Malaguti G, Mazziotta M. N, McConville W, McEnery J. E, Michelson P. F, Migliori G, Mitthumsiri W, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Naumann-Godo M, Nestoras I, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Persic M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reyes L. C, Roth M, Sadrozinski H. F-W, Sanchez D, Sander A, Scargle J. D, Sgro C, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Stawarz L, Stecker F. W, Strickman M. S, Suson D. J, Takahashi H, Tanaka T, Thayer J. B, Thaver J. G, Thompson D. J, Tibaldo L, Torres D. F, Torresi E, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vilchez N, Villata M, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 720 ( 1 ) 912 - 922 2010年09月 [査読有り]

DOI

Scopus

164

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE VIEW OF THE CORE OF THE RADIO GALAXY CENTAURUS A

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Br, dt T. J, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Cannon A, Caraveo P. A, Carrigan S, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Colafrancesco S, Cominsky L. R, Conrad J, Costamante L, Davis D. S, Dermer C. D, de Angelis A, de Palma F, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Falcone A, Farnier C, Favuzzi C, Fegan S. J, Finke J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Georganopoulos M, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grandi P, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hadasch D, Harding A. K, Hase Hayo, Hayashida M, Hays E, Horan D, Hughes R. E, Itoh R, Jackson M. S, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Kadler M, Kamae T, Katagiri H, Kataoka J, Kawai N, Kishishita T, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, McConville W, McEnery J. E, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Mueller C, Nakamori T, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Ojha R, Okumura A, Omodei N, Orlando E, Ormes J. F, Ozaki M, Pagani C, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Plotz C, Porter T. A, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reposeur T, Ripken J, Ritz S, Rodriguez A. Y, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Scargle J. D, Sgro C, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Stawarz L, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vandenbroucke J, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 719 ( 2 ) 1433 - 1444 2010年08月 [査読有り]

DOI

Scopus

154

被引用数

(Scopus)
Gamma-Ray Emission Concurrent with the Nova in the Symbiotic Binary V407 Cygni

Abdo, A. A, Ackermann, M, Ajello, M, Atwood, W. B, Baldini, L, Ballet, J, Barbiellini, G, Bastieri, D, Bechtol, K, Bellazzini, R, Berenji, B, Blandford, R. D, Bloom, E. D, Bonamente, E, Borgland, A. W, Bouvier, A, Brandt, T. J, Bregeon, J, Brez, A, Brigida, M, Bruel, P, Buehler, R, Burnett, T. H, Buson, S, Caliandro, G. A, Cameron, R. A, Caraveo, P. A, Carrigan, S, Casandjian, J. M, Cecchi, C, Celik, O, Charles, E, Chaty, S, Chekhtman, A, Cheung, C. C, Chiang, J, Ciprini, S, Claus, R, Cohen-Tanugi, J, Conrad, J, Corbel, S, Corbet, R, DeCesar, M. E, den Hartog, P. R, Dermer, C. D, de Palma, F, Digel, S. W, Donato, D, do Couto e, Silva, E, Drell, P. S, Dubois, R, Dubus, G, Dumora, D, Favuzzi, C, Fegan, S. J, Ferrara, E. C, Fortin, P, Frailis, M, Fuhrmann, L, Fukazawa, Y, Funk, S, Fusco, P, Gargano, F, Gasparrini, D, Gehrels, N, Germani, S, Giglietto, N, Giordano, F, Giroletti, M, Glanzman, T, Godfrey, G, Grenier, I. A, Grondin, M. -H, Grove, J. E, Guiriec, S, Hadasch, D, Harding, A. K, Hayashida, M, Hays, E, Healey, S. E, Hill, A. B, Horan, D, Hughes, R. E, Itoh, R, Jean, P, Johannesson, G, Johnson, A. S, Johnson, R. P, Johnson, T. J, Johnson, W. N, Kamae, T, Katagiri, H, Kataoka, J, Kerr, M, Knodlseder, J, Koerding, E, Kuss, M, Lande, J, Lande, J, Lee, S. -H, Lemoine-Goumard, M, Llena Garde, M, Longo, F, Loparco, F, Lott, B, Lovellette, M. N, Lubrano, P, Makeev, A, Mazziotta, M. N, McConville, W, McEnery, J. E, Mehault, J, Michelson, P. F, Mizuno, T, Moiseev, A. A, Monte, C, Monzani, M. E, Morselli, A, Moskalenko, I. V, Murgia, S, Nakamori, T, Naumann-Godo, M, Nestoras, I, Nolan, P. L, Norris, J. P, Nuss, E, Ohno, M, Ohsugi, T, Okumura, A, Omodei, N, Orlando, E, Ormes, J. F, Ozaki, M, Paneque, D, Panetta, J. H, Parent, D, Pelassa, V, Pepe, M, Pesce-Rollins, M, Piron, F, Porter, T. A, Raino, S, Rando, R, Ray, P. S, Razzano, M, Razzaque, S, Rea, N, Reimer, A, Reimer, O, Reposeur, T, Ripken, J, Ritz, S, Romani, R. W, Roth, M, Sadrozinski, H. F. W, Sander, A, Parkinson, P. M. Saz, Scargle, J. D, Schinzel, F. K, Sgro, C, Shaw, M. S, Siskind, E. J, Smith, D. A, Smith, P. D, Sokolovsky, K. V, Spandre, G, Spinelli, P, Stawarz, L, Strickman, M. S, Suson, D. J, Takahashi, H, Takahashi, T, Tanaka, T, Tanaka, Y, Thayer, J. B, Thayer, J. G, Thompson, D. J, Tibaldo, L, Torres, D. F, Tosti, G, Tramacere, A, Uchiyama, Y, Usher, T. L, Vandenbroucke, J, Vasileiou, V, Vilchez, N, Vitale, V, Waite, A. P, Wallace, E, Wang, P, Winer, B. L, Wolff, M. T, Wood, K. S, Yang, Z, Ylinen, T, Ziegler, M, Maehara, H, Nishiyama, K, Kabashima, F, Bach, U, Bower, G. C, Falcone, A, Forster, J. R, Henden, A, Kawabata, K. S, Koubsky, P, Mukai, K, Nelson, T, Oates, S. R, Sakimoto, K, Sasada, M, Shenavrin, V. I, Shore, S. N, Skinner, G. K, Sokoloski, J, Stroh, M, Tatarnikov, A

SCIENCE 329 ( 5993 ) 817 - 821 2010年08月 [査読有り]

　概要を見る

Novae are thermonuclear explosions on a white dwarf surface fueled by mass accreted from a companion star. Current physical models posit that shocked expanding gas from the nova shell can produce x-ray emission, but emission at higher energies has not been widely expected. Here, we report the Fermi Large Area Telescope detection of variable gamma-ray emission (0.1 to 10 billion electron volts) from the recently detected optical nova of the symbiotic star V407 Cygni. We propose that the material of the nova shell interacts with the dense ambient medium of the red giant primary and that particles can be accelerated effectively to produce pi(0) decay gamma-rays from proton-proton interactions. Emission involving inverse Compton scattering of the red giant radiation is also considered and is not ruled out.

DOI

Scopus

214

被引用数

(Scopus)
フェルミ衛星による活動銀河ジェット観測の新展開

片岡淳ほか

日本天文学会誌 103 486 2010年08月
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE SUPERNOVA REMNANT W28 (G6.4-0.1)

Abdo A. A, Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Br, dt T. J, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Dermer C. D, de Palma F, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Fukazawa Y, Fukui Y, Funk S, Fusco P, Gargano F, Gehrels N, Germani S, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grove J. E, Guiriec S, Hadasch D, Hanabata Y, Harding A. K, Hays E, Horan D, Hughes R. E, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Rodriguez Y, Roth M, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Uchiyama Y, Uehara T, Usher T. L, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yamamoto H, Yamazaki R, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 718 ( 1 ) 348 - 356 2010年07月 [査読有り]

DOI

Scopus

205

被引用数

(Scopus)
GeV gamma-ray flux upper limits from clusters of galaxies

M. Ackermann, M. Ajello, A. Allafort, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, R. D. Blandford, P. Blasi, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, T. J. Brandt, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, S. Carrigan, J. M. Casandjian, E. Cavazzuti, C. Cecchi, Çelik, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, L. R. Cominsky, J. Conrad, C. D. Dermer, F. De Palma, E. Do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, C. Farnier, C. Favuzzi, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, S. Guiriec, D. Hadasch, A. K. Harding, M. Hayashida, E. Hays, D. Horan, R. E. Hughes, T. E. Jeltema, G. Jóhannesson, A. S. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, S. H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. N. Mazziotta, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli

Astrophysical Journal Letters 717 ( 1 ) L71 - L78 2010年07月

　概要を見る

The detection of diffuse radio emission associated with clusters of galaxies indicates populations of relativistic leptons infusing the intraclustermedium (ICM). Those electrons and positrons are either injected into and accelerated directly in the ICM, or produced as secondary pairs by cosmic-ray ions scattering on ambient protons. Radiation mechanisms involving the energetic leptons together with the decay of neutral pions produced by hadronic interactions have the potential to produce abundant GeV photons. Here, we report on the search for GeV emission from clusters of galaxies using data collected by the Large Area Telescope on the FermiGamma-ray Space Telescope from 2008 August to 2010 February. Thirty-three galaxy clusters have been selected according to their proximity and high mass, X-ray flux and temperature, and indications of non-thermal activity for this study. We report upper limits on the photon flux in the range 0.2-100GeVtoward a sample of observed clusters (typical values (1-5)×10-9 photon cm-2 s-1) considering both point-like and spatially resolved models for the high-energy emission and discuss how these results constrain the characteristics of energetic leptons and hadrons, and magnetic fields in the ICM. The volume-averaged relativistic-hadron-to-thermal energy density ratio is found to be <5%-10% in several clusters.

DOI

Scopus

153

被引用数

(Scopus)
フェルミガンマ線宇宙望遠鏡で探る微弱ガンマ線天体

深沢泰司, 片岡淳, 高橋忠幸, Behalf of the, Fermi LAT Collaboration

天文月報 103 ( 8 ) 494 - 500 2010年07月

CiNii
フェルミ衛星による活動銀河ジェット観測の新展開

片岡淳, 深沢泰司, Stawarz Lukasz, 佐藤理江, 林田将明, Behalf of the, Fermi LAT Collaboration

天文月報 103 ( 8 ) 486 - 493 2010年07月

CiNii
FERMI OBSERVATIONS OF GRB 090510: A SHORT-HARD GAMMA-RAY BURST WITH AN ADDITIONAL, HARD POWER-LAW COMPONENT FROM 10 keV TO GeV ENERGIES

Ackermann M, Asano K, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bhat P. N, Bissaldi E, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Briggs M. S, Brigida M, Bruel P, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cecchi C, Celik Oe, Charles E, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Connaughton V, Conrad J, Dermer C. D, de Palma F, Dingus B. L, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Finke J, Focke W. B, Frailis M, Fukazawa Y, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Glanzman T, Godfrey G, Granot J, Grenier I. A, Grondin M. -H, Grove J. E, Guiriec S, Hadasch D, Harding A. K, Hays E, Horan D, Hughes R. E, Johannesson G, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kippen R. M, Knoedlseder J, Kocevski D, Kouveliotou C, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, McEnery J. E, McGlynn S, Meegan C, Meszaros P, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakajima H, Nakamori T, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paciesas W. S, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Preece R, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Ritz S, Rodriguez A. Y, Roth M, Ryde F, Sadrozinski H. F. -W, Sander A, Scargle J. D, Schalk T. L, Sgro C, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Stamatikos M, Stecker F. W, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Toma K, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Uehara T, Usher T. L, van der Horst A. J, Vasileiou V, Vilchez N, Vitale V, von Kienlin A, Waite A. P, Wang P, Wilson-Hodge C, Winer B. L, Wu X. F, Yamazaki R, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 716 ( 2 ) 1178 - 1190 2010年06月 [査読有り]

DOI

Scopus

356

被引用数

(Scopus)
SUZAKU OBSERVATIONS OF LUMINOUS QUASARS: REVEALING THE NATURE OF HIGH-ENERGY BLAZAR EMISSION IN LOW-LEVEL ACTIVITY STATES

Abdo A. A, Ackermann M, Ajello M, Antolini E, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Buson S, Caliandro G. A, Cameron R. A, Carrigan S, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Chekhtman A, Chen A. W, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Colafrancesco S, Conrad J, Cutini S, Dermer C. D, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Frailis M, Fukazawa Y, Fusco P, Gargano F, Gasparrini D, Gehrels N, Giebels B, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grandi P, Grenier I. A, Guillemot L, Guiriec S, Hadasch D, Harding A. K, Hayashida M, Horan D, Hughes R. E, Itoh R, Jackson M. S, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Knoedlseder J, Kuss M, Lande J, Latronico L, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, McEnery J. E, McGlynn S, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nestoras I, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reyes L. C, Rodriguez A. Y, Roth M, Ryde F, Sadrozinski H. F. -W, Sambruna R, Sander A, Sato R, Sgro C, Shaw M. S, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Stawarz L, Stecker F. W, Strickman M. S, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibolla O, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Villata M, Vitale V, von Kienlin A, Waite A. P, Wang P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M, Tavecchio F, Sikora M, Schady P, Roming P, Chester M. M, Maraschi L

ASTROPHYSICAL JOURNAL 716 ( 1 ) 835 - 849 2010年06月 [査読有り]

DOI

Scopus

25

被引用数

(Scopus)
THE SPECTRAL ENERGY DISTRIBUTION OF FERMI BRIGHT BLAZARS

Abdo A. A, Ackermann M, Agudo I, Ajello M, Aller H. D, Aller M. F, Angelakis E, Arkharov A. A, Axelsson M, Bach U, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Benitez E, Berdyugin A, Berenji B, Blandford R. D, Bloom E. D, Boettcher M, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Burrows D, Buson S, Caliandro G. A, Calzoletti L, Cameron R. A, Capalbi M, Caraveo P. A, Carosati D, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Charles E, Chaty S, Chekhtman A, Chen W. P, Chiang J, Chincarini G, Ciprini S, Claus R, Cohen-Tanugi J, Colafrancesco S, Cominsky L. R, Conrad J, Costamante L, Cutini S, D'ammando F, Deitrick R, D'Elia V, Dermer C. D, de Angelis A, de Palma F, Digel S. W, Donnarumma I, do Couto e, Silva E, Drell P. S, Dubois R, Dultzin D, Dumora D, Falcone A, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Forne E, Fortin P, Frailis M, Fuhrmann L, Fukazawa Y, Funk S, Fusco P, Gomez J. L, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Giuliani A, Glanzman T, Godfrey G, Grenier I. A, Gronwall C, Grove J. E, Guillemot L, Guiriec S, Gurwell M. A, Hadasch D, Hanabata Y, Harding A. K, Hayashida M, Hays E, Healey S. E, Heidt J, Hiriart D, Horan D, Hoversten E. A, Hughes R. E, Itoh R, Jackson M. S, Johannesson G, Johnson A. S, Johnson W. N, Jorstad S. G, Kadler M, Kamae T, Katagiri H, Kataoka J, Kawai N, Kennea J, Kerr M, Kimeridze G, Knoedlseder J, Kocian M. L, Kopatskaya E. N, Koptelova E, Konstantinova T. S, Kovalev Y. Y, Kovalev Yu. A, Kurtanidze O. M, Kuss M, Lande J, Larionov V. M, Latronico L, Leto P, Lindfors E, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Marchegiani P, Marscher A. P, Marshall F, Max-Moerbeck W, Mazziotta M. N, McConville W, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nestoras I, Nilsson K, Nizhelsky N. A, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Ojha R, Omodei N, Orlando E, Ormes J. F, Osborne J, Ozaki M, Pacciani L, Padovani P, Pagani C, Page K, Paneque D, Panetta J. H, Parent D, Pasanen M, Pavlidou V, Pelassa V, Pepe M, Perri M, Pesce-Rollins M, Piranomonte S, Piron F, Pittori C, Porter T. A, Puccetti S, Rahoui F, Raino S, Raiteri C, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Richards J. L, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Ros J. A, Roth M, Roustazadeh P, Ryde F, Sadrozinski H. F. -W, Sadun A, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sellerholm A, Sgro C, Shaw M. S, Sigua L. A, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Stevenson M, Stratta G, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Takalo L. O, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Verrecchia F, Vilchez N, Villata M, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Ylinen T, Zensus J. A, Zhekanis G. V, Ziegler M

ASTROPHYSICAL JOURNAL 716 ( 1 ) 30 - 70 2010年06月 [査読有り]

DOI

Scopus

820

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE FIRST SOURCE CATALOG

Abdo A. A, Ackermann M, Ajello M, Allafort A, Antolini E, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Belli F, Berenji B, Bisello D, Blandford R. D, Bloom E. D, Bonamente E, Bonnell J, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Busetto G, Buson S, Caliandro G. A, Cameron R. A, Campana R, Canadas B, Caraveo P. A, Carrigan S, Casandjian J. M, Cavazzuti E, Ceccanti M, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Cillis A. N, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Corbet R, Davis D. S, DeKlotz M, den Hartog P. R, Dermer C. D, de Angelis A, de Luca A, de Palma F, Digel S. W, Dormody M, do Couto E, Silva E, Drell P. S, Dubois R, Dumora D, Fabiani D, Farnier C, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giebels B, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Gustafsson M, Hadasch D, Hanabata Y, Harding A. K, Hayashida M, Hays E, Healey S. E, Hill A. B, Horan D, Hughes R. E, Iafrate G, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocevski D, Kuss M, Lande J, Landriu D, Latronico L, Lee S. -H, Lemoine-Goumard M, Lionetto A. M, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Marangelli B, Marelli M, Massaro E, Mazziotta M. N, McConville W, McEnery J. E, Michelson P. F, Minuti M, Mitthumsiri W, Mizuno T, Moiseev A. A, Mongelli M, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakajima H, Nakamori T, Naumann-Godo M, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paccagnella A, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Pinchera M, Piron F, Porter T. A, Poupard L, Raino S, Rando R, Ray P. S, Razzano M, Razzaque S, Rea N, Reimer A, Reimer O, Reposeur T, Ripken J, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Sadrozinski H. F. -W, Salvetti D, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Schalk T. L, Scolieri G, Sgro C, Shaw M. S, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Stephens T. E, Striani E, Strickman M. S, Strong A. W, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Tibolla O, Tinebra F, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Van Etten A, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wallace E, Wang P, Watters K, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES 188 ( 2 ) 405 - 436 2010年06月 [査読有り]

DOI

Scopus

980

被引用数

(Scopus)
大面積APDアレーの開発と次世代PET技術への展望

片岡淳

放射線 35 ( 4 ) 277 - 287 2010年06月

CiNii
大面積APDアレーの開発と次世代PET技術への展望

片岡淳

放射線（応用物理学会・放射線分科会） 35 ( 4 ) 277 - 287 2010年06月

CiNii
THE FIRST CATALOG OF ACTIVE GALACTIC NUCLEI DETECTED BY THE FERMI LARGE AREA TELESCOPE

Abdo A. A, Ackermann M, Ajello M, Allafort A, Antolini E, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bogart J. R, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Cannon A, Caraveo P. A, Carrigan S, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Celotti A, Charles E, Chekhtman A, Chen A. W, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Costamante L, Cotter G, Cutini S, D'Elia V, Dermer C. D, de Angelis A, de Palma F, De Rosa A, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Escande L, Farnier C, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grandi P, Grenier I. A, Grondin M. -H, Grove J. E, Guiriec S, Hadasch D, Harding A. K, Hayashida M, Hays E, Healey S. E, Hill A. B, Horan D, Hughes R. E, Iafrate G, Itoh R, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lavalley C, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Malaguti G, Massaro E, Mazziotta M. N, McConville W, McEnery J. E, McGlynn S, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piranomonte S, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ripken J, Ritz S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Shaw M. S, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Stawarz L, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Taylor G. B, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Ubertini P, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Villata M, Vitale V, Waite A. P, Wallace E, Wang P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 715 ( 1 ) 429 - 457 2010年05月 [査読有り]

DOI

Scopus

470

被引用数

(Scopus)
In-orbit performance of avalanche photodiode as radiation detector on board the picosatellite Cute-1.7+APD II

Kataoka, J, Toizumi, T, Nakamroi, T, Yatsu, Y, Tsubuku, Y, Kuramoto, Y, Enomoto, T, Usui, R, Kawai, N, Ashida, H, Omagari, K, Fujihashi, K, Inagawa, S, Miura, Y, Konda, Y, Miyashita, N, Matsunaga, S, Ishikawa, Y, Matsunaga, Y, Kawabata, N

Journal of Geophysical Research 115 ( 5 ) A05204 - (9pp) 2010年05月 [査読有り]

DOI

Scopus

41

被引用数

(Scopus)
Fermi Gamma-Ray Imaging of a Radio Galaxy

SCIENCE 328 ( 5979 ) 725 - 729 2010年05月 [査読有り]

DOI

Scopus

217

被引用数

(Scopus)
Design of Tokyo Tech nano-satellite Cute-1.7+APD II and its operation

Hiroki Ashida, Kota Fujihashi, Shinichi Inagawa, Yoshiyuki Miura, Kuniyuki Omagari, Naoki Miyashita, Saburo Matunaga, Takahiro Toizumi, Jun Kataoka, Nobuyuki Kawai

Acta Astronautica 66 ( 9-10 ) 1412 - 1424 2010年05月

　概要を見る

Cute-1.7+APD II is the 3rd satellite developed by the Laboratory for Space Systems at the Tokyo Institute of Technology. Cute-1.7+APD II is the current successor to Cute-1.7+APD. This new satellite is based on its predecessor but has some modifications to increase its reliability and robustness against radiation effects, electrical power shortage and so on. The satellite was launched by an ISRO PSLV-C9 rocket on April 28, 2008 and has operated for more than 9 months. Throughout its operation, many missions such as attitude determination and control experiments, scientific observations, photographing and communication experiments have been conducted. In this paper an overview of the Cute-1.7 series and configurations, modifications and operation results of Cute-1.7+APD II are introduced. © 2009 Elsevier Ltd. All rights reserved.

DOI

Scopus

41

被引用数

(Scopus)
DETECTION OF THE ENERGETIC PULSAR PSR B1509-58 AND ITS PULSAR WIND NEBULA IN MSH 15-52 USING THE FERMI-LARGE AREA TELESCOPE

Abdo A. A, Ackermann M, Ajello M, Allafort A, Asano K, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Buson S, Caliandro G. A, Cameron R. A, Camilo F, Caraveo P. A, Carrigan S, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, den Hartog P. R, Dermer C. D, de Luca A, de Palma F, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gehrels N, Germani S, Giglietto N, Giordano F, Glanzman T, Godfrey G, Gotthelf E. V, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hays E, Hobbs G, Horan D, Hughes R. E, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Johnston S, Kamae T, Kanai Y, Kanbach G, Katagiri H, Kataoka J, Kawai N, Keith M, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Manchester R. N, Marelli M, Mazziotta M. N, McEnery J. E, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Rea N, Reimer A, Reimer O, Reposeur T, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Strickman M. S, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Thorsett S. E, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wang P, Weltevrede P, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 714 ( 1 ) 927 - 936 2010年05月 [査読有り]

DOI

Scopus

80

被引用数

(Scopus)
FERMI-LARGE AREA TELESCOPE OBSERVATIONS OF THE EXCEPTIONAL GAMMA-RAY OUTBURSTS OF 3C 273 IN 2009 SEPTEMBER

Abdo A. A, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Cannon A, Caraveo P. A, Carrigan S, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Costamante L, Dermer C. D, de Angelis A, de Palma F, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Guiriec S, Hayashida M, Hays E, Hill A. B, Horan D, Hughes R. E, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Knoedlseder J, Kuss M, Lande J, Larsson S, Latronico L, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mansutti O, Massaro E, Mazziotta M. N, McConville W, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Ritz S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sander A, Scargle J. D, Schalk T. L, Sgro C, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Wehrle A. E, Winer B. L, Wood K. S, Yang Z, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL LETTERS 714 ( 1 ) L73 - L78 2010年05月 [査読有り]

DOI

Scopus

47

被引用数

(Scopus)
フェルミ衛星による電波銀河 NGC127のガンマ線スペクトル変動の観測

J.Kataoka

The Astrophysical Journal 715 ( 1 ) 554 - 560 2010年05月 [査読有り]

DOI

Scopus

54

被引用数

(Scopus)
THE VELA PULSAR: RESULTS FROM THE FIRST YEAR OF FERMI LAT OBSERVATIONS

Abdo A. A, Ackermann M, Ajello M, Allafort A, Atwood W. B, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Blandford D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Dermer C. D, de Luca A, de Palma F, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hadasch D, Harding A. K, Hays E, Hobbs G, Horan D, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Manchester R. N, Marelli M, Mazziotta M. N, McConville W, McEnery J. E, McGlynn S, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Noutsos A, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Pierbattista M, Piron F, Porter T. A, Raino S, Rando R, Ray P. S, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Strickman M. S, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Usher T. L, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wang P, Watters K, Weltevrede P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 713 ( 1 ) 154 - 165 2010年04月 [査読有り]

DOI

Scopus

114

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE VELA-X PULSAR WIND NEBULA

Abdo A. A, Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Chung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, de Angelis A, de Palma F, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gehrels N, Germani S, Giavitto G, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Harding A. K, Hayashida M, Hays E, Horan D, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Johnston S, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Marelli M, Mazziotta M. N, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Noutsos A, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Pierbattista M, Piron F, Porter T. A, Raino S, Rando R, Ray P. S, Rea N, Reimer A, Reimer O, Reposeur T, Ritz S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wang P, Weltevrede P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 713 ( 1 ) 146 - 153 2010年04月 [査読有り]

DOI

Scopus

67

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF PSR J1836+5925

Abdo A. A, Ackermann M, Ajello M, Atwood B, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Belfiore A, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Camilo F, Caraveo P. A, Carrigan S, Casandjian J. M, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, de Angelis A, de Luca A, de Palma F, Digel S. W, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Edmonds Y, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Gwon C, Hadasch D, Harding A. K, Hays E, Horan D, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Kamae T, Kanai Y, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Marelli M, Mazziotta M. N, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Pierbattista M, Piron F, Porter T. A, Raino S, Rando R, Ransom S. M, Ray P. S, Razzano M, Rea N, Reimer A, Reimer O, Reposeur T, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Thorsett S. E, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Usher T. L, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wang P, Watters K, Winer B. L, Wolff M. T, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 712 ( 2 ) 1209 - 1218 2010年04月 [査読有り]

DOI

Scopus

35

被引用数

(Scopus)
THE FIRST FERMI LARGE AREA TELESCOPE CATALOG OF GAMMA-RAY PULSARS

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Camilo F, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Cominsky L. R, Conrad J, Corbet R, Cutini S, den Hartog P. R, Dermer C. D, de Angelis A, de Luca A, de Palma F, Digel S. W, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Espinoza C, Farnier C, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Fortin P, Frailis M, Freire P. C. C, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giebels B, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Gotthelf E. V, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Gwon C, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Johnston S, Kamae T, Kanbach G, Kaspi V. M, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kramer M, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Livingstone M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Lyne A. G, Madejski G. M, Makeev A, Manchester R. N, Marelli M, Mazziotta M. N, McConville W, McEnery J. E, McGlynn S, Meurer C, Michelson P. F, Mineo T, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Noutsos A, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Ransom S. M, Ray P. S, Razzano M, Rea N, Reimer A, Reimer O, Reposeur T, Ritz S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Schalk T. L, Sellerholm A, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Stappers B. W, Starck J. -L, Striani E, Strickman M. S, Strong A. W, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Theureau G, Thompson D. J, Thorsett S. E, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wang P, Wang N, Watters K, Weltevrede P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES 187 ( 2 ) 460 - 494 2010年04月 [査読有り]

DOI

Scopus

451

被引用数

(Scopus)
DISCOVERY OF PULSED gamma-RAYS FROM PSR J0034-0534 WITH THE FERMI LARGE AREA TELESCOPE: A CASE FOR CO-LOCATED RADIO AND gamma-RAY EMISSION REGIONS

Abdo A. A, Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Camilo F, Caraveo P. A, Carrigan S, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Conrad J, Corbet R, DeCesar M. E, Dermer C. D, Desvignes G, de Angelis A, de Palma F, Digel S. W, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Espinoza C, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Frailis M, Freire P. C. C, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hadasch D, Harding A. K, Hays E, Hobbs G, Horan D, Hughes R. E, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Johnston S, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kramer M, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Garde M. Llena, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Lyne A. G, Makeev A, Manchester R. N, Marelli M, Mazziotta M. N, McConville W, McEnery J. E, McGlynn S, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Noutsos A, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Pierbattista M, Piron F, Porter T. A, Raino S, Rando R, Ransom S. M, Razzano M, Reimer A, Reimer O, Reposeur T, Ripken J, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Stappers B. W, Starck J. -L, Strickman M. S, Suson D. J, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Theureau G, Thompson D. J, Thorsett S. E, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Usher T. L, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wallace E, Wang P, Weltevrede P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 712 ( 2 ) 957 - 963 2010年04月 [査読有り]

DOI

Scopus

54

被引用数

(Scopus)
VLBI Monitoring of 3C 84 (NGC 1275) in Early Phase of the 2005 Outburst

Hiroshi Nagai, Kenta Suzuki, Keiichi Asada, Motoki Kino, Seiji Kameno, Akihiro Doi, Makoto Inoue, Jun Kataoka, Uwe Bach, Tomoya Hirota, Naoko Matsumoto, Mareki Honma, Hideyuki Kobayashi, Kenta Fujisawa

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 62 ( 2 ) L11 - L15 2010年04月 [査読有り]

　概要を見る

Multi-epoch Very Long Baseline Interferometry (VLBI) study of a sub-pc scale jet of 3C 84 is presented. We carried out 14-epoch VLBI observations during 2006-2009 with the Japanese VLBI Network and the VLBI Exploration of Radio Astrometry, immediately following a radio outburst that began in 2005. We confirmed that the outburst was associated with the central similar to 1 pc core, accompanying the emergence of a new component. This is striking evidence of the recurrence of jet activity. The new component became brighter during 2008, in contrast to constant gamma-ray emission that was observed with the Fermi Gamma-ray Space Telescope during the same time. We found that the projected speed of the new component was 0.23c from 2007/297 (2007 October 24) to 2009/114 (2009 April 24). The direction of movement of this component differs from that of the pre-existing component by similar to 40 degrees. This was the first measurement of the kinematics of a sub-pc jet in a gamma-ray active phase. A possible detection of jet deceleration and the jet kinematics in connection with the gamma-ray emission is discussed.

DOI

Scopus

72

被引用数

(Scopus)
OBSERVATIONS OF MILKY WAY DWARF SPHEROIDAL GALAXIES WITH THE FERMI-LARGE AREA TELESCOPE DETECTOR AND CONSTRAINTS ON DARK MATTER MODELS

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, de Angelis A, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Fusco P, Gargano F, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grove J. E, Guillemot L, Guiriec S, Gustafsson M, Harding A. K, Hays E, Horan D, Hughes R. E, Jackson M. S, Jeltema T. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Profumo S, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rodriguez A. Y, Roth M, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Scargle J. D, Schalk T. L, Sellerholm A, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Ylinen T, Ziegler M, Bullock James S, Kaplinghat Manoj, Martinez Gregory D

ASTROPHYSICAL JOURNAL 712 ( 1 ) 147 - 158 2010年03月 [査読有り]

DOI

Scopus

297

被引用数

(Scopus)
OBSERVATION OF SUPERNOVA REMNANT IC 443 WITH THE FERMI LARGE AREA TELESCOPE

Abdo A. A, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Cillis A. N, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Conrad J, Cutini S, Dermer C. D, de Angelis A, de Palma F, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M-H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kuss M, Lande J, Latronico L, Lee S-H, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, Meurer C, Michelson P. F, Mitthumsiri W, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F-W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Strong A. W, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 712 ( 1 ) 459 - 468 2010年03月 [査読有り]

DOI

Scopus

228

被引用数

(Scopus)
FERMI DETECTION DELAYED GeV EMISSION FROM THE SHORT GAMMA-RAY BURST 081024B

Abdo A. A, Ackermann M, Ajello M, Asano K, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Bhat P. N, Bissaldi E, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Briggs M. S, Brigida M, Bruel P, Burgess J. M, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cecchi C, Celik Oe, Chaplin V, Charles E, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Connaughton V, Conrad J, Cutini S, Dermer C. D, de Angelis A, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Fishman G, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Granot J, Grenier I. A, Grondin M-H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Haynes R. H, Hays E, Horan D, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Kippen R. M, Knoedlseder J, Kocevski D, Kocian M. L, Komin N, Kouveliotou C, Kuehn F, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, McBreen S, McEnery J. E, McGlynn S, Meegan C, Meszaros P, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paciesas W. S, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Preece R, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reposeur T, Ripken J, Ritz S, Rochester L. S, Rodriguez A. Y, Roth M, Ryde F, Sadrozinski H. F-W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Schalk T. L, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Stamatikos M, Strickman M. S, Suson D. J, Tagliaferri G, Tajima H, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Toma K, Torres D. F, Tosti G, Tramacere A, Troja E, Uchiyama Y, Usher T. L, van der Horst A. J, Vasileiou V, Vilchez N, Vitale V, von Kienlin A, Waite A. P, Wang P, Wilson-Hodge C, Winer B. L, Wood K. S, Wu X. F, Yamazaki R, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 712 ( 1 ) 558 - 564 2010年03月 [査読有り]

DOI

Scopus

62

被引用数

(Scopus)
Spectrum of the Isotropic Diffuse Gamma-Ray Emission Derived from First-Year Fermi Large Area Telescope Data

abdo A. A, Ackermann M, Ajello M, Atwood W. B, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Conrad J, Cutini S, Dermer C. D, de Angelis A, de Palma F, Digel S. W, Di Bernardo G, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gaggero D, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Gustafsson M, Hanabata Y, Harding A. K, Hayashida M, Hughes R. E, Itoh R, Jackson M. S, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kuehn F, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, McConville W, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sellerholm A, Sgro C, Shaw M. S, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Strickman M. S, Strong A. W, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

PHYSICAL REVIEW LETTERS 104 ( 10 ) 2010年03月 [査読有り]

DOI

Scopus

480

被引用数

(Scopus)
Fermi large area telescope search for photon lines from 30 to 200 GeV and dark matter implications

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, S. Carrigan, J. M. Casandjian, C. Cecchi, Ö Çelik, A. Chekhtman, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, C. D. Dermer, A. De Angelis, F. De Palma, S. W. Digel, E. Do Couto E Silva, P. S. Drell, A. Drlica-Wagner, R. Dubois, D. Dumora, Y. Edmonds, R. Essig, C. Farnier, C. Favuzzi, S. J. Fegan, W. B. Focke, P. Fortin, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, J. E. Grove, L. Guillemot, S. Guiriec, M. Gustafsson, D. Hadasch, A. K. Harding, D. Horan, R. E. Hughes, M. S. Jackson, G. Jóhannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, M. Llena Garde, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, A. Makeev, M. N. Mazziotta, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte

Physical Review Letters 104 ( 9 ) 2010年03月

　概要を見る

Dark matter (DM) particle annihilation or decay can produce monochromatic γ rays readily distinguishable from astrophysical sources. γ-ray line limits from 30 to 200 GeV obtained from 11 months of Fermi Large Area Space Telescope data from 20-300 GeV are presented using a selection based on requirements for a γ-ray line analysis, and integrated over most of the sky. We obtain γ-ray line flux upper limits in the range 0.6-4.5×10-9cm-2s-1, and give corresponding DM annihilation cross-section and decay lifetime limits. Theoretical implications are briefly discussed. © 2010 The American Physical Society.

DOI

Scopus

243

被引用数

(Scopus)
PSR J1907+0602: A RADIO-FAINT GAMMA-RAY PULSAR POWERING A BRIGHT TeV PULSAR WIND NEBULA

Abdo A. A, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Camilo F, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Cominsky L. R, Conrad J, Cutini S, de Angelis A, de Palma F, Digel S. W, Dingus B. L, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Freire P. C. C, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hays E, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Johnston S, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Marelli M, Mazziotta M. N, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paneque D, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Ray P. S, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Roberts M. S. E, Rochester L. S, Rodriguez A. Y, Ro'mani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Theureau G, Thompson D. J, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wang P, Watters K, Winer B. L, Wolff M. T, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 711 ( 1 ) 64 - 74 2010年03月 [査読有り]

DOI

Scopus

88

被引用数

(Scopus)
Gamma-Ray Emission from the Shell of Supernova Remnant W44 Revealed by the Fermi LAT

Abdo A. A, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Cominsky L. R, Conrad J, Cutini S, Dermer C. D, de Angelis A, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Espinoza C, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Katsuta J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kramer M, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Lyne A. G, Madejski G. M, Makeev A, Mazziotta M. N, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Noutsos A, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paneque D, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Stappers B. W, Stecker F. W, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Theureau G, Thompson D. J, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yamazaki R, Ylinen T, Ziegler M

SCIENCE 327 ( 5969 ) 1103 - 1106 2010年02月 [査読有り]

DOI

Scopus

247

被引用数

(Scopus)
SPECTRAL PROPERTIES OF BRIGHT FERMI-DETECTED BLAZARS IN THE GAMMA-RAY BAND

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Carrigan S, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, Dermer C. D, de Angelis A, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Harding A. K, Hartman R. C, Hayashida M, Hays E, Healey S. E, Horan D, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, McConville W, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Persic M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Villata M, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 710 ( 2 ) 1271 - 1285 2010年02月 [査読有り]

DOI

Scopus

188

被引用数

(Scopus)
A change in the optical polarization associated with a gamma-ray flare in the blazar 3C 279

NATURE 463 ( 7283 ) 919 - 923 2010年02月 [査読有り]

DOI

Scopus

289

被引用数

(Scopus)
PKS 1502+106: A NEW AND DISTANT GAMMA-RAY BLAZAR IN OUTBURST DISCOVERED BY THE FERMI LARGE AREA TELESCOPE

ASTROPHYSICAL JOURNAL 710 ( 1 ) 810 - 827 2010年02月 [査読有り]

DOI

Scopus

57

被引用数

(Scopus)
FERMI-LAT DISCOVERY OF GeV GAMMA-RAY EMISSION FROM THE YOUNG SUPERNOVA REMNANT CASSIOPEIA A

Abdo A. A, Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Buehler R, Burnett T. H, Busetto G, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Charles E, Chaty S, Chekhtman A, Cheung C. C, Chiang J, Cillis A. N, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Corbel S, de Palma F, Digel S. W, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Edmonds Y, Farnier C, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Hays E, Harding A. K, Hayashida M, Horan D, Hughes R. E, Jackson M. S, Johnson A. S, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Pohl M, Porter T. A, Raino S, Rando R, Reimer A, Reimer O, Reposeur T, Ritz S, Rodriguez A. Y, Romani R. W, Roth M, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spinelli P, Strickman M. S, Suson D. J, Tajima H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Thorsett S. E, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yamazaki R, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL LETTERS 710 ( 1 ) L92 - L97 2010年02月 [査読有り]

DOI

Scopus

166

被引用数

(Scopus)
FERMI OBSERVATIONS OF CASSIOPEIA AND CEPHEUS: DIFFUSE GAMMA-RAY EMISSION IN THE OUTER GALAXY

Abdo A. A, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Conrad J, Dermer C. D, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gehrels N, Germani S, Giavitto G, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Harding A. K, Hayashida M, Horan D, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Paneque D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Rodriguez A. Y, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Sgro C, Siskind E. J, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Strickman M. S, Strong A. W, Suson D. J, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 710 ( 1 ) 133 - 149 2010年02月 [査読有り]

DOI

Scopus

194

被引用数

(Scopus)
DETECTION OF GAMMA-RAY EMISSION FROM THE STARBURST GALAXIES M82 AND NGC 253 WITH THE LARGE AREA TELESCOPE ON FERMI

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Dermer C. D, de Angelis A, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Foschini L, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, McConville W, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sander A, Parkinson P, M. Saz, Scargle J. D, Sellerholm A, Sgro C, Shaw M. S, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Strong A. W, Suson D. J, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL LETTERS 709 ( 2 ) L152 - L157 2010年02月 [査読有り]

DOI

Scopus

211

被引用数

(Scopus)
X-ray Polarimetry Small Satellite TSUBAME

Toizumi, T, Enomoto, Usui, R, Nakamori, T, Yatsu, Y, Kawai, N, Kataoka, J, Omagari, K, Nishida, J, Inagawa, S, Matsunaga, S

Proceedings of the 3rd Suzaku Conference 444 - 445 2010年02月
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE CRAB PULSAR AND NEBULA

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Caliandro G. A, Cameron R. A, Camilo F, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Cominsky L. R, Conrad J, Dermer C. D, de Angelis A, de Luca A, de Palma F, Digel S. W, Silva E. do Couto e, Drell P. S, Dubois R, Dumora D, Espinoza C, Farnier C, Favuzzi C, Fegan S. J, Ferrara E. C, Focke W. B, Frailis M, Freire P. C. C, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Johnston S, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kramer M, Kuehn F, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Lyne A. G, Makeev A, Marelli M, Mazziotta M. N, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Noutsos A, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Pierbattista M, Piron F, Porter T. A, Raino S, Rando R, Ray P. S, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Stappers B. W, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Theureau G, Thompson D. J, Thorsett S. E, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Van Etten A, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wallace E, Wang P, Watters K, Weltevrede P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 708 ( 2 ) 1254 - 1267 2010年01月 [査読有り]

DOI

Scopus

273

被引用数

(Scopus)
FERMI OBSERVATIONS OF THE VERY HARD GAMMA-RAY BLAZAR PG 1553+113

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, Dermer C. D, de Angelis A, de Palma F, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Horan D, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, McConville W, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Shaw M. S, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 708 ( 2 ) 1310 - 1320 2010年01月 [査読有り]

DOI

Scopus

50

被引用数

(Scopus)
GAMMA-RAY AND RADIO PROPERTIES OF SIX PULSARS DETECTED BY THE FERMI LARGE AREA TELESCOPE

Weltevrede P, Abdo A. A, Ackermann M, Ajello M, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Camilo F, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Cominsky L. R, Conrad J, Cutini S, Dermer C. D, Desvignes G, de Angelis A, de Luca A, de Palma F, Digel S. W, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Freire P. C. C, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hays E, Hobbs G, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Johnston S, Kamae T, Katagiri H, Kataoka J, Kawai N, Keith M, Kerr M, Knoedlseder J, Kocian M. L, Kramer M, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Lyne A. G, Makeev A, Manchester R. N, Mazziotta M. N, McEnery J. E, McGlynn S, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Ransom S. M, Razzano M, Rea N, Reimer A, Reimer O, Reposeur T, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Stappers B. W, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Theureau G, Thompson D. J, Thorsett S. E, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wang P, Wang N, Watters K, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 708 ( 2 ) 1426 - 1441 2010年01月 [査読有り]

DOI

Scopus

53

被引用数

(Scopus)
The Polarized Gamma-Ray Observer, PoGOLite

TAKAHASHI Hiromitsu, MATSUOKA Masayuki, UMEKI Yudai, YOSHIDA Hiroaki, TANAKA Takuya, MIZUNO Tsunefumi, FUKAZAWA Yasushi, KAMAE Tuneyoshi, MADEJSKI Grzegorz, TAJIMA Hiroyasu, KISS Mózsi, KLAMRA Wlodzimierz, LARSSON Stefan, BETTOLO Cecilia MARINI, PEARCE Mark, RYDE Felix, RYDSTRÖM Stefan, KURITA Kohei, KANAI Yoshikazu, ARIMOTO Makoto, UENO Masaru, KATAOKA Jun, KAWAI Nobuyuki, AXELSSON Magnus, HJALMARSDOTTER Linnea, BOGAERT Gilles, GUNJI Shuichi, KATSUTA Jun'ichiro, TAKAHASHI Tadayuki, VARNER Gary, YUASA Takayuki

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN 8 ( 27 ) Pm_1 - Pm_5 2010年

　概要を見る

The Polarized Gamma-ray Observer, PoGOLite, is a balloon experiment with the capability of detecting 10% polarization from a 200 mCrab celestial object in the energy-range 25–80 keV. During a beam test at KEK-PF in 2008, 19 detector units and one anti-coincidence detector were assembled, and a 50 keV X-ray beam with a polarization degree of ∼90% was irradiated at the center unit. Signals from all 20 units were fed into flight-version electronics consisting of six circuit boards (four waveform digitizer boards, one digital I/O board and one router board) and one microprocessor (SpaceCube), which communicate using a SpaceWire interface. One digitizer board, which can associate up to 8 detectors, outputs a trigger signal. The digital I/O board handles the trigger and returns a data acquisition request if there is no veto signal (upper or pulse-shape discriminators) from any detector unit. This data acquisition system worked well, and the modulation factor was successfully measured to be ∼34%. These results confirmed the capabilities of the data-acquisition system for a "pathfinder" flight planned in 2010.

DOI CiNii
Soft Gamma-ray Detector for the ASTRO-H Mission

Hiroyasu Tajima, Roger Blandford, Teruaki Enoto, Yasushi Fukazawa, Kirk Gilmore, Tuneyoshi Kamae, Jun Kataoka, Madoka Kawaharada, Motohide Kokubun, Philippe Laurent, Francois Lebrun, Olivier Limousin, Greg Madejski, Kazuo Makishima, Tsunefumi Mizuno, Kazuhiro Nakazawa, Masanori Ohno, Masayuki Ohta, Goro Sato, Rie Sato, Hiromitsu Takahashi, Tadayuki Takahashi, Takaaki Tanaka, Makoto Tashiro, Yukikatsu Terada, Yasunobu Uchiyama, Shin Watanabe, Kazutaka Yamaoka, Daisuke Yonetoku

SPACE TELESCOPES AND INSTRUMENTATION 2010: ULTRAVIOLET TO GAMMA RAY 7732 2010年 [査読有り]

　概要を見る

ASTRO-H is the next generation JAXA X-ray satellite, intended to carry instruments with broad energy coverage and exquisite energy resolution. The Soft Gamma-ray Detector (SGD) is one of ASTRO-H instruments and will feature wide energy band (40-600 keV) at a background level 10 times better than the current instruments on orbit. SGD is complimentary to ASTRO-H's Hard X-ray Imager covering the energy range of 5-80 keV. The SGD achieves low background by combining a Compton camera scheme with a narrow field-of-view active shield where Compton kinematics is utilized to reject backgrounds. The Compton camera in the SGD is realized as a hybrid semiconductor detector system which consists of silicon and CdTe (cadmium telluride) sensors. Good energy resolution is afforded by semiconductor sensors, and it results in good background rejection capability due to better constraints on Compton kinematics. Utilization of Compton kinematics also makes the SGD sensitive to the gamma-ray polarization, opening up a new window to study properties of gamma-ray emission processes. The ASTRO-H mission is approved by ISAS/JAXA to proceed to a detailed design phase with an expected launch in 2014. In this paper, we present science drivers and concept of the SGD instrument followed by detailed description of the instrument and expected performance.

DOI

Scopus

59

被引用数

(Scopus)
Swift and fermi observations of the early afterglow of the short gamma-ray burst 090510

M. De Pasquale, P. Schady, N. P.M. Kuin, M. J. Page, P. A. Curran, S. Zane, S. R. Oates, S. T. Holland, A. A. Breeveld, E. A. Hoversten, G. Chincarini, D. Grupe, A. A. Abdo, M. Ackermann, M. Ajello, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, M. G. Baring, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, E. Bissaldi, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. S. Briggs, M. Brigida, P. Bruel, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, S. Carrigan, J. M. Casandjian, C. Cecchi, Ö Çelik, A. Chekhtman, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, V. Connaughton, J. Conrad, C. D. Dermer, A. De Angelis, F. De Palma, B. L. Dingus, E. Do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, G. Fishman, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, J. Granot, J. Greiner, I. A. Grenier, J. E. Grove, L. Guillemot, S. Guiriec, A. K. Harding, M. Hayashida, E. Hays, D. Horan, R. E. Hughes, M. S. Jackson, G. Jóhannesson, A. S. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, R. M. Kippen, J. Knödlseder, D. Kocevski, M. Kuss

Astrophysical Journal Letters 709 ( 2 PART 2 ) 2010年

　概要を見る

We present the observations of GRB090510 performed by the Fermi Gamma-Ray Space Telescope and the Swift observatory. This is a bright, short burst that shows an extended emission detected in the GeV range. Furthermore, its optical emission initially rises, a feature so far observed only in long bursts, while the X-ray flux shows an initial shallow decrease, followed by a steeper decay. This exceptional behavior enables us to investigate the physical properties of the gamma-ray burst outflow, poorly known in short bursts. We discuss internal and external shock models for the broadband energy emission of this object. © 2010. The American Astronomical Society. All rights reserved..

DOI

Scopus

157

被引用数

(Scopus)
Discovery of very high energy gamma rays from PKS 1424+240 and multiwavelength constraints on ITS redshift

V. A. Acciari, E. Aliu, T. Arlen, T. Aune, M. Bautista, M. Beilicke, W. Benbow, M. Böttcher, D. Boltuch, S. M. Bradbury, J. H. Buckley, V. Bugaev, K. Byrum, A. Cannon, A. Cesarini, Y. C. Chow, L. Ciupik, P. Cogan, W. Cui, C. Duke, A. Falcone, J. P. Finley, G. Finnegan, L. Fortson, A. Furniss, N. Galante, D. Gall, G. H. Gillanders, S. Godambe, J. Grube, R. Guenette, G. Gyuk, D. Hanna, J. Holder, C. M. Hui, T. B. Humensky, P. Kaaret, N. Karlsson, M. Kertzman, D. Kieda, A. Konopelko, H. Krawczynski, F. Krennrich, M. J. Lang, S. Lebohec, G. Maier, S. McArthur, A. McCann, M. McCutcheon, J. Millis, P. Moriarty, T. Nagai, R. A. Ong, A. N. Otte, D. Pandel, J. S. Perkins, A. Pichel, M. Pohl, J. Quinn, K. Ragan, L. C. Reyes, P. T. Reynolds, E. Roache, H. J. Rose, M. Schroedter, G. H. Sembroski, G. Demet Senturk, A. W. Smith, D. Steele, S. P. Swordy, M. Theiling, S. Thibadeau, A. Varlotta, V. V. Vassiliev, S. Vincent, R. G. Wagner, S. P. Wakely, J. E. Ward, T. C. Weekes, A. Weinstein, T. Weisgarber, D. A. Williams, S. Wissel, M. Wood, B. Zitzer, A. A. Abdo, M. Ackermann, M. Ajello, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland

Astrophysical Journal Letters 708 ( 2 PART 2 ) 2010年

　概要を見る

We report the first detection of very high energy83Gamma-ray emission above 100 GeV. (VHE) gamma-ray emission above 140 GeV from PKS1424+240, a BL Lac object with an unknown redshift. The photon spectrum above 140 GeV measured by VERITAS is well described by a power law with a photon index of 3.8 0.5stat 0.3syst and a flux normalization at 200 GeV of (5.1 0.9stat 0.5syst) × 10-11 TeV -1 cm-2 s-1, where stat and syst denote the statistical and systematical uncertainties, respectively. The VHE flux is steady over the observation period between MJD 54881 and 55003 (from 2009 February 19 to June 21). Flux variability is also not observed in contemporaneous high-energy observations with the Fermi Large Area Telescope. Contemporaneous X-ray and optical data were also obtained from the Swift XRT and MDM observatory, respectively. The broadband spectral energy distribution is well described by a one-zone synchrotron self-Compton model favoring a redshift of less than 0.1. Using the photon index measured with Fermi in combination with recent extragalactic background light absorption models it can be concluded from the VERITAS data that the redshift of PKS 1424+240 is less than 0.66. © 2010. The American Astronomical Society. All rights reserved.

DOI

Scopus

82

被引用数

(Scopus)
Observations of the large magellanic cloud with fermi

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, C. Cecchi, Ö Çelik, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, S. Cutini, C. D. Dermer, A. De Angelis, F. De Palma, S. W. Dige, E. Do Couto E Silva, P. S. Drel, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, W. B. Focke, P. Fortin, M. Frailis, Y. Fukazawa, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, G. Giavitto, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, E. V. Gotthelf, I. A. Grenier, M. H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, D. Horan, R. E. Hughes, M. S. Jackson, P. Jean, G. Jóhannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knödlseder, M. L. Kocian, M. Kuss, J. Lande, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev

Astronomy and Astrophysics 512 ( 13 ) 2010年

　概要を見る

Context.The Large Magellanic Cloud (LMC) is to date the only normal external galaxy that has been detected in high-energy gamma rays. Highenergy gamma rays trace particle acceleration processes and gamma-ray observations allow the nature and sites of acceleration to be studied. Aims.We characterise the distribution and sources of cosmic rays in the LMC from analysis of gamma-ray observations. Methods.We analyse 11 months of continuous sky-survey observations obtained with the Large Area Telescope aboard the Fermi Gamma-Ray Space Telescope and compare it to tracers of the interstellar medium and models of the gamma-ray sources in the LMC. Results.The LMC is detected at 33s significance. The integrated >100 MeV photon flux of the LMC amounts to (2.6 ± 0.2) × 10-7 ph cm-2 s-1 which corresponds to an energy flux of (1.6 ± 0.1) × 10-10 erg cm -2 s-1, with additional systematic uncertainties of < 16%. The analysis reveals the massive star forming region 30 Doradus as a bright source of gamma-ray emission in the LMC in addition to fainter emission regions found in the northern part of the galaxy. The gamma-ray emission from the LMC shows very little correlation with gas density and is rather correlated to tracers of massive star forming regions. The close confinement of gamma-ray emission to star forming regions suggests a relatively short GeV cosmic-ray proton diffusion length. Conclusions. The close correlation between cosmic-ray density and massive star tracers supports the idea that cosmic rays are accelerated in massive star forming regions as a result of the large amounts of kinetic energy that are input by the stellar winds and supernova explosions of massive stars into the interstellar medium. © ESO 2010.

DOI

Scopus

135

被引用数

(Scopus)
The discovery of γ-ray emission from the blazar RGBJ0710+591

V. A. Acciari, E. Aliu, T. Arlen, T. Aune, M. Bautista, M. Beilicke, W. Benbow, M. Böttcher, D. Boltuch, S. M. Bradbury, J. H. Buckley, V. Bugaev, K. Byrum, A. Cannon, A. Cesarini, L. Ciupik, W. Cui, R. Dickherber, C. Duke, A. Falcone, J. P. Finley, G. Finnegan, L. Fortson, A. Furniss, N. Galante, D. Gall, K. Gibbs, G. H. Gillanders, S. Godambe, J. Grube, R. Guenette, G. Gyuk, D. Hanna, J. Holder, C. M. Hui, T. B. Humensky, A. Imran, P. Kaaret, N. Karlsson, M. Kertzman, D. Kieda, A. Konopelko, H. Krawczynski, F. Krennrich, M. J. Lang, A. Lamerato, S. Lebohec, G. Maier, S. McArthur, A. McCann, M. McCutcheon, P. Moriarty, R. Mukherjee, R. A. Ong, A. N. Otte, D. Pandel, J. S. Perkins, D. Petry, A. Pichel, M. Pohl, J. Quinn, K. Ragan, L. C. Reyes, P. T. Reynolds, E. Roache, H. J. Rose, P. Roustazadeh, M. Schroedter, G. H. Sembroski, G. Demet Senturk, A. W. Smith, D. Steele, S. P. Swordy, G. Tešić, M. Theiling, S. Thibadeau, A. Varlotta, V. V. Vassiliev, S. Vincent, R. G. Wagner, S. P. Wakely, J. E. Ward, T. C. Weekes, A. Weinstein, T. Weisgarber, D. A. Williams, S. Wissel, M. Wood, B. Zitzer, M. Ackermann, M. Ajello, E. Antolini, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford

Astrophysical Journal Letters 715 ( 1 PART 2 ) 2010年

　概要を見る

The high-frequency-peaked BL Lacertae object RGBJ0710+591 was observed in the very high-energy (VHE; E > 100GeV) wave band by the VERITAS array of atmospheric Cherenkov telescopes. The observations, taken between 2008 December and 2009 March and totaling 22.1 hr, yield the discovery of VHE gamma rays from the source. RGBJ0710+591 is detected at a statistical significance of 5.5 standard deviations (5.5σ) above the background, corresponding to an integral flux of (3.9 ± 0.8) × 10-12 cm-2 s-1 (3% of the Crab Nebula's flux) above 300GeV. The observed spectrum can be fit by a power law from 0.31 to 4.6TeV with a photon spectral index of 2.69 ± 0.26stat ± 0.20sys. These data are complemented by contemporaneous multiwavelength data from the Fermi Large Area Telescope, the Swift X-ray Telescope, the Swift Ultra-Violet and Optical Telescope, and the Michigan-Dartmouth-MIT observatory. Modeling the broadband spectral energy distribution (SED) with an equilibrium synchrotron self-Compton model yields a good statistical fit to the data. The addition of an external-Compton component to the model does not improve the fit nor brings the system closer to equipartition. The combined Fermi and VERITAS data constrain the properties of the high-energy emission component of the source over 4 orders of magnitude and give measurements of the rising and falling sections of the SED. © 2010 The American Astronomical Society. All rights reserved.

DOI

Scopus

81

被引用数

(Scopus)
X-ray-emitting GHz-peaked-spectrum galaxies: Testing a dynamical-radiative model with broadband spectra

L. Ostorero, R. Moderski, Stawarz, A. Diaferio, I. Kowalska, C. C. Cheung, J. Kataoka, M. C. Begelman, S. J. Wagner

Astrophysical Journal 715 ( 2 ) 1071 - 1093 2010年

　概要を見る

In a dynamical-radiative model we recently developed to describe the physics of compact, GHz-peaked-spectrum (GPS) sources, the relativistic jets propagate across the inner, kpc-sized region of the host galaxy, while the electron population of the expanding lobes evolves and emits synchrotron and inverse-Compton (IC) radiation. Interstellar-medium gas clouds engulfed by the expanding lobes, and photoionized by the active nucleus, are responsible for the radio spectral turnover through free-free absorption (FFA) of the synchrotron photons. The model provides a description of the evolution of the spectral energy distribution (SED) of GPS sources with their expansion, predicting significant and complex high-energy emission, from the X-ray to the γ-ray frequency domain. Here, we test this model with the broadband SEDs of a sample of 11 X-ray-emitting GPS galaxies with compact-symmetric-object morphology, and show that (1) the shape of the radio continuum at frequencies lower than the spectral turnover is indeed well accounted for by the FFA mechanism and (2) the observed X-ray spectra can be interpreted as non-thermal radiation produced via IC scattering of the local radiation fields off the lobe particles, providing a viable alternative to the thermal, accretion-disk-dominated scenario. We also show that the relation between the hydrogen column densities derived from the X-ray (N H) and radio (N HI) data of the sources is suggestive of a positive correlation, which, if confirmed by future observations, would provide further support to our scenario of high-energy emitting lobes. © 2010. The American Astronomical Society. All rights reserved.

DOI

Scopus

47

被引用数

(Scopus)
Constraints on cosmological dark matter annihilation from the Fermi-LAT isotropic diffuse gamma-ray measurement

A. A. Abdo, M. Ackermann, M. Ajello, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, S. Carrigan, J. M. Casandjian, C. Cecchi, Ö Çelik, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, S. Cutini, C. D. Dermer, A. De Angelis, F. De Palma, S. W. Digel, E. Do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, C. Farnier, C. Favuzzi, S. J. Fegan, W. B. Focke, P. Fortin, M. Frailis, Y. Fukazawa, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, J. E. Grove, L. Guillemot, S. Guiriec, M. Gustafsson, D. Hadasch, A. K. Harding, D. Horan, R. E. Hughes, A. S. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, M. Llena Garde, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, A. Makeev, M. N. Mazziotta, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris

Journal of Cosmology and Astroparticle Physics 2010 ( 4 ) 2010年

　概要を見る

The first published Fermi large area telescope (Fermi-LAT) measurement of the isotropic diffuse gamma-ray emission is in good agreement with a single power law, and is not showing any signature of a dominant contribution from dark matter sources in the energy range from 20 to 100 GeV. We use the absolute size and spectral shape of this measured flux to derive cross section limits on three types of generic dark matter candidates: annihilating into quarks, charged leptons and monochromatic photons. Predicted gamma-ray fluxes from annihilating dark matter are strongly affected by the underlying distribution of dark matter, and by using different available results of matter structure formation we assess these uncertainties. We also quantify how the dark matter constraints depend on the assumed conventional backgrounds and on the Universe's transparency to high-energy gamma-rays. In reasonable background and dark matter structure scenarios (but not in all scenarios we consider) it is possible to exclude models proposed to explain the excess of electrons and positrons measured by the Fermi-LAT and PAMELA experiments. Derived limits also start to probe cross sections expected from thermally produced relics (e.g. in minimal supersymmetry models) annihilating predominantly into quarks. For the monochromatic gamma-ray signature, the current measurement constrains only dark matter scenarios with very strong signals. © 2010 IOP Publishing Ltd and SISSA.

DOI

Scopus

181

被引用数

(Scopus)
Constraints on dark matter annihilation in clusters of galaxies with the Fermi large area telescope

M. Ackermann, M. Ajello, A. Allafort, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, T. J. Brandt, J. Bregeon, M. Brigida, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, S. Carrigan, J. M. Casandjian, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, A. D. Angelis, F. De Palma, E. Do Couto E Silva, P. S. Drell, A. Drlica-Wagner, R. Dubois, D. Dumora, Y. Edmonds, C. Farnier, C. Favuzzi, S. J. Fegan, M. Frailis, Y. Fukazawa, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, S. Guiriec, M. Gustafsson, A. K. Harding, M. Hayashida, D. Horan, R. E. Hughes, T. E. Jeltema, G. Jóhannesson, A. S. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, S. H. Lee, M. Llena Garde, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. N. Mazziotta, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris, E. Nuss, M. Ohno, T. Ohsugi, N. Omodei, E. Orlando

Journal of Cosmology and Astroparticle Physics 2010 ( 5 ) 2010年

　概要を見る

Nearby clusters and groups of galaxies are potentially bright sources of high-energy gamma-ray emission resulting from the pair-annihilation of dark matter particles. However, no significant gamma-ray emission has been detected so far from clusters in the first 11 months of observations with the Fermi Large Area Telescope. We interpret this non-detection in terms of constraints on dark matter particle properties. In particular for leptonic annihilation final states and particle masses greater than ∼ 200 GeV, gamma-ray emission from inverse Compton scattering of CMB photons is expected to dominate the dark matter annihilation signal from clusters, and our gamma-ray limits exclude large regions of the parameter space that would give a good fit to the recent anomalous Pamela and Fermi-LAT electron-positron measurements. We also present constraints on the annihilation of more standard dark matter candidates, such as the lightest neutralino of supersymmetric models. The constraints are particularly strong when including the fact that clusters are known to contain substructure at least on galaxy scales, increasing the expected gamma-ray flux by a factor of ∼ 5 over a smooth-halo assumption. We also explore the effect of uncertainties in cluster dark matter density profiles, finding a systematic uncertainty in the constraints of roughly a factor of two, but similar overall conclusions. In this work, we focus on deriving limits on dark matter models; a more general consideration of the Fermi-LAT data on clusters and clusters as gamma-ray sources is forthcoming. © 2010 IOP Publishing Ltd and SISSA.

DOI

Scopus

162

被引用数

(Scopus)
In-orbit performance of avalanche photodiode as radiation detector on-board a pico-satellite Cute-1.7+APD II

T. Toizumi, Y. Yatsu, T. Nakamori, J. Kataoka, Y. Tsubuku, Y. Kuramoto, T. Enomoto, R. Usui, N. Kawai, K. Akiyama, S. Inagawa, H. Ashida, K. Omagari, N. Miyashita, S. Matsunaga, Y. Ishikawa, Y. Matsunaga, N. Kawabata

HIGH ENERGY, OPTICAL, AND INFRARED DETECTORS FOR ASTRONOMY IV 7742 2010年 [査読有り]

　概要を見る

Cute-1.7+APD II is the third pico-satellite developed by students at the Tokyo Institute of Technology. One of the primary goals of the mission is to validate the use of avalanche photodiodes (APDs) as a radiation detector for the first time in a space experiment. The satellite was successfully launched by an ISRO PSLV-C9 rocket in Apr 2008 and has since been in operation for more than 20 months. Cute-1.7+APD II carries two reverse-type APDs to monitor the distribution of low energy particles down to 9.2 keV trapped in a Low Earth Orbit (LEO), including South Atlantic Anomaly (SAA) as well as aurora bands. We present the design parameters and various preflight tests of the APDs prior to launch, particularly, the high counting response and active gain control system for the Cute-1.7+APD II mission. Examples of electron/proton distribution, obtained in continuous 12-hour observations, will be presented to demonstrate the initial flight performance of the APDs in orbit.

DOI

Scopus
A Thermal-Neutron Detector with a Phoswich System of LiCaAlF6 and BGO Crystal Scintillators onboard PoGOLite

Takahashi H, Yonetani M, Matsuoka M, Mizuno T, Fukazawa Y, Yanagida T, Fujimoto Y, Yokota Y, Yoshikawa A, Kawaguchi N, Ishizu S, Fukuda K, Suyama T, Watanabe K, Tajima H, Kanai Y, Kawai N, Kataoka J, Katsuta J, Takahashi T, Gunji S, Axelsson M, Jackson M, Kiss M, Klamra W, Kole M, Larsson S, Mallol P, Pearce M, Ryde F, Rydstrom S, Olofsson G, Floren H-G, Kamae T, Madejski G, Varner G, IEEE

2010 Ieee Nuclear Science Symposium Conference Record (Nss/mic) 32 - 37 2010年 [査読有り]
Development of BGO active shield for the ASTRO-H soft Gamma-ray Detector

Hanabata Y, Fukazawa Y, Yamaoka K, Tajima H, Kataoka J, Nakazawa K, Takahashi H, Mizuno T, Ohno M, Kokubun M, Takahashi T, Watanabe S, Tashiro M, Terada Y, Sasaki C, Nakajima K, Mizushima T

Proceedings of SPIE - The International Society for Optical Engineering 7732 2010年 [査読有り]

DOI

Scopus

1

被引用数

(Scopus)
Hard X-ray and gamma-ray detector for ASTRO-H based on Si and CdTe imaging sensors

Kokubun M, Watanabe S, Nakazawa K, Tajima H, Fukazawa Y, Takahashi T, Kataoka J, Kamae T, Katagiri H, Madejski G.M, Makishima K, Mizuno T, Ohno M, Sato R, Takahashi H, Tanaka T, Tashiro M, Terada Y, Yamaoka K

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 623 ( 1 ) 425 - 427 2010年 [査読有り]

DOI

Scopus

15

被引用数

(Scopus)
Fermi large area telescope observations of the cosmic-ray induced γ-ray emission of the Earth's atmosphere

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, R. Buehler, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, C. Cecchi, Ö Çelik, E. Charles, A. Chekhtman, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, F. De Palma, S. W. Digel, E. Do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, W. B. Focke, P. Fortin, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, E. Hays, D. Horan, R. E. Hughes, G. Jóhannesson, A. S. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, A. Makeev, M. N. Mazziotta, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris

Physical Review D - Particles, Fields, Gravitation and Cosmology 80 ( 12 ) 2009年12月

　概要を見る

We report on measurements of the cosmic-ray induced γ-ray emission of Earth's atmosphere by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. The Large Area Telescope has observed the Earth during its commissioning phase and with a dedicated Earth limb following observation in September 2008. These measurements yielded ∼6.4×106 photons with energies >100MeV and ∼250 hours total live time for the highest quality data selection. This allows the study of the spatial and spectral distributions of these photons with unprecedented detail. The spectrum of the emission-often referred to as Earth albedo gamma-ray emission-has a power-law shape up to 500GeV with spectral index Γ=2.79±0.06. © 2009 The American Physical Society.

DOI

Scopus

74

被引用数

(Scopus)
FERMI OBSERVATIONS OF TeV-SELECTED ACTIVE GALACTIC NUCLEI

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Conrad J, Cutini S, de Angelis A, de Palma F, di Bernardo G, do Couto e, Silva E, Drell P. S, Drlica-Wagner A, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Finke J, Focke W. B, Fortin P, Foschini L, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giebels B, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Hayashida M, Hays E, Horan D, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson R. P, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, McConville W, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Reyes L. C, Ritz S, Rochester L. S, Rodriguez A. Y, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Schalk T. L, Sellerholm A, Sgro C, Shaw M. S, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Tanaka Y, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 707 ( 2 ) 1310 - 1333 2009年12月 [査読有り]

DOI

Scopus

133

被引用数

(Scopus)
Fermi large area telescope measurements of the diffuse gamma-ray emission at intermediate galactic latitudes

A. A. Abdo, M. Ackermann, M. Ajello, B. Anderson, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, H. Dereli, C. D. Dermer, A. De Angelis, F. De Palma, S. W. Digel, G. Di Bernardo, M. Dormody, E. Do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, C. Farnier, C. Favuzzi, S. J. Fegan, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, D. Gaggero, F. Gargano, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, R. E. Hughes, G. Jóhannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knödlseder, M. L. Kocian, F. Kuehn, M. Kuss, J. Lande, L. Latronico, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. N. Mazziotta, W. McConville

Physical Review Letters 103 ( 25 ) 2009年12月

　概要を見る

The diffuse galactic γ-ray emission is produced by cosmic rays (CRs) interacting with the interstellar gas and radiation field. Measurements by the Energetic Gamma-Ray Experiment Telescope (EGRET) instrument on the Compton Gamma-Ray Observatory indicated excess γ-ray emission 1GeV relative to diffuse galactic γ-ray emission models consistent with directly measured CR spectra (the so-called "EGRET GeV excess"). The Large Area Telescope (LAT) instrument on the Fermi Gamma-Ray Space Telescope has measured the diffuse γ-ray emission with improved sensitivity and resolution compared to EGRET. We report on LAT measurements for energies 100 MeV to 10 GeV and galactic latitudes 10°≤|b|≤20°. The LAT spectrum for this region of the sky is well reproduced by a diffuse galactic γ-ray emission model that is consistent with local CR spectra and inconsistent with the EGRET GeV excess. © 2009 The American Physical Society.

DOI

Scopus

170

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE GAMMA-RAY DETECTION OF THE RADIO GALAXY M87

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Caliandro G. A, Cameron R. A, Cannon A, Caraveo P. A, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Charles E, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Colafrancesco S, Conrad J, Costamante L, Cutini S, Davis D. S, Dermer C. D, de Angelis A, de Palma F, Digel S. W, Donato D, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Edmonds Y, Farnier C, Favuzzi C, Fegan S. J, Finke J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Georganopoulos M, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Horan D, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, McConville W, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sambruna R, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Shaw M. S, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Tanaka T, Taylor G. B, Thayer J. B, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Waite A. P, Wang P, Winer B. L, Wood K. S, Ylinen T, Ziegler M, Harris D. E, Massaro F, Stawarz L

ASTROPHYSICAL JOURNAL 707 ( 1 ) 55 - 60 2009年12月 [査読有り]

DOI

Scopus

164

被引用数

(Scopus)
MULTIWAVELENGTH MONITORING OF THE ENIGMATIC NARROW-LINE SEYFERT 1 PMN J0948+0022 IN 2009 MARCH-JULY

ASTROPHYSICAL JOURNAL 707 ( 1 ) 727 - 737 2009年12月 [査読有り]

DOI

Scopus

93

被引用数

(Scopus)
FERMI OBSERVATIONS OF HIGH-ENERGY GAMMA-RAY EMISSION FROM GRB 080825C

Abdo A. A, Ackermann M, Asano K, Atwood W. B, Axelsson M, Baldini L, Ballet J, B, D. L, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bhat P. N, Bissaldi E, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Briggs M. S, Brigida M, Bruel P, Burnett T. H, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Chaplin V, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Connaughton V, Conrad J, Cutini S, Dermer C. D, de Angelis A, de Palma F, Digel S. W, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Focke W. B, Frailis M, Fukazawa Y, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Gibby L, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Goldstein A, Granot J, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hughes R. E, Johannesson G, Johnson A. S, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocevski D, Komin N, Kouveliotou C, Kuehn F, Kuss M, Latronico L, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, McBreen S, McEnery J. E, McGlynn S, Meegan C, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paciesas W. S, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Preece R, Raino S, Rando R, Razzano M, Razzaque S, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Stamatikos M, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, van der Horst A. J, Vasileiou V, Vilchez N, Vitale V, von Kienlin A, Waite A. P, Wang P, Wilson-Hodge C, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 707 ( 1 ) 580 - 592 2009年12月 [査読有り]

DOI

Scopus

73

被引用数

(Scopus)
Pr:Lu<inf>3</inf>Al<inf>5</inf>O<inf>12</inf> (LuAG) scintillator read-out using UV-enhanced avalanche photodiode

Kei Kamada, Takayuki Yanagida, Jun Kataoka, Akira Yoshikawa, Akihiro Fukabori, Kousuke Tsutsumi, Takanori Endo, Yoshiyuki Usuki

IEEE Nuclear Science Symposium Conference Record 1949 - 1951 2009年12月 [査読有り]

　概要を見る

In this work, energy resolution of Pr:LuAG scintillator was investigated using PMT (Hamamatsu, R7600U), conventional Si-APD (Hamamatsu, S8664-8222) and UV-enhanced Si-APD (Hamamatsu, S8664-8223) at 20 °C hy 662keV gamma-ray irradiation. The APD S8664-8223 has better quantum efficiency (QE) of 45.8% around 310nm of Pr:LuAG emission wavelength than that of S8664-8222 (QE=4.6%@310nm) and R7600U (QE=21%@310nm). Using UV-enhanced APD S8664-8223, Pr:LuAG sample with 2.15 x 2.15 x 10 mm size showed the best energy resolution of 5.7%@662keV at M=10.7. ©2009 IEEE.

DOI

Scopus

3

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE DETECTION OF PULSED gamma-RAYS FROM THE VELA-LIKE PULSARS PSR J1048-5832 AND PSR J2229+6114

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Caliandro G. A, Cameron R. A, Camilo F, Caraveo P. A, Casandjian J. M, Cecchi C, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Conrad J, de Angelis A, de Palma F, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Frailis M, Freire P. C. C, Fukazawa Y, Funk S, Fusco P, Gargano F, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Halpern J, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hobbs G, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Johnston S, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kramer M, Kuehn F, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Lyne A. G, Makeev A, Manchester R. N, Marelli M, Mazziotta M. N, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Noutsos A, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Ransom S. M, Razzano M, Reimer A, Reimer O, Reposeur T, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Stappers B. W, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Theureau G, Thompson D. J, Thorsett S. E, Tibaldo L, Torres D. F, Tosti G, Uchiyama Y, Usher T. L, Van Etten A, Vilchez N, Vitale V, Waite A. P, Wang P, Wang N, Watters K, Weltevrede P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 706 ( 2 ) 1331 - 1340 2009年12月 [査読有り]

DOI

Scopus

42

被引用数

(Scopus)
FERMI OBSERVATIONS OF GRB 090902B: A DISTINCT SPECTRAL COMPONENT IN THE PROMPT AND DELAYED EMISSION

Abdo A. A, Ackermann M, Ajello M, Asano K, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bhat P. N, Bissaldi E, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Briggs M. S, Brigida M, Bruel P, Burgess J. M, Burrows D. N, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Connaughton V, Conrad J, Cutini S, d'Elia V, Dermer C. D, de Angelis A, de Palma F, Digel S. W, Dingus B. L, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Finke J, Fishman G, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gehrels N, Germani S, Giavitto G, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Goldstein A, Granot J, Greiner J, Grenier I. A, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Horan D, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson R. P, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Kippen R. M, Knoedlseder J, Kocevski D, Komin N, Kouveliotou C, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, McBreen S, McEnery J. E, McGlynn S, Meegan C, Meszaros P, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paciesas W. S, Paneque D, Panetta J. H, Pelassa V, Pepe M, Pesce-Rollins M, Petrosian V, Piron F, Porter T. A, Preece R, Raino S, Rando R, Rau A, Razzano M, Razzaque S, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Roming P. W. A, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Schalk T. L, Sgro C, Siskind E. J, Smith P. D, Spinelli P, Stamatikos M, Stecker F. W, Stratta G, Strickman M. S, Suson D. J, Swenson C. A, Tajima H, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Uehara T, Usher T. L, van der Horst A. J, Vasileiou V, Vilchez N, Vitale V, von Kienlin A, Waite A. P, Wang P, Wilson-Hodge C, Winer B. L, Wood K. S, Yamazaki R, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL LETTERS 706 ( 1 ) L138 - L144 2009年11月 [査読有り]

DOI

Scopus

427

被引用数

(Scopus)
FERMI LAT DISCOVERY OF EXTENDED GAMMA-RAY EMISSION IN THE DIRECTION OF SUPERNOVA REMNANT W51C

Abdo A. A, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Buson S, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Conrad J, Cutini S, Dermer C. D, de Angelis A, de Palma F, Digel S. W, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hughes R. E, Jackson M. S, Johannesson G, Johnson A. S, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Katsuta J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Makeev A, Mazziotta M. N, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Paneque D, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Schalk T. L, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Yamazaki R, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL LETTERS 706 ( 1 ) L1 - L6 2009年11月 [査読有り]

DOI

Scopus

245

被引用数

(Scopus)
A limit on the variation of the speed of light arising from quantum gravity effects

Abdo A. A, Ackermann M, Ajello M, Asano K, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Bhat P. N, Bissaldi E, Bloom E. D, Bonamente E, Bonnell J, Borgland A. W, Bouvier A, Bregeon J, Brez A, Briggs M. S, Brigida M, Bruel P, Burgess J. M, Burnett T. H, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Chaplin V, Charles E, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Connaughton V, Conrad J, Cutini S, Dermer C. D, de Angelis A, de Palma F, Digel S. W, Dingus B. L, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Finke J, Fishman G, Focke W. B, Foschini L, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Gibby L, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Granot J, Greiner J, Grenier I. A, Grondin M. -H, Grove J. E, Grupe D, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hoversten E. A, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Kippen R. M, Knoedlseder J, Kocevski D, Kouveliotou C, Kuehn F, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Mazziotta M. N, McBreen S, McEnery J. E, McGlynn S, Meszaros P, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paciesas W. S, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Petrosian V, Piron F, Porter T. A, Preece R, Raino S, Ramirez-Ruiz E, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Roth M, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Schalk T. L, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Stamatikos M, Stecker F. W, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Toma K, Torres D. F, Tosti G, Troja E, Uchiyama Y, Uehara T, Usher T. L, van der Horst A. J, Vasileiou V, Vilchez N, Vitale V, von Kienlin A, Waite A. P, Wang P, Wilson-Hodge C, Winer B. L, Wood K. S, Wu X. F, Yamazaki R, Ylinen T, Ziegler M

NATURE 462 ( 7271 ) 331 - 334 2009年11月 [査読有り]

DOI

Scopus

513

被引用数

(Scopus)
The on-orbit calibration of the Fermi Large Area Telescope

Abdo A. A, Ackermann M, Ajello M, Ampe J, Anderson B, Atwood W. B, Axelsson M, Bagagli R, Baldini L, Ballet J, Barbiellini G, Bartelt J, Bastieri D, Baughman B. M, Bechtol K, Bederede D, Bellardi F, Bellazzini R, Belli F, Berenji B, Bisello D, Bissaldi E, Bloom E. D, Bogaert G, Bogart J. R, Bonamente E, Borgland A. W, Bourgeois P, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Busetto G, Caliandro G. A, Cameron R. A, Campell M, Caraveo P. A, Carius S, Carlson P, Casandjian J. M, Cavazzuti E, Ceccanti M, Cecchi C, Charles E, Chekhtman A, Cheung C. C, Chiang J, Chipaux R, Cillis A. N, Ciprini S, Claus R, Cohen-Tanugi J, Condamoor S, Conrad J, Corbet R, Cutini S, Davis D. S, DeKlotz M, Dermer C. D, de Angelis A, de Palma F, Digel S. W, Dizon P, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Edmonds Y, Fabiani D, Farnier C, Favuzzi C, Ferrara E. C, Ferreira O, Fewtrell Z, Flath D. L, Fleury P, Focke W. B, Fouts K, Frailis M, Freytag D, Fukazawa Y, Funk S, Fusco P, Garganov F, Gasparrini D, Gehrelscao N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Goodman J, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hakimi M, Haller G, Hanabata Y, Hart P. A, Hascall P, Hays E, Huffer M, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kavelaars A, Kelly H, Kerr M, Klamra W, Knoedlseder J, Kocian M. L, Kuehn F, Kuss M, Latronico L, Lavalley C, Leas B, Lee B, Lee S. -H, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Lung D. K, Madejski G. M, Makeev A, Marangelli B, Marchetti M, Massai M. M, May D, Mazzenga G, Mazziotta M. N, McEnery J. E, McGlynn S, Meurer C, Michelson P. F, Minuti M, Mirizzi N, Mitra P, Mitthumsiri W, Mizuno T, Moiseev A. A, Mongelli M, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nelson D, Nilsson L, Nishino S, Nolan P. L, Nuss E, Ohno M, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paccagnella A, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Picozza P, Pinchera M, Piron F, Porter T. A, Raino S, Rando R, Rapposelli E, Raynor W, Razzano M, Reimer A, Reimer O, Reposeur T, Reyes L. C, Ritz S, Robinson S, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sacchetti A, Sadrozinski H. F. -W, Saggini N, Sanchez D, Sander A, Sapozhnikov L, Saxton O. H, Parkinson P, M. Saz, Sellerholm A, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Stephens T. E, Strickman M. S, Strong A. W, Sugizaki M, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Tenze A, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Turri M, Usher T. L, Vilchez N, Virmani N, Vitale V, Wai L. L, Waite A. P, Wang P, Winer B. L, Wood D. L, Wood K. S, Yasuda H, Ylinen T, Ziegler M

ASTROPARTICLE PHYSICS 32 ( 3-4 ) 193 - 219 2009年10月 [査読有り]

DOI

Scopus

161

被引用数

(Scopus)
FERMI LAT OBSERVATIONS OF LS I+61 degrees 303: FIRST DETECTION OF AN ORBITAL MODULATION IN GeV GAMMA RAYS

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Blandford R, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cavazzuti E, Cecchi C, Celik Oe, Charles E, Chaty S, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky L. R, Conrad J, Corbel S, Corbet R, Cutini S, Dermer C. D, de Angelis A, de Luca A, de Palma F, Digel S. W, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dubus G, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hill A. B, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kuehn F, Kuss M, Lande J, Larsson S, Latronico L, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Marelli M, Mazziotta M. N, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Ray P. S, Razzano M, Rea N, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Shaw M. S, Sierpowska-Bartosik A, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Striani E, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL LETTERS 701 ( 2 ) L123 - L128 2009年08月 [査読有り]

DOI

Scopus

158

被引用数

(Scopus)
A Population of Gamma-Ray Millisecond Pulsars Seen with the Fermi Large Area Telescope

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Bignami G. F, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Caliandro G. A, Cameron R. A, Camilo F, Caraveo P. A, Carlson P, Casandjian J. M, Cecchi C, Celik Oe, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Cominsky L. R, Conrad J, Corbet R, Cutini S, Dermer C. D, Desvignes G, de Angelis A, de Luca A, de Palma F, Digel S. W, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Edmonds Y, Farnier C, Favuzzi C, Fegan S. J, Focke W. B, Frailis M, Freire P. C. C, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hobbs G, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Johnston S, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kramer M, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Manchester R. N, Marelli M, Mazziotta M. N, McConville W, McEnery J. E, McLaughlin M. A, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paneque D, Panetta J. H, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Ransom S. M, Ray P. S, Razzano M, Rea N, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Ryde F, Sadrozinski H. F. W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Schalk T. L, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Stappers B. W, Starck J. L, Striani E, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Theureau G, Thompson D. J, Thorsett S. E, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite A. P, Wallace E, Wang P, Watters K, Webb N, Weltevrede P, Winer B. L, Wood K. S, Ylinen T, Ziegler M

SCIENCE 325 ( 5942 ) 848 - 852 2009年08月 [査読有り]

DOI

Scopus

224

被引用数

(Scopus)
Detection of 16 Gamma-Ray Pulsars Through Blind Frequency Searches Using the Fermi LAT

Abdo A. A, Ackermann M, Ajello M, Anderson B, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring M. G, Bastieri D, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Bignami G. F, Blandford R. D, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Celik Oe, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, Dermer C. D, de Angelis A, de Luca A, de Palma F, Digel S. W, Dormody M, do Couto e, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan S. J, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Gwon C, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hughes R. E, Johannesson G, Johnson R. P, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Marelli M, Mazziotta M. N, McConville W, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Norris J. P, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paneque D, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Pierbattista M, Piron F, Porter T. A, Primack J. R, Raino S, Rando R, Ray P. S, Razzano M, Rea N, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Scargle J. D, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. G, Thompson D. J, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Van Etten A, Vasileiou V, Vilchez N, Vitale V, Waite A. P, Wang P, Watters K, Winer B. L, Wolff M. T, Wood K. S, Ylinen T, Ziegler M

SCIENCE 325 ( 5942 ) 840 - 844 2009年08月 [査読有り]

DOI

Scopus

319

被引用数

(Scopus)
PULSED GAMMA-RAYS FROM PSR J2021+3651 WITH THE FERMI LARGE AREA TELESCOPE

Abdo A. A, Ackermann M, Ajello M, Atwood W. B, Baldini L, Ballet J, Barbiellini G, Bastieri D, Battelino M, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bogaert G, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Caliandro G. A, Cameron R. A, Camilo F, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chekhtman A, Chen A. W, Cheung C. C, Chiang J, Ciprini S, Cognard I, Cohen-Tanugi J, Cominsky L. R, Conrad J, Cutini S, Demorest P, Dermer C. D, de Angelis A, de Luca A, de Palma F, Digel S. W, Dormody M, do Couto E, Silva E, Drell P. S, Dubois R, Dumora D, Espinoza C, Farnier C, Favuzzi C, Focke W. B, Frailis M, Freire P. C. C, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Johnston S, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Kiziltan B, Knoedlseder J, Komin N, Kramer M, Kuehn F, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Lyne A. G, Makeev A, Manchester R. N, Marelli M, Mazziotta M. N, McConville W, McEnery J. E, McLaughlin M. A, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Noutsos A, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Ozaki M, Paneque D, Panetta J. H, Parent D, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Ransom S. M, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Ryde F, Sadrozinski H. F. -W, Sanchez D, Parkinson P, M. Saz, Sgro C, Sierpowska-Bartosik A, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Stappers B. W, Starck J. -L, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer J. B, Thayer J. G, Theureau G, Thompson D. J, Thorsett S. E, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Van Etten A, Vilchez N, Vitale V, Waite A. P, Wallace E, Watters K, Weltevrede P, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 700 ( 2 ) 1059 - 1066 2009年08月 [査読有り]

DOI

Scopus

50

被引用数

(Scopus)
FERMI/LARGE AREA TELESCOPE DISCOVERY OF GAMMA-RAY EMISSION FROM A RELATIVISTIC JET IN THE NARROW-LINE QUASAR PMN J0948+0022

ASTROPHYSICAL JOURNAL 699 ( 2 ) 976 - 984 2009年07月 [査読有り]

DOI

Scopus

186

被引用数

(Scopus)
PULSED GAMMA RAYS FROM THE MILLISECOND PULSAR J0030+0451 WITH THE FERMI LARGE AREA TELESCOPE

Abdo A. A, Ackermann M, Atwood W. B, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Battelino M, Baughman B. M, Bechtol K, Bellazzini R, Berenji B, Bloom E. D, Bonamente E, Borgland A. W, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Caliandro G. A, Cameron R. A, Caraveo P. A, Casandjian J. M, Cecchi C, Charles E, Chekhtman A, Cheung C. C, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Cominsky L. R, Conrad J, Cutini S, Dermer C. D, De Angelis A, De Palma F, Digel S. W, Dormody M, Do Couto E, Silva E, Drell P. S, Dubois R, Dumora D, Farnier C, Favuzzi C, Focke W. B, Frailis M, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Hanabata Y, Harding A. K, Hayashida M, Hays E, Hughes R. E, Johannesson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kocian M. L, Komin N, Kuehn F, Kuss M, Lande J, Latronico L, Lee S. -H, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Marelli M, Mazziotta M. N, McConville W, McEnery J. E, Meurer C, Michelson P. F, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Morselli A, Moskalenko I. V, Murgia S, Nolan P. L, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Pancrazi B, Paneque D, Panetta J. H, Parent D, Pepe M, Pesce-Rollins M, Piron F, Porter T. A, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Ryde F, Sadrozinski H. F. -W, Sanchez D, Sander A, Parkinson P, M. Saz, Sgro C, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Strickman M. S, Suson D. J, Tajima H, Takahashi H, Tanaka T, Thayer J. B, Thayer J. G, Theureau G, Thompson D. J, Tibaldo L, Torres D. F, Tosti G, Tramacere A, Uchiyama Y, Usher T. L, Van Etten A, Vilchez N, Vitale V, Waite A. P, Watters K, Webb N, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 699 ( 2 ) 1171 - 1177 2009年07月 [査読有り]

DOI

Scopus

44

被引用数

(Scopus)
SUZAKU WIDE BAND ANALYSIS OF THE X-RAY VARIABILITY OF TeV BLAZAR Mrk 421 IN 2006

Masayoshi Ushio, Takaaki Tanaka, Grzegorz Madejski, Tadayuki Takahashi, Masaaki Hayashida, Jun Kataoka, Daniel Mazin, Stefan Ruegamer, Rie Sato, Masahiro Teshima, Stefan Wagner, Yuichi Yaji

ASTROPHYSICAL JOURNAL 699 ( 2 ) 1964 - 1972 2009年07月 [査読有り]

　概要を見る

We present the results of X-ray observations of the well studied TeV blazar Mrk 421 with the Suzaku satellite in 2006 April 28. During the observation, Mrk 421 was undergoing a large flare and the X-ray flux was variable, decreasing by similar to 50%, from 7.8 x 10(-10) to 3.7 x 10(-10) erg s(-1) cm(-2) in about 6 hr, followed by an increase by similar to 35%. Thanks to the broad bandpass coupled with high sensitivity of Suzaku, we measured the evolution of the spectrum over the 0.4-60 keV band in data segments as short as similar to 1 ks. The data show deviations from a simple power-law model, but also a clear spectral variability. The time-resolved spectra are fitted by a synchrotron model, where the observed spectrum is due to a exponentially cutoff power-law distribution of electrons radiating in uniform magnetic field; this model is preferred over a broken power law. As another scenario, we separate the spectrum into "steady" and "variable" components by subtracting the spectrum in the lowest-flux period from those of other data segments. In this context, the difference ("variable") spectra are all well described by a broken power-law model with photon index Gamma similar to 1.6, breaking at energy epsilon(brk) similar or equal to 3 keV to another photon index Gamma similar to 2.1 above the break energy, differing from each other only by normalization, while the spectrum of the "steady" component is best described by the synchrotron model. We suggest that the rapidly variable component is due to relatively localized shock (Fermi I) acceleration, while the slowly variable ("steady") component is due to the superposition of shocks located at larger distance along the jet, or due to other acceleration process, such as the stochastic acceleration on magnetic turbulence (Fermi II) in the more extended region.

DOI

Scopus

29

被引用数

(Scopus)
FERMI/LARGE AREA TELESCOPE BRIGHT GAMMA-RAY SOURCE LIST

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, D. L. Band, G. Barbiellini, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, G. F. Bignami, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, R. Corbet, L. Costamante, S. Cutini, D. S. Davis, C. D. Dermer, A. de Angelis, A. de Luca, F. de Palma, S. W. Digel, M. Dormody, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, E. C. Ferrara, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, S. E. Healey, D. Horan, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, D. Kocevski, M. L. Kocian, N. Komin, F. Kuehn, M. Kuss, J. Lande, L. Latronico, S. -H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. Marelli, M. N. Mazziotta, W. McConville, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, P. L. Nolan, J. P. Norris, E. Nuss, M. Ohno, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, L. Poupard, S. Raino, R. Rando, P. S. Ray, M. Razzano, N. Rea, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, M. S. Shaw, C. Shrader, A. Sierpowska-Bartosik, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, T. E. Stephens, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, O. Tibolla, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, A. Van Etten, N. Vilchez, V. Vitale, A. P. Waite, E. Wallace, P. Wang, K. Watters, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES 183 ( 1 ) 46 - 66 2009年07月 [査読有り]

　概要を見る

Following its launch in 2008 June, the Fermi Gamma-ray Space Telescope (Fermi) began a sky survey in August. The Large Area Telescope (LAT) on Fermi in three months produced a deeper and better resolved map of the gamma-ray sky than any previous space mission. We present here initial results for energies above 100 MeV for the 205 most significant (statistical significance greater than similar to 10 sigma) gamma-ray sources in these data. These are the best characterized and best localized point-like (i.e., spatially unresolved) gamma-ray sources in the early mission data.

DOI

Scopus

446

被引用数

(Scopus)
FERMI DISCOVERY OF GAMMA-RAY EMISSION FROM NGC 1275

A. A. Abdo, M. Ackermann, M. Ajello, K. Asano, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, A. Celotti, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, L. R. Cominsky, J. Conrad, L. Costamante, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, D. Donato, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, J. Finke, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, M. Georganopoulos, S. Germani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, M. Kadler, T. Kamae, Y. Kanai, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, F. Kuehn, M. Kuss, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. N. Mazziotta, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, A. Y. Rodriguez, R. W. Romani, F. Ryde, H. F. -W. Sadrozinski, R. Sambruna, D. Sanchez, A. Sander, R. Sato, P. M. Saz Parkinson, C. Sgro, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, G. B. Taylor, J. G. Thayer, D. J. Thompson, D. F. Torres, G. Tosti, Y. Uchiyama, T. L. Usher, N. Vilchez, V. Vitale, A. P. Waite, K. S. Wood, T. Ylinen, M. Ziegler, H. D. Aller, M. F. Aller, K. I. Kellermann, Y. Y. Kovalev, Yu. A. Kovalev, M. L. Lister, A. B. Pushkarev

ASTROPHYSICAL JOURNAL 699 ( 1 ) 31 - 39 2009年07月 [査読有り]

　概要を見る

We report the discovery of high-energy (E > 100 MeV) gamma-ray emission from NGC 1275, a giant elliptical galaxy lying at the center of the Perseus cluster of galaxies, based on observations made with the Large Area Telescope (LAT) of the Fermi Gamma-ray Space Telescope. The positional center of the gamma-ray source is only approximate to 3' away from the NGC 1275 nucleus, well within the 95% LAT error circle of approximate to 5'. The spatial distribution of gamma-ay photons is consistent with a point source. The average flux and power-law photon index measured with the LAT from 2008 August 4 to 2008 December 5 are F-gamma = (2.10 +/- 0.23) x 10(-7) ph (>100 MeV) cm(-2) s(-1) and Gamma = 2.17 +/- 0.05, respectively. The measurements are statistically consistent with constant flux during the four-month LAT observing period. Previous EGRET observations gave an upper limit of F-gamma < 3.72 x 10(-8) ph (>100 MeV) cm(-2) s(-1) to the gamma-ray flux from NGC 1275. This indicates that the source is variable on timescales of years to decades, and therefore restricts the fraction of emission that can be produced in extended regions of the galaxy cluster. Contemporaneous and historical radio observations are also reported. The broadband spectrum of NGC 1275 is modeled with a simple one-zone synchrotron/synchrotron self-Compton model and a model with a decelerating jet flow.

DOI

Scopus

174

被引用数

(Scopus)
EARLY FERMI GAMMA-RAY SPACE TELESCOPE OBSERVATIONS OF THE QUASAR 3C 454.3

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, S. Chaty, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, L. Costamante, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, E. do Couto e Silva, D. Donato, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, W. B. Focke, L. Foschini, M. Frailis, L. Fuhrmann, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, M. L. Kocian, F. Kuehn, M. Kuss, L. Latronico, S. -H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, E. Massaro, M. N. Mazziotta, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, R. Rando, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, F. Rahoui, F. Ryde, H. F. -W. Sadrozinski, R. Sambruna, D. Sanchez, A. Sander, P. M. Saz Parkinson, C. Sgro, M. S. Shaw, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, N. Vilchez, M. Villata, V. Vitale, A. P. Waite, B. L. Winer, K. S. Wood, T. Ylinen, J. A. Zensus, M. Ziegler

ASTROPHYSICAL JOURNAL 699 ( 1 ) 817 - 823 2009年07月 [査読有り]

　概要を見る

This is the first report of Fermi Gamma-Ray Space Telescope observations of the quasar 3C 454.3, which has been undergoing pronounced long-term outbursts since 2000. The data from the Large Area Telescope, covering 2008 July 7-October 6, indicate strong, highly variable.-ray emission with an average flux of similar to 3 x 10 (6) photons cm(-2) s(-1), for energies > 100 MeV. The gamma-ray flux is variable, with strong, distinct, symmetrically shaped flares for which the flux increases by a factor of several on a timescale of about 3 days. This variability indicates a compact emission region, and the requirement that the source is optically thin to pair production implies relativistic beaming with Doppler factor delta > 8, consistent with the values inferred from Very Long Baseline Interferometry observations of superluminal expansion (delta similar to 25). The observed gamma-ray spectrum is not consistent with a simple power law, but instead steepens strongly above similar to 2 GeV, and is well described by a broken power law with photon indices of similar to 2.3 and similar to 3.5 below and above the break, respectively. This is the first direct observation of a break in the spectrum of a high-luminosity blazar above 100 MeV, and it is likely direct evidence for an intrinsic break in the energy distribution of the radiating particles. Alternatively, the spectral softening above 2 GeV could be due to gamma-ray absorption via photon-photon pair production on the soft X-ray photon field of the host active galactic nucleus, but such an interpretation would require the dissipation region to be located very close (less than or similar to 100 gravitational radii) to the black hole, which would be inconsistent with the X-ray spectrum of the source.

DOI

Scopus

122

被引用数

(Scopus)
BRIGHT ACTIVE GALACTIC NUCLEI SOURCE LIST FROM THE FIRST THREE MONTHS OF THE FERMI LARGE AREA TELESCOPE ALL-SKY SURVEY

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, A. W. Chen, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, W. Collmar, L. R. Cominsky, J. Conrad, L. Costamante, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, E. C. Ferrara, J. Finke, W. B. Focke, L. Foschini, M. Frailis, L. Fuhrmann, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, S. E. Healey, D. Horan, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, M. Kadler, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knoedlseder, M. L. Kocian, F. Kuehn, M. Kuss, J. Lande, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, E. Massaro, M. N. Mazziotta, W. McConville, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, R. Rando, M. Razzano, S. Razzaque, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, M. S. Shaw, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, G. B. Taylor, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, N. Vilchez, M. Villata, V. Vitale, A. P. Waite, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL 700 ( 1 ) 597 - 622 2009年07月 [査読有り]

　概要を見る

The first three months of sky-survey operation with the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope reveal 132 bright sources at |b| > 10 degrees with test statistic greater than 100 ( corresponding to about 10 sigma). Two methods, based on the CGRaBS, CRATES, and BZCat catalogs, indicate high-confidence associations of 106 of these sources with known active galactic nuclei (AGNs). This sample is referred to as the LAT Bright AGN Sample (LBAS). It contains two radio galaxies, namely, Centaurus A and NGC 1275, and 104 blazars consisting of 58 flat spectrum radio quasars (FSRQs), 42 BL Lac objects, and 4 blazars with unknown classification. Four new blazars were discovered on the basis of the LAT detections. Remarkably, the LBAS includes 10 high-energy-peaked BL Lacs (HBLs), sources which were previously difficult to detect in the GeV range. Another 10 lower-confidence associations are found. Only 33 of the sources, plus two at |b| < 10 degrees, were previously detected with Energetic Gamma-Ray Experiment Telescope( EGRET), probably due to variability. The analysis of the gamma-ray properties of the LBAS sources reveals that the average GeV spectra of BL Lac objects are significantly harder than the spectra of FSRQs. No significant correlation between radio and peak gamma-ray fluxes is observed. Blazar log N-log S distributions and luminosity functions are constructed to investigate the evolution of the different blazar classes, with positive evolution indicated for FSRQs but none for BL Lacs. The contribution of LAT blazars to the total extragalactic gamma-ray intensity is estimated.

DOI

Scopus

378

被引用数

(Scopus)
THE LARGE AREA TELESCOPE ON THE FERMI GAMMA-RAY SPACE TELESCOPE MISSION

Atwood W. B, Abdo A. A, Ackermann M, Althouse W, Anderson B, Axelsson M, Baldini L, Ballet J, B, D. L, Barbiellini G, Bartelt J, Bastieri D, Baughman B. M, Bechtol K, Bederede D, Bellardi F, Bellazzini R, Berenji B, Bignami G. F, Bisello D, Bissaldi E, Blandford R. D, Bloom E. D, Bogart J. R, Bonamente E, Bonnell J, Borgland A. W, Bouvier A, Bregeon J, Brez A, Brigida M, Bruel P, Burnett T. H, Busetto G, Caliandro G. A, Cameron R. A, Caraveo P. A, Carius S, Carlson P, Casandjian J. M, Cavazzuti E, Ceccanti M, Cecchi C, Charles E, Chekhtman A, Cheung C. C, Chiang J, Chipaux R, Cillis A. N, Ciprini S, Claus R, Cohen-Tanugi J, Condamoor S, Conrad J, Corbet R, Corucci L, Costamante L, Cutini S, Davis D. S, Decotigny D, DeKlotz M, Dermer C. D, De Angelis A, Digel S. W, Silva E. Do Couto E, Drell P. S, Dubois R, Dumora D, Edmonds Y, Fabiani D, Farnier C, Favuzzi C, Flath D. L, Fleury P, Focke W. B, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Gentit F. -X, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Grenier I. A, Grondin M. -H, Grove J. E, Guillemot L, Guiriec S, Haller G, Harding A. K, Hart P. A, Hays E, Healey S. E, Hirayama M, Hjalmarsdotter L, Horn R, Hughes R. E, Johannesson G, Johansson G, Johnson A. S, Johnson R. P, Johnson T. J, Johnson W. N, Kamae T, Katagiri H, Kataoka J, Kavelaars A, Kawai N, Kelly H, Kerr M, Klamra W, Knoedlseder J, Kocian M. L, Komin N, Kuehn F, Kuss M, Landriu D, Latronico L, Lee B, Lee S. -H, Lemoine-Goumard M, Lionetto A. M, Longo F, Loparco F, Lott B, Lovellette M. N, Lubrano P, Madejski G. M, Makeev A, Marangelli B, Massai M. M, Mazziotta M. N, McEnery J. E, Menon N, Meurer C, Michelson P. F, Minuti M, Mirizzi N, Mitthumsiri W, Mizuno T, Moiseev A. A, Monte C, Monzani M. E, Moretti E, Morselli A, Moskalenko I. V, Murgia S, Nakamori T, Nishino S, Nolan P. L, Norris J. P, Nuss E, Ohno M, Ohsugi T, Omodei N, Orlando E, Ormes J. F, Paccagnella A, Paneque D, Panetta J. H, Parent D, Pearce M, Pepe M, Perazzo A, Pesce-Rollins M, Picozza P, Pieri L, Pinchera M, Piron F, Porter T. A, Poupard L, Raino S, Rando R, Rapposelli E, Razzano M, Reimer A, Reimer O, Reposeur T, Reyes L. C, Ritz S, Rochester L. S, Rodriguez A. Y, Romani R. W, Roth M, Russell J. J, Ryde F, Sabatini S, Sadrozinski H. F. -W, Sanchez D, Sander A, Sapozhnikov L, Parkinson P, M. Saz, Scargle J. D, Schalk T. L, Scolieri G, Sgro C, Share G. H, Shaw M, Shimokawabe T, Shrader C, Sierpowska-Bartosik A, Siskind E. J, Smith D. A, Smith P. D, Spandre G, Spinelli P, Starck J. -L, Stephens T. E, Strickman M. S, Strong A. W, Suson D. J, Tajima H, Takahashi H, Takahashi T, Tanaka T, Tenze A, Tether S, Thayer J. B, Thayer J. G, Thompson D. J, Tibaldo L, Tibolla O, Torres D. F, Tosti G, Tramacere A, Turri M, Usher T. L, Vilchez N, Vitale V, Wang P, Watters K, Winer B. L, Wood K. S, Ylinen T, Ziegler M

ASTROPHYSICAL JOURNAL 697 ( 2 ) 1071 - 1102 2009年06月 [査読有り]

DOI

Scopus

3508

被引用数

(Scopus)
Performance of a multi-anode photomultiplier employing an ultra bi-alkali photo-cathode and rugged dynodes

T. Toizumi, S. Inagawa, T. Nakamori, J. Kataoka, Y. Tsubuku, Y. Yatsu, T. Shimokawabe, N. Kawai, T. Okada, I. Ohtsu

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 604 ( 1-2 ) 168 - 173 2009年06月 [査読有り]

　概要を見る

We report on the performance testing of a multi-anode photomultiplier (MAPMT), the R8900-200-M16MOD-UBA, newly developed by Hamamatsu Photonics K.K. Although the R8900 series offers the great advantage of a highly sensitive surface (>=-80% of physical area), the quantum efficiency (Q.E.) was relatively low (at up to 20%). This paper describes two substantial changes we have made to the R8900-200-M16MOD-UBA: (1) improving the Q.E. to the 40% level by employing an ultra bi-alkali (UBA) photocathode and (2) constructing a rugged dynode that can withstand vibration for future use in space. We measured each pixel signal at the single photoelectron level and the signals of scintillation photons by using a 16-pixel plastic scintillator array. Thanks to high Q.E., good energy resolution of 29.9% (FWHM) was obtained for 59.5 keV gamma-rays. We also demonstrated tolerance to vibration up to 17 G(rms) in possible launching vehicles. (C) 2009 Elsevier B.V. All rights reserved.

DOI

Scopus

9

被引用数

(Scopus)
Development of a low-noise analog front-end ASIC for APD-PET detectors

M. Koizumi, J. Kataoka, S. Tanaka, H. Ishibashi, N. Kawai, H. Ikeda, Y. Ishikawa, N. Kawabata, Y. Matsunaga, K. Shimizu, H. Kubo

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 604 ( 1-2 ) 327 - 330 2009年06月 [査読有り]

　概要を見る

We report on the development of a front-end ASIC for high spatial resolution PET detectors with time-of-flight capability based on LYSO scintillator arrays coupled with position-sensitive avalanche photodiode (APD) arrays. The ASIC is designed based on the open-IP LSI project led by JAXA and realized in TSMC 0.35-mu m CMOS technology. It consists of an 8-channel charge-sensitive amplifier, band-pass filters, differentiators, pulse-height and timing discriminators, and two-channel time-to-amplitude converters. As a result, energy resolution of 9.7% (FWHM) is obtained at 511 keV, with a time resolution below 970 ps (sigma). We will also report on the current status of developing a second-version ASIC designed to have 32-channel analog circuits with improved time resolution. (C) 2009 Elsevier B.V. All rights reserved.

DOI

Scopus

10

被引用数

(Scopus)
Development of large-area, reverse-type APD-arrays for high-resolution medical imaging

J. Kataoka, M. Koizumi, S. Tanaka, H. Ishibashi, T. Nakamori, N. Kawai, H. Ikeda, Y. Ishikawa, N. Kawabata, Y. Matsunaga, S. Kishimoto, H. Kubo

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 604 ( 1-2 ) 323 - 326 2009年06月 [査読有り]

　概要を見る

Avalanche photodiodes (APD) offer advantages in terms of weak scintillation detection, fast time response, and magnetic field insensitivity. We have developed new types of large-area, reverse-type APD-arrays specifically designed for high-resolution positron emission tomography (PET). Each device has a monolithic 16 x 16 (or 8 x 8) pixel structure with an active area of 1.0 (or 4.0, 0.25) mm(2) for each pixel. An excellent gain uniformity (<= 10%) and low dark noise (<= 0.3 nA) have been achieved, measured at room temperature. Energy resolution of 7.2% (FWHM) was obtained for the direct detection of 5.9 keV X-rays, while 10.2% (FWHM) was obtained for 662 keV gamma-rays when coupled with a LYSO scintillator matrix. An excellent time resolution of 102 ps (FWHM) was obtained for a monolithic, 3 mm phi APD pixel. These results suggest that APD-arrays could be a promising device for future applications in nuclear medicine. (C) 2009 Elsevier B.V. All rights reserved.

DOI

Scopus

21

被引用数

(Scopus)
SIMULTANEOUS OBSERVATIONS OF PKS 2155-304 WITH HESS, FERMI, RXTE, AND ATOM: SPECTRAL ENERGY DISTRIBUTIONS AND VARIABILITY IN A LOW STATE

F. Aharonian, A. G. Akhperjanian, G. Anton, U. Barres de Almeida, A. R. Bazer-Bachi, Y. Becherini, B. Behera, K. Bernloehr, C. Boisson, A. Bochow, V. Borrel, E. Brion, J. Brucker, P. Brun, R. Buehler, T. Bulik, I. Buesching, T. Boutelier, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L. M. Chounet, A. C. Clapson, G. Coignet, M. Dalton, M. K. Daniel, I. D. Davids, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Atai, W. Domainko, L. O. C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, F. Fiasson, A. Foerster, G. Fontaine, M. Fuessling, S. Gabici, Y. A. Gallant, L. Gerard, B. Giebels, J. F. Glicenstein, B. Glueck, P. Goret, D. Goehring, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, C. Jahn, I. Jung, K. Katarzynski, U. Katz, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khelifi, D. Keogh, W. Kluzniak, N. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Ona Wilhelmi, K. J. Orford, M. Ostrowski, M. Panter, M. Paz Arribas, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Puehlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. RudaK, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schoeck, R. Schroeder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, M. Sikora, J. L. Skilton, H. Sol, D. Spangler, L. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, A. Szostek, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, C. van Eldik, G. Vasileiadis, C. Venter, L. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Voelk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, M. G. Baring, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, A. W. Chen, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, J. Conrad, L. Costamante, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, E. do Couto e Silva, P. S. Drell, R. Dubois, G. Dubus, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, E. C. Ferrara, P. Fleury, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, M.-H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, D. Horan, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, M. Kadler, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knodlseder, F. Kuehn, M. Kuss, J. Lande, L. Latronico, S.-H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, G. M. Madejski, A. Makeev, M. N. Mazziotta, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, A. Y. Rodriguez, F. Ryde, H. F.-W. Sadrozinski, D. Sanchez, A. Sander, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, M. Shaw, D. A. Smith, G. Spandre, P. Spinelli, J.-L. Starck, M. S. Strickman, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, N. Vilchez, M. Villata, V. Vitale, A. P. Waite, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL LETTERS 696 ( 2 ) L150 - L155 2009年05月 [査読有り]

　概要を見る

We report on the first simultaneous observations that cover the optical, X-ray, and high-energy gamma-ray bands of the BL Lac object PKS 2155-304. The gamma-ray bands were observed for 11 days, between 2008 August 25 and 2008 September 6 (MJD 54704-54715), jointly with the Fermi Gamma-ray Space Telescope and the HESS atmospheric Cherenkov array, providing the first simultaneous MeV-TeV spectral energy distribution (SED) with the new generation of gamma-ray telescopes. The ATOM telescope and the RXTE and Swift observatories provided optical and X-ray coverage of the low-energy component over the same time period. The object was close to the lowest archival X-ray and very high energy (VHE; > 100 GeV) state, whereas the optical flux was much higher. The light curves show relatively little (similar to 30%) variability overall when compared to past flaring episodes, but we find a clear optical/VHE correlation and evidence for a correlation of the X-rays with the high-energy spectral index. Contrary to previous observations in the flaring state, we do not find any correlation between the X-ray and VHE components. Although synchrotron self-Compton models are often invoked to explain the SEDs of BL Lac objects, the most common versions of these models are at odds with the correlated variability we find in the various bands for PKS 2155-304.

DOI

Scopus

141

被引用数

(Scopus)
Measurement of the Cosmic Ray e(+)+e(-) Spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, G. Bogaert, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, P. Carlson, J. M. Casandjian, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, G. Di Bernardo, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, C. Farnier, C. Favuzzi, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, D. Gaggero, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, D. Grasso, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, D. Kocevski, F. Kuehn, M. Kuss, J. Lande, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. M. Massai, M. N. Mazziotta, W. McConville, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, M. Pohl, T. A. Porter, S. Profumo, S. Raino, R. Rando, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, T. E. Stephens, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, O. Tibolla, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, A. Van Etten, V. Vasileiou, N. Vilchez, V. Vitale, A. P. Waite, E. Wallace, P. Wang, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

PHYSICAL REVIEW LETTERS 102 ( 18 ) 1101 2009年05月 [査読有り]

　概要を見る

Designed as a high-sensitivity gamma-ray observatory, the Fermi Large Area Telescope is also an electron detector with a large acceptance exceeding 2 m(2) sr at 300 GeV. Building on the gamma-ray analysis, we have developed an efficient electron detection strategy which provides sufficient background rejection for measurement of the steeply falling electron spectrum up to 1 TeV. Our high precision data show that the electron spectrum falls with energy as E-3.0 and does not exhibit prominent spectral features. Interpretations in terms of a conventional diffusive model as well as a potential local extra component are briefly discussed.

DOI

Scopus

934

被引用数

(Scopus)
FERMI/LARGE AREA TELESCOPE DISCOVERY OF GAMMA-RAY EMISSION FROM THE FLAT-SPECTRUM RADIO QUASAR PKS 1454-354

A. A. Abdo, M. Ackermann, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, G. Bogaert, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, J. Conrad, L. Costamante, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, E. do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, C. Farnier, C. Favuzzi, E. C. Ferrara, P. Fleury, W. B. Focke, L. Foschini, M. Frailis, L. Fuhrmann, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, S. E. Healey, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, M. Kadler, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, M. L. Kocian, F. Kuehn, M. Kuss, L. Latronico, S. -H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. Marelli, M. N. Mazziotta, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, E. Nuss, M. Ohno, T. Ohsugi, R. Ojha, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, R. Rando, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, H. F. -W. Sadrozinski, R. Sambruna, D. Sanchez, A. Sander, P. M. Saz Parkinson, C. Sgro, M. S. Shaw, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, D. J. Suson, H. Tajima, H. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, O. Tibolla, D. F. Torres, G. Tosti, A. Tramacere, T. L. Usher, N. Vilchez, V. Vitale, A. P. Waite, P. Wang, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler, P. G. Edwards, M. M. Chester, D. N. Burrows, M. Hauser, S. Wagner

ASTROPHYSICAL JOURNAL 697 ( 1 ) 934 - 941 2009年05月 [査読有り]

　概要を見る

We report the discovery by the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope of high-energy gamma-ray (GeV) emission from the flat-spectrum radio quasar PKS 1454-354 (z = 1.424). On 2008 September 4, the source rose to a peak flux of (3.5 +/- 0.7) x 10(-6) ph cm(-2) s(-1) (E > 100 MeV) on a timescale of hours and then slowly dropped over the following 2 days. No significant spectral changes occurred during the flare. Fermi/LAT observations also showed that PKS 1454-354 is the most probable counterpart of the unidentified EGRET source 3EG J1500-3509. Multiwavelength measurements performed during the following days (7 September with Swift; 6-7 September with the ground-based optical telescope Automated Telescope for Optical Monitoring; 13 September with the Australia Telescope Compact Array) resulted in radio, optical, UV, and X-ray fluxes greater than archival data, confirming the activity of PKS 1454-354.

DOI

Scopus

37

被引用数

(Scopus)
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE VELA PULSAR

A. A. Abdo, M. Ackermann, W. B. Atwood, R. Bagagli, L. Baldini, J. Ballet, D. L. Band, G. Barbiellini, M. G. Baring, J. Bartelt, D. Bastieri, B. M. Baughman, K. Bechtol, F. Bellardi, R. Bellazzini, B. Berenji, D. Bisello, R. D. Blandford, E. D. Bloom, J. R. Bogart, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, F. Camilo, P. A. Caraveo, J. M. Casandjian, M. Ceccanti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, I. Cognard, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, R. Corbet, L. Corucci, S. Cutini, D. S. Davis, M. DeKlotz, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, M. Dormody, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Espinoza, C. Farnier, C. Favuzzi, D. L. Flath, P. Fleury, W. B. Focke, M. Frailis, P. C. C. Friere, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, R. Giannitrapani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, E. V. Gotthelf, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, G. Haller, A. K. Harding, P. A. Hart, R. C. Hartman, E. Hays, G. Hobbs, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, S. Johnston, T. Kamae, G. Kanbach, V. M. Kaspi, H. Katagiri, J. Kataoka, A. Kavelaars, N. Kawai, H. Kelly, M. Kerr, B. Kiziltan, W. Klamra, J. Knodlseder, M. Kramer, F. Kuehn, M. Kuss, J. Lande, D. Landriu, L. Latronico, B. Lee, S. -H. Lee, M. Lemoine-Goumard, M. Livingstone, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, A. G. Lyne, G. M. Madejski, A. Makeev, R. N. Manchester, B. Marangelli, M. Marelli, M. N. Mazziotta, J. E. McEnery, S. McGlynn, M. A. McLaughlin, N. Menon, C. Meurer, P. F. Michelson, T. Mineo, N. Mirizzi, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, M. Mongelli, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, P. L. Nolan, A. Noutsos, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, A. Paccagnella, D. Paneque, J. H. Panetta, D. Parent, M. Pearce, M. Pepe, M. Perchiazzi, M. Pesce-Rollins, L. Pieri, M. Pinchera, F. Piron, T. A. Porter, S. Raino, R. Rando, S. M. Ransom, E. Rapposelli, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, A. Sacchetti, H. F. -W. Sadrozinski, N. Saggini, D. Sanchez, A. Sander, P. M. Saz Parkinson, K. N. Segal, A. Sellerholm, C. Sgro, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, M. Stamatikos, J. -L. Starck, F. W. Stecker, T. E. Stephens, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, A. Tenze, J. B. Thayer, J. G. Thayer, G. Theureau, D. J. Thompson, S. E. Thorsett, L. Tibaldo, O. Tibolla, D. F. Torres, A. Tramacere, M. Turri, T. L. Usher, L. Vigiani, N. Vilchez, V. Vitale, A. P. Waite, P. Wang, K. Watters, P. Weltevrede, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL 696 ( 2 ) 1084 - 1093 2009年05月 [査読有り]

　概要を見る

The Vela pulsar is the brightest persistent source in the GeV sky and thus is the traditional first target for new gamma-ray observatories. We report here on initial Fermi Large Area Telescope observations during verification phase pointed exposure and early sky survey scanning. We have used the Vela signal to verify Fermi timing and angular resolution. The high-quality pulse profile, with some 32,400 pulsed photons at E >= 0.03 GeV, shows new features, including pulse structure as fine as 0.3 ms and a distinct third peak, which shifts in phase with energy. We examine the high-energy behavior of the pulsed emission; initial spectra suggest a phase-averaged power-law index of Gamma = 1.51(-0.04)(+0.05) with an exponential cutoff at E-c = 2.9 +/- 0.1 GeV. Spectral fits with generalized cutoffs of the form e(-(E/Ec)b) require b <= 1, which is inconsistent with magnetic pair attenuation, and thus favor outer-magnetosphere emission models. Finally, we report on upper limits to any unpulsed component, as might be associated with a surrounding pulsar wind nebula.

DOI

Scopus

140

被引用数

(Scopus)
Discovery of Pulsed γ-Rays from the Young Radio Pulsar PSR J1028–5819 with the Fermi Large Area Telescope

Abdo et

The Astrophysical Journal 695 ( 1 ) L72 - L77 2009年04月 [査読有り]

DOI

Scopus

39

被引用数

(Scopus)
A Monte Carlo method for calculating the energy response of plastic scintillators to polarized photons below 100 keV

Mizuno T, Kanai Y, Kataoka J, Kiss M, Kurita K, Pearce M, Tajima H, Takahashi H, Tanaka T, Ueno M, Umeki Y, Yoshida H, Arimoto M, Axelsson M, Bettolo C. Marini, Bogaert G, Chen P, Craig W, Fukazawa Y, Gunji S, Kamae T, Katsuta J, Kawai N, Kishimoto S, Klamra W, Larsson S, Madejski G, Ng J. S. T, Ryde F, Rydstrom S, Takahashi T, Thurston T. S, Varner G

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 600 ( 3 ) 609 - 617 2009年03月 [査読有り]

DOI

Scopus

10

被引用数

(Scopus)
SUZAKU OBSERVATIONS OF THE EXTREME MeV BLAZAR SWIFT J0746.3+2548

Shin Watanabe, Rie Sato, Tadayuki Takahashi, Jun Kataoka, Greg Madejski, Marek Sikora, Fabrizio Tavecchio, Rita Sambruna, Roger Romani, Philip G. Edwards, Tapio Pursimo

ASTROPHYSICAL JOURNAL 694 ( 1 ) 294 - 301 2009年03月 [査読有り]

　概要を見る

We report the Suzaku observations of the high luminosity blazar SWIFT J0746.3+2548 (J0746) conducted in 2005 November. This object, which, with z = 2.979, is the highest redshift source observed in the Suzaku Guaranteed Time Observer period, is likely to show high gamma-ray flux peaking in the MeV range. As a result of the good photon statistics and high signal-to-noise ratio spectrum, the Suzaku observation clearly confirms that J0746 has an extremely hard spectrum in the energy range of 0.3-24 keV, which is well represented by a single power-law with a photon index of Gamma(ph) similar or equal to 1.17 and Galactic absorption. The multiwavelength spectral energy distribution of J0746 shows two continuum components, and is well modeled assuming that the high-energy spectral component results from Comptonization of the broad-line region photons. In this paper, we search for the bulk Compton spectral features predicted to be produced in the soft X-ray band by scattering external optical/UV photons by cold electrons in a relativistic jet. We discuss and provide constraints on the pair content resulting from the apparent absence of such features.

DOI

Scopus

8

被引用数

(Scopus)
Fermi Observations of High-Energy Gamma-Ray Emission from GRB 080916C

A. A. Abdo, M. Ackermann, M. Arimoto, K. Asano, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, D. L. Band, G. Barbiellini, M. G. Baring, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, F. Bellardi, R. Bellazzini, B. Berenji, P. N. Bhat, E. Bissaldi, R. D. Blandford, E. D. Bloom, G. Bogaert, J. R. Bogart, E. Bonamente, J. Bonnell, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. S. Briggs, M. Brigida, P. Bruel, T. H. Burnett, D. Burrows, G. Busetto, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, M. Ceccanti, C. Cecchi, A. Celotti, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, V. Connaughton, J. Conrad, L. Costamante, S. Cutini, M. DeKlotz, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, B. L. Dingus, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, P. A. Evans, D. Fabiani, C. Farnier, C. Favuzzi, J. Finke, G. Fishman, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, T. Glanzman, G. Godfrey, A. Goldstein, J. Granot, J. Greiner, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, G. Haller, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, J. A. Hernando Morata, A. Hoover, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, A. Kavelaars, N. Kawai, H. Kelly, J. Kennea, M. Kerr, R. M. Kippen, J. Knoedlseder, D. Kocevski, M. L. Kocian, N. Komin, C. Kouveliotou, F. Kuehn, M. Kuss, J. Lande, D. Landriu, S. Larsson, L. Latronico, C. Lavalley, B. Lee, S. -H. Lee, M. Lemoine-Goumard, G. G. Lichti, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, B. Marangelli, M. N. Mazziotta, S. McBreen, J. E. McEnery, S. McGlynn, C. Meegan, P. Meszaros, C. Meurer, P. F. Michelson, M. Minuti, N. Mirizzi, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, D. Nelson, P. L. Nolan, J. P. Norris, E. Nuss, M. Ohno, T. Ohsugi, A. Okumura, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, W. S. Paciesas, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Perri, M. Pesce-Rollins, V. Petrosian, M. Pinchera, F. Piron, T. A. Porter, R. Preece, S. Raino, E. Ramirez-Ruiz, R. Rando, E. Rapposelli, M. Razzano, S. Razzaque, N. Rea, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, M. Roth, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, K. N. Segal, C. Sgro, T. Shimokawabe, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, M. Stamatikos, J. -L. Starck, F. W. Stecker, H. Steinle, T. E. Stephens, M. S. Strickman, D. J. Suson, G. Tagliaferri, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, A. Tenze, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, M. Turri, S. Tuvi, T. L. Usher, A. J. van der Horst, L. Vigiani, N. Vilchez, V. Vitale, A. von Kienlin, A. P. Waite, D. A. Williams, C. Wilson-Hodge, B. L. Winer, K. S. Wood, X. F. Wu, R. Yamazaki, T. Ylinen, M. Ziegler

SCIENCE 323 ( 5922 ) 1688 - 1693 2009年03月 [査読有り]

　概要を見る

Gamma-ray bursts (GRBs) are highly energetic explosions signaling the death of massive stars in distant galaxies. The Gamma-ray Burst Monitor and Large Area Telescope onboard the Fermi Observatory together record GRBs over a broad energy range spanning about 7 decades of gamma-ray energy. In September 2008, Fermi observed the exceptionally luminous GRB 080916C, with the largest apparent energy release yet measured. The high-energy gamma rays are observed to start later and persist longer than the lower energy photons. A simple spectral form fits the entire GRB spectrum, providing strong constraints on emission models. The known distance of the burst enables placing lower limits on the bulk Lorentz factor of the outflow and on the quantum gravity mass.

DOI

Scopus

616

被引用数

(Scopus)
Modelling the broad-band spectra of X-ray emitting GPS galaxies

L. Ostorero, R. Moderski, Stawarz, M. C. Begelman, A. Diaferio, I. Kowalska, J. Kataoka, S. J. Wagner

Astronomische Nachrichten 330 ( 2-3 ) 275 - 278 2009年02月

　概要を見る

The study of the broad-band emission of GHz-Peaked-Spectrum (GPS) radio galaxies is a powerful tool to investigate the physical processes taking place in the central, kpc-sized region of their active hosts, where the jets propagate and the lobes expand, interacting with the surrounding interstellar medium (ISM). We recently developed a new dynamical-radiative model to describe the evolution of the GPS phenomenon (Stawarz et al. 2008): as the relativistic jets propagate through the ISM, gradually engulfing narrow-line emitting gas clouds along their way, the electron population of the expanding lobes evolves, emitting synchrotron light, as well as inverse-Compton radiation via up-scattering of the photon fields from the host galaxy and its active nucleus. The model, which successfully reproduces the key features of the GPS radio sources as a class, provides a description of the evolution of their spectral energy distribution (SED) with the lobes' expansion, predicting significant and complex X-ray to γ-ray emission. We apply here the model to the broad-band SED's of a sample of known, X-ray emitting GPS galaxies, and show that (i) the free-free absorption mechanism enables us to reproduce the radio continuum at frequencies below the turnover; (ii) the lobes' non-thermal, inverse-Compton emission can account for the observed X-ray spectra, providing a viable alternative to the thermal, accretion-dominated scenario. We also show that, in our sample, the relationship between the X-ray and radio hydrogen column densities, NH and NHI, is suggestive of a positive correlation, which, if confirmed, would support the scenario of high-energy emitting lobes. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA.

DOI

Scopus

5

被引用数

(Scopus)
On-board and Ground Data Processing System of MAXI

ISHIKAWA Masaki, TAKAHASHI Daiki, MATSUOKA Masaru, UENO Shiro, TOMIDA Hiroshi, KATAYAMA Haruyoshi, KAWASAKI Kazuyoshi, KOHAMA Mitsuhiro, SUZUKI Motoko, ADACHI Yasuki, MIHARA Tatehiro, ISOBE Naoki, TSUNEMI Hiroshi, MIYATA Emi, YOSHIDA Atsumasa, YAMAOKA Kazutaka, KAWAI Nobuyuki, KATAOKA Jun, NAKAJIMA Motoki, NEGORO Hiroshi, MORII Mikio

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, SPACE TECHNOLOGY JAPAN 7 ( ists26 ) Tf_43 - Tf_48 2009年

　概要を見る

MAXI (Monitor of All sky X-ray Image) is the first X-ray observation payload to be installed to EF (Exposed Facility) of Kibo (JEM: Japanese Experiment Module) on ISS (International Space Station). One of the important missions of MAXI is to quickly release novae or transient information of X-ray sources through its alert system to the worldwide astronomers. For this purpose, MAXI is equipped with a unique data transfer system both for the ground and on-board handling, which fully utilizes the communication system of ISS. The uniqueness of the data transfer system of MAXI comes from the fact that it is a payload of ISS, and is not seen in the ordinary payloads on free flyers (satellites). MAXI analyzes the observation data automatically in real time, and an alert for the novae or transient sources can be distributed widely through internet based on the analysis result. Various restrictions are imposed to keep tight security even on the ground system of ISS payloads. This paper describes the data transmission process in each stage, namely that in MAXI, the ISS communication links between the ISS and ground, and the process in the MAXI ground system.

DOI CiNii
Versatile APD-based PET Modules for High Resolution, Fast Medical Imaging

J. Kataoka, H. Matsuda, M. Yoshino, T. Miura, F. Nishikido, M. Koizumi, T. Tanaka, H. Ikeda, Y. Ishikawa, N. Kawabata, Y. Matsunaga, S. Kishimoto, H. Kubo

2009 IEEE NUCLEAR SCIENCE SYMPOSIUM CONFERENCE RECORD, VOLS 1-5 3542 - + 2009年 [査読有り]

　概要を見る

We report on the development of versatile APD-based PET modules with time-of-flight capability. The module consists of a LYSO matrix optically coupled with a position-sensitive avalanche photodiode (APD) array, and front-end circuits (FEC) directly connected to the rear-end of the APD package. Each APD device has a monolithic 16x16 (or 8x8) pixel structure with an active area of 1.0 (or 4.0) mm(2) for each pixel. Time resolutions of 155 ps and 214 ps (FWHM) were obtained for 1.0 mm(2) and 4.0 mm(2) APD pixels, respectively, measured by the direct detection of 10 keV X-rays. The FEC carries two identical analog ASICs specifically designed for the APDs in TSMC 0.35 mu m CMOS technology. Each ASIC consists of 32-channel charge-sensitive amplifiers, band-pass filters, differentiators, pulse-height and timing discriminators, and two-channel time-to-amplitude converters. The noise characteristic of the ASIC, mounted in a low temperature co-fired ceramics (LTCC) package, is 560 +30 e(-)/pF with an electric timing resolution of 484 ps (rms). The overall dimension of the module (including APD-array, LYSO matrix and FEC) is 30x30x80 mm(3). The variation of signal amplitude was less than 20% among all pixels. The average energy resolutions of 11.7 +/- 0.7 % and 13.7 +/- 1.1 % were obtained for 662 key gamma-rays, measured with 8x8 and 16x16 arrays, respectively. An attainable spatial resolution is < 0.8mm (FWHM) for 16x16 array in a reconstructed image. These results suggest the APD-based PET module can be a promising device for future applications, especially for high resolution MRI- and TOF-PET.
The Soft Gamma-Ray Detector for the ASTRO-H Mission

T. Tanaka, R. Blandford, K. Doutsu, T. Endo, T. Enoto, Y. Fukazawa, K. Fukami, T. Fukuyama, Y. Hanabata, J. Harayama, K. Hayashi, K. Hiragi, S. Ishikawa, J. Kataoka, J. Katsuta, T. Kitaguchi, M. Kokubun, M. Koseki, T. Kozu, G. Madejski, K. Makishima, M. Matsuoka, T. Miura, T. Mizuno, S. Nakahira, K. Nakajima, K. Nakazawa, S. Nishino, H. Nishioka, H. Noda, H. Odaka, S. Saito, S. Sasaki, R. Sato, S. Sugimoto, H. Tajima, T. Takahashi, M. Tashiro, Y. Terada, S. Torii, Y. Uchiyama, Y. Umeki, S. Watanabe, Y. Yaji, S. Yamada, K. Yamaoka, M. Yoshino, T. Yuasa

2009 IEEE NUCLEAR SCIENCE SYMPOSIUM CONFERENCE RECORD, VOLS 1-5 2140 - 2144 2009年 [査読有り]

　概要を見る

The Soft Gamma-ray Detector (SGD) on board ASTRO-H (Japanese next high-energy astrophysics mission) is a Compton telescope with narrow field-of-view, which utilizes Compton kinematics to enhance its background rejection capabilities. It is realized as a hybrid semiconductor detector system which consists of silicon and CdTe (cadmium telluride) detectors. It can detect photons in a wide energy band (50-600 keV) at a background level 10 times better than that of the Suzaku Hard X-ray Detector, and is complimentary to the Hard X-ray Imager on board ASTRO-H with an energy coverage of 5-80 keV. Excellent energy resolution is the key feature of the SGD, allowing it to achieve good background rejection capability taking advantage of good angular resolution. An additional capability of the SGD, its ability to measure gamma-ray polarization, opens up a new window to study properties of gamma-ray emission processes. Here we describe the instrument design of the SGD, its expected performance, and its development status.
Beam, Test Results of the Polarized Gamma-Ray Observer, PoGOLite

H. Takahashi, M. Matsuoka, Y. Umeki, H. Yoshida, T. Tanaka, T. Mizuno, Y. Fukazawa, T. Kamae, G. Madejski, H. Tajima, M. Kiss, W. Klamra, S. Larsson, C. Marini Bettolo, M. Pearce, F. Ryde, S. Rydstrom, K. Kurita, Y. Kanai, M. Arimoto, A. Ueno, J. Kataoka, N. Kawai, M. Axelsson, L. Hjalmarsdotter, G. Bogaert, S. Gunji, T. Takahashi, G. Varner, T. Yuasa

2008 IEEE NUCLEAR SCIENCE SYMPOSIUM AND MEDICAL IMAGING CONFERENCE (2008 NSS/MIC), VOLS 1-9 13 - + 2009年 [査読有り]

　概要を見る

The Polarized Gamma-ray Observer, PoGOLite, is a balloon experiment with the capability of detecting 10% polarization from a 200 mCrab celestial object in the energy range 25-80 keV. During a beam test at KEK-PF in February 2008, 20 detector units were assembled, and a 50 keV X-ray beam with a polarization degree of similar to 90% was irradiated at the center unit. Signals from all 20 units were fed into flight-version electronics consisting of six circuit boards (four waveform digitizer boards, one digital I/O board and one router board) and one microprocessor (SpaceCube), which communicate using a SpaceWire interface. One digitizer board, which can associate up to 8 PDCs, outputs a trigger signal. The digital I/O board handles the trigger and returns a data acquisition request if there is no veto signal (upper or pulse-shape discriminators) from any detector unit. This data acquisition system worked well, and the modulation factor was successfully measured to be similar to 34%. These results confirmed the capabilities of both detector and data-acquisition system for a pathfinder flight planned in 2010.
TSUBAME: toward the Frontier of X-ray/Gamma-ray Polarimetry in Astronomy

TOIZUMI Takahiro, KATAOKA Jun, TSUBUKU Yoshihiro, KOBAYASHI Mitsuyoshi, YATSU Yoichi, ARIMOTO Makoto, SHIMOKAWABE Takashi, KAWAI Nobuyuki, OMAGARI Kuniyuki, FUJIWARA Ken, ASHIDA Hiroki, NISHIDA Junichi, FUJIHASHI Kota, INAGAWA Shinich, MIURA Yoshiyuki, MATSUNAGA Saburo

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, SPACE TECHNOLOGY JAPAN 7 ( 26 ) Tm_31 - Tm_35 2009年

　概要を見る

"TSUBAME" is a university-built small satellite mission to measure polarization of hard X-ray photons (30-200 keV) from gamma-ray bursts (GRBs) using azimuthal anisotropy of Compton-scattered photons. Polarimetry in the hard X-ray and soft γ-ray bands should provide crucial information for understanding the high-energy emission mechanisms and the distribution of magnetic fields and radiation fields in the astrophysical sources. TSUBAME has two instruments: the Wide-field Burst Monitor (WBM) and the Hard X-ray Compton Polarimeter (HXCP). The WBM determines on board the direction of the burst occurrence with an accuracy of 10 degrees, then using a high speed attitude control device, the HXCP is pointed to the GRB within 15 seconds after the burst occurrence to promptly detect polarized X-ray photons from the GRB. We present an overview of the TSUBAME mission, its estimated scientific capability for detecting GRBs and measuring their X-ray polarization, development of multi-anode photomultiplier tubes that use ultra bi-alkali photocathodes, and the future plans of this mission.

DOI CiNii
Discovery of pulsations from the pulsar J0205+6449 in SNR 3C 58 with the fermi gamma-ray space telescope

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, F. Camilo, P. A. Caraveo, J. M. Casandjian, C. Cecchi, Ö Çelik, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, I. Cognard, J. Cohen-Tanugi, J. Conrad, C. D. Dermer, A. De Angelis, F. De Palma, S. W. Digel, M. Dormody, E. Do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, C. Espinoza, C. Farnier, C. Favuzzi, W. B. Focke, M. Frailis, P. C.C. Freire, Y. Fukazawa, P. Fusco, F. Gargano, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, G. Hobbs, R. E. Hughes, G. Jóhannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, S. Johnston, T. Kamae, V. M. Kaspi, H. Katagiri, J. Kataoka, N. Kawai, M. Keith, M. Kerr, J. Knödlseder, M. Kramer, F. Kuehn, M. Kuss, J. Lande, L. Latronico, M. Lemoine-Goumard, M. Livingstone, F. Longo, F. Loparco, B. Lott, M. N. Lovellette

Astrophysical Journal 699 ( 2 PART 2 ) 2009年

　概要を見る

We report the discovery of γ-ray pulsations (≥0.1 GeV) from the young radio and X-ray pulsar PSR J0205 + 6449 located in the Galactic supernova remnant 3C 58. Data in the γ-ray band were acquired by the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope (formerly GLAST), while the radio rotational ephemeris used to fold γ-rays was obtained using both the Green Bank Telescope and the Lovell telescope at Jodrell Bank. The light curve consists of two peaks separated by 0.49 ± 0.01 ± 0.01 cycles which are aligned with the X-ray peaks. The first γ-ray peak trails the radio pulse by 0.08 ± 0.01 ± 0.01, while its amplitude decreases with increasing energy as for the other γ-ray pulsars. Spectral analysis of the pulsed γ-ray emission suggests a simple power law of index -2.1 ± 0.1 ± 0.2 with an exponential cutoff at 3.0+1.1-0.7 ± 0.4 GeV. The first uncertainty is statistical and the second is systematic. The integral γ-ray photon flux above 0.1 GeV is (13.7 ± 1.4 ± 3.0) × 10-8cm-2s -1, which implies for a distance of 3.2kpc and assuming a broad fan-like beam a luminosity of 8.3 × 1034ergs-1 and an efficiency η of 0.3%. Finally, we report a 95% upper limit on the flux of 1.7 × 10-8cm-2s-1 for off-pulse emission from the object. © 2009. The American Astronomical Society. All rights reserved.

DOI

Scopus

34

被引用数

(Scopus)
Simultaneous multiwavelength observation of mkn 501 in a low state in 2006

H. Anderhub, L. A. Antonelli, P. Antoranz, M. Backes, C. Baixeras, S. Balestra, J. A. Barrio, D. Bastieri, J. Becerra Gonzlez, J. K. Becker, W. Bednarek, K. Berger, E. Bernardini, A. Biland, R. K. Bock, G. Bonnoli, P. Bordas, D. Borla Tridon, V. Bosch-Ramon, D. Bose, I. Braun, T. Bretz, I. Britvitch, M. Camara, E. Carmona, S. Commichau, J. L. Contreras, J. Cortina, M. T. Costado, S. Covino, V. Curtef, F. Dazzi, A. De Angelis, E. De Cea Del Pozo, R. De Los Reyes, B. De Lotto, M. De Maria, F. De Sabata, C. Delgado Mendez, A. Dominguez, D. Dorner, M. Doro, D. Elsaesser, M. Errando, D. Ferenc, E. Fernndez, R. Firpo, M. V. Fonseca, L. Font, N. Galante, R. J.García López, M. Garczarczyk, M. Gaug, F. Goebel, D. Hadasch, M. Hayashida, A. Herrero, D. Hildebrand, D. Höhne-Mönch, J. Hose, C. C. Hsu, T. Jogler, D. Kranich, A. La Barbera, A. Laille, E. Leonardo, E. Lindfors, S. Lombardi, F. Longo, M. López, E. Lorenz, P. Majumdar, G. Maneva, N. Mankuzhiyil, K. Mannheim, L. Maraschi, M. Mariotti, M. Martínez, D. Mazin, M. Meucci, M. Meyer, J. M. Miranda, R. Mirzoyan, H. Miyamoto, J. Moldón, M. Moles, A. Moralejo, D. Nieto, K. Nilsson, J. Ninkovic, N. Otte, I. Oya, R. Paoletti, J. M. Paredes, M. Pasanen, D. Pascoli, F. Pauss, R. G. Pegna, M. A. Perez-Torres, M. Persic

Astrophysical Journal 705 ( 2 ) 1624 - 1631 2009年

　概要を見る

We present results of the multiwavelength campaign on the TeV blazar Mkn 501 performed in 2006 July, including MAGIC for the very-high-energy (VHE) γ-ray band and Suzaku for the X-ray band. A VHE γ-ray signal was clearly detected with an average flux above 200 GeV of 20% of the Crab Nebula flux, which indicates a low state of source activity in this energy range. No significant variability has been found during the campaign. The VHE γ-ray spectrum can be described by a simple power law from 80 GeV to 2 TeV with a photon index of 2.8 0.1, which corresponds to one of the steepest photon indices observed in this energy range so far for this object. The X-ray spectrum covers a wide range from 0.6 to 40 keV, and is well described by a broken power law, with photon indices of 2.257 0.004 and 2.420 0.012 below and above the break energy of 3.24+0.13-0.12 keV. No apparent high-energy cut-off is seen above the break energy. Although an increase of the flux of about 50% is observed in the X-ray band within the observation, the data indicate a consistently low state of activity for this source. Time-resolved spectra show an evidence for spectral hardening with a flux level. A homogeneous one-zone synchrotron self-Compton (SSC) model can adequately describe the spectral energy distribution (SED) from the X-ray to the VHE γ-ray bands with a magnetic field intensity B = 0.313 G and a Doppler beaming factor δ = 20, which are similar to the values in the past multiwavelength campaigns in high states. Based on our SSC parameters derived for the low state, we are able to reproduce the SED of the high state by just changing the Lorentz factor of the electrons corresponding to the break energy in the primary electron spectrum. This suggests that the variation of the injected electron population in the jet is responsible for the observed low-high state variation of the SED. © 2009 The American Astronomical Society. All rights reserved.

DOI

Scopus

48

被引用数

(Scopus)
The MAXI mission on the ISS: Science and instruments for monitoring All-sky X-ray Images

Masaru Matsuoka, Kazuyoshi Kawasaki, Shiro Ueno, Hiroshi Tomida, Mitsuhiro Kohama, Motoko Suzuki, Yasuki Adachi, Masaki Ishikawa, Tatehiro Mihara, Mutsumi Sugizaki, Naoki Isobe, Yujin Nakagawa, Hiroshi Tsunemi, Emi Miyata, Nobuyuki Kawai, Jun Kataoka, Mikio Morii, Atsumasa Yoshida, Hitoshi Negoro, Motoki Nakajima, Yoshihiro Ueda, Hirotaka Chujo, Kazutaka Yamaoka, Osamu Yamazaki, Satoshi Nakahira, Tetsuya You, Ryoji Ishiwata, Sho Miyoshi, Satoshi Eguchi, Kazuo Hiroi, Haruyoshi Katayama, Ken Ebisawa

Publications of the Astronomical Society of Japan 61 ( 5 ) 999 - 1010 2009年

　概要を見る

The Monitor of All-sky X-ray Image (MAXI) mission is the first astronomical payload to be installed on the Japanese Experiment Module - Exposed Facility (JEM-EF or Kibo-EF) on the International Space Station. It has two types of X-ray slit cameras with wide FOVs and two kinds of X-ray detectors consisting of gas proportional counters covering the energy range of 2 to 30 keV and X-ray CCDs covering the energy range of 0.5 to 12 keV. MAXI will be more powerful than any previous X-ray All Sky Monitor payloads, being able to monitor hundreds of Active Galactic Nuclei. A realistic simulation under optimal observation conditions suggests that MAXI will provide all-sky images of X-ray sources of ∼20 mCrab (∼7 × 10-10ergcm-2s-1 in the energy band of 2-30 keV) from observations during one ISS orbit (90 min), ∼4.5 mCrab for one day, and ∼2 mCrab for one week. The final detectability of MAXI could be ∼0.2 mCrab for two years, which is comparable to the source confusion limit of the MAXI field of view (FOV). The MAXI objectives are: (1) to alert the community to X-ray novae and transient X-ray sources, (2) to monitor long-term variabilities of X-ray sources, (3) to stimulate multi-wavelength observations of variable objects, (4) to create unbiased X-ray source cataloges, and (5) to observe diffuse cosmic X-ray emissions, especially with better energy resolution for soft X-rays down to 0.5 keV. © 2009. Astronomical Society of Japan.

DOI

Scopus

680

被引用数

(Scopus)
Multiwavelength observations of 3C 454.3. II. the agile 2007 december campaign

I. Donnarumma, G. Pucella, V. Vittorini, F. D'Ammando, S. Vercellone, C. M. Raiteri, M. Villata, M. Perri, W. P. Chen, R. L. Smart, J. Kataoka, N. Kawai, Y. Mori, G. Tosti, D. Impiombato, T. Takahashi, R. Sato, M. Tavani, A. Bulgarelli, A. W. Chen, A. Giuliani, F. Longo, L. Pacciani, A. Argan, G. Barbiellini, F. Boffelli, P. Caraveo, P. W. Cattaneo, V. Cocco, T. Contessi, E. Costa, E. Del Monte, G. De Paris, G. Di Cocco, Y. Evangelista, M. Feroci, A. Ferrari, M. Fiorini, T. Froysland, M. Frutti, F. Fuschino, M. Galli, F. Gianotti, C. Labanti, I. Lapshov, F. Lazzarotto, P. Lipari, M. Marisaldi, M. Mastropietro, S. Mereghetti, E. Morelli, E. Moretti, A. Morselli, A. Pellizzoni, F. Perotti, G. Piano, P. Picozza, M. Pilia, G. Porrovecchio, M. Prest, M. Rapisarda, A. Rappoldi, A. Rubini, S. Sabatini, E. Scalise, P. Soffitta, E. Striani, M. Trifoglio, A. Trois, E. Vallazza, A. Zambra, D. Zanello, C. Pittori, P. Santolamazza, F. Verrecchia, P. Giommi, L. A. Antonelli, S. Colafrancesco, L. Salotti

Astrophysical Journal 707 ( 2 ) 1115 - 1123 2009年

　概要を見る

We report on the second Astrorivelatore Gamma a Immagini Leggero (AGILE) multiwavelength campaign of the blazar 3C 454.3 during the first half of 2007 December. This campaign involved AGILE, Spitzer, Swift, Suzaku, the Whole Earth Blazar Telescope (WEBT) consortium, the Rapid Eye Mount (REM), and the Multicolor Imaging Telescopes for Survey and Monstrous Explosions (MITSuME) telescopes, offering a broadband coverage that allowed for a simultaneous sampling of the synchrotron and inverse Compton (IC) emissions. The two-week AGILE monitoring was accompanied by radio to optical monitoring by WEBT and REM, and by sparse observations in mid-infrared and soft/hard X-ray energy bands performed by means of Target of Opportunity observations by Spitzer, Swift, and Suzaku, respectively. The source was detected with an average flux of ∼250 × 10-8photonscm-2s-1 above 100 MeV, typical of its flaring states. The simultaneous optical and γ-ray monitoring allowed us to study the time lag associated with the variability in the two energy bands, resulting in a possible ≲one-day delay of the γ-ray emission with respect to the optical one. From the simultaneous optical and γ-ray fast flare detected on December 12, we can constrain the delay between the γ-ray and optical emissions within 12 hr. Moreover, we obtain three spectral energy distributions (SEDs) with simultaneous data for 2007 December 5, 13, and 15, characterized by the widest multifrequency coverage. We found that a model with an external Compton on seed photons by a standard disk and reprocessed by the broad-line regions does not describe in a satisfactory way the SEDs of 2007 December 5, 13, and 15. An additional contribution, possibly from the hot corona with T = 106 K surrounding the jet, is required to account simultaneously for the softness of the synchrotron and the hardness of the IC emissions during those epochs. © 2009. The American Astronomical Society. All rights reserved.

DOI

Scopus

41

被引用数

(Scopus)
VERITAS upper limit on the very high energy emission from the radio galaxy NGC 1275

V. A. Acciari, E. Aliu, T. Arlen, T. Aune, M. Bautista, M. Beilicke, W. Benbow, D. Boltuch, S. M. Bradbury, J. H. Buckley, V. Bugaev, K. Byrum, A. Cannon, O. Celik, A. Cesarini, L. Ciupik, P. Cogan, W. Cui, R. Dickherber, C. Duke, S. J. Fegan, J. P. Finley, P. Fortin, L. Fortson, A. Furniss, N. Galante, D. Gall, K. Gibbs, G. H. Gillanders, S. Godambe, J. Grube, R. Guenette, G. Gyuk, D. Hanna, J. Holder, D. Horan, C. M. Hui, T. B. Humensky, A. Imran, P. Kaaret, N. Karlsson, M. Kertzman, D. Kieda, A. Konopelko, H. Krawczynski, F. Krennrich, M. J. Lang, S. Lebohec, G. Maier, A. McCann, M. McCutcheon, J. Millis, P. Moriarty, R. Mukherjee, R. A. Ong, A. N. Otte, D. Pandel, J. S. Perkins, M. Pohl, J. Quinn, K. Ragan, P. T. Reynolds, E. Roache, H. J. Rose, M. Schroedter, G. H. Sembroski, A. W. Smith, D. Steele, S. P. Swordy, M. Theiling, J. A. Toner, A. Varlotta, V. V. Vassiliev, S. Vincent, R. G. Wagner, S. P. Wakely, J. E. Ward, T. C. Weekes, A. Weinstein, T. Weisgarber, D. A. Williams, S. Wissel, M. Wood, B. Zitzer, J. Kataoka, E. Cavazzuti, C. C. Cheung, B. Lott, D. J. Thompson, G. Tosti

Astrophysical Journal 706 ( 2 PART 2 ) 2009年

　概要を見る

The recent detection by the Fermi γ-ray space telescope of high-energy γ-rays from the radio galaxy NGC1275 makes the observation of the very high energy (VHE: E>100GeV) part of its broadband spectrum particularly interesting, especially for the understanding of active galactic nuclei with misaligned multi-structured jets. The radio galaxy NGC 1275 was recently observed by VERITAS at energies above 100GeV for about 8hr. No VHE γ-ray emission was detected by VERITAS from NGC 1275. A 99% confidence level upper limit of 2.1% of the Crab Nebula flux level is obtained at the decorrelation energy of approximately 340GeV, corresponding to 19% of the power-law extrapolation of the Fermi Large Area Telescope result. © 2009. The American Astronomical Society. All rights reserved.

DOI

Scopus

27

被引用数

(Scopus)
Radio-loud narrow-line Seyfert 1 as a new class of gamma-ray active galactic nuclei

A. A. Abdo, M. Ackermann, M. Ajello, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, C. Cecchi, Ö Çelik, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, J. Conrad, S. Cutini, C. D. Dermer, F. De Palma, E. Do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, W. B. Focke, L. Foschini, M. Frailis, Y. Fukazawa, P. Fusco, F. Gargano, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, J. E. Grove, L. Guillemot, S. Guiriec, M. Hayashida, E. Hays, D. Horan, R. E. Hughes, G. Jóhannesson, A. S. Johnson, W. N. Johnson, M. Kadler, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, A. Makeev, M. N. Mazziotta, W. McConville, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes

Astrophysical Journal 707 ( 2 PART 2 ) 2009年

　概要を見る

We report the discovery with Fermi/LAT of γ-ray emission from three radio-loud narrow-line Seyfert 1 galaxies: PKS 1502+036 (z = 0.409), 1H 0323+342 (z = 0.061), and PKS 2004 - 447 (z = 0.24). In addition to PMN J0948+0022 (z = 0.585), the first source of this type to be detected in γ rays, they may form an emerging new class of γ-ray active galactic nuclei (AGNs). These findings can have strong implications on our knowledge about relativistic jets and the unified model of the AGN. © 2009. The American Astronomical Society.

DOI

Scopus

267

被引用数

(Scopus)
Fermi/lat observations of LS 5039

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, S. Buson, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, Ö Çelik, S. Chaty, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, S. Corbel, R. Corbet, S. Cutini, C. D. Dermer, A. De Angelis, F. De Palma, S. W. Digel, E. Docouto E Silva, P. S. Drell, R. Dubois, G. Dubus, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, W. B. Focke, P. Fortin, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, A. B. Hill, D. Horan, R. E. Hughes, M. S. Jackson, G. Jóhannesson, A. S. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knödlseder, M. L. Kocian, F. Kuehn, M. Kuss, J. Lande, S. Larsson, L. Latronico, M. Lemoine-Goumard, F. Longo

Astrophysical Journal 706 ( 1 PART 2 ) 2009年

　概要を見る

The first results from observations of the high-mass X-ray binary LS 5039 using the Fermi Gamma-ray Space Telescope data between 2008 August and 2009 June are presented. Our results indicate variability that is consistent with the binary period, with the emission being modulated with a period of 3.903 ± 0.005 days; the first detection of this modulation at GeV energies. The light curve is characterized by a broad peak around superior conjunction in agreement with inverse Compton scattering models. The spectrum is represented by a power law with an exponential cutoff, yielding an overall flux (100 MeV-300 GeV) of 4.9 ± 0.5(stat) 1.8(syst) ×10-7 photon cm-2 s-1, with a cutoff at 2.1 ± 0.3(stat) 1.1(syst) GeV and photon index Γ = 1.9 ± 0.1(stat) 0.3(syst). The spectrum is observed to vary with orbital phase, specifically between inferior and superior conjunction. We suggest that the presence of a cutoff in the spectrum may be indicative of magnetospheric emission similar to the emission seen in many pulsars by Fermi. © 2009. The American Astronomical Society. All rights reserved.

DOI

Scopus

142

被引用数

(Scopus)
Can the extragalactic gamma-ray background be explained by AGN?

Tanja M. Kneiske, Karl Mannheim, Lukasz Stawarz, Jun Kataoka

AIP Conference Proceedings 1085 510 - 513 2009年

　概要を見る

Very high energy gamma-rays from blazars traversing cosmological distances through the meta-galactic radiation field can convert into electron-positron pairs in photon-photon collisions. The converted gamma-rays initiate electromagnetic cascades driven by inverse-Compton scattering with microwave background photons. Using a model for the time-dependent meta-galactic radiation field consistent with currently available far-infrared to optical data, the cascade contributions by faint, unresolved sources like blazars and FRI galaxies have been calculated. We come to the conclusion that depending on what is known so far about AGN, they are not able to produce the total extragalactic flux detected by EGRET. A test for the model will be the upcoming observations with FERMI. It would also be helpful to detect a signal above 100 GeV where the gamma-ray flux declines to 10-7GeV sr-1 cm-2 s-1. © 2009 American Institute of Physics.

DOI

Scopus
Chandra reveals twin X-ray jets in the powerful FR II radio galaxy 3C 353

Jun Kataoka

AIP Conference Proceedings 1085 435 - 438 2009年

　概要を見る

We report X-ray imaging of the powerful FR II radio galaxy 3C 353 using the Chandra X-ray Observatory. 3C 353's two 4"-wide and 2'-long jets allow us to study in detail the internal structure of the large-scale relativistic outflows at both radio and X-ray photon energies with the sub-arcsecond spatial resolution provided by the VLA and Chandra instruments. In a 90 ks Chandra observation, we have detected X-ray emission from most radio structures in 3C 353, including the nucleus, the jet and the counterjet, the terminal jet regions (hotspots), and one radio lobe. We show that the detection of the X-ray emission associated with the radio knots and counterknots, which is most likely non-thermal in origin, puts several crucial constraints on the X-ray emission mechanisms in powerful large-scale jets of quasars and FR II sources. In particular, we show that this detection is inconsistent with the inverse-Compton model proposed in the literature, and instead implies a synchrotron origin of the X-ray jet photons. We also find that the width of the X-ray counterjet is possibly narrower than that measured in radio bands, that the radio-to-X-ray flux ratio decreases systematically downstream along the jets, and that there are substantial (kpc-scale) offsets between the positions of the X-ray and radio intensity maxima within each knot, whose magnitudes increase away from the nucleus. We discuss all these findings in the wider context of the physics of extragalactic jets, proposing some particular though not definitive solutions or interpretations for each problem. In general, we find that the synchrotron X-ray emission of extragalactic large-scale jets is not only shaped by the global hydrodynamical configuration of the outflows, but is also likely to be very sensitive to the microscopic parameters of the jet plasma. A complete, self-consistent model for the X-ray emission of extragalactic jets still remains elusive. © 2009 American Institute of Physics.

DOI

Scopus
Status and expected perfomance of the MAXI mission for the JEM/ISS

J. Kataoka, N. Kawai

AIP Conference Proceedings 1085 830 - 833 2009年

　概要を見る

MAXI (Monitor of All-sky X-ray Image) is the first payload to be attached on JEM-EF (Kibo exposed facility) of ISS. It provides an all sky X-ray image every ISS orbit. Only with a few weeks scan, MAXI is expected to make a milli-Crab X-ray all sky map excluding bright region around the sun. Thus, MAXI does not only inform X-ray novae and transients rapidly to world astronomers if once they occur, but also observes long-term variability of Galact ic and extra-Galactic X-ray sources. MAXI also provides an X-ray source catalogue at that time with diffuse cosmic X-ray background. MAXI consists of two kinds of detectors, position sensitive gas-proportional counters for 2-30 keV X-rays and CCD cameras for 0.5-10 keV X-rays. All instruments of MAXI are now in final phase of pre-launching tests of their flight modules. We are also carrying out performance tests for X-ray detectors and collimators. Data processing and analysis software including alert system on ground are being developed by mission team. In this paper we report an overview of final instruments of MAXI and capability of MAXI. © 2009 American Institute of Physics.

DOI

Scopus
Development of wide-band X-ray/gamma-ray imagers using reach through APD arrays

T. Nakamori, J. Kataoka, T. Toizumi, M. Koizumi, S. Tanaka, Y. Kanai, Y. Yatsu, N. Kawai, Y. Ishikawa, T. Kawai, N. Kawabata, Y. Matsunaga

GAMMA-RAY BUSTS 1133 73 - + 2009年 [査読有り]

　概要を見る

It is quite important to obtain wide band spectra of gamma-ray bursts (GRBs) at the same time in order to probe the emission processes or the structure of GRBs. An avalanche photo diode (APD) is a compact photon sensor with an internal gain of 100. We have developed an X-ray/gamma-ray detector using a back-illuminated reach-through APD (5x5mm(2)) optically coupled with a conventional CsI(Tl) scintillator, which covers typically from 1 keV to 1 MeV. Further, we developed a 1-dimensional array of the 8/16 APDs (net 16x20 mm(2)) for the purpose of an imaging photon detector to be used in future GRB missions. Here we present the current status and performance of our hybrid detector.

DOI

Scopus
Versatile APD-based PET modules for high resolution, fast medical imaging

J. Kataoka, H. Matsuda, M. Yoshino, T. Miura, F. Nishikido, M. Koizumi, T. Tanaka, H. Ikeda, Y. Ishikawa, N. Kawabata, Y. Matsunaga, S. Kishimoto, H. Kubo

IEEE Nuclear Science Symposium Conference Record 3542 - 3545 2009年 [査読有り]

　概要を見る

We report on the development of versatile APD-based PET modules with time-of-flight capability. The module consists of a LYSO matrix optically coupled with a position-sensitive avalanche photodiode (APD) array, and front-end circuits (FEC) directly connected to the rear-end of the APD package. Each APD device has a monolithic 16x16 (or 8x8) pixel structure with an active area of 1.0 (or 4.0) mm2 for each pixel. Time resolutions of 155 ps and 214 ps (FWHM) were obtained for 1.0 mm2 and 4.0 mm2 APD pixels, respectively, measured by the direct detection of 10 keV X-rays. The FEC carries two identical analog ASICs specifically designed for the APDs in TSMC 0.35 μm CMOS technology. Each ASIC consists of 32-channel charge-sensitive amplifiers, band-pass filters, differentiators, pulse-height and timing discriminators, and two-channel time-to-amplitude converters. The noise characteristic of the ASIC, mounted in a low temperature co-fired ceramics (LTCC) package, is 560 +30 e-/pF with an electric timing resolution of 484 ps (rms). The overall dimension of the module (including APD-array, LYSO matrix and FEC) is 30x30x80 mm3. The variation of signal amplitude was less than 20% among all pixels. The average energy resolutions of 11.7 ± 0.7 % and 13.7 ± 1.1 % were obtained for 662 keV gamma-rays, measured with 8x8 and 16x16 arrays, respectively. An attainable spatial resolution is < 0.8mm (FWHM) for 16x16 array in a reconstructed image. These results suggest the APD-based PET module can be a promising device for future applications, especially for high resolution MRI- and TOF-PET. ©2009 IEEE.

DOI J-GLOBAL

Scopus

1

被引用数

(Scopus)
Development of the X-ray polarimetry small sattellite "TSUBAME"

Toizumi T, Nakamori T, Kataoka J, Tsubuku Y, Yatsu Y, Shimokawabe T, Arimoto M, Kawai N, Omagari K, Ashida H, Matsunaga S

GAMMA-RAY BUSTS 1133 85 - 87 2009年

DOI

Scopus
The soft gamma-ray detector for the ASTRO-H mission

T. Tanaka, R. Blandford, K. Doutsu, T. Endo, T. Enoto, Y. Fukazawa, K. Fukami, T. Fukuyama, Y. Hanabata, J. Harayama, K. Hayashi, K. Hiragi, S. Ishikawa, J. Kataoka, J. Katsuta, T. Kitaguchi, M. Kokubun, M. Koseki, T. Kozu, G. Madejski, K. Makishima, M. Matsuoka, T. Miura, T. Mizuno, S. Nakahira, K. Nakajima, K. Nakazawa, S. Nishino, H. Nishioka, H. Noda, H. Odaka, S. Saito, S. Sasaki, R. Sato, S. Sugimoto, H. Tajima, T. Takahashi, M. Tashiro, Y. Terada, S. Torii, Y. Uchiyama, Y. Umeki, S. Watanabe, Y. Yaji, S. Yamada, K. Yamaoka, M. Yoshino, T. Yuasa

IEEE Nuclear Science Symposium Conference Record 2140 - 2144 2009年 [査読有り]

　概要を見る

The Soft Gamma-ray Detector (SGD) on board ASTRO-H (Japanese next high-energy astrophysics mission) is a Compton telescope with narrow field-of-view, which utilizes Compton kinematics to enhance its background rejection capabilities. It is realized as a hybrid semiconductor detector system which consists of silicon and CdTe (cadmium telluride) detectors. It can detect photons in a wide energy band (50-600 keV) at a background level 10 times better than that of the Suzaku Hard X-ray Detector, and is complimentary to the Hard X-ray Imager on board ASTRO-H with an energy coverage of 5-80 keV. Excellent energy resolution is the key feature of the SGD, allowing it to achieve good background rejection capability taking advantage of good angular resolution. An additional capability of the SGD, its ability to measure gamma-ray polarization, opens up a new window to study properties of gamma-ray emission processes. Here we describe the instrument design of the SGD, its expected performance, and its development status. ©2009 IEEE.

DOI

Scopus

4

被引用数

(Scopus)
Suzaku observation of TeV blazar the 1ES 1218+304: clues on particle acceleration in an extreme TeV blazar

R. Sato, J. Kataoka, T. Takahashi, G. M. Medejski, S. Ruegamer, S. J. Wagner

HIGH ENERGY GAMMA-RAY ASTRONOMY 1085 447 - + 2009年 [査読有り]

　概要を見る

We observed the TeV blazar 1ES 1218+304 with the X-ray astronomy satellite Suzaku in May 2006. At the beginning of the two-day continuous observation, we detected a large flare in which the 5-10 keV flux changed by a factor of similar to 2 on a timescale of 5 x 10(4) s. During the flare, the increase in the hard X-ray flux clearly lagged behind that observed in the soft X-rays, with the maximum lag of 2.3X10(4) s observed between the 0.3-1 keV and 5-10 keV bands, Furthermore we discovered that the temporal profile of the flare clearly changes with energy, being more symmetric at higher energies. From the spectral fitting of multi-wavelength data assuming a one-zone, homogeneous synchrotron self-Compton model, we obtain a magnetic field strength B similar to 0.047 G, an emission region size R = 3.0 x 10(16) cm for an appropriate beaming with a Doppler factor of delta = 20. This value of B is in good agreement with an independent estimate through the model fit to the observed time lag ascribing the energy-dependent variability to differential acceleration timescale of relativistic electrons provided that the gyro-factor xi is 10(5).

DOI

Scopus
Suzaku Observations of Tycho's Supernova Remnant

Toru Tamagawa, Asami Hayato, Satoshi Nakamura, Yukikatsu Terada, Aya Bamba, Junko S. Hiraga, John P. Hughes, Una Hwang, Jun Kataoka, Kenzo Kinugasa, Hideyo Kunieda, Takaaki Tanaka, Hiroshi Tsunemi, Masaru Ueno, Stephen S. Holt, Motohide Kokubun, Emi Miyata, Andrew Szymkowiak, Tadayuki Takahashi, Keisuke Tamura, Daisuke Ueno, Kazuo Makishima

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 61 ( SUPPL. 1 ) S167 - S174 2009年01月 [査読有り]

　概要を見る

Tycho's supernova remnant was observed by the XIS and HXD instruments onboard the Suzaku satellite on 2006 June 26-29 for 92 ks. The spectrum up to 30 keV was well fitted with a two-component model, consisting of a power-law with a photon index of 2.7 and a thermal bremsstrahlung model with a temperature of 4.7 keV. The former component can alternatively be modeled as synchrotron emission from a population of relativistic electrons with an estimated roll-off energy of around 1 keV. In the XIS spectra, in addition to the prominent Fe K alpha line (6.445 keV), we observed for the first time significant K alpha line emission from trace species Cr and Mn at energies of 5.48 keV and 5.95 keV, respectively. Faint K beta lines from Ca (4.56 keV) and Fe (7.11 keV) were also seen. The ionization states of Cr and Mn, based on their line centroids, Lire estimated to be similar to that of Fe K alpha (Fe XV or XVI).

DOI
Study of nonthermal emission from SNR RX J1713.7-3946 with Suzaku

Takaaki Tanaka, Yasunobu Uchiyama, Felix A. Aharonian, Tadayuki Takahashi, Aya Bamba, Junko S. Hiraga, Jun Kataoka, Tetsuichi Kishishita, Motohide Kokubun, Koji Mori, Kazuhiro Nakazawa, Robert Petre, Hiroyasu Tajima, Shin Watanabe

ASTROPHYSICAL JOURNAL 685 ( 2 ) 988 - 1004 2008年10月 [査読有り]

　概要を見る

We present results obtained from a series of observations of the supernova remnant RX J1713.7-3946 by Suzaku. Hard X-rays have been detected up to similar to 40 keV. The hard X-ray spectra are described by a power law with photon indices of similar to 3.0, which is larger than those below 10 keV. The combination of the spatially integrated XIS and HXD spectra clearly reveals a spectral cutoff which is linked to the maximum energy of accelerated electrons. The broad-band coverage of Suzaku allows us to derive, for the first time, the energy spectrum of parent electrons in the cutoff region. The cutoff energy in the X-ray spectrum indicates that the electron acceleration in the remnant proceeds close to the Bohm diffusion limit. We discuss the implications of the spectral and morphological properties of the Suzaku data in the context of the origin of nonthermal emission. The Suzaku X-ray and H.E.S.S. gamma-ray data together hardly can be explained within a pure leptonic scenario. Moreover, the leptonic models require a weak magnetic field, which is inconsistent with the recently discovered X-ray filamentary structures and their short-term variability. The hadronic models with strong magnetic fields provide reasonable fits to the observed spectra, but require special arrangements of parameters to explain the lack of thermal X-ray emission. For morphology studies, we compare the X-ray and TeV gamma-ray surface brightness. We confirm the previously reported strong correlation between X-rays and TeV gamma rays. At the same time, the Suzaku data reveal a deviation from the general tendency, namely, the X-ray emission in the western rims appears brighter than expected from the average X-ray to gamma-ray ratio.

DOI

Scopus

131

被引用数

(Scopus)
Chandra reveals twin X-ray jets in the powerful FR II radio galaxy 3C 353

J. Kataoka, L. Stawarz, D. E. Harris, A. Siemiginowska, M. Ostrowski, M. R. Swain, M. J. Hardcastle, J. L. Goodger, K. Iwasawa, P. G. Edwards

ASTROPHYSICAL JOURNAL 685 ( 2 ) 839 - 857 2008年10月 [査読有り]

　概要を見る

We report X-ray imaging of the powerful FR II radio galaxy 3C 353 using the Chandra X-Ray Observatory. Due to 3C 353's two 4 '' wide and 2' long jets we are able to study in detail the internal structure of the large-scale relativistic outflows at both radio and X-ray photon energies with the subarcsecond spatial resolution provided by the VLA and Chandra instruments. In a 90 ks Chandra observation, we have detected X-ray emission from most radio structures in 3C 353, including the nucleus, the jet and the counterjet, the terminal jet regions (hot spots), and one radio lobe. We show that the detection of the X-ray emission associated with the radio knots and counterknots, which is most likely nonthermal in origin, puts several crucial constraints on the X-ray emission mechanisms in powerful large-scale jets of quasars and FR II sources. In particular, we show that this detection is inconsistent with the inverse-Compton model proposed in the literature and instead implies a synchrotron origin of the X-ray jet photons. We also find that the width of the X-ray counterjet is possibly narrower than that measured in radio bands, that the radio to X-ray flux ratio decreases systematically downstream along the jets, and that there are substantial (kpc-scale) offsets between the positions of the X-ray and radio intensity maxima within each knot, whose magnitudes increase away from the nucleus. We discuss all these findings in the wider context of the physics of extragalactic jets, proposing some particular although not definitive solutions or interpretations for each problem. In general, we find that the synchrotron X-ray emission of extragalactic large-scale jets is not only shaped by the global hydrodynamical configuration of the outflows, but is also likely to be very sensitive to the microscopic parameters of the jet plasma. A complete, self-consistent model for the X-ray emission of extragalactic jets still remains elusive.

DOI

Scopus

36

被引用数

(Scopus)
Suzaku view of powerful gamma-ray quasars

Jun Kataoka

International Journal of Modern Physics D 17 ( 9 ) 1483 - 1489 2008年09月

　概要を見る

We present the results from multiwavelength campaigns of three powerful gamma-ray quasars, PKS 1510-089, RBS 315 and Swift J0746.3+2548, recently organized with Suzaku. The Suzaku observation provided one of the highest S/N X-ray spectra ever reported between 0.3 and 50 keV. For these quasars, the X-ray spectrum is well represented by an extremely hard power-law with photon index Γ ≃ 1.2, but is augmented by an additional soft component apparently below 1 keV for PKS 1510-089, whereas a strong deficit of soft photons is observed in RBS 315. We model the broadband spectra of these powerful quasars and argue that the power of the jet is dominated by protons but with the number of electrons/positrons exceeding the number of protons by a factor ≃ 10. We also argue that an extremely hard X-ray spectra may result from a double power-law form of the injected electrons, with the break energy γbr ≃ 1000 corresponding to the anticipated threshold of diffusive shock acceleration. © 2008 World Scientific Publishing Company.

DOI

Scopus
PoGOLite - A high sensitivity balloon-borne soft gamma-ray polarimeter

Tuneyoshi Kamae, Viktor Andersson, Makoto Arimoto, Magnus Axelsson, Cecilia Marini Bettolo, Claes-Ingvar Bjornsson, Gilles Bogaert, Per Carlson, William Craig, Tomas Ekeberg, Olle Engdegdrd, Yasushi Fukazawa, Shuichi Gunji, Linnea Hjalmarsdotter, Bianca Iwan, Yoshikazu Kanai, Jun Kataoka, Nobuyuki Kawai, Jaroslav Kazejev, Mozsi Kiss, Wlodzimierz Klamra, Stefan Larsson, Grzegorz Madejski, Tsunefumi Mizuno, Johnny Ng, Mark Pearce, Felix Ryde, Markus Suhonen, Hiroyasu TaJima, Hiromitsu Takahashi, Tadayuki Takahashi, Takuya Tanaka, Timothy Thurston, Masaru Ueno, Gary Varneri, Kazuhide Yamamoto, Yuichiro Yamashita, Tomi Ylinen, Hiroaki Yoshida

ASTROPARTICLE PHYSICS 30 ( 2 ) 72 - 84 2008年09月 [査読有り]

　概要を見る

We describe a new balloon-borne instrument (PoGOLite) capable of detecting 10% polarisation from 200 mCrab point-like sources between 25 and 80 keV in one 6-h flight. Polarisation measurements in the soft gamma-ray band are expected to provide a powerful probe into high energy emission mechanisms as well as the distribution of magnetic fields, radiation fields and interstellar matter. Synchrotron radiation, inverse Compton scattering and propagation through high magnetic fields are likely to produce high degrees of polarisation in the energy band of the instrument. We demonstrate, through tests at accelerators, with radioactive sources and through computer simulations, that PoGOLite will be able to detect degrees of polarisation as predicted by models for several classes of high energy sources. At present, only exploratory polarisation measurements have been carried out in the soft gamma-ray band. Reduction of the large background produced by cosmic-ray particles while securing a large effective area has been the greatest challenge. PoGOLite uses Compton scattering and photo-absorption in an array of 217 well-type phoswich detector cells made of plastic and BGO scintillators surrounded by a BGO anticoincidence shield and a thick polyethylene neutron shield. The narrow Held of view (FWHM = 1.25 msr, 2.0 deg x 2.0 deg) obtained with detector cells and the use of thick background shields warrant a large effective area for polarisation measurements (similar to 228 cm(2) at E = 40 keV) without sacrificing the signal-to-noise ratio. Simulation studies for an atmospheric overburden of 3-4 g/cm(2) indicate that neutrons and gamma-rays entering the PDC assembly through the shields are dominant backgrounds. Off-line event selection based on recorded phototube waveforms and Compton kinematics reduce the background to that expected for a similar to 100 mCrab source between 25 and 50 keV. A 6-h observation of the Crab pulsar will differentiate between the Polar Cap/Slot Gap, Outer Gap, and Caustic models with greater than 5 sigma significance; and also cleanly identify the Compton reflection component in the Cygnus X-1 hard state. Long-duration flights will measure the dependence of the polarisation across the cyclotron absorption line in Hercules X-1. A scaled-down instrument will be flown as a pathfinder mission from the north of Sweden in 2010. The first science flight is planned to take place shortly thereafter. (C) 2008 Elsevier B.V. All rights reserved.

DOI

Scopus

46

被引用数

(Scopus)
Suzaku observation of the TeV blazar 1Es 1218+304: Clues on particle acceleration in an extreme TeV blazar

R. Sato, J. Kataoka, T. Takahashi, G. M. Madejski, S. Ruegamer, S. J. Wagner

ASTROPHYSICAL JOURNAL LETTERS 680 ( 1 ) L9 - L12 2008年06月

　概要を見る

We observed the TeV blazar 1ES 1218 + 304 with the X-ray astronomy satellite Suzaku in 2006 May. At the beginning of the 2 day continuous observation, we detected a large flare in which the 5-10 keV flux changed by a factor of similar to 2 on a timescale of 5 x 10(4) s. During the flare, the increase in the hard X-ray flux clearly lagged behind that observed in the soft X-rays, with the maximum lag of 2.3 x 10(4) s observed between the 0.3-1 keV and 5-10 keV bands. Furthermore, we discovered that the temporal profile of the flare clearly changes with energy, being more symmetric at higher energies. From the spectral fitting of multiwavelength data assuming a one-zone, homogeneous synchrotron self-Compton model, we obtain a magnetic field strength B similar to 0.047 G and an emission region size R = 3.0 x 10(16) cm for an appropriate beaming with a Doppler factor of delta = 20. This value of B is in good agreement with an independent estimate through the model fit to the observed time lag ascribing the energy-dependent variability to the differential acceleration timescale of relativistic electrons provided that the gyrofactor xi is 10(5).

DOI

Scopus

27

被引用数

(Scopus)
Evolution of and high-energy emission from GHz-peaked spectrum sources

L. Stawarz, L. Ostorero, M. C. Begelman, R. Moderski, J. Kataoka, S. Wagner

ASTROPHYSICAL JOURNAL 680 ( 2 ) 911 - 925 2008年06月 [査読有り]

　概要を見る

Here we discuss evolution and broadband emission of compact (< kpc) lobes in young radio sources. We propose a simple dynamical description for these objects, consisting of a relativistic jet propagating into a uniform gaseous medium in the central parts of an elliptical host. In the framework of the proposed model we follow the evolution of ultra-relativistic electrons injected from a terminal hot spot of a jet to expanding lobes, taking into account their adiabatic energy losses, as well as radiative cooling. This allows us to discuss the broadband lobe emission of young radio sources. In particular, we argue that the observed spectral turnover in the radio synchrotron spectra of these objects cannot originate from the synchrotron self-absorption process but is most likely due to free-free absorption effects connected with neutral clouds of interstellar medium engulfed by the expanding lobes and photoionized by active centers. We also find a relatively strong and complex high-energy emission component produced by inverse Compton upscattering of various surrounding photon fields by the lobes' electrons. We argue that such high-energy radiation is strong enough to account for several observed properties of GHz-peaked spectrum (GPS) radio galaxies at UV- and X-ray frequencies. In addition, this emission is expected to extend up to GeV (or possibly even TeV) photon energies and can thus be probed by several modern gamma-ray instruments. In particular, we suggest that GPS radio galaxies should constitute a relatively numerous class of extragalactic sources detected by GLAST.

DOI

Scopus

105

被引用数

(Scopus)
Measuring the broad-band X-ray spectrum from 400 eV to 40 keV in the southwest part of the supernova remnant RX J1713.7-3946

Tadayuki Takahashi, Takaaki Tanaka, Yasunobu Uchiyama, Junko S. Hiraga, Kazuhiro Nakazawa, Shin Watanabe, Aya Bamba, John P. Hughes, Hideaki Katagiri, Jun Kataoka, Motohide Kokubun, Katsuji Koyama, Koji Mori, Robert Petre, Hiromitsu Takahashi, Yoko Tsuboi

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 60 ( SPEC. ISS. 1 ) S131 - S140 2008年02月 [査読有り]

　概要を見る

We report on results from Suzaku broadband X-ray observations of the southwest part of the galactic supernova remnant (SNR) RX J1713.7-3946 with an energy coverage of 0.4-40keV. The X-ray spectrum, presumably of synchrotron origin, is known to be completely lineless, making this SNR ideally suited for a detailed study of the X-ray spectral shape formed through efficient particle acceleration at high-speed shocks. With a sensitive hard X-ray measurement from the HXD PIN aboard Suzaku, we determined the hard X-ray spectrum in the 12-40 keV range to be described by a power law with photon index of Gamma = 3.2 +/- 0.2, significantly steeper than the soft X-ray index of Gamma = 2.4 +/- 0.05 measured previously with ASCA and other missions. We find that a simple power law fails to describe the full spectral range of 0.4-40 keV, and instead a power-law with an exponential cutoff with a hard index of Gamma = 1.50 +/- 0.09 and a high-energy cutoff of epsilon(c) = 1.2 +/- 0.3 keV formally provides an excellent fit over the full bandpass. If we use the so-called SRCUT model, as an alternative model, it gives a best-fit rolloff energy of epsilon(roll) = 0.95 +/- 0.04 keV. Together with the TeV gamma-ray spectrum, ranging from 0.3 to 100 TeV, recently obtained by HESS observations, our Suzaku observations of RX J1713.7-3946 provide stringent constraints on the highest-energy particles accelerated in a supernova shock.

DOI
Development status and simulation study of monitor of all-sky x-ray image (MAXI) mission

Hiroshi Tomida, Masaru Matsuoka, Kazuyoshi Kawasaki, Shiro Ueno, Yasuki Adachi, Mitsuhiro Kohama, Motoko Suzuki, Masaki Ishikawa, Haruyoshi Katayama, Tatehiro Mihara, Mutsumi Sugizaki, Naoki Isobe, Hiroshi Tsunemi, Emi Miyata, Nobuyuki Kawai, Jun Kataoka, Atsumasa Yoshida, Kazutaka Yamaoka, Hitoshi Negoro, Motoki Nakajima, Yoshihiro Ueda, Satochi Eguchi, Mikio Morii

Proceedings of SPIE - The International Society for Optical Engineering 7011 2008年

　概要を見る

MAXI (Monitor of All-sky X-ray Image) is a payload on board the International Space Station, and will be launched on April 2009. We report on the current development status on MAXI, in particular on the two types of X-ray camera (GSC and SSC), and the simulation results of the MAXI observation. SSC is a CCD camera. The moderate energy resolution enables us to detect the various emission peak including 0.5 keV oxygen line. The averaged energy resolution at the CCD temperature of -70 deg is 144.5 eV (FWHM) for 5.9 keV X-ray. GSC includes proportional gas counters, which have large X-ray detection area (5350cm2). The averaged position resolution of 1.1mm at 8 keV enable us to determined the celestial position of bright sources within the accuracy of 0.1 degree. The simulation study involving the results of performance test exhibits the high sensitivity of MAXI as designed.

DOI

Scopus
Characterizing X-ray variability of TeV blazars

Jun Kataoka

Proceedings of Science 63 2008年

　概要を見る

In this review, I will discuss how to characterize synchrotron X-ray variability of TeV blazars by using the observed/simulated light curves. Apparently, temporal studies provide independent and complementary information to the spectral studies, but surprisingly little attention has been paid especially for the blazar study. Only exception is a classical argument for presence of “time lag”, which may (or may not) reflect the diffrence of synchrotron cooling timescale. Also very recently, it was suggested that the X-ray variability of TeV blazars indicates a strong red-noise, compared to a fractal, flickering-noise of Seyfert galaxies. Various temporal techniques are proposed in literature, e.g., the power spectrum density (PSD), the structure function (SF), and the discrete correlation function (DCF) and other analysis tools, but special care must be taken if the data are not well sampled and observation is relatively short compared to a characteristic timescale of the system. Also, the situation is being more complicated for low-Earth orbit satellites, e.g., ASCA, RXTE and BeppoSAX, since the light curve inevitably contains “periodic gap” due to the Earth occultation (every 6ksec). I will present detailed approaches to see how the "gap" and the "finite length" of the data affects the results of temporal analysis, and to what extent we can believe in our results. Finally, I will briefly comment on the high-sensitivity X-ray observations with MAXI, that may shed new light on the forthcoming GLAST era.
A study of rapid expanding H II region RCW 89

Y. Yatsu, N. Kawai, J. Kataoka, W. Brinkmann

AIP Conference Proceedings 983 219 - 221 2008年

　概要を見る

In this paper, we present a study of the expanding HII region RCW 89 which is thought to be a part of the radio supernova remnant MSH 15-52 and its associated young 150 ms pulsar B1509-58. We had measured the proper motion of each of the plasma clouds in RCW 89, revealing that these plasma clouds have moved outwards from the SNR center. In order to resolve what is moving at a velocity of ∼5600km/s, we performed spectroscopic analysis of each of the plasma clouds using XMM-Newton and found that each plasma cloud has significantly different redshift. This result strongly suggests that the X-ray emission in RCW 89 comes from the fast expanding SN ejecta. © 2008 American Institute of Physics.

DOI

Scopus
High energy observations of AGN jets and their future prospects

Jun Kataoka

AIP Conference Proceedings 1040 191 - 205 2008年

　概要を見る

In next five years, dramatic progress is anticipated for the AGN studies, as we have two important missions to observe celestial sources in the high energy regime: GLAST and Suzaku. In this talk, I will summarize recent highlights in studies of AGN jets, focusing on the high-sensitivity X-ray observations that may shed new light on the forthcoming GLAST era. I will especially present some examples from most recent Suzaku observations of blazars, which provides important hints for the shock acceleration in sub-pc scale jets, as well as particle content in jets. Then I will focus on the neutral iron-line feature observed in some broad line radio galaxies, as a probe of jet launching and/or the disk-jet connection. Finally, I will discuss new results of large scale (kpc to Mpc) jets recently resolved with Chandra X-ray observatory. Simultaneous monitoring observations in various wavelengths will be particularly valuable for variable blazar sources, allowing the cross correlations of time series as well as detailed modeling of the spectral evolution between the X-ray and gammaray energy bands. Possible impacts of these new observations across the electromagnetic spectrum on various spatial scales are discussed to challenge the long-standing mystery of AGN jet sources. © 2008 American Institute of Physics.

DOI

Scopus

2

被引用数

(Scopus)
Beam test results of the polarized gamma-ray observer, PoGOLite

H. Takahashi, M. Matsuoka, Y. Umeki, H. Yoshida, T. Tanaka, T. Mizuno, Y. Fukazawa, T. Kamae, G. Madejski, H. Tajima, M. Kiss, W. KIamra, S. Larsson, C. Marini Bettolo, M. Pearce, F. Ryde, S. Rydström, K. Kurita, Y. Kanai, M. Arimoto, M. Veno, J. Kataoka, N. Kawai, M. Axelsson, L. Hjalmarsdotter, G. Bogaert, S. Gunji, T. Takahashi, G. Varner, T. Yuasa

IEEE Nuclear Science Symposium Conference Record 732 - 736 2008年

　概要を見る

The Polarized Gamma-ray Observer, PoGOLite, is a balloon experiment with the capability of detecting 10% polarization from a 200 mCrab celestial object in the energy range 25-80 keY. During a beam test at KEK-PF in February 2008, 20 detector units were assembled, and a 50 keY X-ray beam with a polarization degree of ∼90% was irradiated at the center unit. Signals from all 20 units were fed into flightversion electronics consisting of six circuit boards (four waveform digitizer boards, one digital I/O board and one router board) and one microprocessor (SpaceCube), which communicate using a SpaceWire interface. One digitizer board, which can associate up to 8 PDCs, outputs a trigger signal. The digital I/O board handles the trigger and returns a data acquisition request if there is no veto signal (upper or pulse-shape discriminators) from any detector unit. This data acquisition system worked well, and the modulation factor was successfully measured to be ∼34%. These results confirmed the capabilities of both detector and data-acquisition system for a pathfinder flight planned in 2010. ©2008 IEEE.

DOI

Scopus

3

被引用数

(Scopus)
The MAXI mission operation plan

Shiro Ueno, Masaru Matsuoka, Kazuyoshi Kawasaki, Hiroshi Tomida, Yasuki Adachi, Mitsuhiro Kohama, Motoko Suzuki, Masaki Ishikawa, Haruyoshi Katayama, Tatehiro Mihara, Mutsumi Sugizaki, Naoki Isobe, Hiroshi Tsunemi, Emi Miyata, Nobuyuki Kawai, Jun Kataoka, Atsumasa Yoshida, Kazutaka Yamaoka, Hitoshi Negoro, Motoki Nakajima, Mikio Morii, Yoshihiro Ueda, Satoshi Eguchi

Proceedings of SPIE - The International Society for Optical Engineering 7011 2008年

　概要を見る

Monitor of All-sky X-ray Image (MAXI) is an X-ray all-sky monitor, which will be delivered to the International Space Station (ISS) by a space shuttle crew in early 2009, to scan almost the entire sky once every 96 minutes for a mission life of two to five years. The detection sensitivity will be 5 mCrab (5σ level) for a one-day MAXI operation, 2 mCrab for one week, and 1 mCrab for one month, reaching a source confusion limit of 0.2 mCrab in two years. In this paper, brief descriptions are presented for the MAXI mission and payload, and three operation phases, 1) the launch-to-docking phase, 2) the initial in-orbit calibration phase, and 3) the routine operation phase. We also describes the MAXI data product and its release plan for public users.

DOI

Scopus
Shallow decay phase of X-ray afterglows

R. Sato, K. Ioka, K. Toma, T. Nakamura, J. Kataoka, N. Kawai, T. Takahashi

AIP Conference Proceedings 1000 32 - 35 2008年

　概要を見る

We investigated the characteristics of the shallow decay phase in the early X-ray afterglows of GRBs observed by Swift X-Ray Telescope (XRT) during the period of January 2005 to December 2006. We found that the intrinsic break time at the shallow-to-normal decay transition in the X-ray light curve T brk0 is moderately well correlated with the isotropic X-ray luminosity in the end of the shallow decay phase (LX,end) as Tbrk0=(9.39±0.64)×103s(L X,end/1047ergsṡs-1) -0.71±0.03. Using Tbrk0-L X,end relation we have determined the pseudo redshifts of 33 GRBs. We compared the pseudo redshifts of 11 GRBs with measured redshifts and found the rms error to be 0.17 in logz. From this pseudo redshift, we estimate that ∼15% of the Swift GRBs have z>5. The advantages of this distance indicator is that (1) it requires only X-ray afterglow data while other methods such as Amati and Yonetoku correlations require the peak energy (Ep) of the prompt emission, (2) the redshift is uniquely determined without redshift degeneracies unlike the Amati correlation, and (3) the redshift is estimated in advance of deep follow-ups so that possible high redshift GRBs might be selected for detailed observations. © 2008 American Institute of Physics.

DOI

Scopus

1

被引用数

(Scopus)
Performance and current status of Monitor of All-sky X-ray Image on the International Space Station

M. Suzuki, M. Matsuoka, K. Kawasaki, S. Ueno, H. Tomida, M. Kohama, M. Ishikawa, H. Katayama, T. Mihara, N. Isobe, H. Tsunemi, E. Miyata, H. Negoro, M. Nakajima, N. Kawai, J. Kataoka, A. Yoshida, K. Yamaoka, M. Morii

AIP Conference Proceedings 1000 592 - 595 2008年

　概要を見る

Monitor of All-sky X-ray Image (MAXI) will be launched and attached on the International Space Station (ISS) next year. MAXI scans the sky while ISS goes around the Earth and provides an all sky X-ray image every orbit. MAXI has two types of X-ray instruments: gas-proportional counters for 2-30 keV and CCD cameras for 0.5-10 keV. MAXI will be able to transmit alerts to the Internet on X-ray transients including bright X-ray afterglows. © 2008 American Institute of Physics.

DOI

Scopus
X-ray polarimetry small satellite TSUBAME

Arimoto Makoto, Tsubuku Yoshihiro, Toizumi Takahiro, Kobayashi Mitsuyoshi, Yatsu Yoichi, Shimokawabe Takashi, Kataoka Jun, Kawai Nobuyuki, Omagari Kuniyuki, Fujiwara Ken, Konda Yasumi, Tanaka Yohei, Maeno Masaki, Yamanaka Tomio, Ashida Hiroki, Nishida Junichi, Fujihashi Kouta, Ikeda Takuro, Inagawa Shinichi, Miura Yoshiyuki, Matunaga Saburo

GAMMA-RAY BURSTS 2007 1000 607 - + 2008年

DOI

Scopus

4

被引用数

(Scopus)
The PoGOLite balloon-borne soft gamma-ray polarimeter

Kiss M, Larsson S, Arimoto M, Axelsson A, Bettolo C. Marini, Bogaert G, Floren H. -G, Fukazawa Y, Gunji S, Hjalmarsdotter L, Kamae T, Kanai Y, Kataoka J, Kawai N, Klamra W, Kurita K, Madejski G, Mizuno T, Olofsson G, Pearce M, Ryde F, Rydstrom S, Tajima H, Takahashi H, Takahashi T, Tanaka T, Ueno M, Umeki Y, Varner G, Yoshida H

COOL DISCS, HOT FLOWS: THE VARYING FACES OF ACCRETING COMPACT OBJECTS 1054 225 - + 2008年

DOI

Scopus
Hard X-ray Imager (HXI) for the NeXT mission

Motohide Kokubun, Kazuhiro Nakazawa, Shin Watanabe, Yasushi Fukazawa, Jun Kataoka, Hideaki Katagiri, Tsunefumi Mizuno, Kazuo Makishima, Masanori Ohno, Goro Sato, Rie Sato, Hiroyasu Tajima, Tadayuki Takahashi, Toru Tamagawa, Takaaki Ta Na Ka, Makoto Tashiro, Hiromitsu Takahashi, Yukikatsu Terada, Yasunobu Uchiyama, Yuji Urata, Kazutaka Yamaoka, Shin'ichiro Takeda, Tetsuichi Kishishita, Masayoshi Ushio, Jun'ichiro Katsuta, Shin'nosuke Ishikawa, Hirokazu Odaka, Hiroyuki Aono, Souichiro Sugimoto, Yuu Koseki, Takao Kitaguchi, Teruaki Enoto, Shin'ya Yamada, Takayuki Yuasa, Tsuyoshi Ueda, Yuichi Uehara, Sho Okuyama, Hajimu Yasuda, Sho Nishino, Yudai Umeki, Katsuhiro Hayashi, Masayuki Matsuoka, Yuki Ikejiri, Akira Endo, Yuichi Yaji, Natsuki Kodaka, Wataru Iwakiri, Tomomi Kouzu, Takako Sugasawara, Atsushi Harayama, Satoshi Nakahira

Proceedings of SPIE - The International Society for Optical Engineering 7011 2008年 [査読有り]

　概要を見る

The Hard X-ray Imager (HXI) is one of three focal plane detectors on board the NeXT (New exploration X-ray Telescope) mission, which is scheduled to be launched in 2013. By use of the hybrid structure composed of double-sided silicon strip detectors and a cadmium telluride strip detector, it fully covers the energy range of photons collected with the hard X-ray telescope up to 80 keV with a high quantum efficiency. High spatial resolutions of 400 micron pitch and energy resolutions of 1-2 keV (FWMH) are at the same time achieved with low noise front-end ASICs. In addition, thick BGO active shields compactly surrounding the main detection part, as a heritage of the successful performance of the Hard X-ray Detector (HXD) on board Suzaku satellite, enable to achive an extremely high background reduction for the cosmic-ray particle background and in-orbit activation. The current status of hardware development including the design requirement, expected performance, and technical readinesses of key technologies are summarized.

DOI

Scopus

26

被引用数

(Scopus)
Multiwavelength observations of the powerful gamma-ray quasar PKS 1510-089: Clues on the jet composition

J. Kataoka, G. Madejski, M. Sikora, P. Roming, M. M. Chester, D. Grupe, Y. Tsubuku, R. Sato, N. Kawai, G. Tosti, D. Impiombato, Y. Y. Kovalev, Y. A. Kovalev, P. G. Edwards, S. J. Wagner, R. Moderski, L. Stawarz, T. Takahashi, S. Watanabe

ASTROPHYSICAL JOURNAL 672 ( 2 ) 787 - 799 2008年01月

　概要を見る

We present the results from a multiwavelength campaign conducted in 2006 August of the powerful gamma-ray quasar PKS 1510-089 (z = 0.361). This campaign commenced with a deep Suzaku observation lasting 3 days for a total exposure time of 120 ks and continued with Swift monitoring over 18 days. Besides Swift observations, the campaign included ground-based optical and radio data and yielded a quasi-simultaneous broadband spectrum from 10(9) to 10(19) Hz. The Suzaku observation provided a high signal-to-noise ratio X-ray spectrum, which is well represented by an extremely hard power law with a photon index of Gamma similar or equal to 1.2, augmented by a soft component apparent below 1 keV, which is well described by a blackbody model with a temperature of kT similar or equal to 0.2 keV. Monitoring by Suzaku revealed temporal variability that differs between the low- and high-energy bands, again suggesting the presence of a second, variable component in addition to the primary power-law emission. We model the broadband spectrum, assuming that the high-energy spectral component results from Comptonization of infrared radiation produced by hot dust located in the surrounding molecular torus. The adopted internal shock scenario implies that the power of the jet is dominated by protons, but with a number of electrons and/or positrons that exceeds the number of protons by a factor of similar to 10. We also find that inhomogeneities responsible for the shock formation prior to the collision may produce bulk Compton radiation, which can explain the observed soft X-ray excess and possible excess at similar to 18 keV. We note, however, that the bulk Compton interpretation is not unique, as discussed briefly in the text.

DOI

Scopus

104

被引用数

(Scopus)
Oxygen line mapping of SN 1006 with Suzaku

Aya Bamba, Hiroya Yamaguchi, KatsuJi Koyama, Junko S. Hiraga, Steve Holt, John P. Hughes, Hideaki Katagiri, Jun Kataoka, Satoru Katsuda, Shunji Kitamoto, Motohide Kokubun, Hironori Matsumoto, Emi Miyata, Koji Mori, Hiroshi Nakajima, Masanobu Ozaki, Rob Petre, Akiko Sekiguchi, Tadayuki Takahashi, Takaaki Tanaka, Yukikatsu Terada, Hiroshi Tomida, Yohko Tsuboi, Masahiro Tsujimoto, Hiroshi Tsunemi, Yasunobu Uchiyama, Masaru Ueno, Shin Watanabe

ADVANCES IN SPACE RESEARCH 41 ( 3 ) 411 - 415 2008年 [査読有り]

　概要を見る

SN 1006 is one of the supernova remnants (SNRs) with relatively low-temperature electrons, considering the young age of just 1000 years. We carried out SN 1006 mapping observations with the X-ray Imaging Spectrometers (XIS) and the Hard X-ray Detector (HXD) onboard Suzaku, the fifth Japanese X-ray satellite. Thanks to the excellent spectral resolution of XIS in the soft X-ray band, H-like and He-like oxygen emission lines were clearly detected, and we could make a map of the line intensity, and as well as a flux and the photon index of nonthermal component. We found that these parameters have spatial dependences from region to region in the SNR; the north region is bright in nonthermal, while dim in thermal; the east region is bright in both nonthermal and thermal; the inner region shows dim nonthermal and bright thermal emission. The photon index is the smallest in the north region. (C) 2007 Published by Elsevier Ltd on behalf of COSPAR.

DOI

Scopus

3

被引用数

(Scopus)
Environmental tests of the flight GLAST LAT tracker towers

R. Bagagli, L. Baldini, R. Bellazzini, G. Barblellini, F. Belli, T. Borden, A. Brez, M. Brigida, G. A. Caliandro, C. Cecchi, J. Cohen-Tanugi, A. De Angelis, P. Drell, C. Favuzzi, P. Fusco, F. Gargano, S. Germani, N. Giglietto, F. Giordano, J. Goodman, T. Himel, M. Hirayama, R. P. Johnson, H. Katagiri, J. Kataoka, N. Kawai, W. Kroeger, J. Ku, M. Kuss, L. Latronico, F. Longo, F. Loparco, P. Lubrano, B. Marangelli, F. Marcucci, M. Marchetti, M. M. Massai, M. N. Mazziotta, M. Minori, M. Minuti, N. Mirizzi, M. Mongelli, C. Monte, A. Morselli, D. Nelson, M. Nordby, N. Omodei, M. Pepe, M. Pesce-Rollins, S. Raino, R. Rando, M. Razzano, D. Rich, G. Scolieri, C. Sgro, G. Spandre, P. Spinelli, M. Sugizaki, H. Takahashi, A. Tenze, C. Young

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 584 ( 2-3 ) 358 - 373 2008年01月 [査読有り]

　概要を見る

The Gamma-ray Large Area Space telescope (GLAST) is a gamma-ray satellite scheduled for launch in 2008. Before the assembly of the Tracker subsystem of the Large Area Telescope (LAT) science instrument of GLAST, every component (tray) and module (tower) has been subjected to extensive ground testing required to ensure successful launch and on-orbit operation. This paper describes the sequence and results of the environmental tests performed on an engineering model and all the flight hardware of the GLAST LAT Tracker. Environmental tests include vibration testing, thermal cycles and thermal-vacuum cycles of every tray and tower as well as the verification of their electrical performance. (C) 2007 Elsevier B.V. All rights reserved.

DOI

Scopus

3

被引用数

(Scopus)
In-flight status of the X-ray observatory Suzaku

T. Dotani, K. Mitsuda, M. Bautz, H. Inoue, R. L. Kelley, K. Koyama, H. Kunieda, K. Makishima, Y. Ogawara, R. Petre, T. Takahashi, H. Tsunemi, N. E. White, N. Anabuki, L. Angelini, K. Arnaud, H. Awaki, A. Bamba, K. Boyce, G. V. Brown, K. W. Chan, J. Cottam, J. Doty, K. Ebisawa, Y. Ezoe, A. C. Fabian, E. Figueroa, R. Fujimoto, Y. Fukazawa, T. Furusho, A. Furuzawa, K. Gendreau, R. E. Griffiths, Y. Haba, K. Hamaguchi, I. Harrus, G. Hasinger, I. Hatsukade, K. Hayashida, P. J. Henry, J. S. Hiraga, S. S. Holt, A. Hornschemeier, J. P. Hughes, U. Hwang, M. Ishida, Y. Ishisaki, N. Isobe, M. Itoh, N. Iyomoto, S. M. Kahn, T. Kamae, H. Katagiri, J. Kataoka, H. Katayama, N. Kawai, M. Kawaharada, C. Kilbourne, K. Kinugasa, S. Kissel, S. Kitamoto, M. Kohama, T. Kohmura, M. Kokubun, T. Kotani, J. Kotoku, A. Kubota, G. M. Madejski, Y. Maeda, F. Makino, A. Markowitz, C. Matsumoto, H. Matsumoto, M. Matsuoka, K. Matsushita, D. McCammon, T. Mihara, K. Misaki, E. Miyata, T. Mizuno, K. Mori, H. Mori, M. Morii, H. Moseley, K. Mukai, H. Murakami, T. Murakami, R. Mushotzky, F. Nagase, M. Namiki, H. Negoro, K. Nakazawa, J. A. Nousek, T. Okajima, Y. Ogasaka, T. Ohashi, T. Oshima, N. Ota, M. Ozaki, H. Ozawa

IEEE Nuclear Science Symposium Conference Record 4 2526 - 2531 2007年12月 [査読有り]

　概要を見る

We report in-flight status of the X-ray detectors on board the Suzaku observatory, the 5th X-ray astronomy satellite of Japan launched on July 10, 2005. Suzaku is equipped with two types of Instruments: one is the X-ray Imaging Spectrometers (XISs) and the other is Hard X-ray Detector (HXD). XIS utilizes the X-ray CCD camera in combination with the grazing-incidence X-ray telescope. HXD is a non-imaging, hybrid detector utilizing Si PIN diodes and GSO/BGO phoswich counters. Suzaku takes a low-earth, circular orbit with an altitude of 560 km and an inclination of 31 deg. This means that Suzaku goes through the south atlantic anomaly about 1/3 of its revolutions. This has a large impact on the in-flight performance of XIS and HXD, which is reported in detail in the present paper. © 2007 IEEE.

DOI

Scopus
Temperature effects in reverse-type avalanche photodiodes

Mitsuhiro Sato, Takayuki Yanagida, Akira Yoshikawa, Yoichi Yatsu, Jun Kataoka, Fumio Saito

IEEE Nuclear Science Symposium Conference Record 2 1491 - 1493 2007年12月

　概要を見る

These The present paper shows ionization coefficient ratios, k-values, k1and keff, of reverse-type Si avalanche photodiode. Both of keffand k1, tend to increase when APDs are cooled down. The results for keffare 0.0023 ± 0.0002 at 20 °C, 0.0027 ± 0.0003 at 0 °C, and 0.0049 ±0.0007 at -20 °C. With the result of k1, temperature dependency of k-values Indicates mean free paths of the carriers for phonon scattering shows different temperature dependency, which is considered to reflect the inner structure of APDs. © 2007 IEEE.

DOI

Scopus

2

被引用数

(Scopus)
Hole multiplication in a reverse-type avalanche photodiode

Mitsuhiro Sato, Takayuki Yanagida, Akira Yoshikawa, Yoichi Yatsu, Jun Kataoka, Fumio Saito

IEEE Nuclear Science Symposium Conference Record 2 1486 - 1490 2007年12月

　概要を見る

This paper reports on hole multiplication processes, detected in a reverse-type avalanche photodiode (APD), Hamamatsu Photonics type S8664-55, which has a light sensitive area of 5 × 5 mm and a depletion layer thickness of ∼ 40 μm. When the APD was irradiated from a Am isotope, the 13.9 keV and 17.6 keV X-rays produced spectral peaks, whose pulse height depended strongly on the bias voltage, whereas 57.5 keV photons produced another peak, whose the pulse height was much less bias sensitive. The former are identified with electron multiplication signals, whereas the latter with those due to hole multiplication. By measuring the electron and hole multiplication gains as a function of the bias voltage, the ratio of hole and electron ionization probabilities was determined as 0.0130 ± 0.0010 at 20 °C, and 0.0153 ±0.0010 at -20 °C. © 2007 IEEE.

DOI

Scopus

2

被引用数

(Scopus)
Reverse-type avalanche photodiode for scintillation detection and intrinsic energy resolution of BGO and GSO:Ce

Mitsuhiro Sato, Takayuki Yanagida, Akira Yoshikawa, Yousuke Yatsu, Jun Kataoka, Yoshitaka Ishikawa, Fumio Saito

IEEE Nuclear Science Symposium Conference Record 3 2023 - 2032 2007年12月

　概要を見る

In this paper we present a summary of a study of reverse-type avalanche photodiodes (APDs) used as scintillation detectors for X- and γ-ray spectroscopy. The energy resolution of the APDs was evaluated by varying the avalanche gain, M, in the range from 1 to 200. The best energy resolution recorded for the 662 keV137Cs γ-ray photoabsorption peak was 8.3 ± 0.5 % using a 5 × 5 × 5 mm3BGO crystal coupled to a S8664-55 APD with a 5 × 5 mm2light sensitive window, manufactured by Hamamatsu Photonics, Inc. The measurement was made with a gain of 20 and at a temperature of -20 °C. The main advantage of this method is that an accurate value for the intrinsic resolution of the crystal can be easily obtained by subtracting the contribution to the energy resolution from circuit noise and the electron-hole pair statistics. The intrinsic energy resolution of the BGO crystal sample at 662 keV was found to be 6.5 ± 0.5%. The observed intrinsic energy resolution of BGO as a function of energy shows the same relationship as that shown in other published works. With this method the intrinsic energy resolution of GSO (Ce 0.5 % mol) was also measured. While the intrinsic energy resolution of BGO shows an energy dependence proportional to E-1/2, GSO has a step-like characteristic, with the energy resolution increasing from ∼100 keV up to ∼500 keV. © 2007 IEEE.s.

DOI

Scopus

10

被引用数

(Scopus)
Performance assessment study of the balloon-borne astronomical soft gamma-ray polarimeter PoGOLite

Arimoto M, Kanai Y, Ueno M, Kataoka J, Kawai N, Tanaka T, Yamamoto K, Takahashi H, Mizuno T, Fukazawa Y, Axelsson M, Kiss M, Bettolo C. Marini, Carlson P, Klamra W, Pearce M, Chen P, Craig B, Kamae T, Madejski G, Ng J. S. T, Rogers R, Tajima H, Thurston T. S, Saito Y, Takahashi T, Gunji S, Bjornsson Ca, Larsson S, Ryde F, Bogaert G, Varner G

PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES 40 ( 2 ) 438 - 441 2007年12月 [査読有り]

DOI

Scopus
Design and initial tests of the Tracker-converter of the Gamma-ray Large Area Space Telescope

W. B. Atwood, R. Bagagli, L. Baldini, R. Bellazzini, G. Barbiellini, F. Belli, T. Borden, A. Brez, M. Brigida, G. A. Caliandro, C. Cecchi, J. Cohen-Tanugi, A. De Angelis, P. Drell, C. Favuzzi, Y. Fukazawa, P. Fusco, F. Gargano, S. Germani, R. Giannitrapani, N. Giglietto, F. Giordano, T. Himel, M. Hirayama, R. P. Johnson, H. Katagiri, J. Kataoka, N. Kawai, W. Kroeger, M. Kuss, L. Latronico, F. Longo, F. Loparco, P. Lubrano, M. M. Massai, M. N. Mazziotta, M. Minuti, T. Mizuno, A. Morselli, D. Nelson, M. Nordby, T. Ohsugi, N. Omodei, M. Ozaki, M. Pepe, S. Raino, R. Rando, M. Razzano, D. Rich, H. F. -W. Sadrozinski, G. Scolieri, C. Sgro, G. Spandre, P. Spinelli, M. Sugizaki, H. Tajima, H. Takahashi, T. Takahashi, S. Yoshida, C. Young, M. Ziegler

ASTROPARTICLE PHYSICS 28 ( 4-5 ) 422 - 434 2007年12月 [査読有り]

　概要を見る

The Tracker subsystem of the Large Area Telescope (LAT) science instrument of the Gamma-ray Large Area Space Telescope (GLAST) mission has been completed and tested. It is the central detector subsystem of the LAT and serves both to convert an incident gamma-ray into an electron-positron pair and to track the pair in order to measure the gamma-ray direction. It also provides the principal trigger for the LAT. The Tracker uses silicon strip detectors, read out by custom electronics, to detect charged particles. The detectors and electronics are packaged, along with tungsten converter foils, in 16 modular, high-precision carbon-composite structures. It is the largest silicon-strip detector system ever built for launch into space, and its aggressive design emphasizes very low power consumption, passive cooling, low noise, high efficiency, minimal dead area, and a structure that is highly transparent to charged particles. The test program has demonstrated that the system meets or surpasses all of its performance specifications as well as environmental requirements. It is now installed in the completed LAT, which is being prepared for launch in early 2008. (c) 2007 Elsevier B.V. All rights reserved.

DOI

Scopus

64

被引用数

(Scopus)
Construction, test and calibration of the GLAST silicon tracker

C. Sgro, W. B. Atwood, L. Baldini, G. Barbiellini, R. Bellazzini, F. Belli, E. Bonamente, T. Borden, J. Bregeon, A. Brez, M. Brigida, G. A. Caliandro, C. Cecchi, J. Cohen-Tanugi, A. De Angelis, P. Drell, C. Favuzzi, Y. Fukazawa, P. Fusco, F. Gargano, S. Germani, N. Giglietto, F. Giordano, T. Himel, M. Hirayama, R. P. Johnson, H. Katagiri, J. Kataoka, N. Kawai, W. Kroeger, M. Kuss, L. Latronico, F. Longo, F. Loparco, P. Lubrano, M. M. Massai, M. N. Mazziotta, M. Minuti, T. Mizuno, A. Morselli, D. Nelson, M. Nordby, T. Ohsugi, N. Omodei, M. Ozaki, M. Pepe, S. Raino, R. Rando, M. Razzano, D. Rich, H. F. -W. Sadrozinski, G. Scolieri, G. Spandre, P. Spinelli, M. Sugizaki, H. Tajima, H. Takahashi, T. Takahashi, S. Yoshida, C. Young, M. Ziegler

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 583 ( 1 ) 9 - 13 2007年12月 [査読有り]

　概要を見る

The Gamma-ray Large Area Space Telescope represents a great advance in space application of silicon detectors. With a surface of 80 m(2) and about 1 M readout channels it is the largest silicon tracker ever built for a space experiment.
GLAST is an astro-particle mission that will study the mostly unexplored, high energy (20 MeV-300 GeV) spectrum coming from active sources or diffused in the Universe. The detector integration and test phase is complete. The full instrument underwent environmental testing and the spacecraft integration phase has just started: the launch is foreseen in late 2007. In the meanwhile the spare modules are being used for instrument calibration and performance verification employing the CERN accelerator complex. A Calibration Unit has been exposed to photon, electron and hadron beams from a few GeV up to 300 GeV. We report on the status of the instrument and on the calibration campaign. (C) 2007 Elsevier B.V. All rights reserved.

DOI

Scopus

3

被引用数

(Scopus)
Measuring energy dependent polarization in soft gamma-rays using compton scattering in PoGOLite

M. Axelsson, O. Engdegard, F. Ryde, S. Larsson, M. Pearce, L. Hjalmarsdotter, M. Kiss, C. Marini Bettolo, M. Arimoto, C. -I. Bjornsson, P. Carlson, Y. Fukazawa, T. Kamae, Y. Kanai, J. Kataoka, N. Kawal, W. Klamra, G. Madejski, T. Mizuno, J. Ng, H. Tajima, T. Takahashi, T. Tanaka, M. Ueno, G. Varner, K. Yamamoto

ASTROPARTICLE PHYSICS 28 ( 3 ) 327 - 337 2007年11月 [査読有り]

　概要を見る

Linear polarization in X-and gamma-rays is an important diagnostic of many astrophysical sources, foremost giving information about their geometry, magnetic fields, and radiation mechanisms. However, very few X-ray polarization measurements have been made, and then only mono-energetic detections, whilst several objects are assumed to have energy dependent polarization signatures. In this paper, we investigate whether detection of energy dependent polarization from cosmic sources is possible using the Compton technique, in particular with the proposed PoGOLite balloon-experiment, in the 25-100 keV range. We use Geant4 simulations of a PoGOLite model and input photon spectra based on Cygnus X-1 and accreting magnetic pulsars (100 mCrab). Effective observing times of 6 and 35 h were simulated, corresponding to a standard and a long duration flight, respectively. Both smooth and sharp energy variations of the polarization are investigated and compared to constant polarization signals using chi-square statistics. We can reject constant polarization, with energy, for the Cygnus X-1 spectrum (in the hard state), if the reflected component is assumed to be completely polarized, whereas the distinction cannot be made for weaker polarization. For the accreting pulsar, constant polarization can be rejected in the case of polarization in a narrow energy band with at least 50% polarization, and similarly for a negative step distribution from 30% to 0% polarization. (c) 2007 Elsevier B.V. All rights reserved.

DOI

Scopus

6

被引用数

(Scopus)
Development of wideband X-ray and gamma-ray spectrometer using transmission-type, large-area APD

S. Tanaka, J. Kataoka, Y. Kanai, Y. Yatsu, M. Arimoto, M. Koizumi, N. Kawai, Y. Ishikawa, S. Kawai, N. Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 582 ( 2 ) 562 - 568 2007年11月 [査読有り]

　概要を見る

The avalanche photodiode (APD) is a high-performance and compact light sensor recently applied in various fields of experimental physics. Among several types of APDs, the reach-through APD offers an advantage in direct X-ray detection, thanks to its thick depletion layer (>= 100 mu m) in front of the amplification region. This type of APD is also sensitive to weak scintillation light from gamma ray scintillators with a high quantum efficiency of similar to 80% (at lambda similar or equal to 500 nm). In this paper, we propose a novel design of a compact X-rayto-gamma-ray detector widely applicable between 1 keV and several hundreds of keV. The prototype consists of a reach-through APD (transmission type) optically coupled with a cubic CsI(T1) crystal 4 x 4 x 4mm(3) in size. By applying the pulse shape discrimination technique to the APD output, we successfully discriminated the X-ray signals directly detected within the APD (1-40 keV), and gamma ray signals absorbed in a CsI(T1) scintillator (10-800 keV) located immediately behind the APD. Optimum FWHM energy resolutions of 15.1 +/- 0.2%, 6.6 +/- 0.4%, and 7.6 +/- 0.1% were obtained for 5.9 keV X-rays, 32 keV X-rays, and 662 keV gamma rays, respectively, measured at +20 degrees C. This stacked configuration is viable for various future applications in space science and nuclear medicine. (c) 2007 Elsevier B.V. All rights reserved.

DOI

Scopus

11

被引用数

(Scopus)
The Suzaku observation of the nucleus of the radio-loud active galaxy Centaurus A: Constraints on abundances of the accreting material

A. Markowitz, T. Takahashi, S. Watanabe, K. Nakazawa, Y. Fukazawa, M. Kokubun, K. Makishima, H. Awaki, A. Bamba, N. Isobe, J. Kataoka, G. Madejski, R. Mushotzky, T. Okajima, A. Ptak, J. N. Reeves, Y. Ueda, T. Yamasaki, T. Yaqoob

ASTROPHYSICAL JOURNAL 665 ( 1 ) 209 - 224 2007年08月 [査読有り]

　概要を見る

A Suzaku observation of the nucleus of the radio-loud AGN Centaurus A in 2005 has yielded a broadband spectrum spanning 0.3-250 keV. The net exposure times after screening were 70 ks per X-ray Imaging Spectrometer (XIS) camera, 60.8 ks for the Hard X- ray Detector (HXD) PIN, and 17.1 ks for the HXD GSO. The hard X- rays are fit by two power laws of the same slope, absorbed by columns of 1.5 and 7 x 10(23) cm(-2), respectively. The spectrum is consistent with previous suggestions that the power-law components are X- ray emission from the subparsec VLBI jet and from Bondi accretion at the core, but it is also consistent with a partial-covering interpretation. The soft band is dominated by thermal emission from the diffuse plasma and is fit well by a two-temperature VAPEC model, plus a third power-law component to account for scattered nuclear emission, jet emission, and emission from X- ray binaries and other point sources. Narrow fluorescent emission lines from Fe, Si, S, Ar, Ca, and Ni are detected. The Fe K proportional to line width yields a 200 lt-day lower limit on the distance from the black hole to the line-emitting gas. Fe, Ca, and S K-shell absorption edges are detected. Elemental abundances are constrained via absorption edge depths and strengths of the fluorescent and diffuse plasma emission lines. The high metallicity ([Fe/H] = +0.1) of the circumnuclear material suggests that it could not have originated in the relatively metal-poor outer halo unless enrichment by local star formation has occurred. Relative abundances are consistent with enrichment from Type II and Ia supernovae.

DOI

Scopus

52

被引用数

(Scopus)
Low-energy cutoffs and hard X-ray spectra in high-z radio-loud quasars: The Suzaku view of RBS 315

F. Tavecchio, L. Maraschi, G. Ghisellini, J. Kataoka, L. Foschini, R. M. Sambruna, G. Tagliaferri

ASTROPHYSICAL JOURNAL 665 ( 2 ) 980 - 989 2007年08月 [査読有り]

　概要を見る

We present the results from the Suzaku observation of the powerful radio-loud quasar RBS 315 (z = 2.69), for which a previous XMM-Newton observation showed an extremely flat X-ray continuum up to 10 keV ( photon index Gamma = 1.26) and indications of strong intrinsic absorption (N-H similar to 10(22) cm(-2), assuming neutral gas). The instrument for hard X-rays, HXD/PIN, allows us a detection of the source up to 50 keV. The broadband continuum (0.5-50 keV) can be well modeled with a power law with slope Gamma = 1.5 (definitively softer than the continuum measured by XMM-Newton) above 1 keV with strong deficit of soft photons. The low-energy cutoff can be well fitted, either with intrinsic absorption ( with column density N-H similar to 10(22) cm(-2) in the quasar rest frame) or with a break in the continuum, with an extremely hard (Gamma = 0.7) power law below 1 keV. We construct the spectral energy distribution of the source, using also optical-UV measurements obtained through a quasi-simultaneous observation with UVOT on board Swift observation. The shape of the SED is similar to that of other flat-spectrumradio quasars (FSRQs) with similar power, making this source an excellent candidate for the detection in gamma-rays by the Gamma-Ray Large Area Space Telescope ( GLAST). We model the SED with the synchrotron inverse Compton model usually applied to FSRQs, showing that the deficit of soft photons can be naturally interpreted as due to an intrinsic curvature of the spectrum near the low-energy end of the IC component, rather than to intrinsic absorption, although the latter possibility cannot be ruled out. We propose that in at least a fraction of the radio-loud QSOs at high redshift, the cutoff in the soft X-ray band can be explained in a similar way. Further studies are required to distinguish between the two alternatives.

DOI

Scopus

50

被引用数

(Scopus)
Probing the disk-jet connection of the radio galaxy 3C 120 observed with Suzaku

Jun Kataoka, James N. Reeves, Kazushi Iwasawa, Alex G. Markowitz, Richard F. Mushotzky, Makoto Arimoto, Tadayuki Takahashi, Yoshihiro Tsubuku, Masayoshi Ushio, Shin Watanabe, Luigi C. Gallo, Greg M. Madejski, Yuichi Terashima, Naoki Isobe, Makoto S. Tashiro, Takayoshi Kohmura

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 ( 2 ) 279 - 297 2007年04月 [査読有り]

　概要を見る

We report on deep (40 ks x 4) observations of the bright broad line radio galaxy 3C 120 using Suzaku. The observations were spaced one week apart, and sampled a range of continuum fluxes. An excellent broadband spectrum was obtained over two decades of frequency (0.6 to 50 keV) within each 40 ks exposure. We clearly resolved the iron K emission-line complex, finding that it consists of a narrow K alpha core (sigma similar or equal to 110 eV or an EW of 60 eV), a 6.9 keV line, and an underlying broad iron line. Our confirmation of the broad line contrasts with the XMM-Newton observation in 2003, where the broad line was not required. The most natural interpretation of the broadline is iron Kline emission from a face-on accretion disk that is truncated at similar to 10 r(g). Above 10 keV, a relatively weak Compton hump was detected (reflection fraction of R similar or equal to 0.6), superposed on the primary X-ray continuum of Gamma similar or equal to 1.75. Thanks to the good photon statistics and low background of the Suzaku data, we clearly confirm the spectral evolution of 3C 120, whereby the variability amplitude decreases with increasing energy. More strikingly, we discovered that the variability is caused by a steep power-law component of Gamma similar or equal to 2.7, possibly related to non-thermal jet emission. We discuss our findings in the context of similarities and differences between radio-loud/quiet objects.

DOI

Scopus

62

被引用数

(Scopus)
22pZJ-14 全天X線監視装置MAXI/GSCのソフトウエアの開発(22pZJ X線・γ線,宇宙線・宇宙物理領域)

鈴木素子, 松岡勝, 川崎一義, 上野史郎, 冨田洋, 石川真木, 小浜光洋, 宮川雄大, 三原建弘, 磯部直樹, 河合誠之, 片岡淳, 田中識史, 吉田篤正, 根来均, 中島基樹, 森井幹雄

日本物理学会講演概要集 62.2.1 111 2007年

DOI CiNii
A Suzaku observation of the low-ionization Fe-line emission from RCW 86

Masaru Ueno, Rie Sato, Jun Kataoka, Ilana Harrus, Robert Petre

Progress of Theoretical Physics Supplement ( 169 ) 84 - 87 2007年

　概要を見る

The newly operational X-ray satellite Suzaku observed the southwestern quadrant of the supernova remnant (SNR) RCW 86 in February 2006 to study the nature of the 6.4 keV emission line. The new data localize it for the first time; most of the line emission is adjacent and interior to the forward shock and not at the locus of the continuum hard emission. We also report the first detection of a 7.1 keV line that we interpret as the Kβ emission from low-ionization iron. The Fe-K line features are consistent with a non-equilibrium plasma of Fe-rich ejecta with net > 109 cm-3 s and kTe ∼ 5 keV. This combination of low net and high kTe suggests collisionless electron heating in an SNR shock. The Fe Ka line shows evidence for intrinsic broadening, with a width of 47 (34-59) eV (99% error region). The difference of the spatial distributions of the hard continuum above 3 keV and the Fe-K line emission support a synchrotron origin for the hard continuum.

DOI

Scopus
Millenium study of SN 1006 with Suzaku

Aya Bamba, Hiroya Yamaguchi, Katsuji Koyama, Junko S. Hiraga, Steve Holt, John P. Hughes, Hideaki Katagiri, Jun Kataoka, Shunji Kitamoto, Motohide Kokubun, Hironori Matumoto, Emi Miyata, Koji Mori, Hiroshi Nakajima, Masanobu Ozaki, Robert Petre, Akiko Sekiguchi, Tadayuki Takahashi, Takaaki Tanaka, Yukikatsu Terada, Hiroshi Tomida, Hiroshi Tsunemi, Yohko Tsuboi, Masahiro Tsujimoto, Yasunobu Uchiyama, Masaru Ueno, Shin Watanabe

Progress of Theoretical Physics Supplement ( 169 ) 142 - 145 2007年

　概要を見る

SN 1006 is the milestone of understanding the acceleration mechanism of cosmic rays, and this year is the millennium year for the remnant. We carried out SN 1006 mapping observations with the X-ray Imaging Spectrometers (XIS) onboard Suzaku satellite. Thanks to the excellent spectral response of XIS, K emission lines from highly ionized oxygen were clearly resolved. The intensity maps of these lines have been made additional to the intensity and photon index maps of the nonthermal component. We discovered that regions with strong and hard nonthermal component has weak thermal emission. The north rim of the SNR has the hardest nonthermal component. These facts might have information of efficient cosmic ray acceleration and background plasma.

DOI

Scopus
Wide-range multiwavelength observations of northern TeV blazars with MAGIC/HESS, Suzaku and KVA

M. Hayashida, S. Rügamer, D. Mazin, R. Firpo, K. Mannheim, F. Tavecchio, M. Teshima, D. Horns, L. Costamante, S. Schwarzburg, S. Wagner, T. Takahashi, J. Kataoka, G. Madejski, R. Sato, M. Ushio

Proceedings of the 30th International Cosmic Ray Conference, ICRC 2007 3 ( OG PART 2 ) 1029 - 1032 2007年

　概要を見る

We conducted multiwavelength observations of the northern TeV blazars, Mkn501 and Mkn421, employing the ground-based γ-ray telescopes MAGIC and HESS, the Suzaku X-ray satellite and the KVA optical telescope. The observations for Mkn501 were performed in July 2006. The source showed one of the lowest fluxes both in very high energy (VHE) γ-ray and X-ray. No significant flux variability could be found in the VHE band while an overall increase of about 50% on a 1-day time scale could be seen in the light curve of the X-ray flux. A one-zone synchrotron self-Compton model can well describe our simultaneous spectral data of the VHE γ-ray and the X-ray emissions of Mkn501 in the quiescent state. The simultaneous observations of Mkn421 were carried out in April 2006. The source was clearly detected in all observations and showed a high state of activity both in VHE γ-ray and X-ray.
An overview of MAXI onboard JEM-EF of the international space station

M. Matsuoka, K. Kawasaki, S. Ueno, H. Tomida, M. Kohama, M. Ishikawa, H. Katayama, M. Suzuki, T. Miyakawa, T. Mihara, N. Isobe, H. Tsunemi, E. Miyata, H. Negoro, M. Nakajima, N. Kawai, J. Kataoka, A. Yoshida, K. Yamaoka, M. Morii

Proceedings of SPIE - The International Society for Optical Engineering 6686 2007年

　概要を見る

MAXI is the first payload to be attached on JEM-EF (Kibo exposed facility) of ISS. It provides an all sky X-ray image every ISS orbit. If MAXI scans the sky during one week, it could make a milli-Crab X-ray all sky map excluding bright region around the sun. Thus, MAXI does not only inform X-ray novae and transients rapidly to world astronomers if once they occur, but also observes long-term variability of Galactic and extra-Galactic X-ray sources. MAXI also provides an X-ray source catalogue at that time with diffuse cosmic X-ray background. MAXI consists of two kinds of detectors, position sensitive gas-proportional counters for 2-30 keV X-rays and CCD cameras for 0.5-10 keV X-rays. All instruments of MAXI are now in final phase of pre-launching tests of their flight modules. We are also carrying out performance tests for X-ray detectors and collimators. Data processing and analysis software including alert system on ground are being developed by mission team. In this paper we report an overview of final instruments of MAXI and capability of MAXI.

DOI

Scopus

5

被引用数

(Scopus)
High sensitivity all sky X-ray monitor and survey with MAXI

N. Isobe, T. Mihara, M. Kohama, M. Suzuki, M. Matsuoka, S. Ueno, H. Tomida, N. Kawai, J. Kataoka, A. Yoshida, K. Yamaoka, H. Tsunemi, E. Miyata, H. Negoro, M. Nakajima, M. Morii

AIP Conference Proceedings 921 440 - 441 2007年

　概要を見る

MAXI is an all sky X-ray monitor to be mounted on the Japanese Experimental Module in the International Space Station (ISS). It scans almost all over the sky every 96 minutes, in the course of the orbital motion of the ISS. MAXI is designed to have a sensitivity, significantly higher than the previous X-ray monitors, and then, to detect X-ray sources as faint as 1 mCrab in a week observation. Therefore, MAXI is expected to create a novel catalogue of not only the stable X-ray sources but also the highly variable ones in the sky, especially active galactic nuclei for the first time. If MAXI detects X-ray phenomena, alerts will be quickly made through the Internet. © 2007 American Institute of Physics.

DOI

Scopus
Suzaku observations of AGN and synergy with GLAST

Jun Kataoka, Tad Takahashi, Greg Madejski

AIP Conference Proceedings 921 89 - 91 2007年

　概要を見る

In next five years, dramatic progress is anticipated for the AGN studies, as we have two important missions to observe celestial sources in the high energy regime: GLAST and Suzaku. Suzaku is the 5th Japanese X-ray astronomy satellite which was successfully launched in July 2005. It carries four X-ray sensitive imaging CCD cameras (0.2-12 keV) located in the focal planes of X-ray telescope, and a non-imaging, collimated hard X-ray detector, which extends the bandpass of the observatory to include the 10-600 keV range. Simultaneous monitoring observations by the two instruments (GLAST and Suzaku) will be particularly valuable for variable radio-loud AGN, allowing the cross-correlations of time series as well as detailed modeling of the spectral evolution between the X-ray and gamma-ray energy bands. In this paper, we show early highlights from Suzaku observations of radio-loud AGNs, and discuss what we can do with GLAST in forthcoming years. © 2007 American Institute of Physics.

DOI

Scopus
Direct and reprocessed gamma-ray emission of kpc-scale jets in FR I radio galaxies

L. Stawarz, T. M. Kneiske, J. Kataoka

FIRST GLAST SYMPOSIUM 921 363 - + 2007年 [査読有り]

　概要を見る

We discuss the contribution of kiloparsec-scale jets in FR I radio galaxies to the diffuse gamma-ray background radiation. The analyzed gamma-ray emission comes from inverse-Compton scattering of starlight photon fields by the ultrarelativistic electrons whose synchrotron radiation is detected from such sources at radio, optical and X-ray energies. We find that these objects, under the minimum-power hypothesis (corresponding to a magnetic field of 300 mu G in the brightest knots of these jets), can contribute about one percent to the extragalactic gamma-ray background measured by EGRET. We point out that this result already indicates that the magnetic fields in kpc-scale jets of low-power radio galaxies are not likely to be smaller than 10 mu G on average, as otherwise the extragalactic gamma-ray background would be overproduced.

DOI

Scopus
High sensitivity balloon-borne hard X-ray/soft gamma-ray polarimeter PoGOLite

T. Mizuno, M. Arimoto, M. Axelsson, C. -I. Bjornsson, G. Bogaert, P. Carlson, W. Craig, Y. Fukazawa, S. Gunji, L. Hjalmarsdotter, T. Kamae, Y. Kanai, J. Kataoka, J. Katsuta, N. Kawai, M. Kiss, W. Klamra, S. Larsson, G. Madejski, C. Marini Bettolo, J. Ng M. Pearce, F. Ryde, H. Tajima, H. Takahashi, T. Tanaka, T. Thurston, M. Ueno, G. Varner, H. Yoshida

2007 IEEE NUCLEAR SCIENCE SYMPOSIUM CONFERENCE RECORD, VOLS 1-11 4 2538 - + 2007年

　概要を見る

The Polarized Gamma-ray Observer - Lightweight Version (PoGOLite) is a new balloon experiment capable of detecting 10% polarization from a 200 mCrab source in the 25-80 keV energy range in a single 6-hour flight for the first time. Polarization measurements of hard X-rays and soft gamma-rays are expected to provide a powerful probe into high-energy emission mechanisms as well as source geometries. PoGOLite uses Compton scattering and photo-absorption to measure polarization in an array of 217 well-type phoswich detector cells made of plastic and BGO scintillators. The adoption of a well-type phoswich counter concept and a thick polyethylene neutron shield provides a narrow field-of-view (1.25 msr), a large effective area ( >= 250 cm(2) at 40-50 keV), a high modulation factor (more than 25 %) and the low background (- 100 mCrab) required to conduct high-sensitivity polarization measurements. Through tests in laboratories and accelerator facilities of a scaled-down prototype with the front-end electronics of flight design and an extensive study by Monte-Carlo simulation, we have demonstrated high instrument performance. PoGOLite Will be ready for a first engineering flight in 2009 and a science flight in 2010, during which polarization signals from the Crab Nebula/pulsar, Cygnus X-1 and other objects will be observed.

DOI

Scopus

1

被引用数

(Scopus)
Data acquisition system for the PoGOLite astronomical hard X-ray polarimeter

T. Tanaka, M. Arimoto, M. Axelsson, C. -I. Bjornsson, G. Bogaert, P. Carlson, M. Cooney, W. Craig, O. Engdegard, Y. Fukazawa, S. Gunji, L. Hjalmarsdotter, T. Kamae, Y. Kanai, J. Kataoka, J. Katsuta, N. Kawai, J. Kazejev, M. Kiss, W. Klamra, S. Larsson, G. Madejski, C. Marini Bettolo, T. Mizuno, J. Ng, M. Nomachi, H. Odaka, M. Pearce, L. Ruckman, F. Ryde, H. Tajima, H. Takahashi, T. Takahashi, T. Thurston, M. Ueno, G. Varner, T. Ylinen, H. Yoshida, T. Yuasa

2007 IEEE NUCLEAR SCIENCE SYMPOSIUM CONFERENCE RECORD, VOLS 1-11 1 445 - 449 2007年

　概要を見る

The PoGOLite is a new balloon-borne instrument to measure the polarization of hard X-rays/soft gamma-rays in the 25-80 keV energy range for the first time. In order to detect the polarization, PoGOLite measures the azimuthal angle asymmetry of Compton scattering and the subsequent photo-absorption in an array of detectors. This array consists of 217 well-type phoswich detector cells (PDCs) surrounded by a side anti-coincidence shield (SAS) composed of 54 segments of BGO crystals. At balloon altitude, the intensity of backgrounds due to cosmic-ray charged particles, atmospheric gamma-rays and neutrons is extremely high, typically a few hundred Hz per unit. Hence the data acquisition (DAQ) system of PoGOLite is required to handle more than 270 signals simultaneously, and detect weak signals from astrophysical objects (100mCrab, 1.5 cs(-1) in 25-80 keV) under such a severe environment. We have developed a new DAQ system consisting of front-end electronics, waveform digitizer, Field Programmable Gate Array (FPGA) and a microprocessor. In this system, all output signals of PDC / SAS are fed into individual charge-sensitive amplifier and then digitized to 12 bit accuracy at 24 MSa/s by pipelined analog to digital converters. A DAQ board for the PDC records waveforms which will be examined in an off-line analysis to distinguish signals from the background events and measure the energy spectrum and polarization of targets. A board for the SAS records hit pattern to be used for background rejection. It also continuously records a pulse-height analysis (PHA) histogram to monitor incident background flux. These basic functions of the DAQ system were verified in a series of beam tests.

DOI

Scopus

3

被引用数

(Scopus)
Reverse-type avalanche photodiode for scintillation detection and intrinsic energy resolution of BGO and GSO : Ce

Sato Mitsuhiro, Yanagida Takayuki, Yoshikawa Akira, Yatsu Yousuke, Kataoka Jun, Ishikawa Yoshitaka, Saito Fumio, IEEE

2007 Ieee Nuclear Science Symposium Conference Record, Vols 1-11 2023 - 2032 2007年 [査読有り]
Suzaku observation of TeV SNR RX J1713.7-3946

Takahashi T, Tanaka T, Uchiyama Y, Hiraga J.S, Nakazawa K, Watanabe S, Bamba A, Hughes J.P, Katagiri H, Kataoka J, Kokubun M, Koyama K, Mori K, Petre R, Takahashi H, Tsuboi Y

Progress of Theoretical Physics Supplement ( 169 ) 157 - 161 2007年 [査読有り]

DOI

Scopus
Wide Range Multifrequency Observations of Northern TeV Blazars

Rugamer

Astronomische Nachrichten 328 623 2007年
The X-ray observatory Suzaku

Kazuhisa Mitsuda, Mark Bautz, Hajime Inoue, Richard L. Kelley, Katsuji Koyama, Hideyo Kunieda, Kazuo Makshima, Yoshiaki Ogawara, Robert Petre, Tadayuki Takahashi, Hiroshi Tsunemi, Nicholas E. White, Naohisa Anabuki, Lorella Angelini, Keith Arnaud, Hisamitsu Awaki, Aya Bamba, Kevin Boyce, Gregory V. Brown, Kai-Wing Chan, Jean Cottam, Tadayasu Dotanli, John Doty, Ken Ebisawa, Yuichiro Ezoe, Andrew C. Fabian, Enectali Figueroa, Ryuichi Fujimoto, Yasushi Fukazawa, Tae Furusho, Akihiro Furuzawa, Keith Gendreau, Richard E. Griffiths, Yoshito Haba, Kenji Hamaguchi, Ilana Harrus, Gunther Hasinger, Isamu Hatsukade, Kiyoshi Hayashida, Patrick J. Henry, Junko S. Hiraga, Stephen S. Holt, Ann Hornschemeier, John P. Hughes, Una Hwang, Manabu Ishida, Yoshitaka Ishisaki, Naoki Isobe, Masayuki Itoh, Naoko Iyomoto, Steven M. Kahn, Tuneyoshi Kamae, Hideaki Katagiri, Jun Kataoka, Haruyoshi Katayama, Nobuyuki Kawai, Caroline Kilbourne, Kenzo Kinugasa, Steve Kissel, Shunji Kitamoto, Mitsuhiro Kohama, Takayoshi Kohmura, Motohide Kokubun, Taro Kotani, Jun'ichi Kotoku, Aya Kubota, Greg M. Madejski, Yoshitomo Maeda, Fumiyoshi Makino, Alex Markowitz, Chiho Matsumoto, Hironori Matsumoto, Masaru Matsuoka, Kyoko Matsushita, Dan McCammon, Tatehiko Mihara, Kazutami Misaki, Emi Miyata, Tsunefumi Mizuno, Koji Mori, Hideyuki Mori, Mikio Morii, Harvey Moseley, Koji Mukai, Hiroshi Murakami, Toshio Murakami, Richard Mushotzky, Fumiaki Nagase, Masaaki Namiki, Hitoshi Negoro, Kazubiro Nakazawa, John A. Nousek, Takashi Okajima, Yasushi Ogasaka, Takaya Ohashi, Tai Oshima, Naomi Ota, Masanobu Ozaki, Hideki Ozawa, Arvind N. Parmar, William D. Pence, F. Scott Porter, James N. Reeves, George R. Ricker, Ikuya Sakurai, Wilton T. Sanders, Atsushi Senda, Peter Serlemitsos, Ryo Shibata, Yang Soong, Randall Smith, Motoko Suzuki, Andrew E. Szymkowiak, Hiromitsu Takahashi, Torn Tamagawa, Keisuke Tamura, Takayuki Tamura, Yasuo Tanaka, Makoto Tashiro, Yuzuru Tawara, Yukikatsu Terada, Yuichi Terashima, Hiroshi Tomida, Ken'ichi Torii, Yohko Tsuboi, Masahiro Tsujimoto, Takeshi Go Tsuru, Martin J. L. Turner, Yoshihiro Ueda, Shiro Ueno, Masaru Ueno, Shin'ichiro Uno, Yuji Urata, Shin Watanabe, Norimasa Yamamoto, Kazutaka Yamaoka, Noriko Y. Yamasaki, Koujun Yamashita, Makoto Yamauchi, Shigeo Yamauchi, Tahir Yaqoob, Daisuke Yonetoku, Atsumasa Yoshida

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 S1 - S7 2007年01月 [査読有り]

　概要を見る

High-sensitivity wide-band X-ray spectroscopy is the key feature of the Suzaku X-ray observatory, launched on 2005 July 10. This paper summarizes the spacecraft, in-orbit performance, operations, and data processing that are related to observations. The scientific instruments, the high-throughput X-ray telescopes, X-ray CCD cameras, non-imaging hard X-ray detector are also described.

DOI
Suzaku observations of HESS J1616-508: Evidence for a dark particle accelerator

Hironori Matsumoto, Masaru Ueno, Aya Bamba, Yoshiaki Hyodo, Hideyuki Mori, Hideki Uchiyama, Takeshi Go Tsuru, Katsuji Koyama, Jun Kataoka, Hideaki Katagiri, Tadayuki Takahashi, Junko Hiraga, Shigeo Yamauchi, John P. Hughes, Atsushi Senda, Motohide Kokubun, Takayoshi Kohmura, Frederick S. Porter

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 S199 - S208 2007年01月 [査読有り]

　概要を見る

We observed the bright unidentified TeV gamma-ray source HESS J1616-508 with the X-ray Imaging Spectrometers onboard the Suzaku satellite. No X-ray counterpart was found to a limiting flux of 3.1 x 10(-13) erg s(-1) cm(-2) in the 2-10 keV band, which is some 60-times below the gamma-ray flux in the 1-10 TeV band. This object is bright in TeV gamma-rays, but very dim in the X-ray band, and thus is one of the best examples in the Galaxy of a "dark particle accelerator." We also detected soft thermal emission with kT similar to 0.3-0.6 keV near the location of HESS J1616-508. This may be due to a dust-grain scattering halo from the nearby bright supernova remnant RCW 103.

DOI
Iron and nickel line diagnostics for the Galactic Center diffuse emission

Katsuji Koyama, Yoshiaki Hyodo, Tatsuya Inui, Hiroshi Nakajima, Hironori Matsumoto, Takeshi Go Tsuru, Tadayuki Takahashi, Yoshitomo Maeda, Noriko Y. Yamazaki, Hiroshi Murakami, Shigeo Yamauchi, Yohko Tsuboi, Atsushi Senda, Jun Kataoka, Hiromitsu Takahashi, Stephen S. Holt, Gregory V. Brown

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 ( 1 SPEC. ISS. ) S245 - S255 2007年01月 [査読有り]

　概要を見る

We have observed the diffuse X-ray emission from the Galactic Center (GC) using the X-ray Imaging Spectrometer (XIS) on Suzaku. The high-energy resolution and the low-background orbit provided excellent spectra of the GC diffuse X-rays (GCDX). The XIS found many emission lines in the GCDX near the energy of K-shell transitions of iron and nickel. The most pronounced features are Fe I K alpha at 6.4 keV and K-shell absorption edge at 7.1 keV, which are from neutral and/or low ionization states of iron, and the K-shell lines at 6.7 keV and 6.9 keV from He-like (Fe XXV K alpha) and hydrogenic (Fe XXVI Ly alpha) ions of iron. In addition, K alpha lines from neutral or low ionization nickel (Ni I K alpha) and He-like nickel (Ni XXVII K alpha), Fe I K beta, Fe XXV K beta, Fe XXVI Ly beta, Fe XXV K gamma, and Fe XXVI Ly gamma were detected for the first time. The line center energies and widths of Fe XXV K alpha and Fe XXVI Ly alpha favor a collisional excitation plasma for the origin of the GCDX. The electron temperature determined from the line flux ratio of Fe XXV K alpha/Fe XXV K beta is similar to the ionization temperature determined from that of Fe XXV K alpha/Fe XXVI Ly alpha. Thus it would appear that the GCDX plasma is close to ionization equilibrium. The 6.7 keV flux and temperature distribution to the galactic longitude is smooth and monotonic, in contrast to the integrated point source flux distribution. These facts support the hypothesis that the GCDX is truly diffuse emission rather than the integration of the outputs of a large number of unresolved point sources. In addition, our results demonstrate that the chemical composition of Fe in the interstellar gas near the GC is constrained to be about 3.5 times solar abundance.

DOI
Hard X-ray Detector (HXD) on board Suzaku

Tadayuki Takahashi, Keiichi Abe, Manabu Endo, Yasuhiko Endo, Yuuichiro Ezoe, Yasushi Fukazawa, Masahito Hamaya, Shinya Hirakuri, Soojing Hong, Michihiro Horii, Hokuto Inoue, Naoki Isobe, Takeshi Itoh, Naoko Iyomoto, Tuneyoshi Kamae, Daisuke Kasama, Jun Kataoka, Hiroshi Kato, Madoka Kawaharada, Naomi Kawano, Kengo Kawashima, Satoshi Kawasoe, Tetsuichi Kishishita, Takao Kitaguch, Yoshihito Kobayashi, Motohide Kokubun, Jun'ichi Kotoku, Manabu Kouda, Aya Kubota, Yoshikatsu Kuroda, Greg Madejski, Kazuo Makishima, Kazunori Masukama, Yukari Matsumoto, Takefumi Mitani, Ryohei Miyawaki, Tsunefumi Mizuno, Kunishiro Mori, Masanori Mori, Mio Murashima, Toshio Murakami, Kazuhiro Nakazawa, Hisako Niko, Masaharu Nomachi, Yuu Okada, Masanori Ohno, Kousuke Oonuki, Naomi Ota, Hideki Ozawa, Goro Sato, Shingo Shinoda, Masahiko Sugiho, Masaya Suzuki, Koji Taguchi, Hiromitsu Takahashi, Isao Takahashi, Shin'ichiro Takeda, Ken-ichi Tamura, Takayuki Tamura, Takaaki Tanaka, Chiharu Tanihata, Makoto Tashiro, Yukikatsu Terada, Shin'ya Tominaga, Yasunobu Uchiyama, Shin Watanabe, Kazutaka Yamaoka, Takayuki Yanagida, Daisuke Yonetoku

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 ( 1 SPEC. ISS. ) S35 - S51 2007年01月 [査読有り]

　概要を見る

The Hard X-ray Detector (HXD) on board Suzaku covers a wide energy range from 10 keV to 600 keV by the combination of silicon PIN diodes and GSO scintillators. The HXD is designed to achieve an extremely low in-orbit background based on a combination of new techniques, including the concept of a well-type active shield counter. With an effective area of 142 cm(2) at 20 keV and 273 cm(2) at 150 keV, the background level at sea level reached similar to 1 X 10(-5) cts s(-1) cm(-2) keV(-1) at 30 keV for the PIN diodes, and similar to 2 X 10(-5) cts s(-1) cm(-2) keV(-1) at 100 keV, and similar to 7 X 10(-6) cts s(-1) cm(-2) keV(-1) at 200 keV for the phoswich counter. Tight active shielding of the HXD results in a large array of guard counters surrounding the main detector parts. These anti-coincidence counters, made of similar to 4 cm thick BGO crystals, have a large effective area for sub-MeV to MeV gamma-rays. They work as an excellent gamma-ray burst monitor with limited angular resolution (similar to 5 degrees). The on-board signal-processing system and the data transmitted to the ground are also described.

DOI
A Suzaku observation of the low-ionization Fe-Line emission from RCW 86

Masaru Ueno, Rie Sato, Jun Kataoka, Aya Bamba, Ilana Harrus, Junko Hiraga, John P. Hughes, Caroline A. Kilbourne, Katsuji Koyama, Motohide Kokubun, Hiroshi Nakajima, Masanobu Ozaki, Robert Petre, Tadayuki Takahashi, Takaaki Tanaka, Hiroshi Tomida, Hiroya Yaniaguchi

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 S171 - S176 2007年01月 [査読有り]

　概要を見る

The newly operational X-ray satellite Suzaku observed the southwestern quadrant of the supernova remnant RCW 86 in 2006 February to study the nature of the 6.4 keV emission line first detected with the Advanced Satellite for Cosmology and Astronomy (ASCA). The new data confirm the existence of the line, localizing it for the first time; most of the line emission is adjacent and interior to the forward shock, and not at the locus of the continuum hard emission. We also report the first detection of a 7.1 keV line, which we interpret as K beta emission from low-ionization iron. The Fe K line features are consistent with a non-equilibrium plasma of Fe-rich ejecta with n(e)t less than or similar to 10(9) cm(-3) s and kT(e) similar to 5 keV. This combination of low n(e)t and high kT(e) suggests collisionless electron heating in an SNR shock. The Fe K alpha line shows evidence for intrinsic broadening, with a width of 47 (34-59) eV (99% error region). The difference in the spatial distributions of the hard continuum above 3 keV and the Fe K line emission supports a synchrotron origin for the hard continuum.

DOI
Pre-flight performance and radiation hardness of the Tokyo Tech pico-satellite Cute-1.7

J. Kotoku, J. Kataoka, Y. Kuramoto, Y. Tsubuku, Y. Yatsu, R. Sato, T. Ikagawa, T. Saito, N. Kawai, K. Konoue, N. Miyashita, M. Iai, K. Omagari, M. Kashiwa, H. Yabe, K. Imai, Miyamoto, K. Fujiwara, S. Masumoto, T. Usuda, T. Iljic, A. Konda, S. Sugita, T. Yamanaka, D. Matsuura, T. Sagami, S. Kajiwara, Y. Funaki, S. Matsunaga, T. Shima, S. Kishimoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 565 ( 2 ) 677 - 685 2006年09月 [査読有り]

　概要を見る

The Cute-1.7 was launched successfully in February 2006 as a piggyback satellite of the Astro-F mission. The Cute-1.7 dimensions are 10 x 10 x 20 cm(3) box with a total mass of 3.6kg. It is the second pico-satellite to have been developed completely by students of the Tokyo Institute of Technology (Tokyo Tech.) after the successful launch of the CUTE-I in June 2003. The goals of the Cute-1.7 mission are two-fold: (1) to validate high-performance, commercially available products for the first time in space. We particularly use personal digital assistants (PDAs) as a main computer in orbit (2) to demonstrate new potential uses for small satellites in various space studies, as proposed by the "satellite-core" concept. For the Cute-1.7 mission, we will carry avalanche photo diodes (APDs) as a high-count particle monitor in low-Earth orbit. Here we present details of various ground tests and pre-flight performance of the Cute-1.7 immediately before the launch. Results of the Cute-1.7 mission will provide quick feedback for space applications of APDs in Japan's future X-ray astronomy mission NeXT. (c) 2006 Elsevier B.V. All rights reserved.

DOI

Scopus

6

被引用数

(Scopus)
Study of avalanche photodiodes for soft X-ray detection below 20 keV

Y. Yatsu, Y. Kuramoto, J. Kataoka, J. Kotoku, T. Saito, T. Ikagawa, R. Sato, N. Kawai, S. Kishimoto, K. Mori, T. Kamae, Y. Ishikawa, N. Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 564 ( 1 ) 134 - 143 2006年08月 [査読有り]

　概要を見る

The performance of the large area reach-through avalanche photodiode (APD), manufactured by Hamamatsu Photonics, K.K. as a high resolution X-ray detector is presented. The mentioned APD has an area of 3 mm 0, a fast time response for signal carrier collection and its thick depletion layer of 130 pm shows a potential to be used as an effective X-ray absorber below 20 keV. Having a capacitance of similar to 10 pF and a low dark current of 5 nA for a gain of 15, at room temperature, this APD had demonstrated one of the best energy resolutions within this kind of devices: 6.4% (FWHM) for 5.9 keV photons with a minimum detectable energy of 0.3 keV, measured at -20 degrees C. The experiments for the timing property were made in a synchrotron beam facility using an 8 keV X-ray beam; the reached count rate was above 108 counts/s, corresponding to a very short dead time of 4.5 ns/pulse. In order to test the radiation hardness of the APD, the device was irradiated at a Ring Cyclotron Facility with a 53.5 MeV proton beam. The total dose was of 11.3 krad and no fatal damage was found in the APD, although the dark current of the APD had shown an increase of one order of magnitude. Finally, the obtained results allow us to affirm that the reach-through APD has the potential to become an excellent X-ray detector, especially in the space mission application. (c) 2006 Elsevier B.V. All rights reserved.

DOI

Scopus

37

被引用数

(Scopus)
Dynamics and high-energy emission of the flaring HST-1 knot in the M 87 jet

L. Stawarz, F. Aharonian, J. Kataoka, M. Ostrowski, A. Siemiginowska, M. Sikora

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 370 ( 2 ) 981 - 992 2006年08月 [査読有り]

　概要を見る

Stimulated by recent observations of a giant radio-to-X-ray synchrotron flare from Hubble Space Telescope (HST)-1, the innermost knot of the M 87 jet, as well as by the detection of a very high energy gamma-ray emission from M 87, we investigated the dynamics and multiwavelength emission of the HST-1 region. We study thermal pressure of the hot interstellar medium in M 87 and argue for the presence of a gaseous condensation in its central parts. We postulate that this additional feature is linked to the observed central stellar cusp of the elliptical host. Interaction of the jet with such a feature is likely to result in the formation of a stationary converging/diverging reconfinement/reflected shock structure in the innermost parts of the M 87 jet. We show that for a realistic set of the outflow parameters, a stationary and a flaring part of the HST-1 knot located similar to 100 pc away from the active centre can be associated with the decelerated portion of the jet matter placed immediately downstream of the point where the reconfinement shock reaches the jet axis. We discuss a possible scenario explaining a broad-band brightening of the HST-1 region related to the variable activity of the central core. In particular, we show that assuming a previous epoch of the high central black hole activity resulting in ejection of excess particles and photons down along the jet, one may first expect a high-energy flare of HST-1 due to inverse-Comptonization of the nuclear radiation, followed after a few years by an increase in the synchrotron continuum of this region. The synchrotron flare itself could be accompanied by a subsequent inverse-Compton brightening due to upscattering of the ambient (mostly starlight) photons. If this is the case, then the recently observed order-of-magnitude increase in the knot luminosity in all spectral bands could be regarded as an unusual echo of the order-of-magnitude outburst that had happened previously (and could be eventually observed some similar to 40 yr ago) in the highly relativistic active core of the M 87 radio galaxy. We show that very high energy gamma-ray fluxes expected in a framework of the proposed scenario are consistent with the observed ones.

DOI

Scopus

132

被引用数

(Scopus)
An active gain-control system for avalanche photo-diodes under moderate temperature variations

J. Kataoka, R. Sato, T. Ikagawa, J. Kotoku, Y. Kuramoto, Y. Tsubuku, T. Saito, Y. Yatsu, N. Kawai, Y. Ishikawa, N. Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 564 ( 1 ) 300 - 307 2006年08月 [査読有り]

　概要を見る

Avalanche photodiodes (APDs) are a promising light sensor for various fields of experimental physics. It has been argued, however, that variation of APD gain with temperature could be a serious problem preventing APDs from replacing traditional photomultiplier tubes (PMTs) in some applications. Here we develop an active gain-control system to keep the APD gain stable under moderate temperature variations. As a performance demonstration of the proposed system, we have tested the response of a scintillation photon detector consisting of a 5 x 5 mm 2 reverse-type APD optically coupled with a CsI(Tl) crystal. We show that the APD gain was successfully controlled under a temperature variation of Delta T = 20 degrees C, within a time-cycle of 6000 s. The best FWHM energy resolution of 6.1 +/- 0.2 % was obtained for 662 keV gamma-rays, and the energy threshold was as low as 6.5 keV, by integrating data from +20 degrees C-0 degrees C cycles. The corresponding values for -20 degrees C-0 degrees C cycles were 6.9 +/- 0.2% and 5.2 keV, respectively. These results are comparable, or only slightly worse than that obtained at a fixed temperature. Our results suggest new potential uses for APDs in various space researches and nuclear physics. As examples, we briefly introduce the NeXT and Cute-1.7 satellite missions that will carry the APDs as scientific instruments for the first time. (c) 2006 Elsevier B.V. All rights reserved.

DOI

Scopus

24

被引用数

(Scopus)
The spectral energy distribution of PKS 2004-447: a compact steep-spectrum source and possible radio-loud narrow-line Seyfert 1 galaxy

L. C. Gallo, P. G. Edwards, E. Ferrero, J. Kataoka, D. R. Lewis, S. P. Ellingsen, Z. Misanovic, W. F. Welsh, M. Whiting, Th. Boller, W. Brinkmann, J. Greenhill, A. Oshlack

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 370 ( 1 ) 245 - 254 2006年07月 [査読有り]

　概要を見る

An investigation of the spectral energy distribution ( SED) of the compact steep-spectrum (CSS) source and possible radio-loud narrow-line Seyfert 1 galaxy (NLS1), PKS 2004-447, is presented. Five out of six well-studied radio-loud NLS1 share this dual classification [optically defined as an NLS1 with radio definition of a CSS or gigahertz-peaked spectrum (GPS) source], suggesting that the connection could have a physical origin. The SED is created from simultaneous observations (within 24 h) at radio (from Australia Telescope Compact Array), optical/near-infrared (NIR) (from Siding Spring) and UV/X-ray (from XMM-Newton) wave-lengths. The X-ray data show evidence of short-term variability (primarily a similar to 30 per cent increase in the final 4 ks of the observation), a possible soft excess and negligible absorption. Together with the rest of the SED, the X-ray emission is excessive in comparison to synchrotron plus synchrotron self-Compton (SSC) models. The SED can be described with a two-component model consisting of extended synchrotron/SSC emission with Comptonization in the X-rays, though SSC models with a very high electron-to-magnetic energy density ratio cannot be excluded either. The peak emission in the SED appears to be in the NIR, which can be attributed to thermal emission (T approximate to 1000 K) from a dusty torus. Analysis of a. non-contemporaneous, low-resolution optical spectrum suggests that the narrow-line region (NLR) is much more reddened than the X-ray emitting region suggesting that the gas-to-dust ratio in PKS 2004-447 may be very different than in our own Galaxy. This could be achieved if the radio jets in PKS 2004-447 deposits material from the nucleus into the NLR. Long-term radio monitoring of PKS 2004-447 shows a rather constant light curve over nearly a six-month period with the exception of one outburst when the 6.65-GHz flux increased by similar to 35 per cent over 19 d. It is not possible to differentiate between intrinsic or extrinsic (i.e. interstellar scintillation) origins for this outburst, but the detection of the rare event demonstrates the importance of intensive monitoring campaigns. In comparison to general samples of GPS sources, which appear to be X-ray weak, NLS1-CSS/GPS sources possess stronger X-ray emission relative to radio ( comparable to normal radio-loud AGN). In addition, NLS1-CSS/GPS sources also exhibit lower intrinsic absorption than GPS sources of similar X-ray luminosity. This is consistent with the additional X-ray component required for PKS 2004-447, but larger samples of NLS1-CSS/GPS are needed before any conclusive remarks can be made.

DOI

Scopus

64

被引用数

(Scopus)
The X-ray jet in Centaurus A: Clues to the jet structure and particle acceleration

J Kataoka, L Stawarz, F Aharonian, F Takahara, M Ostrowski, PG Edwards

ASTROPHYSICAL JOURNAL 641 ( 1 ) 158 - 168 2006年04月 [査読有り]

　概要を見る

We report detailed studies of the X-ray emission from the kiloparsec-scale jet in the nearest active galaxy, Centaurus A. By analyzing the highest quality X-ray data obtained with the Chandra ACIS-S, 41 compact sources (mostly bright jet knots) were found within the jet on angular scales less than 400, 13 of which were newly identified. We construct the luminosity function for the detected jet knots and argue that the remaining emission is most likely to be truly diffuse, rather than resulting from the sum of many unresolved fainter knots. We subtracted the contributions of the bright knots from the total X-ray jet flux, and show that the remaining extended emission has a relatively flat-topped intensity profile in the transverse jet direction, with the intensity peaking at the jet boundaries between 5000 and 17000. We note that limb-brightened morphologies have been observed previously at radio frequencies in a few FR I and FR II jet sources, but never so clearly at higher photon energies. Our result therefore supports a stratified jet model, consisting of a relativistic outflow including a boundary layer with a velocity shear. In addition, we found that the X-ray spectrum of the diffuse component is almost uniform across and along the jet, with an X-ray energy spectral index of alpha(X)approximate to 1, similar to those observed in the compact knots. We discuss this spectral behavior within a framework of shock and stochastic particle acceleration processes, connected with the turbulent, supersonic, and nonsteady nature of the relativistic outflow. We note some evidence for a possible spectral hardening at the outer sheath of the jet, and manifesting itself in observed X-ray spectra of alpha(X)< 0.5 in the most extreme cases. Due to the limited photon statistics of the present data, further deep observations of Centaurus A are required to determine the reality of this finding; however, we note that the existence of the hard X-ray features at outer jet boundaries would provide an important challenge to theories for the evolution of ultrarelativistic particles within extragalactic jets.

DOI

Scopus

45

被引用数

(Scopus)
The parsec-scale jet of PKS 0637-752

Philip G. Edwards, B. Glenn Piner, Steven J. Tingay, James E. J. Lovell, Jun Kataoka, Roopesh Ojha, Yasuhiro Murata

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 58 ( 2 ) 233 - 241 2006年04月 [査読有り]

　概要を見る

Chandra observations of the quasar PKS 0637-752 during its checkout phase resulted in the unexpected detection of a luminous kiloparsec-scale X-ray jet. The apparent superluminal speed of this jet on the parsec-scale, based on two VSOP and four ground-based observations, has proven crucial to understanding the X-ray production in the arcsec-scale jet. We present here for the first time the full details of the ground-based observations used to determine the parsec-scale jet speed, describe the results of a third VSOP observation, and examine the reported jet speed in the light of more recent ground-based VLBI observations. We find some evidence of increased source activity coincident with extrapolated epochs of jet component ejection, although the monitoring of the source is relatively sparse and the ejection epochs are not tightly constrained. We also construct the spectral energy distribution for the nucleus of PKS 0637-752 and show that it can be modelled well in terms of a one-zone synchrotron self-Compton model of an electron-positron jet with a Doppler factor of similar to 10, consistent with the results of the VLBI observations.

DOI

Scopus

9

被引用数

(Scopus)
Kiloparsec-scale jets in FR I radio galaxies and the gamma-ray background

L Stawarz, TM Kneiske, J Kataoka

ASTROPHYSICAL JOURNAL 637 ( 2 ) 693 - 698 2006年02月 [査読有り]

　概要を見る

We discuss the contribution of kiloparsec- scale jets in FR I radio galaxies to the diffuse gamma- ray background radiation. The analyzed gamma- ray emission comes from inverse- Compton scattering of starlight photon fields by the ultrarelativistic electrons whose synchrotron radiation is detected from such sources at radio, optical, and X- ray energies. We find that these objects, under the minimum- power hypothesis ( corresponding to a magnetic field of 300 mu G in the brightest knots of these jets), can contribute about one percent to the extragalactic gamma- ray background measured by EGRET. We point out that this result already indicates that the magnetic fields in kiloparsec- scale jets of low- power radio galaxies are not likely to be smaller than 10 mu G on average, as otherwise the extragalactic gamma- ray background would be overproduced.

DOI

Scopus

34

被引用数

(Scopus)
Hard X-ray Imager for the NeXT Mission

Kazuhiro Nakazawa, Yasushi Fukazawa, Tuneyoshi Kamae, Jun Kataoka, Motohide Kokubun, Kazuo Makishima, Tsunefumi Mizuno, Toshio Murakami, Masaharu Nomachi, Hiroyasu Tajima, Tadayuki Takahashi, Makoto Tashiro, Toru Tamagawa, Yukikatsu Terada, Shin Watanabe, Kazutaka Yamaoka, Daisuke Yonetoku

SPACE TELESCOPES AND INSTRUMENTATION II: ULTRAVIOLET TO GAMMA RAY, PTS 1 AND 2 6266 2006年 [査読有り]

　概要を見る

The hard X-ray imager (HXI) is the primary detector of the NeXT mission, proposed to explore high-energy non-thermal phenomena in the universe. Combined with a novel hard X-ray mirror optics, the HXI is designed to provide better than arc-minutes imaging capability with 1 keV level spectroscopy, and more than 30 times higher sensitivity compared with any existing hard X-ray instruments. The base-line design of the HXI is improving to secure high sensitivity. The key is to reduce the detector background as far as possible. Based on the experience of the Suzaku satellite launched in July 2005, the current design has a well-type tight active shield and multi layered, multi material imaging detector made of Si and CdTe. Technology has been under development for a few years so that we have reached the level where a basic detector performance is satisfied. Design tuning to further improve the sensitivity and reliability is on-going.

DOI

Scopus

15

被引用数

(Scopus)
Chandra observation of RCW 89 at two epochs

Y. Yatsu, N. Kawai, J. Kataoka, T. Tamura, W. Brinkmann

European Space Agency, (Special Publication) ESA SP 1 ( 604 ) 379 - 380 2006年

　概要を見る

We presented a Chandra observation of the HII region RCW 89 in Dec 2004. RCW 89 is part of the radio shell supernova remnant MSH 15-52 which contains a 150 ms young pulsar PSR B1509-58. Comparing with the X-ray image taken by Chandra in Aug 2000, we found that each plasma clouds in RCW 89 have moved outward from the SNR center. The velocity of the radial motion is 5800 ± 2300 km s-1. This result agrees with the scenario in which the plasma clouds in RCW 89 are the SN ejecta from the progenitor of the pulsar.
Development of the collimator response of gas slit camera of MAXI

Mikio Morii, Masaru Matsuoka, Shiro Ueno, Hiroshi Tomida, Haruyoshi Katayama, Kazuyoshi Kawasaki, Takao Yokota, Naoyuki Kuramata, Tatehiro Mihara, Mitsuhiro Kohama, Naoki Isobe, Motoki Nakajima, Hiroshi Tsunemi, Emi Miyata, Atsumasa Yoshida, Kazutaka Yamaoka, Yuichiro Tsuchiya, Takehiro Miyakawa, Nobuyuki Kawai, Jun Kataoka, Satoshi Tanaka, Hitoshi Negoro

Proceedings of SPIE - The International Society for Optical Engineering 6266 II 2006年

　概要を見る

Monitor of All-sky X-ray Image (MAXI) is an X-ray all-sky scanner, which will be attached on Exposed Facility of Japanese Experiment Module dubbed "Kibo" of International Space Station (ISS). MAXI will be launched by the Space Shuttle or the Japanese H-IIA Transfer Vehicle (HTV) in 2008. MAXI carries two types of X-ray cameras: Solid-state Slit Camera (SSC) for 0.5 - 10 keV and Gas Slit Camera (GSC) for 2-30 keV bands. Both have long narrow fields of view (FOV) made by a slit and orthogonally arranged collimator plates (slats). The FOV will sweep almost the whole sky once every 96 minutes by utilizing the orbital motion of ISS. Then the light curve of an X-ray point source become triangular shape in one transit. In this paper, we present the actual triangular response of the GSC collimator, obtained by our calibration. In fact they are deformed by gaps between the slats, leaning angle of the slats, and the effective width of the slats. We are measuring these sizes by shooting X-ray beams into the detector behind the collimator. We summarize the calibration and present the first compilation of the data to make the GSC collimator response, which will be useful for public users.

DOI

Scopus

4

被引用数

(Scopus)
X-ray emission properties of large scale jets, hotspots and lobes in active galactic nuclei

J Kataoka, L Stawarz

PROCEEDINGS OF THE X-RAY UNIVERSE 2005, VOLS 1 AND 2 604 ( 604 ) 633 - + 2006年 [査読有り]

　概要を見る

We examine a systematic comparison of jet-knots, hotspots and radio lobes recently observed with Chandra and ASCA. The data was compiled at radio (5 GHz) and X-ray frequencies (1 keV) for more than 40 radio galaxies. We examined three models for the X-ray production: synchrotron (SYN), synchrotron self-Compton (SSC) and external Compton on CMB photons (EC). For the SYN sources, X-ray photons are produced by ultrarelativistic electrons with energies 10-100 TeV that must be accelerated in situ. For the other objects, a simple formulation of calculating the "expected" SSC or EC fluxes under an equipartition hypothesis is presented. We confirmed that the observed X-ray fluxes are close to the expected ones for non-relativistic emitting plasma velocities in the case of radio lobes and majority of hotspots, whereas considerable fraction of jet-knots is too bright at X-rays to be explained in this way. We concluded, if the inverse-Compton model is the case, the X-ray bright jet-knots are most likely far from the minimum-power condition. We however prefer the other possibility, namely that the observed X-ray emission from all of the jet-knots is synchrotron in origin.
超小型衛星Cute1.7+APD 搭載のAPD センサー技術

片岡淳

OplusE 特集 ~宇宙における光学~ 10月号 ( vol.28 ) 1037 2006年
Suzaku observations of iron lines and reflection in AGN

J. N. Reeves, A. C. Fabian, J. Kataoka, H. Kunieda, A. Markowitz, G. Miniutti, T. Okajima, P. Serlemitsos, T. Takahashi, Y. Terashima, T. Yaqoob

ASTRONOMISCHE NACHRICHTEN 327 ( 10 ) 1079 - 1086 2006年 [査読有り]

　概要を見る

Initial results on the iron K-shell line and reflection component in several AGN observed as part of the Suzaku Guaranteed Time program are reviewed. This paper discusses a small sample of Compton-thin Seyferts observed to date with Suzaku; namely MCG-5-23-16, MCG-6-30-15, NGC4051, NGC3516, NGC2110, 3C120 and NGC2992. The broad iron K alpha emission line appears to be present in all but one of these Seyfert galaxies, while the narrow core of the line from distant matter is ubiquitous in all the observations. The iron line in MCG-6-30-15 shows the most extreme relativistic blurring of all the objects, the red-wing of the line requires the inner accretion disk to extend inwards to within 2.2R(g) of the black hole, in agreement with the XMM-Newton observations. Strong excess emission in the Hard X-ray Detector (HXD) above 10 keV is observed in many of these Seyfert galaxies, consistent with the presence of a reflection component from reprocessing in Compton-thick matter (e.g. the accretion disk). Only one Seyfert galaxy (NGC 2110) shows neither a broad iron line nor a reflection component. The spectral variability of MCG-6-30-15, MCG-5-23-16 and NGC 4051 is also discussed. In all 3 cases, the spectra appear harder when the source is fainter, while there is little variability of the iron line or reflection component with source flux. This agrees with a simple two component spectral model, whereby the variable emission is the primary power-law, while the iron line and reflection component remain relatively constant. (c) 2006 WILEY-VCH Verlag GmbH&Co. KGaA, Weinheim.

DOI

Scopus

27

被引用数

(Scopus)
Development of 2cm-square Hamamatsu avalanche photodiodes for high-resolution X-rays and gamma-rays detection

R Sato, J Kataoka, Y Kanai, Y Ishikawa, N Kawabata, T Ikagawa, T Saito, Y Kuramoto, N Kawai

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 556 ( 2 ) 535 - 542 2006年01月 [査読有り]

　概要を見る

The avalanche photodiodes (APDs) have attracted considerable attention in various field of experimental physics, but their uses are still limited in only a few experiments, possibly due to their small surface areas. Here, we report the development of the large-area (similar to 20 mm square) APDs, for future applications to high-resolution X-rays and gamma-rays detection. We have made two prototypes of reverse-type APDs based on different concepts, one consists of a 2 x 2 array of 10 x 10 mm(2) pixels (APD1) and the other is a monolithic pixel of 19 x 19mm(2) size (APD2) to achieve a large effective area. By comparing the dark current and gain characteristics at room temperature (+20 degrees C) and lightly cooled environment (-20 degrees C), we quantitatively discussed the origin of predominant noise source at different temperatures. As a performance demonstration of newly developed APDs. we made a scintillation gamma-ray detector consisting of a 20 x 20 x 5mm(3) CsI(Tl) crystal and a 2cm-square APD. The best FWHM energy resolution of 8.5 +/- 0.2% were obtained for 662 keV gamma-rays at room temperature. Similarly, the best FWHM energy resolution of 8.5 0.2% were obtained for 122 keV gamma-rays at lightly cooled environment. We showed that the minimum detectable energy for scintillation light was 15 keV at 20 degrees C and less than 5 keV at -20 degrees C. (c) 2005 Elsevier B.V. All rights reserved.

DOI
Beam test of a prototype phoswich detector assembly for the PoGOLite astronomical soft

Kanai et

Nuclear Instruments and Method section-A 570 61 2006年
HETE-2 localization and observations of the gamma-ray burst GRB 020813

Sato R, Sakamoto T, Kataoka J, Yoshida A, Suzuki M, Kotoku J, Urata Y, Yamamoto Y, Arimoto M, Tamagawa T, Shirasaki Y, Torii K, Matsuoka M, Nakagawa Y, Yamazaki T, Tanaka K, Maetou M, Yamauchi M, Takagishi K, Lamb DQ, Atteia JL, Vanderspek R, Graziani C, Prigozhin G, Villasenor J, Jernigan JG, Crew GB, Hurley K, Ricker GR, Woosley SE, Butler N, Levine A, Doty JP, Donaghy TQ, Fenimore EE, Galassi M, Boer M, Dezalay JP, Olive JF, Braga J, Manchanda R, Pizzichini G, Kawai N

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 57 ( 6 ) 1031 - 1039 2005年12月 [査読有り]

DOI

Scopus

5

被引用数

(Scopus)
Design and development of Tokyo Tech pico-satellite Cute-1.7

Jun'ichi Kotoku, Jun Kataoka, Yusuke Kuramoto, Yoichi Yatsu, Tomoko Ikagawa, Takao Saito, Nobuyuki Kawai, Naoki Miyashita, Masafumi Iai, Kuniyuki Omagari, Ken Fujiwara, Yusuke Funaki, Hideyuki Yabe, Saburo Matunaga, Tatsushi Shima

Proceedings of SPIE - The International Society for Optical Engineering 5898 1 - 10 2005年12月 [査読有り]

　概要を見る

Cute-1.7 is a pico-satellite mainly developed by students at Tokyo Institute of Technology (Tokyo Tech). This will be the second satellite built at Tokyo Tech after the first one, CUTE-I, which was launched in June 2003. The configuration of Cute-1.7 is a 10 cm × 10 cm × 20 cm box with a mass of 2 kg. The engineering objective of Cute-1.7 is to validate commercially available products such as Personal Digital Assistances ( PDAs) in the space environment, and to demonstrate a "satellite core concept" which is dividing a satellite into a bus component and a mission component to adopt various missions. The scientific objective is to demonstrate the performance of avalanche photo diodes (APDs) as future X-ray detectors used in the space environment. Results of this mission will provide the first feedback for a space application of APD such as Japan's future X-ray astronomy mission NeXT.

DOI

Scopus

6

被引用数

(Scopus)
Design and performance of the soft gamma-ray detector for the NeXT mission

H Tajima, T Kamae, G Madejski, Mitani, I, K Nakazawa, T Tanaka, T Takahashi, S Watanabe, Y Fukazawa, T Ikagawa, J Kataoka, M Kokubun, K Makishima, Y Terada, M Nomachi, M Tashiro

IEEE TRANSACTIONS ON NUCLEAR SCIENCE 52 ( 6 ) 2749 - 2757 2005年12月 [査読有り]

　概要を見る

The soft gamma-ray detector (SGD) onboard the Japanese future high energy astrophysics mission (NeXT) is a Compton telescope with narrow field of view, which utilizes Compton kinematics to enhance its background rejection capabilities. It is realized as a hybrid semiconductor gamma-ray detector which consists of silicon and cadmium telluride (CdTe) detectors. It can detect photons in a wide energy band (0.05-1 MeV) at a background level of 5 x 10(-7) counts/s/cm(2) /keV; the silicon layers are required to improve the performance at a lower energy band (< 0.3 MeV). Excellent energy resolution is the key feature of the SGD, allowing it to achieve both high angular resolution and good background rejection capability. An additional capability of the SGD, its ability to measure gamma-ray polarization, opens up a new window to study properties of astronomical objects. We will present the development of key technologies to realize the SGD: high quality CdTe, low noise front-end application-specific integrated circuit, and bump bonding technology. Energy resolutions of 1.7 keV (full-width at half-maximum) for CdTe pixel detectors and 1.1 keV for Si strip detectors have been measured. We also present the validation of Monte Carlo simulation used to evaluate the performance of the SGD.

DOI

Scopus

25

被引用数

(Scopus)
Chandra observation of the interaction between the hot plasma nebula RCW 89 and the pulsar jet of PSR B1509-58

Y Yatsu, N Kawai, J Kataoka, T Kotani, K Tamura, W Brinkmann

ASTROPHYSICAL JOURNAL 631 ( 1 ) 312 - 319 2005年09月 [査読有り]

　概要を見る

We present a Chandra observation of the H (II) region RCW 89. The nebula lies 10' north from the central pulsar PSR B1509-58, and it has been suggested that the nebula is irradiated by the pulsar jet. We performed a spectral analysis of the seven brightest emitting regions aligned in a "horseshoe'' shape and found that the temperature of the knots increases along the horseshoe in the clockwise direction, while, in contrast, the ionization parameter net decreases. This strongly supports a picture of energy transfer via the precessing pulsar jet. We examined the energy budget assuming that RCW 89 is powered by the pulsar jet and confirmed that the pulsar rotational energy loss is sufficient to drive the nebula. The rate of energy injection into RCW 89 by the jet was estimated from the synchrotron radiation flux. We obtained a heating timescale of 1400 yr, which is consistent with the pulsar characteristic age of 1700 yr. To explain the temperature gradient, we discuss the cooling process for plasma clouds in RCW 89. We argue that the plasma clouds can be cooled down by the adiabatic expansion within 70 yr and form the temperature gradient reflecting the sequential heating by the precessing pulsar jet. We also determined the velocities of the individual plasma clouds by spectral fitting. The plasma clouds in RCW 89 are moving away at 240-860 km s(-1), which constrains the inclination angle of the pulsar spin axis i > 50 degrees and the expanding velocity of the shell as nu(shell) > 1100 km s(-1).

DOI

Scopus

17

被引用数

(Scopus)
MITSuME - Multicolor Imaging Telescopes for Survey and Monstrous Explosions

Kotani T, Kawai N, Yanagisawa K, Watanabe J, Arimoto M, Fukushima H, Hattori T, Inata M, Izumiura H, Kataoka J, Koyano H, Kubota K, Kuroda D, Mori J, Nagayama S, Ohta K, Okada T, Okita K, Sato R, Serino Y, Shimizu Y, Shimokawabe T, Suzuki M, Toda H, Ushiyama T, Yatsu Y, Yoshida A, Yoshida M

NUOVO CIMENTO DELLA SOCIETA ITALIANA DI FISICA C-COLLOQUIA ON PHYSICS 28 ( 4-5 ) 755 - 758 2005年07月

DOI
X-ray emission properties of large-scale jets, hot spots, and lobes in active galactic nuclei

J Kataoka, L Stawarz

ASTROPHYSICAL JOURNAL 622 ( 2 ) 797 - 810 2005年04月 [査読有り]

　概要を見る

We examine a systematic comparison of jet knots, hot spots, and radio lobes recently observed with Chandra and ASCA. This report discusses the origin of their X-ray emissions and investigates the dynamics of the jets. The data were compiled at well-sampled radio (5 GHz) and X-ray (1 keV) frequencies for more than 40 radio galaxies. We examine three models for the X-ray production: synchrotron (SYN), synchrotron self-Compton (SSC), and external Compton (EC) on cosmic microwave background (CMB) photons. For the SYN sources-mostly jet knots in nearby low-luminosity radio galaxies-X-ray photons are produced by ultrarelativistic electrons with energies 10 100 TeV that must be accelerated in situ. For the other objects, conservatively classified as SSC or EC sources, a simple formulation of calculating the "expected'' X-ray fluxes under an equipartition hypothesis is presented. We confirm that the observed X-ray fluxes are close to the expected ones for nonrelativistic emitting plasma velocities in the case of radio lobes and the majority of hot spots, whereas a considerable fraction of jet knots are too bright in X-rays to be explained in this way. We examine two possibilities to account for the discrepancy in a framework of the inverse Compton model: ( 1) the magnetic field is much smaller than the equipartition value, and ( 2) the jets are highly relativistic on kiloparsec and megaparsec scales. We conclude that if the inverse Compton model is the case, the X-ray-bright jet knots are most likely far from the minimum-power condition. We also briefly discuss the other possibility, namely, that the observed X-ray emission from all the jet knots is synchrotron in origin.

DOI

Scopus

194

被引用数

(Scopus)
Recent progress of avalanche photodiodes in high-resoution X-rays and gamma-rays detection

J Kataoka, T Saito, Y Kuramoto, T Ikagawa, Y Yatsu, J Kotoku, M Arimoto, N Kawai, Y Ishikawa, N Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 541 ( 1-2 ) 398 - 404 2005年04月 [査読有り]

　概要を見る

We have studied the performance of large area avalanche photodiodes (APDs) recently developed by Hamamatsu Photonics K.K, in high-resolution X-rays and gamma-rays detections. We show that reach-through APD can be an excellent soft X-ray detector operating at room temperature or moderately cooled environment. We obtain the best energy resolution ever achieved with APDs, 6.4% for 5.9 keV X-rays, and obtain the energy threshold as low as 0.5 keV measured at -20 degrees C. Thanks to its fast timing response, signal carriers in the APD device are collected within a short time interval of 1.9 ns (FWHM). This type of APDs can therefore be used as a low-energy, high-counting particle monitor onboard the forthcoming Pico-satellite Cute1.7. As a scintillation photon detector, reverse-type APDs have a good advantage of reducing the dark noise significantly. The best FWHM energy resolutions of 9.4 +/- 0.3% and 4.9 +/- 0.2% were obtained for 59.5 and 662 keV gamma-rays, respectively, as measured with a CsI(T1) crystal. Combination of APDs with various other scintillators (BGO, GSO, and YAP) also showed better results than that obtained with a photomultiplier tube (PMT). These results suggest that APD could be a promising device for replacing traditional PMT usage in some applications. In particular 2-dim, APD array, which we present in this paper, will be a promising device for a wide-band X-ray and x-ray imaging detector in future space research and nuclear medicine. (c) 2005 Elsevier B.V. All rights reserved.

DOI

Scopus

72

被引用数

(Scopus)
Application of CdTe for the NeXT mission

T Takahashi, K Nakazawa, S Watanabe, G Sato, T Mitani, T Tanaka, K Oonuki, K Tamura, H Tajima, T Kamae, G Madejski, M Nomachi, Y Fukazawa, K Makishima, M Kokubun, Y Terada, J Kataoka, M Tashiro

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 541 ( 1-2 ) 332 - 341 2005年04月 [査読有り]

　概要を見る

Cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) have been regarded as promising semiconductor materials for hard X-ray and gamma-ray detection. The high-atomic number of the materials (Z(Cd) = 48, Z(Te) = 52) gives a high quantum efficiency in comparison with Si. The large band-gap energy (E-g = 1.5 eV) allows to operate the detector at room temperature. Based on recent achievements in high-resolution CdTe detectors, in the technology of ASICs and in bump-bonding, we have proposed the novel hard X-ray and gamma-ray detectors for the NeXT mission in Japan. The high-energy response of the super mirror onboard NeXT will enable us to perform the first sensitive imaging observations up to 80keV. The focal plane detector, which combines a fully depleted X-ray CCD and a pixellated CdTe detector, will provide spectra and images in the wide energy range from 0.5 to 80keV. In the soft gamma-ray band up to similar to 1 MeV, a narrow field-of-view Compton gamma-ray telescope utilizing several tens of layers of thin Si or CdTe detector will provide precise spectra with much higher sensitivity than present instruments. The continuum sensitivity will reach several x 10(-8) photons(-1) keV(-1) cm(-1) in the hard X-ray region and a few X 10(-7) photons(-1) keV(-1) cm(-2) in the soft gamma-ray region. (c) 2005 Elsevier B.V. All rights reserved.

DOI
Study of large area Hamamatsu avalanche photodiode in a gamma-ray scintillation detector

T Ikagawa, J Kataoka, Y Yatsu, T Saita, Y Kuramoto, N Kawai, M Kokubun, T Kamae, Y Ishikawa, N Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 538 ( 1-3 ) 640 - 650 2005年02月 [査読有り]

　概要を見る

We have carried out study of a large area (10 x 10 mm(2)), reverse-type avalanche photodiode (APD) recently developed by Hamamatsu photonics. It has low dark current of 3 nA at room temperature, and the gain stability was almost the same as prototypical APDs reported in our previous paper. We studied the performance as a gamma-ray detector with four scintillators, CsI(Tl), BGO, GSO(Ce), and YAP(Ce) crystals. For example we obtained the best energy resolution of 4.9 +/- 0.2 % (FWHM) for 662 keV gamma-rays, as measured with a 10 x 10 x 10 mm 3 CsI(Tl) crystal. The minimum detectable energy was as low as 10 keV at 20degreesC and 3.1 keV at -20degreesC. Thanks to its large effective area, this APD can effectively read out photons from larger size scintillators. When coupling to a 300 x 48 mm(2) BGO plate of 3 mm thickness, an FWHM energy resolution of 20.9 +/- 0.2% was obtained for 662 keV gamma-rays, with the minimum detectable energy of about 60 keV at -15degreesC. These results suggest that our prototype APD can be a promising device for various applications replacing traditional PMTs such as use in space for Japan's future X-ray astronomy mission NeXT. (C) 2004 Elsevier B.V. All rights reserved.

DOI

Scopus

58

被引用数

(Scopus)
大学小型衛星Cute-1.7の開発現状(1)

古徳純一, 倉本祐輔, 片岡淳

宇宙科学シンポジウム 5 384 - 387 2005年01月

CiNii
24pXK-8 学生主導の小型衛星開発 : 大学小型衛星Cuteの開発現状(X線衛星装置開発,宇宙線・宇宙物理)

古徳純一, 片岡淳, 河合誠之, 倉本祐介, 谷津陽一, 五十川知子, 齊藤孝男

日本物理学会講演概要集 60.1.1 90 2005年

DOI CiNii
BGO readout with photodiodes as a soft gamma-ray detector at -30 °C

T. Nakamoto, Y. Fukazawa, T. Ohsugi, T. Kamae, J. Kataoka

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 536 ( 1-2 ) 136 - 145 2005年01月

　概要を見る

BGO is expected to be plausible devices for soft gamma-ray detectors, because of a high detection efficiency for soft gamma-rays. Here we report on the good performance of BGO readout with PIN-photodiode or avalanche photodiode as a soft gamma-ray detector. We confirmed that the signal output of BGO becomes comparable to that of GSO when it is readout with photodiodes due to better matching between emission wavelength of BGO and quantum efficiency of photodiode. The energy resolution of 6.2% and 3.4% for 662 and 1836 keV, respectively, gamma-rays at -30 °C is obtained with the combination of the 5 x 5 x 5mm3 cube BGO and the Hamamatsu avalanche photodiode (APD) S8664-55. In this combination, the lowest detectable energy is found to be ∼ l0keV. These performances are better than that obtained with Photomultiplier tube (PMT), and our results increase many possible applications of BGO readout with photodiodes as soft gamma-ray detectors. © 2004 Elsevier B.V. All rights reserved.

DOI

Scopus

8

被引用数

(Scopus)
MITSuME - Multicolor imaging telescopes for survey and monstrous explosions

T. Kotani, N. Kawai, K. Yanagisawa, J. Watanabe, M. Arimoto, H. Fukushima, T. Hattori, M. Inata, H. Izumiura, J. Kataoka, H. Koyano, K. Kubota, D. Kuroda, M. Mori, S. Nagayama, K. Ohta, T. Okada, K. Okita, R. Sato, Y. Serino, Y. Shimizu, T. Shimokawabe, M. Suzuki, H. Toda, T. Ushiyama, Y. Yatsu, A. Yoshida, M. Yoshida

Nuovo Cimento della Societa Italiana di Fisica C 28 ( 4-5 ) 755 - 758 2005年

　概要を見る

Development of MITSuME is reported. Two 50- cm optical telescopes have been built at Akeno in Yamanashi prefecture and at Okayama Astrophysical Observatory (OAO) in Okayama prefecture. Three CCD cameras for simultaneous g′RcIc photometry are to be mounted on each focal plane, covering a wide FOV of about 30″ × 30″. The limiting magnitude at V is fainter than 18. In addition to these two optical telescopes, a 91-cm IR telescope with a 1° × 1° field of view is being built at OAO, which performs photometry in Y J H K bands. These robotic telescopes can start the observation of counterparts of a GRB within a minute from an alert. We aim to obtain photometric redshifts exceeding 10 with these telescopes. The performance and the current construction status of the telescopes are presented. © Società Italiana di Fisica.
Detection of nonthermal X-ray structures near the galactic center with Chandra

Atsushi Senda, Katsuji Koyama, Ken Ebisawa, Jun Kataoka, Yoshiaki Sofue, Bosch-Ramon, Pietsch

Proceedings of the International Astronomical Union 1 ( S230 ) 24 - 28 2005年

　概要を見る

We have discovered a number of nonthermal X-ray features within central 40 pc region of the Galactic center by analysing 600-ksec observations of Chandra archival data. Most of the detected X-ray structures exhibit small-scale knot-like morphologies and their spectra are well reproduced by single hard power-law with photon indices of 1-2. Among them, the most outstanding features are the three X-ray knots which are aligned on a straight line from the potition of Sgr A* to north-northwest direction. The X-ray properties of these knots lead us to suspect that they are X-ray jets ejected from Sgr A* in the recent past. In addition, we have obtained an indication that the summed flux of nonthermal diffuse X-rays within 30 pc of the GC seems to be smoothly connected to the 20-100 keV flux detected with INTEGRAL IBIS/ISGRI. These results suggest that the origin of GC hard X-rays (or High energy Gamma-rays) is not (or partly) from the Galactic nucleus. © 2006 International Astronomical Union.

DOI

Scopus
Detector response of GSC/MAXI and its expected performance in orbit

Y. Tsuchiya, A. Yoshida, K. Yamaoka, T. Arakuni, T. Miyakawa, M. Matsuoka, S. Ueno, H. Tomida, T. Yokota, K. Kawasaki, N. Kuramata, H. Katayama, M. Morii, T. Mihara, M. Nakajima, N. Isobe, M. Kohama, H. Tsunemi, E. Miyata, N. Kawai, J. Kataoka, H. Negoro

Proceedings of SPIE - The International Society for Optical Engineering 5898 1 - 10 2005年

　概要を見る

Monitor of All-sky X-ray Image(MAXI) is an X-ray all sky monitor, which will be attached to the Japanese Experiment Module (JEM) on the International Space Station (ISS) around the year 2008. MAXI carries two types of scientific instruments. The Gas Slit Camera(GSC) consists of twelve Xe filled one-dimensional position sensitive gas proportional counters sensitive to X-ray in 2-30 keV band. The Solid-state Slit Camera (SSC) is a set of X-ray CCD arrays sensitive to 0.5-10 keV photons. Both detectors are utilized in combination with a slit and orthogonally arranged collimator plates to produce one-dimensional X-ray images along sky great circles. The instruments are now under fabrication and preflight testing. A detector response matrix (DRM) of GSC is also under development phase based on flight model calibration tests for counters and collimators. MAXI's overall performance depends on not only hardware characteristics but on the fact that the field-of-view changes in time even during observations. To study this complicated situation, we are developing a software, DRM builder, and also a simulation software to evaluate "realistic" performance of GSC in ISS orbits.

DOI

Scopus

1

被引用数

(Scopus)
Unifying X-ray emission properties of large scale jets, hotspots and lobes in AGN

J Kataoka, L Stawarz

High Energy Gamma-Ray Astronomy 745 522 - 527 2005年 [査読有り]

　概要を見る

We examine a systematic comparison of jet-knots, hotspots and radio lobes recently observed with Chandra and ASCA. This report will discuss the origin of their X-ray emissions and investigate the dynamics of the jets. The data was compiled at well sampled radio (5 GHz) and X-ray frequencies (1keV) for more than 40 radio galaxies. We examined three models for the X-ray production: synchrotron (SYN), synchrotron self-Compton (SSC) and external Compton on CMB photons (EC). For the SYN sources - mostly jet-knots in nearby low-luminosity radio galaxies - X-ray photons are produced by ultrarelativistic electrons with energies 10- 100 TeV that must be accelerated in situ. For the other objects, conservatively classified as SSC or EC sources, a simple formulation of calculating the '' expected '' X-ray fluxes under an equipartition hypothesis is presented. We confirmed that the observed X-ray fluxes are close to the expected ones for nonrelativistic emitting plasma velocities in the case of radio lobes and majority of hotspots, whereas considerable fraction of jet-knots is too bright at X-rays to be explained in this way. We examined two possibilities to account for the discrepancy in a framework of the inverse-Compton model: (1) magnetic field is much smaller than the equipartition value, and (2) the jets are highly relativistic on kpc/Mpc scales. We also briefly discuss the other possibility, namely that the observed X-ray emission from all of the jet-knots is synchrotron in origin.

DOI

Scopus

1

被引用数

(Scopus)
活動銀河核の大規模ジェット：Ｘ線で探る構造とダイナミクス

片岡淳

天文月報 10月号 ( vol.98 ) 680 - 687 2005年

CiNii
Near-infrared, optical, and X-ray observations of the anomalous X-ray pulsar 4U 0142+61

M Morii, N Kawai, J Kataoka, Y Yatsu, N Kobayashi, H Terada

YOUNG NEUTRON STARS AND SUPERNOVA REMNANTS 35 ( 6 ) 1177 - 1180 2005年 [査読有り]

　概要を見る

We present results from the simultaneous observations of an anomalous X-ray pulsar (AXP) 4U 0142 + 61 on Sep. 2003. We used RXTE, Subaru, and UH88 telescopes to cover X-ray, near-infrared (NIR) (JHK'), and optical (BVRI) bands, respectively. We obtained a simultaneous broadband spectrum for the first time among AXPs. We found NIR excess in the spectrum, which may be another component different from the optical one. We also found a R band dip. We discuss the broadband spectrum covering the optical and X-ray bands in the framework of a self absorbed synchrotron emission from the magnetosphere of magnetar. We also discuss about the R band dip feature, which could put a restriction on the emission models of magnetars. (c) 2005 Published by Elsevier Ltd on behalf of COSPAR.

DOI

Scopus

18

被引用数

(Scopus)
Low energy response of a prototype detector array for the PoGO astronomical hard X-ray polarimeter

J. Kataoka, M. Kanal, T. Arimoto, T. Ikagawa, M. Saito, N. Ueno, R. Kawai, P. Blandford, T. Chen, G. Kamae, T. Madejski, J. Mizuno, H. Ng, T. Tajima, L. Thurston, A. Barbier, J. Harding, S. Krizmanic, J. Hunter, R. Mitchell, E. Streitmatter, R. Groth, D. Fernholtz, Y. Marlow, T. Saito, S. Takahashi, H. Gunji, Y. Sakurai, V. Fukazawa, P. Anderson, W. Carlson, M. Klamra, M. Pearce, S. Suhonen, F. Larsson, C. I. Ryde, G. Bjornsson, S. Bogaert, Kishimoto

Proceedings of SPIE - The International Society for Optical Engineering 5898 1 - 11 2005年

　概要を見る

The Polarized Gamma-ray Observer (PoGO) is a new balloon-borne instrument designed to measure polarization from astrophysical objects in the 30-200 keV range. It is under development for the first flight anticipated in 2008. PoGO is designed to minimize the background by an improved phoswich configuration, which enables a detection of 10 % polarization in a 100 mCrab source in a 6-8 hour observation. To achieve such high sensitivity, low energy response of the detector is important because the source count rate is generally dominated by the lowest energy photons. We have developed new PMT assemblies specifically designed for PoGO to read-out weak scintillation light of one photoelectron (1 p.e.) level. A beam test of a prototype detector array was conducted at the KEK Photon Factory, Tsukuba in Japan. The experimental data confirm that PoGO can detect polarization of 80-85 % polarized beam down to 30 keV with a modulation factor 0.25 ± 0.05.

DOI

Scopus

3

被引用数

(Scopus)
Chandra Observation of the Interaction between the Hot Plasma Nebula RCW 89 and the Pulsar Jet of PSR B1509-58

Yatsu et a

Advance in Space Research 35 1066 2005年
BGO readout with photodiodes as a soft gamma-ray detector at -30 deg

Nakamoto et

Nuclear Instruments and Method section-A 2005 536 - 136 2005年
HETE-2 localization and observations of the gamma-ray burst GRB 020813

Rie Sato, Takanori Sakamoto, Jun Kataoka, Atsumasa Yoshida, Motoko Suzuki, Junichi Kotoku, Yuji Urata, Yoshihisa Yamamoto, Makoto Arimoto, Toru Tamagawa, Yuji Shirasaki, Ken'ichi Torii, Masaru Matsuoka, Yujin Nakagawa, Toru Yamazaki, Kaoru Tanaka, Miki Maetou, Makoto Yamauchi, Kunio Takagishi, Donald Q. Lamb, Jean-Luc Atteia, Roland Vanderspek, Carlo Graziani, Gregory Prigozhin, Joel Villasenor, J. Garrett Jernigan, Geoffrey B. Crew, Kevin Hurley, George R. Ricker, Stanford E. Woosley, Nat Butler, Al Levine, John P. Doty, Timothy Q. Donaghy, Edward E. Fenimore, Mark Galassi, Michel Boer, Jean-Pascal Dezalay, Jean-François Olive, Joao Braga, Ravi Manchanda, Graziella Pizzichini, Nobuyuki Kawai

Publications of the Astronomical Society of Japan 57 ( 6 ) 1031 - 1039 2005年

　概要を見る

A bright, long gamma-ray burst (GRB) was detected and localized by the instruments on board the High Energy Transient Explorer 2 satellite (HETE-2) at 02:44:19.17 UTC (9859.17 s UT) on 2002 August 13. The location was reported to the GRB Coordinates Network (GCN) about 4 min after the burst. In the prompt emission, the burst had a duration of approximately 125 s, and more than four peaks. We analyzed the time-resolved 2-400 keV energy spectra of the prompt emission of GRB 020813 using the Wide Field X-Ray Monitor (WXM) and the French Gamma Telescope (FREGATE) in detail. We found that the early part of the burst (17-52 s after the burst trigger) shows a depletion of low-energy photons below about 50 keV. It is difficult to explain the depletion by either synchrotron self-absorption or Comptonization. One possibility is that the low-energy depletion may be understood as a mixture of "jitter" radiation with the usual synchrotron radiation component. © 2005. Astronomical Society of Japan.

DOI

Scopus

5

被引用数

(Scopus)
Evolution of the synchrotron spectrum in Markarian 421 during the 1998 campaign

C Tanihata, J Kataoka, T Takahashi, GM Madejski

ASTROPHYSICAL JOURNAL 601 ( 2 ) 759 - 770 2004年02月 [査読有り]

　概要を見る

The uninterrupted 7 day ASCA observations of the TeV blazar Mrk 421 in 1998 have clearly revealed that X-ray flares occur repeatedly. In this paper, we present the results of the time-resolved spectral analysis of the combined data taken by ASCA, RXTE, BeppoSAX, and the Extreme Ultraviolet Explorer (EUVE). In this object-and in many other TeV blazars-the precise measurement of the shape of the X-ray spectrum, which reflects the high-energy portion of the synchrotron component, is crucial in determining the high-energy cutoff of the accelerated electrons in the jet. Thanks to the simultaneous broadband coverage, we measured the 0.1-25 keV spectrum resolved on timescales as short as several hours, providing a great opportunity to investigate the detailed spectral evolution at the flares. By analyzing the time-subdivided observations, we parameterize the evolution of the synchrotron peak, where the radiation power dominates, by fitting the combined spectra with a quadratic form [where the nuF(nu) flux at the energy E obeys log nuF(nu)( E)=log (nuF(nu), (peak))-const(log E-log E-peak)(2)]. In this case, we show that there is an overall trend that the peak energy E-peak and peak flux nuF(nu,pea)k increase or decrease together. The relation of the two parameters is best described as E-peak proportional to nuF(nu,peak)(0.7) for the 1998 campaign. Similar results were derived for the 1997 observations, while the relation gave a smaller index when both 1997 and 1998 data were included. On the other hand, we show that this relation, and also the detailed spectral variations, differs from flare to flare within the 1998 campaign. We suggest that the observed features are consistent with the idea that flares are due to the appearance of a new spectral component. With the availability of the simultaneous TeV data, we also show that there exists a clear correlation between the synchrotron peak flux and the TeV flux.

DOI

Scopus

44

被引用数

(Scopus)
Development of large area avalanche photodiode for future space research

Tomoko Ikagawa, Jun Kataoka, Nobuyuki Kawai

Progress of Theoretical Physics Supplement 155 345 - 346 2004年

　概要を見る

We report on the performance of recent avalanche photodiodes (APDs) produced by Hamamatsu photonics as a new X-ray and γ-ray detector. An FWHM energy resolution of 6.5% was obtained for direct detection of 5.9 keV X-rays, whereas 9.4% was obtained for 59.5 keV γ-rays measured with a CsI crystal. Because of their small volumes and low operating bias voltage, APDs are promising devices for future space research. We are planning to use them for our small satellites, CUTE-1.7 and Hu-ring.

DOI

Scopus
Particle acceleration and energy transport in the relativistic jets

Jun Kataoka

Progress of Theoretical Physics Supplement 155 351 - 352 2004年

　概要を見る

The vast bulk of cosmic-ray (CR) nuclei and electrons are thought to be accelerated in the shock waves of SNRs. The location of strong shocks and more extended structures than SNRs can potentially accelerate particles above 100 TeV. The Chandra X-ray Observatory has now resolved the X-ray spatial structure along jets, from kpc to Mpc, of more than a dozen of radio galaxies. These observations have established that particles are accelerated efficiently in radio galaxies, up to energies of 10-100 TeV. I present recent progress in the Chandra observation of AGN jets and discuss the energy transport from the vicinity of the central black hole to the kpc scale jets.

DOI

Scopus
The observational response of MAXI onboard ISS

Naoki Isobe, Masaru Matsuoka, Shiro Ueno, Hiroshi Tomida, Kazuyoshi Kawasaki, Haruyoshi Katayama, Tatehiro Mihara, Mitsuhiro Kohama, Ikuya Sakurai, Motoki Nakajima, Nobuyuki Kawai, Jun Kataoka, Atsumasa Yoshida, Daiki Takahashi, Masami Uzawa, Hiroshi Tsunemi, Emi Miyata, Isao Tanaka

Proceedings of SPIE - The International Society for Optical Engineering 5165 354 - 365 2004年

　概要を見る

The current status is reported of the development of Monitor of All-sky X-ray Image and the measurement of its observational response. MAXI is a scanning X-ray camera to be attached to the Japanese Experiment Module of the International Space Station in 2008. MAXI is mainly composed of two kinds of instruments, GSC which is sensitive to the 2 - 30 keV photons, and SSC to the 0.5 - 10 keV ones. As an X-ray all-sky monitor, MAXI has an unprecedented sensitivity of 7 mCrab in one orbit scan, and 1 mCrab in one week. Using the engineering mode of the proportional counter and of the collimator for GSC, the observational response of GSC is extensively measured. The acceptable performances are obtained as a whole for both the collimator and the counter. The engineering models of the other part of MAXI are also constructed and the measurement of their performance is ongoing.

DOI

Scopus

9

被引用数

(Scopus)
Hu-ring: A small university satellite for gamma-ray burst

N. Kawai, H. Okada, N. Miyashita, T. Urabe, M. Kashiwa, T. Tachikawa, N. Yamaguchi, K. Omagari, I. Morita, Y. Yamamoto, Y. Yatsu, T. Ikagawa, J. Kataoka, S. Matunaga

Proceedings of SPIE - The International Society for Optical Engineering 5488 ( PART 2 ) 967 - 976 2004年

　概要を見る

We propose a university-class micro-satellite "Hu-ring" to localize and study gamma-ray bursts. The primary mission of Hu-ring is to localize gamma-ray bursts with an 10́ accuracy in real time, and transmit promptly the coordinates to the ground. Although many of its mission concepts are modeled after HETE-2, use of avalanche photodiodes (APDs), innovative photon detector device, make it possible to further reduce the size and the mass of the satellite. We designed Hu-ring within a size of 50 cm cube and a weight limit of 50 kg, so that it can be launched as a piggy-back payload of the Japanese H-IIA Launch Vehicle. The satellite is spin-stabilized, and has a half-sky field of view centered on the anti-sun direction. A set of scintillation counters equipped with rotation modulation collimators are employed for localization of GRBs. We also measure the soft/medium X-ray spectra of GRBs using APDs as a direct X-ray photon detectors. These two kinds of instruments cover the 0.5-200 keV energy range. The satellite bus is designed mostly with commercially available components in order to reduce the cost and the lead time. Following the HETE-2 model, in order to receive the prompt burst alerts it is designed to rely on a global network of receive-only low-cost ground stations, which may be hosted at research instutions with a small footprint. We performed analyses in many aspects: mechanical and thermal design of the satellite bus, attitude control simulations, power budget, ground contact schedule and downlink capacity, etc. We verified that the mission goal can be achieved with this proposed design philosophy.

DOI

Scopus

2

被引用数

(Scopus)
Development status and performance estimation of MAXI

Shiro Ueno, Hiroshi Tomida, Naoki Isobe, Haruyoshi Katayama, Kazuyoshi Kawasaki, Takao Yokota, Naoyuki Kuramata, Masaru Matsuoka, Tatehiro Mihara, Ikuya Sakurai, Motoki Nakajima, Mitsuhiro Kohama, Hiroshi Tsunemi, Emi Miyata, Nobuyuki Kawai, Jun Kataoka, Yuuri Serino, Yoshihisa Yamamoto, Atsumasa Yoshida, Hitoshi Negor

Proceedings of SPIE - The International Society for Optical Engineering 5488 ( PART 1 ) 197 - 208 2004年

　概要を見る

Monitor of All-sky X-ray Image (MAXI) is an X-ray all-sky monitor, which will be delivered to the International Space Station (ISS) in 2008, to scan almost the whole sky once every 96 minutes for a mission life of two years. The detection sensitivity will be 7 mCrab (5σ level) in one scan, and 1 mCrab for one-week accumulation. At previous SPIE meetings, we presented the development status of the MAXI payload, in particular its X-ray detectors. In this paper, we present the whole picture of the MAXI system, including the downlink path and the MAXI ground system. We also examine the MAXI system components other than X-ray detectors from the point of view of the overall performance of the mission. The engineering model test of the MAXI X-ray slit collimator shows that we can achieve the position determination accuracy of <0.1 degrees, required for the ease of follow-up observations. Assessing the downlink paths, we currently estimates that the MAXI ground system receive more than 50% of the observational data in "real time" (with time delay of a few to ten seconds), and the rest of data with delay of 20 minutes to a few hours from detection, depending on the timing of downlink. The data will be processed in easily-utilised formats, and made open to public users through the Internet.

DOI

Scopus

8

被引用数

(Scopus)
Robotic telescope for rapid gamma-ray burst follow-up observations

R. Sato, N. Kawai, M. Suzuki, Y. Yatsu, J. Kataoka

Proceedings of SPIE - The International Society for Optical Engineering 5492 ( PART 2 ) 859 - 870 2004年

　概要を見る

We have developed a robotic telescope at Tokyo Institute of Technology (Tokyo Tech) to perform rapid follow-up observations of early optical afterglows of gamma-ray bursts (GRBs). Our system was primarily designed to respond quickly to the GRB locations notified by the High Energy Transient Explorer 2 (HETE-2) satellite, but it can also respond to all the notifications provided by the GRB Coordinates Network (GCN). In order to cover the error circle of the HETE-2, wide-field and thermo-electrically cooled CCD camera is equipped on the focus of a small 30cm telescope. A field of view of our system is 44 arcminutes which can cover the most error circles of the HETE-2. The rapid response (less than 15 sec after the notice) and slew speeds (6 deg / sec) make our system appropriate for observing GRB afterglows. Using this convenient system, we detected the optical afterglow of GRB 030329. Observation was started 67 minutes after the burst, which was one of the earliest detection in the world. We report the performance of our telescope coupled to CCD camera, and estimate the limiting magnitude of our system. Although our system is located in a region affected by strong city lights, the limiting magnitude is approximately 17.3 mag.

DOI

Scopus
Large-area balloon-borne polarized gamma ray observer (PoGO)

R Blanford, P Chen, T Kamae, G Madejski, J Ng, T Mizuno, H Tajima, T Thurston, L Barbier, P Bloser, T Cline, S Hunter, A Harding, J Krizmanic, J Mitchell, R Streitmatter, J Tueller, E Groth, R Fernholz, D Marlow, G Bogaert, S Gunji, H Sakurai, Y Saito, T Takahashi, J Kataoka, N Kawai, Y Fukazawa, P Carlson, W Klamra, M Pearce, CI Bjornsson, C Fransson, S Larsson, F Ryde

2003 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORD, VOLS 1-5 1708 - 1713 2004年 [査読有り]

　概要を見る

We are developing a new balloon-borne instrument (PoGO), to measure polarization of soft gamma rays (25-200 keV) using asymmetry in azimuth angle distribution of Compton scattering. PoGO will detect 10% polarization in 100m Crab sources in a 6-8 hour observation and bring a new dimension to studies on gamma ray emission/transportation mechanism in pulsars, AGNs, black hole binaries, and neutron star surface. The concept is an adaptation to polarization measurements of well-type phoswich counter technology used in balloon-borne experiments (Welcome-1) and AstroE2 Hard X-ray Detector. PoGO consists of close-packed array of 397 hexagonal well-type phoswich counters. Each unit is composed of a long thin tube (well) of slow plastic scintillator, a solid rod of fast plastic scintillator, and a short BGO at the base. A photomultiplier coupled to the end of the BGO detects light from all 3 scintillators.
The rods with decay times < 10 ns, are used as the active elements; while the wells and BGOs, with decay times similar to 250 ns are used as active anti-coincidence. The fast and slow signals are separated out electronically.
When gamma rays entering the field-of-view (fwhmsimilar to 3deg(2)) strike a fast scintillator, some are Compton scattered. A fraction of the scattered photons are absorbed in another rod (or undergo a second scatter). A valid evnet requires one clean fast signal of pulse-height compatible with photo-absorption (> 20keV) and one or more compatible with Compton scattering (< 10keV). Studies based on EGS4 (with polarization features) and Geant4 predict excellent background rejection and high sensitivity.
The next gamma-ray satellite GLAST for BLAZAR observations

Fukazawa, Y, Obsugi, T, Yoshida, S, Kamae, T, Mizuno, T, Takahashi, T, Ozaki, M, Kawai, N, Kataoka, J

PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT 155 ( 155 ) 327 - 328 2004年 [査読有り]

　概要を見る

The next gamma-ray satellite GLAST will be launched in 2007, under the cooperation of the USA, Japan, Italy, France, Sweden, and so on. GLAST sensitivity is several tens times higher than the EGRET, thanks to good position determination, large effective area, and wide field of view. The key technology to achieve these capabilities is low-noise silicon-strip-detector" (SSD), developed and designed by Hiroshima University and Hamamatsu Photonics. Most of the GLAST SSD has been produced, and found to be very high-quality devices with quite a low rate of dead channels of < 0.01%. The detector assembly has started, and soon one tower will become built for various environmental tests. GLAST will detect several thousands of BLAZARs, and thus enable us to probe the jet mechanisms and evolution of massive black holes. Good position accuracy will in addition increase an identification. The high-sensitivity, wide-energy-band, and continuous-long-time observations of BLAZARs with GLAST LAT will be hoped to open a new epoch of massive black-hole observations. Especially, the flare history is very important to consider the jet mechanims and particle acceleration."

DOI

Scopus
Design and performance of soft gamma-ray detector for NeXT mission

Tajima H, Kamae T, Madejski G, Mitani T, Nakazawa K, Tanaka T, Takahashi T, Watanabe S, Fukazawa Y, Ikagawa T, Kataoka J, Kokubun M, Makishima K, Terada Y, Nomachi M, Tashiro M

2004 IEEE Nuclear Science Symposium Conference Record, Vols 1-7 314 - 321 2004年 [査読有り]
Wide band X-ray Imager (WXI) and Soft Gamma-ray Detector (SGD) for the NeXT Mission

Takahashi T, Awaki A, Dotani T, Fukazawa Y, Hayashida K, Kamae T, Kataoka J, Kawai N, Kitamoto S, Kohmura T, Kokubun M, Koyama K, Makishima K, Matsumoto H, Miyata E, Murakami T, Nakazawa K, Nomachi M, Ozaki M, Tajima H, Tashiro M, Tamagawa T, Terada Y, Tsunemi H, Tsuru T, Yamaoka K, Yonetoku D, Yoshida A

Proceedings of SPIE - The International Society for Optical Engineering 5488 ( PART 2 ) 549 - 560 2004年 [査読有り]

DOI

Scopus

52

被引用数

(Scopus)
Earliest detection of the optical afterglow of GRB 030329 and its variability

R Sato, N Kawai, M Suzuki, Y Yatsu, J Kataoka, R Takagi, K Yanagisawa, H Yamaoka

PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT 599 ( 155 ) 411 - 412 2004年 [査読有り]

　概要を見る

We report an earliest detection of an optical afterglow of GRB 030329 at the Tokyo Institute of Technology (Tokyo, Japan). Our observation started 67 minutes after the burst and continued for two succeeding nights. Combining our data with those reported in GCN, we find that the early afterglow light curve of the first half day is described by a broken power-law, (alpha t(-alpha)) function with indices alpha(1) = 0.88 +/- 0.01 (0.047 days < t < t(b1)), alpha(2) = 1.18 +/- 0.01 (t(b1) < t < t(b2)), and alpha(3) = 1.81 +/- 0.04 (t(b2) < t < 1.2 days), where t(b1) similar to 0.26 days and t(b2) similar to 0.54 days, respectively. The change of the power-law index at the first break at t similar to 0.26 days is consistent with that expected from a "cooling break".

DOI

Scopus
Performance of the most recent avalanche photodiodes for future X-ray and gamma-ray astronomy

J Kataoka, T Ikagawa, Y Yatsu, Y Kuramoto, T Saito, N Kawai, Y Serino, J Kotoku, Y Ishikawa, N Kawabata

HIGH-ENERGY DETECTORS IN ASTRONOMY 5501 249 - 260 2004年 [査読有り]

　概要を見る

We report on the performance of the most recent avalanche photodiodes produced by Hamamatsu Photonics, as low-energy X-rays and gamma-rays detectors. APDs share good features of both photo diodes and PMTs, as they are very compact, produce an internal gain of 10-100, and have high quantum efficiency close to 100% in the visible right. Until very recently, however, APDs were limited to very small surfaces, and were mainly used as a digital device for light communication. We have developed large area (up to 10x10 mm(2)) APDs which can be used in the physics experiments. The best energy resolution of 6.4% (FWHM) was obtained in direct detection of 5.9 keV X-rays. The FWHM results of 9.4% and 4.9% were obtained for 59.5 keV and 662 keV gamma-rays respectively, as measured with the CsI(Tl) crystal. The minimum detectable energy for the scintillation light was as low as 1 keV at lightly cooled environment (-20degreesC). Note that our results are the best records ever achieved with APDs. Various applications of APDs are presented for future space research and nuclear medicine. In particular 2-dimensional APD arrays will be a promising device for a wide-band X-ray and gamma-ray imaging detector.

DOI

Scopus

12

被引用数

(Scopus)
Ground Support Electronics for testing the preflight performance of the MAXI-GSC

J Kataoka, Y Serino, N Kawai, T Arakuni, A Yoshida, M Uzawa, M Kohama, Sakurai, I, T Mihara, H Negoro, N Isobe, H Katayama, K Kawasaki, N Kuramata, M Matsuoka, H Tomida, S Ueno, T Yokota, E Miyata, M Nomachi, H Tsunemi

X-RAY AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY XIII 5165 375 - 386 2004年 [査読有り]

　概要を見る

MAXI is an X-ray all-sky monitor which will be mounted on the Japanese Experimental Module (JEM) of the International Space Station (ISS) in 2008. The Gas Slit Camera (GSC) consists of 12 one-dimensional position sensitive proportional counters and the sensitivity will be as high as 1 mCrab for a one-week accumulation in the 2-30 keV band. In order to calibrate the detectors and electronic systems thoroughly before the launch, a fast and versatile Ground Support Electronic (GSE) system is necessary. We have developed a new GSE based on VME I/O boards for a Linux workstation. These boards carry reconfigurable FPGAs of 100,000 gates, together with 16 Mbytes of SDRAM. As a demonstration application of using this GSE, we have tested the positional response of a GSC engineering counter. We present a schematic view of the GSE highlighting the functional design, together with a future vision of the ground testing of the GSC flight counters and digital associated processor.

DOI

Scopus
Performance of large-area avalanche photodiode for low-energy X-rays and gamma-rays scintillation detection

Ikagawa, T, Kataoka, J, Yatsu, Y, Kawai, N, Mori, K, Kamae, T, Tajima, H, Mizuno, T, Fukazawa, Y, Ishikawa, Y

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 515 ( 3 ) 671 - 679 2003年12月 [査読有り]

　概要を見る

We report on the performance of large-area (5 x 5 mm(2)) avalanche photodiodes (APD) produced by Hamamatsu Photonics, as a low-energy X-rays and gamma-rays scintillation detector. Hamamatsu APD has a reverse structure and works at relatively low bias voltage of 300-350 V. The leakage current is 1.2 nA at room temperature (25degreesC) and decreases to 10 pA at -20degreesC for an avalanche gain of 50. The best FWHM energy resolutions of 9.4+/-0.3% and 7.4+/-0.3% were obtained for 59.5 keV gamma-rays from Am-241 and 122 keV gamma-rays from Co-57 sources, respectively, as measured with a 5 x 5 x 5mm(3) cubic CsI(TI) crystal. We show that the minimum detectable energy for the scintillation light is remarkably low; 4.6 keV at room temperature (20degreesC) and 1.1 keV at -20degreesC. 5.9 keV X-rays from Fe-55 were clearly resolved at -20degreesC with an FWHM resolution of 32.9+/-0.3%. These results suggest that Hamamatsu APD can be a promising device for future applications in low-energy scintillation detection. (C) 2003 Elsevier B.V. All rights reserved.

DOI

Scopus

60

被引用数

(Scopus)
Chandra observation of the anomalous X-ray pulsar 1E 1841-045

M Morii, R Sato, J Kataoka, N Kawai

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 55 ( 3 ) L45 - L48 2003年06月 [査読有り]

　概要を見る

We present the results from a Chandra ACIS CC mode observation of an anomalous X-ray pulsar (AXP) 1E 1841-045. This was the first observation in which the pulsar spectrum over a wide energy range was spatially discriminated from the surrounding SNR, Kes 73. Like other AXPs, the phase-integrated spectrum was fitted well with a power-law plus blackbody model. The spectral parameters are Gamma = 2.0 +/- 0.3, kT(BB) = 0.44 +/- 0.02 keV, and N-H = 2.54(-0.13)(+0.15) x 10(22)cm(-2). This photon index is the flattest among AXPs, and resembles soft gamma-ray repeaters (SGRs) in a quiescent state. The pulse profile is double-peaked, and we found that the second peak has a significantly hard spectrum. The spectra of all phases are consistent with a power-law plus blackbody model with a constant temperature and photon index. When fitted with a two-blackbody model, we obtained a similarly good fit. These results can be interpreted by saying that there are two emission regions with different energy spectra.

DOI

Scopus

43

被引用数

(Scopus)
Implications of variability patterns observed in TeV blazars on the structure of the inner jet

C Tanihata, T Takahashi, J Kataoka, GM Madejski

ASTROPHYSICAL JOURNAL 584 ( 1 ) 153 - 163 2003年02月 [査読有り]

　概要を見る

The recent long-look X-ray observations of TeV blazars have revealed many important new features concerning their time variability. In this paper we suggest a physical interpretation for those features based on the framework of the internal and external shock scenarios. We present a simplified model applicable to TeV blazars and investigate through simulations how each of the model parameters would affect the observed light curve or spectrum. In particular, we show that the internal shock scenario naturally leads to all the observed variability properties, including the structure function, but for it to be applicable, the fractional fluctuation of the initial bulk Lorentz factors must be small, sigma'(Gamma) = sigma(Gamma)/Gamma(avg) << 0.01. This implies very low dynamical efficiency of the internal shock scenario. We also suggest that several observational quantities such as the characteristic timescale, the relative amplitude of flares as compared to the steady ("offset") component, and the slope of the structure function can be used to probe the inner jet. The results are applied to the TeV blazar Mrk 421, and this, within the context of the model, leads to the determination of several physical parameters: the ejection of a shell with average thickness of similar to10(13) cm occurs on average every 10 minutes, and the shells collide similar to10(17) cm away from the central source.

DOI

Scopus

34

被引用数

(Scopus)
Chandra detection of hotspot and knots of 3C 303

J Kataoka, P Edwards, M Georganopoulos, F Takahara, S Wagner

ASTRONOMY & ASTROPHYSICS 399 ( 1 ) 91 - 97 2003年02月 [査読有り]

　概要を見る

We report the detection at X-rays of the radio/optical hotspot and knots of 3C 303 from a short (15 ksec) Chandra exposure in 2001 March. The X-ray morphology is similar to that of the radio/optical emission with peaks in the X-ray emission found at 5.5" (knot B), 9" (knot C) and 17" (hotspot) from the core of 3C 303. Despite the limited signal-to-noise ratio of the short Chandra exposure, the X-ray photon spectrum was measured for the hotspot. We construct the spectral energy distribution (SED) and find that the X-ray flux is well below the extrapolation of the radio-to-optical continuum, which we interpret as resulting from the production of X-rays via inverse Compton scattering of both synchrotron photons (SSC) and cosmic microwave background photons (EC/CMB). The magnetic field strength, region size, and the maximum energy of electrons are self-consistently determined for the hotspot to be B similar or equal to 4.3 muG, R similar or equal to 6.5 x 10(21) cm, and gamma(max) similar or equal to 1.4 x 10(7). This implies a magnetic field strength a factor of similar to30 below the equipartition value; B-eq 150 muG. The origin of this large departure from equipartition is still uncertain, but the discrepancy is reduced if the plasma in the hotspot is moving with mildly relativistic speeds. Our observation of 3C 303, as well as recent Chandra detections of large scale jets and hotspots in a number of radio galaxies, confirm that particles are accelerated very efficiently in radio galaxies.

DOI

Scopus

39

被引用数

(Scopus)
Large-area balloon-borne polarized gamma ray observer (PoGO)

Roger Blanford, Psin Chen, Tuneyoshi Kamae, Grzegorz Madejski, Johnny Ng, Tsunefumi Mizuno, Hiroyasu Tajima, Timothy Thurston, Louis Barbier, Peter Bloser, Thomas Cline, Stanley Hunter, Alice Harding, John Krizmanic, John Mitchell, Robert Streitmatter, Jack Tueller, Edward Groth, Richard Fernholz, Daniel Marlow, Gilles Bogaert, Shuichi Gunji, Hirohisa Sakurai, Yoshitaka Saito, Tadayuki Takahashi, Jun Kataoka, Nobuyuki Kawai, Yasushi Fukazawa, Per Carlson, Wlodzimierz Klamra, Mark Pearce, Claes Ingvar Bjornsson, Claes Fransson, Stefan Larsson, Felix Ryde

IEEE Nuclear Science Symposium Conference Record 3 1708 - 1713 2003年 [査読有り]

　概要を見る

We are developing a new balloon-borne instrument (PoGO), to measure polarization of soft gamma rays (25-200 keV) using asymmetry in azimuth angle distribution of Compton scattering. PoGO will detect 10% polarization in 100mCrab sources in a 6-8 hour observation and bring a new dimension to studies on gamma ray emission/transportation mechanism in pulsars, AGNs, black hole binaries, and neutron star surface. The concept is an adaptation to polarization measurements of well-type phoswich counter technology used in balloon-borne experiments (Welcome-1) and AstroE2 Hard X-ray Detector. PoGO consists of close-packed array of 397 hexagonal well-type phoswich counters. Each unit is composed of a long thin tube (well) of slow plastic scintillator, a solid rod of fast plastic scintillator, and a short BGO at the base. A photomultiplier coupled to the end of the BGO detects light from all 3 scintillators. The rods with decay times < 10 ns, are used as the active elements; while the wells and BGOs, with decay times ∼ 250 ns are used as active anti-coincidence. The fast and slow signals are separated out electronically. When gamma rays entering the field-of-view (fwhm∼ 3deg 2) strike a fast scintillator, some are Compton scattered. A fraction of the scattered photons are absorbed in another rod (or undergo a second scatter). A valid evnet requires one clean fast signal of pulse-height compatible with photo-absorption (> 20keV) and one or more compatible with Compton scattering (< 10keV). Studies based on EGS4 (with polarization features) and Geant4 predict excellent background rejection and high sensitivity.
Performance of Large Area Avalanche Photodiode as a Low Signal Photon Detector

Ikagawa et

Nuclear Instruments and Method section-A 515 663 - 663 2003年

CiNii
Chandra Discovery of an X-ray Jet and Lobes in 3C15

J.Kataoka

Astronomy & Astrophysics 410 833 2003年
RXTE observations of 3C 273 between 1996 and 2000: variability time-scale and jet power

J Kataoka, C Tanihata, N Kawai, F Takahara, T Takahashi, PG Edwards, F Makino

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 336 ( 3 ) 932 - 944 2002年11月 [査読有り]

　概要を見る

We present the results of a long-look monitoring of 3C 273 with RXTE between 1996 and 2000. A total of 230 observations amounts to a net exposure of 845 ks, with this spectral and variability analysis of 3C 273 covering the longest observation period available at hard X-ray energies. Flux variations by a factor of 4 have been detected over 4 yr, whereas flux variations of less than 30 per cent have been observed for individual flares on time-scales of similar to3 d. Two temporal methods, the power spectrum density (PSD) and the structure function (SF), have been used to study the variability characteristics of 3C 273. The hard X-ray photon spectra generally show a power-law shape with a differential photon index of Gamma similar or equal to 1.6 +/- 0.1. In 10 of 261 data segments, exceptions to power-law behaviour have been found: (i) an additional soft excess below 4 keV; and (ii) a broad Fe fluorescent line feature with EW similar to 100-200 eV. Our new observations of these previously reported X-ray features may imply that 3C 273 is a unique object whose hard X-ray emission occasionally contains a component that is not related to a beamed emission (Seyfert-like), but most hard X-rays are likely to originate in inverse Compton radiation from the relativistic jet (blazar-like). Multifrequency spectra from radio to gamma-rays are presented in addition to our RXTE results. The X-ray time variability and spectral evolution are discussed in the framework of the beamed, synchrotron self-Compton picture. We consider the 'power balance' (both radiative and kinetic) between the accretion disc, the sub-parsec-scale jet and the 10-kpc-scale jet.

DOI

Scopus

39

被引用数

(Scopus)
Observation of gamma rays greater than 10 TeV from Markarian 421

K Okumura, A Asahara, GV Bicknell, PG Edwards, R Enomoto, S Gunji, S Hara, T Hara, S Hayashi, C Itoh, S Kabuki, F Kajino, H Katagiri, J Kataoka, A Kawachi, T Kifune, H Kubo, J Kushida, S Maeda, A Maeshiro, Y Matsubara, Y Mizumoto, M Mori, M Moriya, H Muraishi, Y Muraki, T Naito, T Nakase, K Nishijima, M Ohishi, Patterson, JR, K Sakurazawa, R Suzuki, DL Swaby, K Takano, T Takano, T Tanimori, F Tokanai, K Tsuchiya, H Tsunoo, K Uruma, A Watanabe, S Yanagita, T Yoshida, T Yoshikoshi

ASTROPHYSICAL JOURNAL 579 ( 1 ) L9 - L12 2002年11月 [査読有り]

　概要を見る

We have observed Markarian 421 in 2001 January and March with the CANGAROO-II imaging Cerenkov telescope during an extraordinarily high state at TeV energies. From 14 hr of observations at very large zenith angles, similar to70degrees, a signal of 298 +/- 52 gamma-ray-like events (5.7 sigma) was detected at E > 10 TeV, where a higher sensitivity is achieved than those of usual observations near the zenith, owing to a greatly increased collecting area. Under the assumption of an intrinsic power-law spectrum, we derived a differential energy spectrum dN/dE p (3.3 +/- 0.9(stat) +/- 0.3(syst)) x 10(-13) (E/10 TeV)(-(4.0+/-0.60.9, stat +/-0.3syst)) photons cm(-2) s(-1) TeV-1, which is steeper than those previously measured around 1 TeV and supports the evidence for a cutoff in the spectrum of Mrk 421. However, the 4 sigma excess at energies greater than 20 TeV in our data favors a cutoff energy of similar to8 TeV, at the upper end of the range previously reported from measurements at TeV energies.

DOI

Scopus

25

被引用数

(Scopus)
Performance of the ASTRO-E hard X-ray detector

M Tashiro, T Kamae, K Makishima, T Takahashi, T Murakami, Y Fukazawa, M Kokubun, K Nakazawa, M Nomachi, A Yoshida, Y Ezoe, N Isobe, N Iyomoto, J Kataoka, J Kotoku, M Kouda, S Kubo, A Kubota, Y Matsumoto, T Mizuno, GM Madejski, Y Okada, N Ota, H Ozawa, G Sato, M Sugiho, M Sugizaki, Takahashi, I, H Takahashi, T Tamura, C Tanihata, Y Terada, Y Uchiyama, S Watanabe, K Yamaoka, D Yonetoku

IEEE TRANSACTIONS ON NUCLEAR SCIENCE 49 ( 4 ) 1893 - 1897 2002年08月 [査読有り]

　概要を見る

This paper summarizes the design and performance of the hard X-ray detector constructed for the ASTRO-E satellite. The detector utilizes the GSO/BGO well-type phoswich counters in a compound-eye configuration to achieve an extremely low background level of a few x 10(-5) counts s(-1) cm(-2)keV(-1) [1]. The GSO scintillators installed in the BGO active shield wells are sensitive to 30-600 keV photons, while the 2-mm-thick silicon PIN diodes, placed in front of each GSO crystal, cover the 10-60 keV energy band with a spectral resolution of similar to3.5-keV full-width at half-maximum. The design goals, of both low background and high energy resolution, in the hard X-ray bands were verified through the preflight calibration experiments.

DOI

Scopus

26

被引用数

(Scopus)
The acceleration of cosmic-ray protons in the supernova remnant RX J1713.7-3946

R Enomoto, T Tanimori, T Naito, T Yoshida, S Yanagita, M Mori, PG Edwards, A Asahara, GV Bicknell, S Gunji, S Hara, T Hara, S Hayashi, C Itoh, S Kabuki, F Kajino, H Katagiri, J Kataoka, A Kawachi, T Kifune, H Kubo, J Kushida, S Maeda, A Maeshiro, Y Matsubara, Y Mizumoto, M Moriya, H Muraishi, Y Muraki, T Nakase, K Nishijima, M Ohishi, K Okumura, Patterson, JR, K Sakurazawa, R Suzuki, DL Swaby, K Takano, T Takano, F Tokanai, K Tsuchiya, H Tsunoo, K Uruma, A Watanabe, T Yoshikoshi

NATURE 416 ( 6883 ) 823 - 826 2002年04月 [査読有り]

　概要を見る

Protons with energies up to similar to10(15) eV are the main component(1) of cosmic rays, but evidence for the specific locations where they could have been accelerated to these energies has been lacking(2). Electrons are known to be accelerated to cosmic-ray energies in supernova remnants(3,4), and the shock waves associated with such remnants, when they hit the surrounding interstellar medium, could also provide the energy to accelerate protons. The signature of such a process would be the decay of pions (pi(0)), which are generated when the protons collide with atoms and molecules in an interstellar cloud: pion decay results in gamma-rays with a particular spectral-energy distribution(5,6). Here we report the observation of cascade showers of optical photons resulting from g-rays at energies of similar to10(12) eV hitting Earth's upper atmosphere, in the direction of the supernova remnant RX J1713.7-3946. The spectrum is a good match to that predicted by pion decay, and cannot be explained by other mechanisms.

DOI PubMed

Scopus

231

被引用数

(Scopus)
Achievements of the ASTRO-E Hard X-ray Detector development

M Tashiro, K Makishima, T Kamae, T Murakami, T Takahashi, Y Fukazawa, M Kokubun, K Nakazawa, M Nomachi, A Yoshida, Y Ezoe, N Isobe, N Iyomoto, J Kataoka, J Kotoku, M Kouda, S Kubo, A Kubota, Y Matsumoto, T Mizuno, Y Okada, N Ota, H Ozawa, G Sato, M Sugiho, M Sugizaki, Takahashi, I, H Takahashi, T Tamura, C Tanihata, Y Terada, Y Uchiyama, S Watanabe, K Yamaoka, D Yonetoku

2001 IEEE NUCLEAR SCIENCE SYMPOSIUM, CONFERENCE RECORDS, VOLS 1-4 1 483 - 486 2002年 [査読有り]

　概要を見る

The ASTRO-E Hard X-ray Detector utilized GSO/BGO well-type phoswich counters in compound-eye configuration [1], to achieve an extremely low background level of a few x 10(-5)counts s(-1) cm(-2) keV(-1). The GSO scintillators installed in the BGO active shield wells observes 30-600 keV photons, while silicon PIN diodes of 2 mm thick placed in front of each GSO crystal covers 10 - 60 keV photons with energy resolution of similar to3.5 keV FWHM. The design goals both of low background and high energy resolution in the hard X-ray bands were confirmed to be achieved through the preflight calibration experiments.
ブレーザーの他波長同時か観測と粒子加速への示唆

片岡淳他

天文月報 8月号 ( vol.95 ) 373 2002年
Design study of CANGAROO-III, stereoscopic imaging atmospheric Cherenkov telescopes for sub-TeV gamma-ray detection

R Enomoto, S Hara, A Asahara, GV Bicknell, PG Edwards, S Gunji, T Hara, J Jimbo, F Kajino, H Katagiri, J Kataoka, A Kawachi, T Kifune, H Kubo, J Kushida, Y Matsubara, Y Mizumoto, M Mori, M Moriya, H Muraishi, Y Muraki, T Naito, T Nakase, K Nishijima, K Okumura, Patterson, JR, K Sakurazawa, DL Swaby, K Takano, T Tanimori, T Tamura, K Tsuchiya, K Uruma, S Yanagita, T Yoshida, T Yoshikoshi, A Yuki

ASTROPARTICLE PHYSICS 16 ( 3 ) 235 - 244 2002年01月 [査読有り]

　概要を見る

CANGAROO-III is an imaging atmospheric Cherenkov telescope array of four 10-m telescopes for very high energy (sub-TeV) gamma-ray astronomy. A design study of the CANGAROO-III telescope system was carried out using the Monte Carlo technique in order to optimize the pixel size and the telescope spacing. Studies were also made of observations at low elevation angles. (C) 2002 Elsevier Science B.V. All rights reserved.

DOI

Scopus

52

被引用数

(Scopus)
Variability timescales of TeV blazars observed in the ASCA continuous long-look X-ray monitoring

C Tanihata, CM Urry, T Takahashi, J Kataoka, SJ Wagner, GM Madejski, M Tashiro, M Kouda

ASTROPHYSICAL JOURNAL 563 ( 2 ) 569 - 581 2001年12月 [査読有り]

　概要を見る

Three uninterrupted, long (lasting respectively 7, 10, and 10 days) ASCA observations of the well-studied TeV-bright blazars Mrk 421, Mrk 501, and PKS 2155-304 all show continuous strong X-ray flaring. Despite the relatively faint intensity states in two of the three sources, there was no identifiable quiescent period in any of the observations. Structure function analysis shows that all blazars have a characteristic timescale of similar to1 day, comparable to the recurrence time and to the timescale of the stronger flares. On the other hand, examination of these flares in more detail reveals that each of the strong flares is not a smooth increase and decrease but exhibits substructures of shorter flares having timescales of similar to 10 ks. We verify via simulations that in order to explain the observed structure function, these shorter flares ("shots") are unlikely to be fully random, but in some way are correlated with each other. The energy dependent cross-correlation analysis shows that interband lags are not universal in TeV blazars. This is important since in the past only positive detections of lags were reported. In this work, we determine that the sign of a lag may differ from flare to flare; significant lags of both signs were detected from several flares, while no significant lag was detected from others. However, we also argue that the nature of the underlying component can affect these values. The facts that all flares are nearly symmetric and that fast variability shorter than the characteristic timescale is strongly suppressed, support the scenario where the light crossing time dominates the variability timescales of the day-scale flares.

DOI

Scopus

68

被引用数

(Scopus)
Characteristic X-ray variability of TeV blazars: Probing the link between the jet and the central engine

J Kataoka, T Takahashi, SJ Wagner, N Iyomoto, PG Edwards, K Hayashida, S Inoue, GM Madejski, F Takahara, C Tanihata, N Kawai

ASTROPHYSICAL JOURNAL 560 ( 2 ) 659 - 674 2001年10月 [査読有り]

　概要を見る

We have studied the rapid X-ray variability of three extragalactic TeV gamma -ray sources : Mrk 421, Mrk 501, and PKS 2155-304. Analyzing the X-ray light curves obtained from ASCA and/or Rossi X-Ray Timing Explorer observations between 1993 and 1998, we have investigated the variability in the time domain from 10(3) to 10(8) s. For all three sources, both the power spectrum density (PSD) and the structure function (SF) show a rollover with a timescale of the order of 1 day or longer, which may be interpreted as the typical timescale of successive flare events. Although the exact shape of turnover is not well constrained and the low-frequency (long timescale) behavior is still unclear, the high-frequency (short timescale) behavior is clearly resolved. We found that, on timescales shorter than 1 day, there is only small power in the variability, as indicated by a steep power spectrum density of f(-2 similar to -3). This is very different from other types of mass-accreting black hole systems, for which the short-timescale variability is well characterized by a fractal, flickering-noise PSD (f(-1 similar to -2)). The steep PSD index and the characteristic timescale of flares imply that the X-ray-emitting site in the jet is of limited spatial extent : D greater than or equal to 10(17) cm distant from the base of the jet, which corresponds to greater than or equal to 10(2) Schwarzschild radii for 10(7-10) M-circle dot black hole systems.

DOI

Scopus

104

被引用数

(Scopus)
Spectral evolution of PKS 2155-304 during the ASCA long-look campaign

M Kouda, C Tanihata, T Takahashi, M Tashiro, J Kataoka

NEW CENTURY OF X-RAY ASTRONOMY 251 376 - 377 2001年 [査読有り]

　概要を見る

We collected all light curves of the TeV blazar PKS 2155-304, spanning over 12 years, obtained by both Ginga and ASCA. Taking the advantage that Ginga covers a higher energy range compared to ASCA, we confirmed the amplitude of the variations being larger at higher energies, which is consistent with the synchrotron picture of the X-ray jet. We also report on the recent ASCA continuous 10-day observation of this source. In spite of its low flux compared to previous observations, we detected significant daily variations, and found that there was actually no particular quiescent period throughout our observation.
活動銀河核からの高エネルギー放射：相対論的ジェットの物理

片岡淳

日本物理学会誌 vol.56 no.3 ( 3 ) 189 - 194 2001年

　概要を見る

近年,米国の天文衛星CGR0は270を越える天体からのガンマ線放射を検出し,高エネルギー宇宙物理の新しい窓を開いた.このうち66天体がブレーザーと呼ばれる活動銀河核である.ブレーザーでは磁場を伴うジェット内部で電子が相対論的速度まで加速され,その非熱的放射がビーミング効果で強められて観測される.本稿では近年の多波長同時観測の成果を中心に,相対論的ジェットにおける物理過程について解説する.

DOI CiNii
Rapid synchrotron flares from BL Lacertae detected by ASCA and RXTE

C Tanihata, T Takahashi, J Kataoka, GM Madejski, S Inoue, H Kubo, F Makino, Mattox, JR, N Kawai

ASTROPHYSICAL JOURNAL 543 ( 1 ) 124 - 130 2000年11月 [査読有り]

　概要を見る

We report the variable X-ray emission from BL Lacertae detected in the ASCA ToO observation conducted during the EGRET and RXTE pointings, coincident with the 1997 July outburst. The source showed a historically high state of X-ray, optical, and gamma -ray emission, with its 2-10 keV flux peaking at similar to3.3 x 10(-11) ergs cm(-2) s(-1). This is more than 3 times higher than the value measured by ASCA in 1995. Ne detected two rapid flares that occurred only in the soft X-ray band, while the hard X-ray flux also increased, but decayed with a much longer timescale. Together with the requirement of a very steep and varying power law dominating the soft X-ray band in addition to the hard power law, we suggest that both the high-energy end of the synchrotron spectrum and the hard inverse Compton spectrum were visible in this source during the outburst. We discuss the possible origins of the observed variability timescales, and interpret the short timescales of the soft X-ray variability as reflecting the size of the emission region.
Complex spectral variability from intensive multiwavelength monitoring of Markarian 421 in 1998

T Takahashi, J Kataoka, G Madejski, J Mattox, CM Urry, S Wagner, F Aharonian, M Catanese, L Chiappetti, P Coppi, B Degrange, G Fossati, H Kubo, H Krawczynski, F Makino, H Marshall, L Maraschi, F Piron, R Remillard, F Takahara, M Tashiro, H Terasranta, T Weekes

ASTROPHYSICAL JOURNAL 542 ( 2 ) L105 - L109 2000年10月 [査読有り]

　概要を見る

We conducted a multifrequency campaign for the TeV blazar Markarian 421 in 1998 April. The campaign started from a pronounced high-amplitude flare recorded by BeppoSAX and Whipple; the ASCA observation started 3 days later. In the X-ray data, we detected multiple flares, occurring on timescales of about 1 day. ASCA data clearly reveal spectral variability. The comparison of the data from ASCA, the Extreme Ultraviolet Explorer, and the Rossi X-Ray Timing Explorer indicates that the variability amplitudes in the low-energy synchrotron component are larger at higher photon energies. In TeV gamma -rays, large intraday variations-which were correlated with the X-ray flux-were observed when results from three Cerenkov telescopes were combined. The rms variability of TeV gamma -rays was similar to that observed in hard X-rays, above 10 keV. The X-ray light curve reveals flares that are almost symmetric for most cases, implying that the dominant timescale is the light crossing time through the emitting region. The structure function analysis based on the continuous X-ray light curve of 7 days indicates that the characteristic timescale is similar to0.5 days. The analysis of ASCA light curves in various energy bands appears to show both soft (positive) and hard (negative) lags. These may not be real, as systematic effects could also produce these lags, which are all much smaller than an orbit. If the lags of both signs are red, these imply that the particle acceleration and X-ray cooling timescales are similar.
Capability of the ASTRO-E Hard X-ray Detector for high-energy transients and gamma-ray bursts

Y Terada, K Yamaoka, M Kokubun, J Kotoku, T Mizuno, J Kataoka, T Takahasi, T Murakami, K Makishima, T Kamae

FIFTH COMPTON SYMPOSIUM 510 667 - 670 2000年 [査読有り]

　概要を見る

The Hard X-Ray Detector (HXD) is one of the instruments on board ASTRO-E, scheduled for lanch in January-February 2000. The HXD consists of 16 Well-type phoswich counters, surrounded by 20 active shield counters (Anti Coincidence Counters: Anti-Counters). It covers the energy range 10-600 keV with a very low background. Because the Anti-Counters are made of thich high-Z material with a very large geometrical area, they retain a large effective area up to high energies. Therefore the Anti-Counters can be used for monitoring high-energy transient sources and gamma-ray bursts. In this paper, the ail sky monitoring function with the Anti-Counters and the result of their ground calibration tests are described.
Variability pattern and the spectral evolution of the BL lacertae object PKS 2155-304

J Kataoka, T Takahashi, F Makino, S Inoue, GM Madejski, M Tashiro, CM Urry, H Kubo

ASTROPHYSICAL JOURNAL 528 ( 1 ) 243 - 253 2000年01月 [査読有り]

　概要を見る

The TeV blazar PKS 2155 - 304 was monitored with the X-ray satellite ASCA in 1994 May as part of a multiwavelength campaign from the radio to X-ray bands. At the beginning of the two-day continuous observation, we detected a lame flare, in which the 2-10 keV flux changed by a factor of 2 on a timescale of 3 x 10(4) s. During the hare, the increase in the hard X-ray flux clearly preceded that observed in the soft X-rays, with the spectral evolution tracking a "clockwise loop" in the flux versus photon index plane. Ascribing the energy-dependent variability to differential synchrotron cooling of relativistic electrons, we estimate the magnetic field B in the emission region. We tested two different methods of comparing the time series in various X-ray bands: (1) fitting the light curves to a Gaussian function and searching for the time shift of the peak of the flare, and (2) calculating the discrete correlation function. Both methods yielded a consistent solution of B similar to 0.1 G; We also found that the flare amplitude becomes larger as the photon energy increases, while the duration of the flare stays roughly constant throughout the ASCA energy band (0.7-7.5 keV). In the framework of the time-dependent synchrotron self-Compton model in a homogeneous region, we consider a flare where the maximum Lorentz factor (gamma(max)) of the injected electrons increases uniformly throughout the emission volume. The temporal evolution of spectra as well as the light curves were reproduced with the physical parameters self-consistently determined from seven observables. We obtained B similar to 0.1-0.2 G and a region size R similar to 10(-2) pc for relativistic beaming with a Doppler factor of delta similar to 20-30. We discuss the significance of light-travel time effects.
A study of high energy emission from the TeV blazar Mrk 501 during multiwavelength observations in 1996

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartmann, GM Madejski, P Sreekumar, SJ Wagner

BROAD BAND X-RAY SPECTRA OF COSMIC SOURCES 25 ( 3-4 ) 737 - 740 2000年 [査読有り]

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in March 1996 with ASCA. EGRET, Whipple, and optical telescopes. We report here for the first time the detection of GeV gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). Higher flux was also observed in April/May 1996, with 4.0 sigma for E > 100 MeV, and 5.2 sigma for E > 500 MeV. We find that the multiband spectrum in March 1996 is consistent with that calculated from a one-zone SSC model, except for the extremely 'flat' TeV spectrum. We show that this flat spectrum cannot be explained by either 2nd order Comptonization or the contribution of the 'seed' IR photons from the host galaxy. (C) 2000 COSPAR. Published by Elsevier Science Ltd.

DOI

Scopus
Thick and large area PIN diodes for hard X-ray astronomy

N Ota, T Murakami, M Sugizaki, H Kaneda, T Tamura, H Ozawa, T Kamae, K Makishima, T Takahashi, M Tashiro, Y Fukazawa, J Kataoka, K Yamaoka, S Kubo, C Tanihata, Y Uchiyama, K Matsuzaki, N Iyomoto, M Kokubun, T Nakazawa, A Kubota, T Mizuno, Y Matsumoto, N Isobe, Y Terada, M Sugiho, T Onishi, H Kubo, H Ikeda, M Nomachi, T Ohsugi, M Muramatsu, H Akahori

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 436 ( 1-2 ) 291 - 296 1999年10月 [査読有り]

　概要を見る

Thick and large area PIN diodes for the hard X-ray astronomy in the 10-60 keV range are developed. To cover this energy range in a room temperature and in a low background environment, Si PIN junction diodes of 2 mm in thickness with 2.5 cm(2) in effective area were developed, and will be used in the bottom of the Phoswich Hard X-ray Detector (HXD), on-board the ASTRO-E satellite. Problems related to a high purity Si and a thick depletion layer during our development and performance of the PIN diodes are presented in detail. (C) 1999 Elsevier Science B.V. All rights reserved.

DOI

Scopus

14

被引用数

(Scopus)
Multiwavelength observations of the TeV blazar Mrk 501 in March 1996. The first report of the detection by EGRET

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartman, GM Madejski, P Sreekumar, SJ Wagner

ASTROPARTICLE PHYSICS 11 ( 1-2 ) 149 - 151 1999年06月 [査読有り]

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in March 1996 with ASCA, EGRET, Whipple, and optical telescopes. We report here for the first time the detection of a GeV gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). A higher flux was also observed in April/May 1996, with 4.0 sigma significance for E > 100 MeV, and 5.2 sigma significance for E > 500 MeV. We find that the multiband spectrum in March 1996 is consistent with that calculated from a one-zone SSC model, except for the extremely 'flat' TeV spectrum. We show that the discrepancy cannot be explained by either second order Comptonization or the contribution of the 'seed' IR photons from the host galaxy. (C) 1999 Elsevier Science B.V. All rights reserved.

DOI

Scopus

14

被引用数

(Scopus)
Activation of the ASTRO-E hard x-ray detector in low earth orbit

M Kokubun, Y Fukazawa, E Idesawa, J Kataoka, T Kamae, K Matsuzaki, T Mizuno, Y Saito, T Takahashi, K Takizawa, M Tashiro, T Tamura, A Yoshida

IEEE TRANSACTIONS ON NUCLEAR SCIENCE 46 ( 3 ) 371 - 376 1999年06月 [査読有り]

　概要を見る

ASTRO-E Hard X-ray Detector (HXD) is characterized by well-type phoswich counters[1] in a compound-eye configuration which reduce the detector background to lower level than any other past hard X-ray mission. When operating in Low Earth Orbit, the expected background of the HXD is an order of 10(-5) counts/s/kev/cm(2), mainly caused from the radioactivity induced within the detector materials by geomagnetically trapped protons. Results are presented from measurements of induced radioactivity in two phoswich scintillators, GSO (Gd2SiO5:Ce 0.5% mol) and EGO (Bi4Ge3O12), irradiated by mono-energetic protons at an accelerator facility. Radiation transport computer codes are used to build the detector response functions for emissions from decays of spallation products. Based on the comparison between experimental and simulation results, the activation background level of HXD in the orbit is estimated.

DOI

Scopus

27

被引用数

(Scopus)
High-energy emission from the TeV blazar Markarian 501 during multiwavelength observations in 1996

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartman, GM Madejski, P Sreekumar, SJ Wagner

ASTROPHYSICAL JOURNAL 514 ( 1 ) 138 - 147 1999年03月 [査読有り]

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in 1996 March with ASCA, EGRET, Whipple, and optical telescopes. The X-ray flux observed with ASCA was 5 times higher than the quiescent level and gradually decreased by a factor of 2 during the observation in 1996 March. In the X-ray band, a spectral break was observed around 2 keV. We report here for the first time the detection of high-energy gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). Higher flux was also observed in 1996 April-May, with 4.0 sigma significance for E > 100 MeV and 5.2 sigma significance for E > 500 MeV. The gamma-ray spectrum was measured to be flatter than most of the gamma-ray blazars. We find that the multiband spectrum in 1996 is consistent with that calculated from a one-zone synchrotron self-Compton (SSC) model in which X-rays are produced via synchrotron emission and gamma-rays are produced via inverse Compton scattering of synchrotron photons in a homogeneous region. The flux of TeV gamma-rays is consistent with the predictions of the model if the decrease of the Compton scattering cross section in the Klein-Nishina regime is considered. In the context of this model, we investigate the values of the magnetic field strength and the beaming factor allowed by the observational results. We compare the 1996 March multiwavelength spectrum with that in the flare state in 1997 April. Between these two epochs, the TeV flux increase is well correlated with that observed in keV range. The keV and TeV amplitudes during the 1997 April hare are accurately reproduced by a one-zone SSC model, assuming that the population of synchrotron photons in 1996 are scattered by newly injected relativistic electrons having maximum energies of gamma(max) similar to 6 x 10(6). However, the TeV spectrum observed during the 1996 March campaign is flatter than predicted by our models. We find that this cannot be explained by either higher order Comptonization or the contribution of the "seed" IR photons from the host galaxy for the first-order external radiation. Comptonization, but we cannot exclude possible effects of the IR photons that may arise in the parsec-size tori postulated to exist in active galactic nuclei.
Variability pattern and the spectral evolution of blazars

J. Kataoka

Astronomische Nachrichten 320 ( 4-5 ) 309 1999年

　概要を見る

The rapid, large-amplitude variability and very wide spectral energy distribution are marked features of blazars. To investigate the nature of these extreme particle accelerators, a number of multi-frequency campaigns have been conducted so far. Recent campaigns of the TeV blazars, Mrk 421 and Mrk 501, revealed a correlated flare between the keV X-ray and TeV γ-ray bands, providing valuable information for the emission mechanism of blazars. However, theoretical efforts lag behind the observations. Most of the previous works consider only the steady state emission, in spite of rapid blazars' variability. To understand the time evolution of blazar spectra quantitatively, we developed a time-dependent model based on the synchrotron self-Compton (SSC) emission in a homogeneous region, incorporating the radiative cooling and acceleration process properly. In this paper, we apply this model to the X-ray flare of PKS 2155-304 observed in 1994. We obtained the satisfactory fit for both spectra and light curves with the magnetic field B ∼ 0.1 - 0.2 G and the region size R ∼ 10-2 pc, assuming a Doppler beaming factor of δ ∼ 20 - 30.

DOI

Scopus
Activation of the ASTRO-E hard X-ray detector in low Earth orbit

Kokubun M, Fukazawa Y, Idesawa E, Kataoka J, Kamae T, Matsuzaki K, Mizuno T, Saito Y, Takahashi T, Takizawa K, Tashiro M, Tamura T, Yoshida A

IEEE Nuclear Science Symposium and Medical Imaging Conference 1 227 - 232 1999年 [査読有り]
Electronic system for the Astro-E Hard X-ray Detector

T. Takahashi, M. Nomachi, Y. Fukazawa, M. Tashiro, H. Ezawa, M. Hamaya, M. Horii, N. Isobe, N. Iyomoto, J. Kataoka, T. Kamae, G. Kawaguchi, H. Kubo, S. Kubo, A. Kubota

Proceedings of SPIE - The International Society for Optical Engineering 3445 155 - 168 1998年 [査読有り]

　概要を見る

Hard X-ray Detector (HXD) is one of three instruments on the fifth Japanese X-ray astronomy satellite, Astro-E, scheduled for launch in 2000. The sensitivity of the Astro-E HXD will be higher by more than one order of magnitude than that of any previous instrument between 10 keV and several 100 keV. The electronic system is designed to handle many independent data channels from the HXD within the limitation of size and power consumption required in Astro-E. In this paper, we will present the design and the preliminary performance of the processing electronic system.
Verification of the Astro-E Hard X-ray Detector based on newly developed Ground Support Equipment

J Kataoka, M Nomachi, T Takahashi, G Kawaguchi, Y Terada, T Murakami, C Tanihata, Y Uchiyama, K Yamaoka, Y Fukazawa, T Kamae, K Makishima, M Tashiro, H Kubo

EUV, X-RAY, AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY IX 3445 143 - 154 1998年 [査読有り]

　概要を見る

We report the first results of the ground test of the Hard X-ray Detector (HXD) on board the Astro-E mission, by means of the newly developed Ground Support Equipment (GSE). Astro-E will be launched in 2000 by a Japanese M-V rocket. In order to verify the detector system during the limited time before launch, fast and versatile GSE is necessary. For this, we have developed a flexible test system based on nine VME I/O boards for a SUN workstation. These boards carry reconfigurable Field Programmable Gate Arrays (FPGAs) with 50,000 gates, together with 1 Mbyte SRAM devices tightly coupled to each FPGA device. As an application of using this GSE, we have tested the performance of a phoswich unit of the Flight Model of the HXD. In this paper, we present a schematic view of the GSE highlighting the functional design, and the results of our ground test of the HXD-sensor under the high count rate environment (similar to 10 kHz/unit) expected in orbit.
Integration of the readout electronics for the ASTRO-E hard X-ray detector

H. Ozawa, J. Kataoka, T. Murakami, M. Sugizaki, T. Takahashi, K. Yamaoka, H. Ezawa, Y. Fukazawa, T. Kamae, K. Makishima, T. Mizuno, K. Nakazawa, S. Osone, H. Ikeda, K. Tsukada, H. Kubo

Proceedings of SPIE - The International Society for Optical Engineering 3115 235 - 243 1997年 [査読有り]

　概要を見る

We have developed the analog electronics of the ASTRO-E Hard X-ray Detector (HXD). The ASTRO-E is the fifth Japanese X-ray astronomy satellite scheduled for launch in 2000. Three experiments will be on board the satellite, one of which being the HXD. The detector consists of 16 units of well-type phoswich counters with silicon PIN diodes embedded therein, and covers the energy range of 10 ∼ 600 keV with photon collecting area of about 350 cm2. The readout circuit for the HXD handles many signal channels (96 channels in total) under the limitation of power consumption and size set by the satellite. To meet the limitations, we have developed two types of bipolar semicustom LSIs. One is the pulse-shape discriminator (PSD-LSI) for phoswich counters and the other is for silicon PIN diodes (PIN-LSI). The PSD-LSI selects clean GSO hits and reduces the off-aperture X-rays and internal background of the detector down to 10-5 c/s/cm2/keV. One PIN-LSI handles signals from two PIN diodes, each consisting of an amplifier, a peak-hold circuit, and a comparator to trigger the readout system. Test pieces of these LSIs meet the specifications such as power consumptions and linearities. Using PIN-LSI, we could successfully obtain X-ray spectrum from 241Am with a PIN diode.

DOI J-GLOBAL

Scopus

7

被引用数

(Scopus)
Development of the hard X-ray detector for the ASTRO-E mission

T Takahashi, H Ezawa, Y Fukazawa, M Hirayama, E Idesawa, H Ikeda, Y Ishisaki, N Iyomoto, T Kamae, J Kataoka, H Kaneda, H Kubo, K Makishima, K Matsushita, K Matsuzaki, T Mizuno, T Murakami, K Nagata, S Nakamae, M Nomachi, H Obayashi, T Ohtsuka, H Ozawa, Y Saito, M Sugizaki, T Tamura, M Tashiro, N Tsuchida, K Tsukada, A Yoshida

ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES 120 ( 4 ) C645 - C648 1996年12月 [査読有り]

　概要を見る

The Hard X-ray Detector (HXD) is one of three instruments on the fifth Japanese X-ray astronomy satellite, ASTRO-E, scheduled for launch in 2000. The HXD consists of a 4x4 = 16 modular assembly of identical counters, each consisting of a combination of YAP(or GSO)/BGO well-type phoswich counters and silicon PIN diodes. The field of view of the detector for high energy photons is restricted to 4 degrees x 4 degrees by active collimators made of BGO and the fov for low energy photons is restricted to 0.5 degrees x 0.5 degrees by the fine passive collimators made of phosphor bronze. The detector is characterized by a low background reaching severalx10(-6) c/s/cm(2)/keV. Combined with the other two instruments for soft X-ray observations (0.5-12 keV), the ASTRO-E mission will cover the entire range of soft and hard X-rays with the highest sensitivity ever achieved. Furthermore, thick EGO counters which surround the 4x4 matrix of well-type phoswich counters act as a gamma-ray burst detector in the energy band of 100-2000 keV.
ASCA observation of an X-ray/TeV flare from the BL Lacertae object Markarian 421

T Takahashi, M Tashiro, G Madejski, H Kubo, T Kamae, J Kataoka, T Kii, F Makino, K Makishima, N Yamasaki

ASTROPHYSICAL JOURNAL 470 ( 2 ) L89 - L92 1996年10月 [査読有り]

　概要を見る

We observed the BL Lac object Mrk 421 with the X-ray satellite ASCA in 1994 as part of a multifrequency observation. The 24 hr observation was conducted 1 day after the onset of a TeV flare detected by the Whipple Observatory and detected an X-ray flare, with no apparent variability in the optical, UV, and EGRET GeV flux. The ASCA 2-10 keV flux peaked at 3.7 x 10(-10) ergs cm(-2) s(-1) and then decreased to 1.8 x 10(-10) ergs cm(-2) s(-1) with a doubling timescale of similar to 12 hr. The shape of the X-ray spectrum varied during the observation, such that the hard X-rays always led the soft X-rays, both in brightening and dimming of the source, with a lag of the 0.5-1 keV photons versus those in the 2-7.5 keV band of similar to 1 hr. The rapid TeV variability indicates a compact TeV-producing region, suggesting relativistic beaming with a Doppler factor delta greater than or equal to 5. The correlation of the flux in the X-ray and the TeV bands indicates that a high-energy tail of a single electron population is responsible for both X-rays and TeV gamma-rays, with radio, IR, UV and X-rays produced via the synchrotron process and GeV and TeV gamma-rays produced via Comptonization. Under the assumption that the ''soft lag'' observed in the X-ray band is due to the synchrotron-lifetime effects, with delta = 5, we calculate the magnetic field for the X-ray-producing region to be similar to 0.2 G. The Lorentz factors gamma(el) of the electrons responsible for the emission in the keV and TeV bands are similar to 10(6), consistent with the values implied by the Klein-Nishina limit.
Gamma-ray burst monitoring with the hard X-ray detector onboard the ASTRO-E mission

A Yoshida, H Ezawa, Y Fukazawa, M Hirayama, E Idesawa, H Ikeda, Y Ishisaki, N Iyomoto, T Kamae, J Kataoka, H Kaneda, H Kubo, K Makishima, K Matsushita, K Matsuzaki, T Mizuno, T Murakami, K Nagata, S Nakamae, M Nomachi, H Obayashi, T Otsuka, H Ozawa, Y Saito, M Sugizaki, T Takahashi, T Tamura, M Tashiro, N Tsuchida, K Tsukada

GAMMA-RAY BURSTS - 3RD HUNTSVILLE SYMPOSIUM, PTS 1 AND 2 ( 384 ) 870 - 874 1996年 [査読有り]

　概要を見る

ASTRO-E is the fifth Japanese X-ray astronomy satellite scheduled to be launched in year 2000. The satellite will carry three scientific instruments, one of which is the Hard X-ray Detector (HXD). HXD will cover the 10-600 keV band with low background of several x 10(-6)c/s/cm(2)/keV. This will be achieved by the well-type phoswich counter technique together with large active shield counters of EGO (about 1200 cm(2)/side), which are also capable to detect GRBs in the 100-2000 keV band. About 100 GRBs are expected to be detected per year with HXD.
ASCA Observations of X-ray/TeV Flare from Mkn 421

Takahashi et a

Mem. Della Soc.Astr. Ital. 67 533 1996年
A SEARCH FOR MASSIVE NEUTRAL BOSONS IN ORTHOPOSITRONIUM DECAY

T MAENO, M FUJIKAWA, J KATAOKA, Y NISHIHARA, S ORITO, K SHIGEKUNI, Y WATANABE

PHYSICS LETTERS B 351 ( 4 ) 574 - 578 1995年06月 [査読有り]

　概要を見る

We have searched for an exotic decay of orthopositronium into a single photon and a short-lived neutral boson in the hitherto unexplored mass region above 900 keV/c(2), by noting that this decay is one of few remaining candidates which could explain the discrepancy of the orthopositronium decay rate. A high-resolution measurement of the associated photon energy spectrum was carried out with a germanium detector to search for a sharp peak from this two-body decay. Our negative result provides an upper limit of 2.0 x 10(-4) on the branching ratio of such a decay in the mass region from 847 to 1013 keV/c(2), and excludes the possibility of this decay mode explaining the discrepancy in the orthopositronium decay rate.

DOI

Scopus

19

被引用数

(Scopus)

▼全件表示

書籍等出版物

薬物動態を可視化する放射化イメージング：宇宙の元素合成を医療に応用

越川七星, 片岡淳( 担当：共著)

月刊化学（化学同人） 2023年05月
広帯域 X 線・ガンマ線による薬剤可視化へ向けた新技術

越川七星, 増渕美穂, 片岡淳( 担当：共著)

応用物理学会放射線分科会会誌 vol.48 2023年04月
CT開発の最先端 Photon-Counting CT

有元誠, 川嶋広貴, 小林聡, 片岡淳( 担当：共著)

日獨医報 vol.66、No.1 2022年07月
コンプトンカメラを用いたアクティブ動態イメージング

片岡淳, 小俣陽久, 増渕美穂, 越川七星( 担当：共著)

Medical Imaging Technology, vol.39、No.5 2021年11月
Spectral Photon-Counting CT System Based on Si-PM Coupled with Novel Ceramic Scintillators

H.Kiji, T.Toyoda, J.Kataoka, M.Arimoto, S.Terazawa, S.Shiota, H.Ikeda( 担当：共著)

Radiation Detection Systems – Medical Imaging, Industrial Testing and Security Applications, CRC press 2021年04月 ISBN: 9781003218364
Activity bubbling up

Jun Kataoka( 担当：単著)

Nature Astronomy 2020年10月
宇宙物理学ハンドブック（朝倉書店）

高原文郎, 家正則, 小玉英雄, 高橋忠幸, 集( 担当：分担執筆)

2020年02月 ISBN: 9784254131277

▼全件表示

講演・口頭発表等

放射化を用いた薬物動態可視化への挑戦

片岡淳 [招待有り]

日本放射化学会第68回討論会

発表年月： 2024年09月
これからの核医学・粒子線治療に向けた放射線イメージング

片岡淳 [招待有り]

第127回日本医学物理学会学術大会

発表年月： 2024年04月

開催年月：
2024年04月

　

　
東工大における小型衛星とセンサー開発:2001-2008

片岡淳 [招待有り]

東京工業大学研究会

発表年月： 2023年03月
ガンマ線イメージングが拓く近未来：宇宙から医療・大気・資源探査へ

片岡淳 [招待有り]

第83回応用物理学会秋季年会（2022）

発表年月： 2022年09月
X線ガンマ線イメージングでつなぐ宇宙と医療

片岡淳 [招待有り]

日本コンピュータ外科学会大会

発表年月： 2022年06月
X線ガンマ線イメージングが切り拓く近未来 - 宇宙物理と放射線治療の架け橋へ -

片岡淳 [招待有り]

日本医学物理学会学術大会

発表年月： 2022年04月
X線ガンマ線イメージングの医療応用

片岡淳 [招待有り]

原子・分子・光科学(AMO)討論会

発表年月： 2021年06月
医療革新に向けた診断装置スペクトラルCTの開発

片岡淳 [招待有り]

筑波会議

発表年月： 2019年10月
核医学や高精度陽子線治療にむけたイメージング装置の開発

片岡淳 [招待有り]

放射線基礎セミナーアイソトープ協会

発表年月： 2018年07月
宇宙から医療まで:放射線イメージングの最前線

片岡淳 [招待有り]

第65回応用物理学会・特別シンポジウム応用物理学会

発表年月： 2018年03月
“手のひらサイズ”コンプトンカメラを用いた3D in vivo イメージングへの挑戦

片岡淳 [招待有り]

第13回小動物インビボイメージング研究会日本核医学会

発表年月： 2017年07月
X-ray Observations of the Fermi Bubbles and Loop-I Structures

Jun Kataoka [招待有り]

Roaming Baryons in the Universe

発表年月： 2017年07月
MPPC-based scintillation detectors for innovative X-ray and gamma-ray imaging

片岡淳 [招待有り]

第64回応用物理学会・シンポジウム応用物理学会

発表年月： 2017年03月
MPPC を用いた放射線イメージングの最前線－宇宙・環境・医療のクロスオーバー

片岡淳 [招待有り]

山形大学理学部セミナー

発表年月： 2016年07月
次世代放射線イメージングに向けたSi-PMシンチレーション検出器

片岡淳 [招待有り]

EMN2016 - Photodetectors' Meeting (カンクン、メキシコ)

発表年月： 2016年06月
High Energy Emission from the GC and Fermi Bubble

片岡淳 [招待有り]

山口大学セミナー

発表年月： 2015年07月
高エネルギーX線・ガンマ線でみた活動銀河ジェットの観測的特徴

[招待有り]

国際天文学連合シンポジウム 313

発表年月： 2014年09月
次世代半導体光素子MPPCを用いた高精度X線・ガンマ線イメージング

[招待有り]

Symposium on Radiation Measurements and Applications (SORMA XV 2014) (ミシガン、アメリカ)

発表年月： 2014年06月
すざく衛星による、フェルミバブル境界からの広がったX線放射の観測

[招待有り]

66th Fujiwara seminar: X-raying the Gamma-ray universe – CTA X-ray Link Meeting

発表年月： 2013年11月
フェルミ・バブルのX線観測とレビュー

[招待有り]

The Fermi Bubbles: Theory and Observations

発表年月： 2013年04月
フェルミ衛星時代における活動銀河核の観測

[招待有り]

Fermi Symposium 2012

発表年月： 2012年10月
Astro-H衛星搭載APD検出器の放射線損傷について

IEEE Nuclear Science Symposium and Medical Imaging

発表年月： 2012年10月
Fermi宇宙ガンマ線望遠鏡によるAGNおよび未同定天体の観測：最近の進展

[招待有り]

3rd Fermi Asian Network (FAN3)

発表年月： 2012年06月
3次元位置有感型シンチレータを用いた携帯型コンプトンカメラの開発

Vienna Conference on Instrumentation 2013 (VCI2013)

発表年月： 2012年02月
Fermi宇宙ガンマ線望遠鏡によるAGN観測と統一描像

[招待有り]

2nd Fermi Asian Network (FAN2)

発表年月： 2011年08月
Fermi宇宙ガンマ線冒険教による広輝線電波銀河の観測：ジェットと降着円盤スペクトルの縮退を解く

Fermi Symposium 2011

発表年月： 2011年05月
大面積APDアレーの開発と次世代PET技術への展望

[招待有り]

日本応用物理学会春季年会

発表年月： 2009年03月
「純国産」APD-PETの実用化にむけて

[招待有り]

H20 次世代PET研究会

発表年月： 2009年01月
Chandra Reveals Twin X-ray Jets in the Powerful FR II Radio Galaxy 3C 353

International Symposium on High Energy Gamma-ray Astronomy

発表年月： 2008年07月
Chandra Reveals Twin X-ray Jets in the Powerful FR II Radio Galaxy 3C 353

[招待有り]

Workshop on Blazar Variability across the Electromagnetic Spectrum

発表年月： 2008年04月
High Energy Observations of AGN Jets and Their Future Prospects

[招待有り]

Accelerators in the Universe

発表年月： 2008年03月
Suzaku View of Powerful Gamma-ray Quasars and TeV Blazars

[招待有り]

The Suzaku X-ray Universe

発表年月： 2007年12月
High Energy Observations of AGN Jets and their Implications

[招待有り]

High Energy Observations of AGN Jets and their Implications

発表年月： 2007年12月
多波長観測から探るジェットの加速・輸送・組成について

[招待有り]

3 学会合同プラズマ共催セッション特別講演

発表年月： 2007年09月
Suzaku View of Powerful Gamma-ray Quasars

[招待有り]

High Energy Gamma-rays from Relativistic Outflows

発表年月： 2007年09月
APD-PET へむけた開発の現状

[招待有り]

H19 次世代PET 研究会

発表年月： 2007年07月
ジェットの本質的理解にむけて；最近の話題から

[招待有り]

VSOP2 グループセミナー

発表年月： 2007年06月
活動銀河ジェットの粒子加速とエネルギー輸送・内部組成について

[招待有り]

東北大学天文学教室談話会

発表年月： 2007年04月
Suzaku Observarion of AGN and Synnergy with GLAST

[招待有り]

First GLAST Symposium

発表年月： 2007年02月
APD 開発の現状と今後

[招待有り]

次世代PET 研究会

発表年月： 2007年01月
APD に関する研究紹介とPET 利用への道のり

[招待有り]

放射線医学研究所定例セミナー

発表年月： 2006年12月
APD 開発の現状—宇宙利用から高速PET まで

[招待有り]

第２回次世代光センサーワークショップ

発表年月： 2006年12月
Broad-Band Emission of Large-Scale Jets in AGNs

[招待有り]

Challenges of Relativistic Jets

発表年月： 2006年06月
Acceleration and Non-thermal Phenomena in AGN jets

[招待有り]

High Energy Astrophysics in the NeXT Decade

発表年月： 2006年06月
活動銀河核ジェットの物理：観測からの制限

[招待有り]

早稲田大学理論宇宙研セミナー

発表年月： 2006年06月
Suzaku 衛星によるAGN の観測と将来展望

[招待有り]

高エネルギーガンマ線天文学の展望

発表年月： 2006年03月
宇宙の一番星ガンマ線バースト偏光Ｘ線観測衛星の提案

[招待有り]

「れいめい」成果報告会 JAXA 宇宙科学研究本部

発表年月： 2005年11月
TeV ブレーザーの多波長観測から探る、相対論的ジェットの物理

[招待有り]

東海大学理学部セミナー

発表年月： 2005年11月
What can GLAST tell us about AGN jets?

[招待有り]

GLAST Science Workshop

発表年月： 2005年11月
相対論的ジェットにおける粒子加速とエネルギー輸送の研究

[招待有り]

日本天文学会研究奨励賞受賞講演

発表年月： 2005年03月
X-ray Emission Properties of Relativistic Jets in AGN

[招待有り]

International Workshop on Magnetohydrodynamic (MHD) Accretion Flow and Jets

発表年月： 2005年01月
X 線観測とVSOP-2 で切り開く活動銀河核ジェットの物理

[招待有り]

VSOP2 サイエンスワークショップ

発表年月： 2004年12月
大規模ジェットはどこまで理解できたか？電波・X 線観測の総まとめ

AGN ジェット放射機構と高エネルギー粒子の加速機構

発表年月： 2004年11月
宇宙用アバランシェフォトダイオードの開発：衛星搭載と撮像への応用

[招待有り]

JAXA (つくば) 定例講演会

発表年月： 2004年02月
大学規模での衛星開発；東工大の挑戦

[招待有り]

第４回宇宙科学シンポジウム

発表年月： 2004年01月
AGN ジェットにおける加速とエネルギー輸送: sub-pc からkpc まで

[招待有り]

CANGAROO 望遠鏡によるガンマ線天文学の新展開

発表年月： 2003年12月
Chandra Observation of kpc-Scale Jets: Sites of Extreme Particle Acceleration

[招待有り]

Japan-Korea Workshop

発表年月： 2003年03月
X-ray and Gamma-ray Observations of Blazars; Recent Progress and Future Perspectives

[招待有り]

GLAST collaboration meeting

発表年月： 2002年10月
活動銀河ジェットの粒子加速：ブラックホールからホットスポットまで

[招待有り]

ガンマ線バースト研究会

発表年月： 2002年08月
激動する宇宙：Ｘ線・ガンマ線天文学最前線

[招待有り]

高校生のための物理公開講座

発表年月： 2002年07月
Multiwavelength Observations of Blazars and the Implications on Particle Acceleration in Jets

[招待有り]

Invited Seminar, Perugia University, Italy

発表年月： 2002年06月
X-ray Study of Rapid Variability in TeV Blazars and Implications on Particle Acceleration in Jets

[招待有り]

宇宙線物理学奨励賞受賞講演

発表年月： 2002年03月
活動銀河からの高エネルギー放射：観測と理論のアプローチ

[招待有り]

立教大学理学部セミナー

発表年月： 2001年09月
宇宙における巨大加速器：活動銀河核ジェットはどこまで分かったか？

[招待有り]

2001 天文若手夏の学校

発表年月： 2001年08月
Characteristic Variability in Blazars: Clues to Jet Physics

[招待有り]

GLAST collaboration meeting

発表年月： 2001年08月
2001 天文若手夏の学校

[招待有り]

ディスクとジェット研究会

発表年月： 2001年03月
活動銀河核からの高エネルギー放射]相対論的ジェットの物理

[招待有り]

宇宙放射線研究室セミナー理化学研究所

発表年月： 2001年02月
TeV ブレーザーの多波長同時観測と時間変動の統一描像

[招待有り]

ディスクとジェット研究会

発表年月： 2000年03月
ガンマ線ブレーザーの他波長同時観測と時間変動の統一描像

[招待有り]

第２回ぐんま天文台における天体物理学

発表年月： 2000年02月
X-ray Study of Rapid Variability in TeV Blazars and the Implication on Particle Acceleration in Jets

[招待有り]

Japan-Germany Symposium

発表年月： 1999年11月

▼全件表示

研究シーズ

高感度DOI-PET検出器

ライフサイエンス
高感度DOI-PET検出器

ライフサイエンス

共同研究・競争的資金等の研究課題

細胞から組織、臓器へ：α線治療薬At-211の微視的・巨視的動態イメージング

日本学術振興会科学研究費助成事業

研究期間:

2024年04月

-

2027年03月

片岡淳
ERATO 片岡ラインX線ガンマ線イメージングプロジェクト

ERATO

研究期間:

2021年10月

-

2027年03月

片岡淳
治療・診断統合による次世代ドラッグデリバリー可視化システムの実証

日本学術振興会科学研究費助成事業

研究期間:

2020年04月

-

2023年03月

片岡淳, 加藤弘樹, 上田真史

　概要を見る

近年、抗がん剤など治療薬を空間・時間的に制御し、病巣にピンポイントで届けるドラッグデリバリーシステム（以下、DDS）の開発が目覚ましい。一方で、薬剤が正しく病巣に届けられ、狙ったタイミングで放出されたかを「その場で・簡単に」可視化する術がない。本研究では次世代医療の鍵となる3つの薬剤、すなわち①抗がん剤 ②治療用放射性(RI)薬剤 ③ホウ素薬剤に着目し、革新的DDS可視化技術の実現と、これに必要な創薬をあわせて実施する。診断と治療の「見える化」により、安全・安心な医療の新しい未来を創出する
X線CTの超鮮鋭化による医療診断の新展開

日本学術振興会科学研究費助成事業

研究期間:

2019年04月

-

2023年03月

有元誠, 小林聡, 片岡淳

　概要を見る

X線CTは非破壊的に人体内部構造を3次元的に取得でき、このX線CTでしか見つからない病変が多く、現代医療を支える上で必須の技術である。微細な血管を鮮明に映し出すために造影剤が用いられることが多いが、患者の病気によっては、造影剤の使用を大きく制限されることがあり未だ安全で汎用な技術には至っていない。この課題を克服するためには、X線CT装置の圧倒的な感度向上が必須となる。本研究では、これを実現するために次世代光センサーMPPCを用いた超高感度のX線CT技術を新たに創出し、かつ臨床的見地からの性能実証を目指す。そして、高感度化の実現により新しい診断医療の道を切り開くアプローチへの足がかりとする
超解像を用いた革新的ガンマ線イメージング技術の創成

日本学術振興会科学研究費助成事業

研究期間:

2020年07月

-

2022年03月

片岡淳

　概要を見る

一般に高エネルギー実験や核医学で得られる画像は統計との闘いであり、解像度も十分ではない。とくに、ガンマ線は可視光のように集光できず、光子１つ１つを検出する特殊な技術が必要なため、画像処理でも大きな後れを取っている。本研究では10 keVから10 GeV のガンマ線画像で広く適用可能なスパースコーディング技術を開発し、医療・天文分野の新たな革新を狙う
粒子線治療中の2次被ばく低減に向けた中性子可視化への挑戦

日本学術振興会科学研究費助成事業

研究期間:

2017年06月

-

2020年03月

片岡淳

　概要を見る

本年度は最終年度であり、これまで開発したすべての要素技術を組み合わせ最適構成の中性子カメラを完成した。装置は 16ユニットのn/γ波形弁別型シンチレータEJ299-34およびウルトラバイアルカリ小型PMT(R9880-210U)から構成され、Geant4シミュレーションにより前段・後段の配置とパラメータを最適化した。各PMTの信号は1GHzクロックによる高速波形サンプリング16chシステムで取得し、PSD弁別(Pulse Shape Discrimination)によりn/γ弁別を行う。続いて前段・後段のトリガタイミングから TOF(Time-of-Flight)分布を取得し、MeV 以下のエネルギーをもつ中性子のみを効率よく選別する。まず実験室において252^Cf を用いた実測で各種調整を行い、期待される性能を確認した。続いて放医研サイクロトロン施設でコリメータを模した真鍮ファントムに70MeV、100pAの陽子線ビームを打ちこみ、そこから発生する二次中性子を撮影した。PSD/TOF 弁別で膨大なガンマ線バックグラウンドを除去することに成功し、MRP-EM法(iteration回数 40)で画像再構成を試みた。線源方向を0°,15°, 30°としたときの再現性は 0.48±1.26°,15.2±0.6°,28.5±0.8°が得られ、解像度は15°(FWHM)程度が得られた。さらに、得られた中性子スペクトルから真鍮ファントムにおける陽子線の吸収線量を概算することに成功した。概ね予定通りの性能をもつ装置が完成したが、今後は陽子線治療施設で 100MeV, 1-10 nA 程度の陽子線ビーム照射時に同様なイメージング実験を行い、最終確認としたい。本成果は6月開催の国際会議 NDIP2020で発表予定であったが、COVID-19の影響で会議自体が延期となったのは残念である。令和元年度が最終年度であるため、記入しない。令和元年度が最終年度であるため、記入しない
実用化へ向けた高解像度3Dカラー放射線イメージング技術の開拓

日本学術振興会科学研究費助成事業

研究期間:

2015年05月

-

2020年03月

片岡淳, 松永恵子, 畑澤順

　概要を見る

本年度は最終年度にふさわしく、これまでの研究を統括する重要な成果が得られた。まず、低被ばく多色X線CTに関しては、64chを同時に測定する新規システムを構築した (Maruhashi et al.2020)。光センサーであるMPPCは信号レートが高い状況で発熱し、ゲインが低下する問題があった。本年度は熱特性に優れたセラミックMPPCアレイおよび高速シンチレータを新規に開発し、耐レート特性の向上とCT画像CNR(contrast to noise ratio)の大幅な改善を確認した。さらに、抗がん剤として着目される金ナノ粒子(Au-NP）と造影剤（ヨード・ガドリニウム）の同時撮影に成功し、CT装置を薬剤動態モニターとして使う新たな可能性を示した。続いて核医学治療（塩化ラジウムを用いたアルファ線内用療法）では、阪大病院において前立腺がん患者2名を対象にコンプトンカメラによる臨床試験を実施した。本年度は人体撮影を目的とした10×10cm^2の大型カメラを新規に製作し、10分間の撮影で体の広範囲の薬剤分布を精確に可視化することに成功した。コンプトンカメラの核医学治療への応用としては世界初の成果となる (Fujieda et al. 2020)。最後に、ガンマ線可視化技術の要望は粒子線治療分野でも次第に高まりつつある。本研究では、次世代陽子線治療である陽子ホウ素捕獲療法(pBCT)について、その実現性についても検討した。具体的には、p+11^B → 3α反応、および関連するアルファ線生成反応が起こす線量への寄与について、CCD カメラによる可視化とゲルマニウム半導体を用いた詳細スペクトル測定、さらに核反応断面積の導出に挑戦した。シミュレーションや理論計算のみで実施されてきたpBCT に初めて実験的なメスを入れる画期的な検証を行うことができた。令和元年度が最終年度であるため、記入しない。令和元年度が最終年度であるため、記入しない
医療応用を目指した3Dカラー放射線イメージングの新展開

研究期間:

2015年04月

-

2019年03月
放射性セシウムの土壌沈着深さがわかるガンマ線カメラの開発

日本学術振興会科学研究費助成事業

研究期間:

2015年04月

-

2017年03月

片岡淳

　概要を見る

本研究では、福島原発事故で飛散した137-Cs分布の3次元可視化技術を新たに開拓した。具体的には(1)土壌中で散乱した2次ガンマ線と直接ガンマ線の比率 (2)散乱ガンマ線画像の広がりの両方を用いることで、2次元ガンマ線画像の縮退を解くことができる。シミュレーション及び実験室環境での詳細検証を経て、福島県浪江の森林部においてフィールド試験を行った。137-Csが深度方向に指数関数分布をしていると仮定し、緩衝深度β=2.22±0.05 cmを得た。これはスクレーパープレートによる直接調査の結果と良く一致している。今後は SPECT などで散乱ガンマ線を用いることで、新たな医療応用も期待できる
半導体光増幅素子を用いた革新的次世代ＰＥＴ技術の開発実証

研究期間:

2010年05月

-

2015年03月

　概要を見る

本研究では癌の早期発見を目指し、半導体光センサーMPPCを基盤とした3つの次世代PET技術の開発を行なった。まず、ガンマ線の反応位置を3次元かつ1mm以下の精度で決める新規技術を開発し、小動物用PET装置を用いて視野端まで歪みのない高解像度(約1mm)を得ることに成功した。続いて小型のMRI併用PET装置を製作し、4.7テスラの強磁場中でPET/MRI双方の画像に影響が無いことを実証した。さらにMPPC専用の高速LSIを2種類独自に開発し、ガンマ線の飛行時間差を用いたTOF-PET技術を開拓した。単素子では213ピコ秒、16chアレイでも489ピコ秒(FWHM)の優れた性能が得られた
爆発的X線・γ線から探るガンマ線バーストの起源と環境

日本学術振興会科学研究費助成事業

研究期間:

2007年

-

2010年

河合誠之, 吉田篤正, 山岡和貴, 村上敏夫, 藤本龍一, 冨田洋, 片岡淳

　概要を見る

本研究の目的は、ガンマ線バースト(GRB)の位置の迅速・正確に決定して速やかな残光観測に結びつけることと、X線・γ線放射の詳細観測からGRBの起源と環境を探ることである。そのため、X線全天監視装置MAXIの開発を進め、GRBの検出・通報に成功した。また、将来のミッションのためのX線分光器とGRB位置検出器の基礎開発を進めた。さらに、HETE-2、Fermi、Suzakuなどの人工衛星による観測データの解析を進め、ピークエネルギーと光度の相関関係、X線・γ線放射光度曲線のエネルギー依存性などを明らかにした
大学主導による高速駆動衛星の開発と突発天体のγ線偏光観測実証

日本学術振興会科学研究費助成事業

研究期間:

2007年

-

2009年

片岡淳, 松永三郎, 河合誠之, 河合誠之

　概要を見る

小型衛星を用いた突発天体からのX線・ガンマ線偏光観測に向け、東工大で開発する50kg級小型衛星「つばめ」に搭載する観測装置(硬X線偏光検出器、バースト位置検出器)および高速姿勢制御装置の試作開発を行った。詳細なシミュレーションと実機(エンジニアリングモデル)による評価・試験から、目的とした観測性能をすべて達成できることを示した。大型衛星では困難な「小回りの良さ」と「最先端の観測機器」を駆使した小型衛星の新しいアプローチ、また小型衛星を用いた新しいサイエンスの方向性を示すことができた
小型大学衛星の開発

研究期間:

2001年

-

2009年
Fermi衛星を用いたガンマ線宇宙物理学（スタンフォード大学他）

研究期間:

2008年

-

　
広がった天体の加速メカニズム解明に向けたX線画像復元法と偏光測定法の開発

日本学術振興会科学研究費助成事業

研究期間:

2006年

-

2008年

釜江常好, 牧島一夫, 片岡淳, 水野恒史, 牧島一夫, 片岡淳, 水野恒史

　概要を見る

「すざく」X線反射鏡の画像歪み修復するプログラムを開発するとともに、日本の次期X 線観測衛星で使われる予定のX線ミラーが生む人工的偏光の上限を実測した。また気球を使って「かに」星雲やブラックホール天体白鳥座X-1から観測される硬X線の偏光を測定する装置、PoGOLiteを開発した。画像修復のプログラムの成果は、Sugizaki, Kamae, Okajima, PASJ 61S (2009) 55、PoGOLiteの偏光観測装置は、Kamae et al.Astroparticle Phys.30 (2008) 72、ミラーが生む人工的変更については、Katsuta et al., Nuclear Instr.Meth.A, 603 (2009) 393で発表した
先端的宇宙技術の早期実証を可能にする超小型衛星システムの開発と軌道上運用

日本学術振興会科学研究費助成事業

研究期間:

2004年

-

2006年

松永三郎, 中須賀真一, 片岡淳

　概要を見る

本研究では、超小型衛星用分離機構1の軌道上実証システムの開発を行い、2005年7月にM-V-6号機にて打ち上げ実験を行い成功した。並行して、超小型衛星Cute-1.7+APDを提案して、PDAなどの民生品を用いた衛星バス機器、APD、磁気トルカを用いた姿勢制御、超小型テザー伸展機構の軌道上実証を目指した。本衛星はM-V-8号機により、2006年2月に打ち上げに成功し、約1ヶ月の運用を行った。さらに、この運用を通して得られた様々な知見を生かして大幅に改良設計を施したCute-1.7+APDIIの開発を進め、独自開発した太陽センサ、磁気センサ、ジャイロ、小型カメラ画像、磁気トルカを統合した姿勢制御シミュレータの開発を行った。さらに、優れた低ノイズ特性を持つAPDを開発し、ゲインの自動温度補償、素子の放射線耐性強化と大型化、Al蒸着を用いた太陽遮光など、宇宙利用のため世界に先がけて開発した。本衛星は、2007年の夏期にインドのPSLVを用いて打ち上げる予定である。次に、XI-Vの開発を進め、2005年10月にロシアのCOSMOSで打上げに成功し、現在まで1年5ヶ月にわたり運用を実施し、高度化した画像取得機能の確認、JAXAが開発したCIGSという新型太陽電池の軌道上実証を行い、放射線劣化のない良い世界初のデータが得られた。さらに高分解能の地球観測を行う5kg衛星PRISMの開発を行い、バス系の高度化と同時に、伸展マスト、オートフォーカス機構等のミッション系の研究も進めた。打ち上げに関してはJAXAのH-IIA公募に応募し、2008年夏期の打ち上げに向けて、BBMからEMフェーズに移って、設計の詳細化、機器の機能実証、宇宙環境試験を実施した。超小型衛星の適切なアーキテクチャと開発の方法論、打ち上げに向けての国際調整の方法、運用法など多くの成果が得られた
高い量子効率をもつ光電子増倍管の開発と、気球による硬X線偏光観測への応用

日本学術振興会科学研究費助成事業

研究期間:

2004年

-

2006年

片岡淳, 河合誠之, 郡司修一, 斉藤芳隆

　概要を見る

平成16年度から3ヵ年にわたる開発は滞りなく終了し、当初予定していた目標を大幅に上回る成果を挙げることができた。本開発期間で達成した項目は、以下の通りである。(1)光電子増倍管アセンブリ(高圧電源内蔵・気球搭載PMT-ASSY)の大量生産(2)7ユニット・プロトタイプ偏光計の試作と、放射光施設における性能評価(3)PoGOLite専用検出器シミュレータの開発(4)サイクロトロン陽子ビームによる荷電粒子応答試験(5)光電子増倍管1ユニットを搭載した気球動作実証本開発では、低ノイズかつ高性能な光電子増倍管に小型高圧電源を内蔵することで、気球環境で最適なアセンブリ約150ユニットを開発した。ガラス管に反射材を二重に巻きつける手法を新たに考案し、実質的な量子効率を6割も向上することに成功した(申請時の達成目標は3割)。これらをスタンフォード大学で製作したセンサー部と組み合わせ、7ユニットからなるプロトタイプ検出器を製作した。2005年-2007年にかけて高エネルギー研究所の放射光施設(KEK-PF)で3回の評価試験を行い、偏光検出器として十分な性能が達成されることを実証した(Kataoka et al.05,Kanai et al.07)。ここで得られたデータは詳細な検出器シミュレータを構築する上で不可欠であり、フライトモデルの製作と最適化の基盤にもなっている。製作した1ユニットに関しては大阪大学核物理研究センターのサイクロトロン施設において,392MeV/pの陽子ビームを照射し、観測時の荷電粒子(宇宙線)バックグラウンドの評価を行った。これらの詳細な試験の後、PMT-ASSY 1ユニットを気球に搭載し、郡司の指揮するPHENEX実験のモニターカウンタとして実際に使用した。16時間の気球フライト中、PMT-ASSYは一度も不具合を起こすことなく観測値をモニターし、天体(カニ星雲)を視野に含む数時間はガンマ線イベントの増加を確認するなど、単なる動作試験の枠を超え、科学的にも重要な成果を得ることに成功した
X線時間変動の観測を通した超巨大ブラックホールの基本計量測定

日本学術振興会科学研究費助成事業

研究期間:

2002年

-

2004年

林田清, 井上一, 粟木久光, 根来均, 片岡淳, 伊予本直子

　概要を見る

本研究の目標は、活動銀河核のX線時間変動を通して超巨大ブラックホールの質量など、その基本計量を推定することにある。X線強度とスペクトルの変化を通してブラックホール降着系の物理を探ることももう一つの目標であった。1.本研究をはじめるきっかけとなったのが、我々が開発した、活動銀河核のX線時間変動から中心ブラックホールの質量を経験的に推定する手法である。当初は、近傍の明るいセイファート1型銀河を対象としていたが、この3年間の研究で様々な種類の活動銀河核に応用をひろげた。ブレーザーを除く活動銀河核でその時間変動のパターン(パワースペクトル)は相似形で、我々の仮定したスケーリング則はおよそ成り立っているようにみえる。他の独立なブラックホール質量推定法とも一桁程度の範囲で矛盾ない値を与える。例えば、最小光度のセイファート1型銀河として知られるNGC4395に関してブラックホール質量推定値は10^4-10^5太陽質量で、恒星質量ブラックホールと超巨大質量ブラックホールの間を埋める位置にこのような天体が存在することを示した。超巨大質量ブラックホールの成因を考える上で重要なケースである。2.ブラックホールの強度変動とスペクトル変動の詳細に関してセイファート銀河,そして複数のブレーザーを観測した。例えば、MCG-6-30-15に関しては、通常ブラックホール近傍からの蛍光X線として解釈される鉄輝線に関して、電離したガスによる吸収モデルでも説明できることを示した。ジェットソースとも呼ばれるブレーザーに関しては、多波長の時間変動を説明するためにジェットの運動と輻射機構のモデルをこれまでより高い精度で確立し、衝撃波の物理に新たな知見を与えた。3.一方、ブラックホール降着系で激しい時間変動が起こるのはなぜかという根本的な疑問に関しては本研究では決着つけることができず将来の課題となった
半導体増幅素子APD,MPPCを用いた放射線検出器の開発（JST、NEDO、浜松ホトニクスほか）

研究期間:

2003年

-

　
新開発の大口径空気チェレンコフ望遠鏡を用いた活動銀河核からのTeVγ線放射の研究

日本学術振興会科学研究費助成事業

研究期間:

2000年

　

　

片岡淳
活動銀河核ジェットの観測的研究

研究期間:

1995年

-

　
衛星搭載用宇宙X線・ガンマ線検出器の開発（JAXAほか）

研究期間:

1995年

-

　
ガンマ線バースト即時観測用ロボット望遠鏡システムの開発

　概要を見る

本研究の目的は、HETE-2およびSwift衛星からインターネットを通じて配信されるガンマ線バースト速報に対応して、自動的に即時にバーストの方向を撮像する望遠鏡システムを開発し、ガンマ線バーストに伴う可視光フラッシュの観測を行なうことである。本年度は、次の作業を行なった。1.別予算にて岡山県美星天文台屋上に設置した口径30cm望遠鏡の測光精度を調査した。Landolt測光標準星との比較によれば、本システムはフィルター無しにもかかわらず、Rバンドでは標準星のカタログ等級と0.1等以下の誤差でよい比例関係をもつことを確かめた。2.昨年度に製作して宮崎大学工学部の屋上に設置したロボット望遠鏡システム第二号機の調整、試験を行い、指向・追尾性能試験および撮像試験を行った。試験観測として、美星天文台に設置した一号機とともに、変光星、獅子座流星群、超新星2002apなどの観測を行った。3.ロボット望遠鏡システムを統括制御するソフトウェアを改良し、自動観測運用を開始した。雨あるいは雪による機械的、あるいは電気的な不具合が生じたので、修理・対策を施した。4.HETE-2およびBeppoSAX衛星が検出したガンマ線バースト4個(GRB010921, GRB011019, GRB011030, GRB020124)に対して追観測を行った。可視対応天体の検出には至っていない
次世代データ処理を目指した、全天X線モニター地上試験システムの開発

　概要を見る

全天X線モニター(MAXI)は、2008年度に国際宇宙ステーション(ISS)日本モジュールに搭載される予定のX線検出器であり、現在試作モデルとフライト検出器の製作が行われている。本年は、MAXIプロジェクトの存続を決める上で最も重要な年で、CDR (Critical Design Review)をはじめとして搭載システムの詳細な検討が行われた。特にデジタルプロセッサー部分については、Release-2と呼ばれる試作モデルの性能評価を行ったが、地上試験でも機上と全く同じアナログ処理部を再現する必要があり、本研究で開発した「地上試験システム」が用いられた。昨年度は、同じシステムを全く逆の用途、つまり、アナログ処理部の詳細試験を行うための"擬似デジタルプロセッサー"として用いたが、本年度の試験を通じて申請の目的をすべて達成したことになる。ハードウェアとしては、昨年度製作したVME処理ボードを用いて、家庭用パソコン(CPU1GHz、メモリ512Mbyte)に接続して試験を行った。FPGAのプログラミングも全て終了し、本システムは現在、理化学研究所(宇宙放射線研究室)およびJAXA(宇宙環境計測システム)に常備され、様々な試験に役立てている。昨年度の実績とあわせ、本年度の開発の概要、開発したシステムについては8月の国際学会(SPIE)で口頭発表を行った。結果はSPIE学術誌2003,vol5165,375-386にkataoka et al.として掲載されている。発表においては多くの質問や活発な議論が行われ、改めてこの分野に対する研究者め関心の高さを実感した
MPPC光増幅素子を用いた革新的分子イメージング技術の開拓

▼全件表示

Misc

薬物動態を可視化する放射化イメージング：宇宙の元素合成を医療に応用

越川七星, 片岡淳

月刊化学 78 ( 5 ) 33 - 37 2023年04月 [招待有り]

担当区分：最終著者
陽子線照射即発X線と即発ガンマ線同時測定

山本誠一, 山下智弘, 小橋佑介, 矢部卓也, 山口充孝, 河地有木, 鎌田圭, 吉川彰, 赤城卓, 片岡淳

応用物理学会春季学術講演会講演予稿集(CD-ROM) 70th 2023年

J-GLOBAL
広帯域X線・ガンマ線による薬剤可視化へ向けた新技術

越川七星, 増渕美穂, 片岡淳

応用物理学会・放射線分科会会誌 48 ( 1 ) 14 - 22 2023年01月 [招待有り]
放射化イメージングによる高感度薬剤可視化の実証

越川七星, 増渕美穂, 片岡淳, 床井健運, 中川創太, 今田彩香, 松永恵子, 加藤弘樹, 角永悠一郎, 豊嶋厚史, 高宮幸一, 上田真史

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 83rd 2022年

J-GLOBAL
Progress CT 7.CT開発の最先端Photon-Counting CT

有元誠, 川嶋広貴, 小林聡, 片岡淳

日獨医報 66 ( 1 ) 2022年 [招待有り]

J-GLOBAL
コンプトンカメラを用いたアクティブ動態イメージング

片岡淳, 小俣陽久, 増渕美穂, 越川七星

2021年12月 [招待有り]
Spectral Photon-counting CT System based on Si-PM coupled with Novel Ceramic Scintillators

Radiation Detection Systems - Medical Imaging, Industrial Testing and Security Applications (CRC press) 2021年04月 [招待有り]
広帯域X線ガンマ線による新規イメージング手法の開発と実証

増渕美穂, 小俣陽久, 越川七星, 片岡淳, 加藤弘樹, 豊嶋厚史, 寺本高啓, 松永恵子, 神谷貴史, 渡部直史, 下瀬川恵久, 畑澤順, 上ノ町水紀

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 82nd 2021年

J-GLOBAL
広帯域X線ガンマ線による革新的放射化イメージング手法の提案 2

小俣陽久, 増渕美穂, 越川七星, 岡崎優, 片岡淳, 松永恵子, 加藤弘樹

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 82nd 2021年

J-GLOBAL
広帯域X線ガンマ線による革新的放射化イメージング手法の提案 1

越川七星, 小俣陽久, 増渕美穂, 岡崎優, 片岡淳, 松永恵子, 加藤弘樹

応用物理学会秋季学術講演会講演予稿集(CD-ROM) 82nd 2021年

J-GLOBAL
CTA報告172:全体報告

窪秀利, 手嶋政廣, 手嶋政廣, 戸谷友則, 浅野勝晃, 阿部日向, 阿部正太郎, 粟井恭輔, 井岡邦仁, 石尾一馬, 石尾一馬, 石崎渉, 稲田知大, 井上進, 井上剛志, 井上芳幸, 猪目祐介, 今澤遼, 岩村由樹, WARREN Donald, 内山泰伸, 大石理子, OWEN Ellis R., 大岡秀行, 大谷恵生, 大平豊, 岡知彦, 岡崎奈緒, 奥村曉, 奥村曉, 小原光太郎, 折戸玲子, 加賀谷美佳, 片岡淳, 片桐秀明, 勝田哲, KHALIKOV Emil, 川島翔太郎, 川中宣太, 川村孔明, 木坂将大, CUI Xiaohong, 櫛田淳子, 黒田裕介, 郡司修一, 郡和範, 小林志鳳, KONG Albert K. H., 齋藤隆之, 榊直人, 櫻井駿介, 佐々木寅旭, 佐々木陽香, 佐藤優理, 佐野栄俊, 澤田真理, 柴田徹, DZHATDOEV Timur, 鈴木寛大, 須田祐介, 須田祐介, STRZYS Marcel, STRZYS Marcel, 砂田裕志, ZENIN Anatolii, 高田順平, 高橋満里, 高橋慶太郎, 高橋弘充, 高橋光成, 武石隆治, 田島宏康, 立原研悟, 立石大, 田中周太, 田中孝明, 田中真伸, TAM Thomas P.H., CHENG K.S., 千川道幸, 塚本友祐, 鶴剛, TIAN Wenwu, 寺内健太, 寺田幸功, 當真賢二, 門叶冬樹, 内藤統也, 長瀧重博, 中森健之, 中山和則, 生天目康之, 西嶋恭司, 野上優人, 野崎誠也, 野田浩司, 野村亮介, BARKOV Maxim, 芳賀純也, バクスタージョシュア稜, 橋山和明, HADASCH Daniela, 早川貴敬, 林克洋, 林航平, 林田将明, 原敏, 原田善規, 馬場彩, 平松明秀, 廣島渚, 広谷幸一, HUI David C.Y., FERRAND Gilles, 深沢泰司, 深見哲志, 福井康雄, 藤川由衣, 藤田裕, HE Haoning

日本物理学会講演概要集(CD-ROM) 76 ( 1 ) 556 - 556 2021年

DOI J-GLOBAL
Activity bubbling up

Jun Kataoka

Nature Astronomy 5 ( 1 ) 11 - 12 2021年01月

速報，短報，研究ノート等（学術雑誌）

DOI
4種類の機械学習技術を用いたコンプトンカメラ画像解析

佐藤将吾, 片岡淳, 古徳純一, 瀧雅人, 大山飛鳥, 田川怜央, 藤枝和也, 西郁也, 豊田貴也

応用物理学会春季学術講演会講演予稿集(CD-ROM) 67th 2020年

J-GLOBAL
次世代光センサーMPPCと高速シンチレータの融合による革新的X線CTへの挑戦

有元誠, 片岡淳, 寺澤慎祐, 塩田諭

日立金属技報 36 28 - 33 2020年01月 [招待有り]

機関テクニカルレポート，技術報告書，プレプリント等
The CALorimetric Electron Telescope (CALET) on the international space station: Results from the first two years on orbit

Y. Asaoka, O. Adriani, Y. Akaike, K. Asano, M. G. Bagliesi, E. Berti, G. Bigongiari, W. R. Binns, S. Bonechi, M. Bongi, A. Bruno, P. Brogi, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, V. Di Felice, K. Ebisawa, H. Fuke, T. G. Guzik, T. Hams, N. Hasebe, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, T. Lomtadze, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, K. Mori, M. Mori, N. Mori, H. M. Motz, K. Munakata, H. Murakami, S. Nakahira, J. Nishimura, G. A. De Nolfo, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, F. Palma, V. Pal'Shin, P. Papini, A. V. Penacchioni, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, R. Sparvoli, P. Spillantini, F. Stolzi, S. Sugita, J. E. Suh, A. Sulaj, I. Takahashi, M. Takayanagi, M. Takita, T. Tamura, N. Tateyama, T. Terasawa, H. Tomida, S. Torii, Y. Tsunesada, Y. Uchihori, S. Ueno, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida

Journal of Physics: Conference Series 1181 ( 1 ) 2019年03月 [査読有り]

　概要を見る

© Published under licence by IOP Publishing Ltd. The CALorimetric Electron Telescope (CALET) is a high-energy astroparticle physics space experiment installed on the International Space Station (ISS), developed and operated by Japan in collaboration with Italy and the United States. The CALET mission goals include the investigation of possible nearby sources of high-energy electrons, of the details of galactic particle acceleration and propagation, and of potential signatures of dark matter. CALET measures the cosmic-ray electron+positron flux up to 20 TeV, gamma-rays up to 10 TeV, and nuclei with Z=1 to 40 up to 1, 000 TeV for the more abundant elements during a long-term observation aboard the ISS. Starting science operation in mid-October 2015, CALET performed continuous observation without major interruption with close to 20 million triggered events over 10 GeV per month. Based on the data taken during the first two-years, we present an overview of CALET observations: 1) Electron+positron energy spectrum, 2) Nuclei analysis, 3) Gamma-ray observation including a characterization of on-orbit performance. Results of the electromagnetic counterpart search for LIGO/Virgo gravitational wave events are discussed as well.

DOI
CTA 報告 155：全体報告

手嶋政廣, 窪秀利, 戸谷友則, 浅野勝晃, 井岡邦仁, 石尾一馬, 稲田知大, 井上進, 井上剛志, 井上芳幸, 猪目祐介, 岩村由樹, 内山泰伸, 大石理子, 大岡秀行, 大谷恵生, 大平豊, 岡知彦, 岡崎奈緒, 緒方智之, 奥村曉, 折戸玲子, 加賀谷美佳, 梶原侑貴, 片岡淳, 片桐秀明, 勝倉大輔, 勝田哲, 川中宣太, 木坂将大, 櫛田淳子, 郡司修一, 郡和範, 小林志鳳, 齋藤隆之, 榊直人, 櫻井駿介, 佐野栄俊, 澤田真理, 柴田徹, 鈴木萌, 鈴木寛大, 須田祐介, 砂田裕志, 高田順平, 高橋慶太郎, 高橋弘充, 高橋光成, 田島宏康, 立原研悟, 田中周太, 田中孝明, 田中真伸, 田村謙治, 千川道幸, 町支勇貴, 辻本晋平, 鶴剛, 寺田幸功, 當真賢二, 門叶冬樹, 内藤統也, 長瀧重博, 中村裕樹, 中森健之, 中山和則, 西嶋恭司, 野崎誠也, 野田浩司, 早川貴敬, 林克洋, 林田将明, 原敏, 馬場彩, 日高直哉, 廣島渚, 広谷幸一, 深沢泰司, 深見哲志, 福井康雄, 藤田裕, 藤原千賀己, 古田智也, 松本浩典, 水野恒史, 村石浩, 村瀬孔大, 森浩二, 柳田昭平, 山崎了, 山根悠望子, 山本常夏, 山本宏昭, 吉越貴紀, 吉田篤正, 吉田龍生, 李兆衡

日本物理学会講演概要集 74.2 358 - 358 2019年

DOI CiNii
HITOMI (ASTRO-H) X-ray astronomy satellite

Tadayuki Takahashi, Motohide Kokubun, Kazuhisa Mitsuda, Richard L. Kelley, Takaya Ohashi, Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Naohisa Anabuki, Lorella Angelini, Keith Arnaud, Makoto Asai, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Philipp Azzarello, Chris Baluta, Aya Bamba, Nobutaka Bando, Marshall W. Bautz, Thomas Bialas, Roger Blandford, Kevin Boyce, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Edgar Canavan, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Steve O' Dell, Michael DiPirro, Chris Done, Tadayasu Dotani, John Doty, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Stefan Funk, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Kirk Gilmore, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Daniel Haas, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Takayuki Hayashi, Katsuhiro Hayashi, Kiyoshi Hayashida, Jan Willem Den Herder, Junko S. Hiraga, Kazuyuki Hirose, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Kazunori Ishibashi, Manabu Ishida, Kumi Ishikawa, Kosei Ishimura, Yoshitaka Ishisaki, Masayuki Itoh, Masachika Iwai, Naoko Iwata, Naoko Iyomoto, Chris Jewell, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Erin Kara, Jun Kataoka, Satoru Katsuda, Junichiro Katsuta, Madoka Kawaharada, Nobuyuki Kawai, Taro Kawano, Shigeo Kawasaki, Dmitry Khangulyan, Caroline A. Kilbourne, Mark Kimball

Journal of Astronomical Telescopes, Instruments, and Systems 4 ( 2 ) 2018年04月

書評論文，書評，文献紹介等

　概要を見る

The Hitomi (ASTRO-H) mission is the sixth Japanese x-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E > 2 keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decades in energy from soft x-rays to gamma rays. After a successful launch on February 17, 2016, the spacecraft lost its function on March 26, 2016, but the commissioning phase for about a month provided valuable information on the onboard instruments and the spacecraft system, including astrophysical results obtained from first light observations. The paper describes the Hitomi (ASTRO-H) mission, its capabilities, the initial operation, and the instruments/spacecraft performances confirmed during the commissioning operations for about a month.

DOI
「ひとみ」HXIを用いた軌道上中性子バックグラウンドの評価

鈴木寛大, 中澤知洋, 萩野浩一, 国分紀秀, 佐藤悟朗, 高橋忠幸, 渡辺伸, 太田方之, 佐藤理江, 森國城, 村上浩章, 三宅克馬, 古田禄大, 馬場彩, 鶴剛, 田中孝明, 榎戸輝揚, 小林翔悟, 寺田幸功, 内山秀樹, 谷津洋一, 野田博文, 田島宏康, 山岡和貴, 林克洋, 林克洋, 深沢泰司, 水野恒史, 大野雅功, 高橋弘充, 勝田隼一郎, 中森健之, 内山泰伸, 斉藤新也, 牧島一夫, 小高裕和, 湯浅孝行, 中野俊男, 片岡淳, 三村健人, LEBRUN Francois, LIMOUSIN Olivier, LAURENT Philippe, MAIER Daniel, 武田伸一郎, 森浩二

日本天文学会年会講演予稿集 2018 227 2018年02月

J-GLOBAL
増幅型光センサーMPPCを用いた低被ばく・多色CTへの挑戦

有元誠, 片岡淳

Isotope News (Web) ( 755 ) 25‐29 (WEB ONLY) 2018年02月 [招待有り]

記事・総説・解説・論説等（学術雑誌）

　概要を見る

http://jglobal.jst.go.jp/public/201802266984173612

J-GLOBAL
CTA報告139：全体報告

窪秀利, 井上剛志, 深見哲志, 福井康雄, 藤田裕, 藤原千賀己, He Haoning, Majumdar Pratik, Mazin Daniel, 増田周, 松本浩典, 三浦智佳, 井上芳幸, 水野恒史, 村石浩, 村瀬孔大, 森浩二, 柳田昭平, 山崎了, 山本常夏, 山本宏昭, 吉池智史, 吉越貴紀, 猪目祐介, 吉田篤正, 吉田龍生, 李健, 李兆衡, 岩村由樹, Warren Donald, 内山泰伸, 大石理子, 大岡秀行, 大平豊, 岡崎奈緒, 手嶋政廣, 奥村曉, 折戸玲子, 加賀谷美佳, 格和純, 片岡淳, 片桐秀明, 勝倉大輔, 勝田哲, 加藤翔, 神本匠, 戸谷友則, 川中宣太, 木坂将大, 木村颯一朗, Cui Xiaohong, 櫛田淳子, 久門拓, 黒田隼人, 郡司修一, 郡和範, 小山志勇, 朝野彰, Kong Albert K. H, 齋藤隆之, 榊直人, 櫻井駿介, 佐々井義矩, 佐野栄俊, 澤田真理, 柴田徹, Dzhatdoev Timur, 鈴木萌, 浅野勝晃, 砂田裕志, 関崎晴仁, Zenin Anatolii, 高田順平, 高橋慶太郎, 高橋知也, 高橋弘充, 高橋光成, 髙原大, 田島宏康, 井岡邦仁, 立原研悟, 田中周太, 田中孝明, 田中真伸, 田中康之, 種田裕貴, Tam Thomas P. H, Cheng K. S, 千川道幸, 辻本晋平, 石尾一馬, 鶴剛, Tian Wenwu, 寺田幸功, 當真賢二, 門叶冬樹, 内藤統也, 中嶋大輔, 長瀧重博, 中村裕樹, 中森健之, 稲田知大, 中山和則, 永吉勤, 西嶋恭司, 西山楽, 野崎誠也, 野田浩司, Barkov Maxim, Hadasch Daniela, 早川貴敬, 林克洋, 井上進, 林田将明, 原敏, 馬場彩, 日高直哉, 平子丈, 廣島渚, 広谷幸一, Hui David, C. Y, Ferrand Gilles, 深沢泰司

日本物理学会講演概要集 73 ( 0 ) 188 - 188 2018年

DOI CiNii J-GLOBAL
CTA報告130：全体報告

手嶋政廣, 井上剛志, 藤田裕, He Haoning, Majumdar Pratik, Mazin Daniel, 増田周, 松本浩典, 三浦智佳, 水野恒史, 村石浩, 村瀬孔大, 井上芳幸, 森浩二, 柳田昭平, 山崎了, 山本常夏, 山本宏昭, 吉池智史, 吉越貴紀, 吉田篤正, 吉田龍生, 李健, 猪目祐介, 李兆衡, Consortium for, the CTA-Japan, 岩村由樹, Warren Donald, 内山泰伸, 大石理子, 大岡秀行, 大平豊, 岡崎奈緒, 窪秀利, 奥村曉, 折戸玲子, 加賀谷美佳, 格和純, 片岡淳, 片桐秀明, 勝倉大輔, 勝田哲, 加藤翔, 神本匠, 戸谷友則, 川中宣太, 木坂将大, 木村颯一朗, Cui Xiaohong, 櫛田淳子, 久門拓, 黒田隼人, 郡司修一, 郡和範, 小山志勇, 浅野勝晃, Kong Albert K. H, 齋藤隆之, 榊直人, 櫻井駿介, 佐々井義矩, 佐野栄俊, 澤田真理, 柴田徹, Dzhatdoev Timur, 砂田裕志, 朝野彰, 関崎晴仁, 高田順平, 高橋慶太郎, 高橋知也, 高橋弘充, 高橋光成, 高原大, 田島宏康, 立原研悟, 田中周太, 井岡邦仁, 田中孝明, 田中真伸, 田中康之, 種田裕貴, Tam Thomas P. H, Cheng K. S, 千川道幸, 辻本晋平, 鶴剛, Tian Wenwu, 石尾一馬, 寺田幸功, 當真賢二, 門叶冬樹, 内藤統也, 中嶋大輔, 長瀧重博, 中村裕樹, 中森健之, 中山和則, 永吉勤, 稲田知大, 西嶋恭司, 西山楽, 野崎誠也, 野田浩司, Barkov Maxim, Hadasch Daniela, 早川貴敬, 林克洋, 林田将明, 原敏, 井上進, 馬場彩, 日高直哉, 平子丈, 廣島渚, 広谷幸一, Hui David, C. Y, Ferrand Gilles, 深沢泰司, 深見哲志, 福井康雄

日本物理学会講演概要集 73 ( 0 ) 412-412 - 412 2018年

DOI CiNii
高精度陽子線治療を目指した画期的陽子線CTシステムの開発

有元誠, 高部美穂, 増田孝充, 片岡淳, 羽鳥聡, 久米恭, 長谷川崇

若狭湾エネルギー研究センター研究年報 19 45‐47 2017年10月

機関テクニカルレポート，技術報告書，プレプリント等

J-GLOBAL
森林除染に向けたドローン活用事例:里山における空間線量率の鉛直観測とドローン搭載ガンマ線カメラによる迅速調査への活用

大河内博, 片岡淳, 岸本彩, 岩本康弘, 金野俊太郎, 黒島碩人, 勝見尚也, 緒方裕子, 反町篤行, 床次眞司

大気環境学会年会講演要旨集 58th 140‐142 2017年08月

J-GLOBAL
CTA報告117：全体報告

手嶋政廣, 窪秀利, 戸谷友則, 朝野彰, 浅野勝晃, 井岡邦仁, 池野祐平, 石尾一馬, 稲田知大, 井上進, 井上剛志, 井上芳幸, 猪目祐介, 岩村由樹, 内山泰伸, 梅津陽平, 大石理子, 大岡秀行, 大平豊, 岡崎奈緒, 奥村曉, 折戸玲子, 加賀谷美佳, 格和純, 片岡淳, 片桐秀明, 加藤翔, 川中宣太, 木坂将大, 岸田柊, 木村颯一朗, 櫛田淳子, 黒田隼人, 郡司修一, 郡和範, 小山志勇, 今野裕介, 齋藤隆之, 榊直人, 櫻井駿介, 佐藤雄太, 佐野栄俊, 澤田真理, 重中茜, 柴田徹, 高田順平, 高橋慶太郎, 高橋弘充, 高橋光成, 高見将太, 武田淳希, 田島宏康, 立原研悟, 田中周太, 田中孝明, 田中真伸, 田中康之, 谷川俊介, 千川道幸, 辻本晋平, 鶴剛, 寺田幸功, 當真賢二, 門叶冬樹, 友野弥生, 内藤統也, 中嶋大輔, 長瀧重博, 中村裕樹, 中森健之, 中山和則, 永吉勤, 西嶋恭司, 西山楽, 野崎誠也, 野田浩司, 早川貴敬, 林克洋, 林田将明, 原敏, 馬場彩, 日高直哉, 平井亘, 廣島渚, 広谷幸一, 深沢泰司, 深見哲志, 福井康雄, 藤田裕, 増田周, 松本浩典, 水野恒史, 村石浩, 村瀬孔大, 本橋大輔, 森浩二, 柳田昭平, 山崎了, 山根暢仁, 山本常夏, 山本宏昭, 吉池智史, 吉越貴紀, 吉田篤正, 吉田龍生, 吉田麻佑, 李兆衡

日本物理学会講演概要集 72.1 457 - 457 2017年

　概要を見る

CTA (Cherenkov Telescope Array) は次世代の国際宇宙ガンマ線天文台であり、従来に無い感度と精度で、20GeVから200TeVのエネルギー領域で、全天からの高エネルギーガンマ線を観測する。1000を超える多種多様な天体を銀河系内、銀河系外に観測し、高エネルギー宇宙物理を飛躍的に発展させる。銀河系内の全ての超新星残骸をサーベイし、銀河宇宙線の起源を明らかにする。また、銀河系外の観測では、活動銀河核・ガンマ線バーストをz<4まで観測し、超高エネルギーガンマ線の地平線を大きく拡げる。また、銀河中心領域、また矮小楕円銀河に暗黒物質対消滅からのガンマ線を探索する。CTAのサイエンスは、宇宙物理から基礎物理まで大きな拡がりをもつ。CTAの南北のサイトが、チリ・パラナル、スペイン・ラパルマに決定され、2016年よりラパルマにて大口径望遠鏡４基の建設が開始されている。本講演では、国内外でのCTA計画の準備状況について報告する。

DOI CiNii
粒子線治療オンラインモニタに向けたコンプトンカメラ画像再構成の最適化と実機検証

多屋隆紀, 片岡淳, 岸本彩, 田川怜央, 望月早駆, 歳藤利行, 木村充宏, 河地有木, 山口充孝, 長尾悠人, 栗田圭輔

応用物理学会春季学術講演会講演予稿集(CD-ROM) 64th 2017年

J-GLOBAL
医療用コンプトンカメラによる3次元小動物イメージング

岸本彩, 片岡淳, 田川怜央, 望月早駆, 多屋隆紀, 大須賀慎二, 松永恵子, 池田隼人, 下瀬川恵久, 畑澤順, 河地有木, 長尾悠人, 山口充孝, 栗田圭輔

応用物理学会春季学術講演会講演予稿集(CD-ROM) 64th 2017年

J-GLOBAL
「ひとみ」搭載硬X線・軟ガンマ線帯観測装置の軌道上性能

粟木久光, 松本浩典, 石田学, 中澤知洋, 国分紀秀, 田島宏康, 深沢泰司, 渡辺伸, 幅良統, 飯塚亮, 太田方之, 佐藤理江, 高橋忠幸, 萩野浩一, 原山淳, 前田良知, 吉田鉄生, 武田伸一郎, 宮澤拓也, 榎戸輝揚, 田中孝明, 寺田幸功, 内山秀樹, 一戸悠人, 石橋和紀, 國枝秀世, 田村啓輔, 田原譲, 三石郁之, 林克洋, 林多佳由, 山岡和貴, 大野雅功, 北口貴雄, 高橋弘充, 田中康之, 水野恒史, 杉田聡司, 谷津陽一, 野田博文, 古澤彰浩, 山内茂雄, 中森健之, 中野俊男, 牧島一夫, 内山泰伸, 斉藤新也, 片岡淳, Philippe Laurent, Francois Lebrun, Olivier Limousin, 岡島崇, 森英之, 小高裕和, Madejski G., Blanford R., 他「ひとみ」チーム

第17回宇宙科学シンポジウム講演集 = Proceedings of the 17th Space Science Symposium 2017年01月

　概要を見る

第17回宇宙科学シンポジウム (2017年1月5日-6日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)相模原キャンパス), 相模原市, 神奈川県著者人数: 56名ほか (JAXA staff: Ishida, Manabu ; Kokubun, Motohide ; Watanabe, Shin ; Iizuka, Ryo ; Ohta, Masayuki ; Sato, Rie ; Takahashi, Tadayuki ; Hagino, Koichi ; Harayama, Atsushi ; Maeda, Yoshitomo)資料番号: SA6000060046レポート番号: P-004

CiNii
福島県の里山に大気沈着した放射性セシウムの長期変動

金野俊太郎, 大河内博, 黒島碩人, 勝見尚也, 緒方裕子, 片岡淳, 岸本彩, 岩本康弘, 反町篤行, 床次眞司

日本地球惑星科学連合大会予稿集(Web) 2017 ROMBUNNO.MAG34‐P03 (WEB ONLY) 2017年

J-GLOBAL
ひとみ(ASTRO‐H)衛星搭載硬X線軟ガンマ線検出器BGOアクティブシールドの軌道上性能

大野雅功, 深沢泰司, 水野恒史, 高橋弘充, 北口貴雄, 田中康之, 勝田隼一郎, 河野貴文, 白川裕章, 枝廣育実, 幅田翔, 岡田千穂, 大橋礼恵, 田中晃司, 高橋忠幸, 国分紀秀, 渡辺伸, 佐藤悟朗, 太田方之, 萩野浩一, 佐藤理江, 森國城, 内田悠介, 桂川美穂, 都丸亮太, 米田浩基, 中澤知洋, 鳥井俊輔, 桜井壮希, 笹野理, 西田瑛量, 小林翔悟, 村上浩章, 小野光, 加藤佑一, 三宅克馬, 古田禄大, 室田優紀, 田島宏康, 木下将臣, 山岡和貴, 林克洋, 林克洋, 片岡淳, 斎藤龍彦, 吉野将生, 三村健人, 谷津陽一, 斉藤新也, 内山秀樹, 中森健之, 武田伸一郎, 中野俊男, 一戸悠人

日本物理学会講演概要集(CD-ROM) 71 ( 2 ) ROMBUNNO.24aSP‐8 - 372 2016年09月

　概要を見る

2016年2月に打ち上げられた「ひとみ(ASTRO-H)」衛星搭載の硬X線及び軟ガンマ線検出器における徹底したバックグラウンド除去を担うBGOアクティブシールドについて、およそ2週間の衛星軌道上運用において計72ユニット全てのシールド系を問題なく動作させることに成功した。バックグラウンド除去機能や突発天体観測機能などの全ての機能も想定通り動作しており、本講演で衛星軌道上において実証された性能について報告する。

DOI CiNii J-GLOBAL
里山に大気沈着した放射性Csの動態と環境調和型除染技術の開発(2)

金野俊太郎, 大河内博, 緒方裕子, 勝見尚也, 反町篤行, 床次眞司, 片岡淳, 岸本彩

大気環境学会年会講演要旨集 57th 250 2016年08月

J-GLOBAL
X線天文衛星「ひとみ(ASTRO‐H)」搭載硬X線撮像検出器(HXI)の軌道上動作

萩野浩一, 中澤知洋, 国分紀秀, 佐藤悟朗, 高橋忠幸, 渡辺伸, 太田方之, 佐藤理江, LEE Herman, 能町正治, 米徳大輔, 田中孝明, 榎戸輝揚, 寺田幸功, 内山秀樹, 谷津洋一, 一戸悠人, 野田博文, 田島宏康, 山岡和貴, 林克洋, 林克洋, 深沢泰司, 水野恒史, 大野雅功, 高橋弘充, 中森健之, 内山泰伸, 斉藤新也, 牧島一夫, 湯浅孝行, 中野俊男, 片岡淳, LEBRUN Francois, GOLDWURM Andrea, LIMOUSIN Olivier, LAURENT Philippe, MAIER Daniel, 武田伸一郎, 小高裕和

日本天文学会年会講演予稿集 2016 245 2016年08月

J-GLOBAL
「ひとみ(ASTRO‐H)」搭載SGDのBGOシールドを用いたガンマ線バースト位置決定能力の評価

田中晃司, 大野雅功, 深沢泰司, 水野恒史, 高橋弘充, 北口貴雄, 田中康之, 勝田隼一郎, 河野貴文, 白川裕章, 枝廣育実, 幅田翔, 岡田千穂, 大橋礼恵, 高橋忠幸, 国分紀秀, 渡辺伸, 佐藤悟朗, 太田方之, 萩野浩一, 佐藤理江, 森國城, 内田悠介, 桂川美穂, 都丸亮太, 米田浩基, 中澤知洋, 鳥井俊輔, 桜井壮希, 笹野理, 西田瑛量, 小林翔悟, 村上浩章, 小野光, 加藤佑一, 三宅寛馬, 古田禄大, 室田優紀, 田島宏康, 木下将臣, 山岡和貴, 林克洋, 林克洋, 片岡淳, 斎藤龍彦, 吉野将生, 三村健人, 谷津陽一, 斉藤新也, 内山秀樹, 中森健之, 武田伸一郎, 中野俊男, 一戸悠人

日本天文学会年会講演予稿集 2016 246 2016年08月

J-GLOBAL
「ひとみ(ASTRO‐H)」搭載硬X線軟ガンマ線検出器におけるBGOアクティブシールドの軌道上性能

大野雅功, 深沢泰司, 水野恒史, 高橋弘充, 北口貴雄, 田中康之, 勝田隼一郎, 河野貴文, 白川裕章, 枝廣育実, 幅田翔, 岡田千穂, 大橋礼恵, 田中晃司, 高橋忠幸, 国分紀秀, 渡辺伸, 佐藤悟朗, 太田方之, 萩野浩一, 佐藤理江, 森國城, 内田悠介, 桂川美穂, 都丸亮太, 米田浩基, 中澤知洋, 鳥井俊輔, 桜井壮希, 笹野理, 西田瑛量, 小林翔悟, 村上浩章, 小野光, 加藤佑一, 三宅克馬, 古田禄大, 室田優紀, 田島宏康, 木下将臣, 山岡和貴, 林克洋, 林克洋, 片岡淳, 斎藤龍彦, 吉野将生, 三村健人, 谷津陽一, 斉藤新也, 内山秀樹, 中森健之, 武田伸一郎, 中野俊男, 一戸悠人

日本天文学会年会講演予稿集 2016 245 2016年08月

J-GLOBAL
ASTRO‐H衛星搭載硬X線撮像検出器(HXI)の現状打ち上げ

中澤知洋, 国分紀秀, 佐藤悟朗, 萩野浩一, 太田方之, 小高裕和, 川原田円, 佐藤理江, 高橋忠幸, 武田伸一郎, 原山淳, 渡辺伸, 榎戸輝揚, 田中孝明, 寺田幸功, 内山秀樹, 谷津陽一, 中野俊男, 田島宏康, 山岡和貴, 大野雅功, 勝田隼一郎, 高橋弘充, 深沢泰司, 水野恒史, 中森健之, 野田博文, 牧島一夫, 湯浅孝行, 内山泰伸, 斉藤新也, 片岡淳, LAURENT Philippe, LEBRUN Francois, LIMOUSIN Okivier

日本天文学会年会講演予稿集 2016 211 2016年02月

J-GLOBAL
ASTRO‐H搭載硬X線撮像検出器(HXI)の地上試験における最終性能

小林翔悟, 佐藤悟朗, 萩野浩一, 中野俊男, 中澤知洋, 湯浅孝行, 牧島一夫, 榎戸輝揚, 佐藤理江, 渡辺伸, 国分紀秀, 高橋忠幸, 斉藤新也, 内山泰伸, 片岡淳, 谷津陽一, 北口貴雄, 大野雅功, 高橋弘充, 水野恒史, 深沢泰司, 田島宏康, 寺田幸功, 中森健之, LIMOUSIN Olivier, LAURENT Philippe, LEBRUN Francois

日本物理学会講演概要集(CD-ROM) 70 ( 2 ) ROMBUNNO.25PSJ-4 - 352 2015年09月

DOI CiNii J-GLOBAL
ASTRO‐H衛星搭載硬X線撮像検出器(HXI)の現状打上げに向けて

中澤知洋, 国分紀秀, 佐藤悟朗, 萩野浩一, 太田方之, 小高裕和, 川原田円, 佐藤理江, 高橋忠幸, 武田伸一郎, 原山淳, 渡辺伸, 榎戸輝揚, 田中孝明, 寺田幸功, 内山秀樹, 谷津陽一, 中野俊男, 牧島一夫, 田島宏康, 山岡和貴, 大野雅功, 勝田隼一郎, 高橋弘充, 深沢泰司, 水野恒史, 中森健之, 野田博文, 湯浅孝行, 内山泰伸, 斉藤新也, 片岡淳, LAURENT Philippe, LEBRUN Francois, LIMOUSIN Olivier

日本天文学会年会講演予稿集 2015 255 2015年08月

J-GLOBAL
福島県の里山に大気沈着した放射性セシウムの動態解明と環境調和型除染技術の開発(1)

金野俊太郎, 大河内博, 黒島碩人, 緒方裕子, 反町篤行, 床次眞司, 細田正洋, 片岡淳, 岸本彩

環境化学討論会要旨集(CD-ROM) 24th ROMBUNNO.P‐174 2015年06月

J-GLOBAL
Recent progress of MPPC-based scintillation detectors in high precision X-ray and gamma-ray imaging

J. Kataoka, A. Kishimoto, T. Fujita, T. Nishiyama, Y. Kurei, T. Tsujikawa, T. Oshima, T. Taya, Y. Iwamoto, H. Ogata, H. Okochi, S. Ohsuka, H. Ikeda, S. Yamamoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 784 248 - 254 2015年06月

　概要を見る

The multi-pixel photon counter (MPPC) is a promising light sensor for various applications, not only in physics experiments but also in nuclear medicine, industry, and even high-energy astrophysics. In this paper, we present the current status and most recent progress of the MPPC-based scintillation detectors, such as (1) a high-precision X-ray and gamma-ray spectral image sensor, (2) next-generation PET detectors with MRI, TOF, and DOI measurement capabilities, and (3) a compact gamma camera for environmental radiation surveys. We first present a new method of fabricating a Ce:GAGG scintillator plate (1 or 2 mm thick) with ultra-fine resolution (0.2 mm/pixel), cut using a dicing saw to create 50 mu m wide micro-grooves. When the plate is optically coupled with a large-area MPPC array, excellent spatial resolution of 0.48 mm (FWHM) and energy resolution of 14% (FWHM) are obtained for 122 keV gamma rays. Hence, the detector can act as a convenient "multi-color" imaging device that can potentially be used for future SPECT and photon-counting CT. We then show a prototype system for a high-resolution MPPC-based PET scanner that can realize similar or equal to 1 mm (FWHM) spatial resolution, even under a strong magnetic field of 4.7 T. We develop a front-end ASIC intended for future TOF-PET scanner with a 16-channel readout that achieves a coincidence time resolution of 489 ps (FWHM). A novel design for a module with DOI-measurement capability for gamma rays is also presented by measuring the pulse height ratio of double-sided MPPCs coupled at both ends of scintillation crystal block. Finally, we present the concept of a two-plane Compton camera consisting of Ce:GAGG scintillator arrays coupled with thin MPPC arrays. As a result of the thin and compact features of the MPPC device, the camera not only achieves a small size (14 x 14 x 15 cm(3)) and light weight (1.9 kg) but also excellent sensitivity, compared to the conventional PMT-based pinhole camera used in Fukushima. Finally, we briefly describe a new product recently developed in conjunction with Hamamatsu Photonics K.K. that offers improved sensitivity and angular resolution of Delta theta similar to 8 degrees (FWHM) at 662 key, by incorporating DOI-segmented scintillator arrays. (C) 2014 Elsevier B.V. All rights reserved.

DOI
Recent progress of MPPC-based scintillation detectors in high precision X-ray and gamma-ray imaging

J. Kataoka, A. Kishimoto, T. Fujita, T. Nishiyama, Y. Kurei, T. Tsujikawa, T. Oshima, T. Taya, Y. Iwamoto, H. Ogata, H. Okochi, S. Ohsuka, H. Ikeda, S. Yamamoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 784 248 - 254 2015年06月

　概要を見る

The multi-pixel photon counter (MPPC) is a promising light sensor for various applications, not only in physics experiments but also in nuclear medicine, industry, and even high-energy astrophysics. In this paper, we present the current status and most recent progress of the MPPC-based scintillation detectors, such as (1) a high-precision X-ray and gamma-ray spectral image sensor, (2) next-generation PET detectors with MRI, TOF, and DOI measurement capabilities, and (3) a compact gamma camera for environmental radiation surveys. We first present a new method of fabricating a Ce:GAGG scintillator plate (1 or 2 mm thick) with ultra-fine resolution (0.2 mm/pixel), cut using a dicing saw to create 50 mu m wide micro-grooves. When the plate is optically coupled with a large-area MPPC array, excellent spatial resolution of 0.48 mm (FWHM) and energy resolution of 14% (FWHM) are obtained for 122 keV gamma rays. Hence, the detector can act as a convenient "multi-color" imaging device that can potentially be used for future SPECT and photon-counting CT. We then show a prototype system for a high-resolution MPPC-based PET scanner that can realize similar or equal to 1 mm (FWHM) spatial resolution, even under a strong magnetic field of 4.7 T. We develop a front-end ASIC intended for future TOF-PET scanner with a 16-channel readout that achieves a coincidence time resolution of 489 ps (FWHM). A novel design for a module with DOI-measurement capability for gamma rays is also presented by measuring the pulse height ratio of double-sided MPPCs coupled at both ends of scintillation crystal block. Finally, we present the concept of a two-plane Compton camera consisting of Ce:GAGG scintillator arrays coupled with thin MPPC arrays. As a result of the thin and compact features of the MPPC device, the camera not only achieves a small size (14 x 14 x 15 cm(3)) and light weight (1.9 kg) but also excellent sensitivity, compared to the conventional PMT-based pinhole camera used in Fukushima. Finally, we briefly describe a new product recently developed in conjunction with Hamamatsu Photonics K.K. that offers improved sensitivity and angular resolution of Delta theta similar to 8 degrees (FWHM) at 662 key, by incorporating DOI-segmented scintillator arrays. (C) 2014 Elsevier B.V. All rights reserved.

DOI
ASTRO‐H衛星搭載硬X線軟ガンマ線検出器におけるBGOアクティブシールドの地上較正試験

大野雅功, 河野貴文, 古井俊也, 枝廣育実, 白川裕章, 勝田隼一郎, 田中康之, 高橋弘充, 水野恒史, 深沢泰司, 村上浩章, 小林翔悟, 三宅克馬, 小野光, 室田優紀, 中澤知洋, 牧島一夫, 佐藤悟朗, 片岡淳, 一戸悠人, 内田悠介, 桂川美穂, 武田伸一郎, 佐藤理江, 川原田円, 原山淳, 小高浩和, 林克洋, 太田方之, 渡辺伸, 国分紀秀, 高橋忠幸, 木下将臣, 山岡和貴, 田島宏康, 谷津陽一, 内山秀樹, 斉藤新也, 湯浅孝行

日本物理学会講演概要集(CD-ROM) 70 ( 1 ) ROMBUNNO.23PDK-5 2015年03月

J-GLOBAL
ASTRO‐H衛星搭載硬X線撮影検出器(HXI)の現状FMの完成

中澤知洋, 国分紀秀, 佐藤悟朗, 川原田円, 佐藤理江, 渡辺伸, 高橋忠幸, 太田方之, 小高裕和, 武田伸一郎, 原山淳, 斉藤新也, 湯浅孝行, 谷津陽一, 内山秀樹, 田島宏康, 山岡和貴, 深沢泰司, 水野恒史, 大野雅功, 高橋弘充, 勝田隼一郎, 寺田幸功, 牧島一夫, 片岡淳, 野田博文, 榎戸輝揚, 田中孝明, 内山泰伸, 中森健之, LIMOUSIN Olivier, LAURENT Philippe, LEBRUN Francois, 櫻井壮希, 笹野理, 中野俊男, 小林翔悟, 村上浩章, 小野光, 加藤佑一

日本天文学会年会講演予稿集 2015 262 2015年02月

J-GLOBAL
24aDJ-2 硬X線偏光観測衛星TSUBAMEの打上げ(II)

谷津陽一, 森山永久, 木村真一, 片岡淳, 中森健之, 久保信, 栗田真, 大内遥河, 有元誠, 河合誠之, 松下将典, 河尻翔太, 長洲孝, 松永三郎

日本物理学会講演概要集 70 ( 0 ) 2015年

CiNii
福島県浪江町の里山における放射性セシウムの分布と動態(2)

黒島碩人, 緒方裕子, 大河内博, 床次眞司, 反町篤行, 細田正洋, 片岡淳

大気環境学会年会講演要旨集 55th 491 2014年08月

J-GLOBAL
OISTER・すざくによる2FGL J2339.6‐0532の観測

谷津陽一, 橘優太郎, 大内遥河, 有元誠, 斉藤嘉彦, 河合誠之, 片岡淳, 高橋洋介, 柴田晋平, 関口和寛, 黒田大介, 花山秀和, 磯貝瑞希, 渡辺誠, 橋本修, 諸隈智貴, 高橋英則, 舘内謙, 村田勝寛, 永山貴宏, 面高俊宏, 吉田道利, ALI Gamal B, MOHAMED A. Essam, 秋田谷洋, 高橋隼, 奥村真一郎, 野上大作, 大朝由美子

日本天文学会年会講演予稿集 2014 75 2014年08月

J-GLOBAL
Development of a prototype of time-over-threshold based small animal PET scanner

K. Shimazoe, H. Takahashi, K. Kamada, A. Yoshikawa, K. Kumagai, J. Kataoka, S. Itoh, H. Sato, Y. Usuki

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 753 84 - 90 2014年07月

　概要を見る

A time-over-threshold (ToT)-based positron emission tomography (TODPET) scanner was designed and fabricated. The PET scanner consisted of eight block detectors, each of which is composed of a 12 12 array of 2 210 mm 3 Pr:LuAG crystals individually coupled with a 12 12 UV-enhanced avalanche photodiode (APD) array. The APDs were individually read out using a custom-designed time-over-threshold application-specific integrated circuit (ASIC) and field-programmable gate array (FPGA) readout system. The PET scanner has an energy resolution of 10% and a time resolution of 4.2 ns. A spatial resolution of 1.17 mm (FWHM) was demonstrated in the initial results. © 2014 Elsevier B.V.

DOI
29pTK-6 ASTRO-H衛星搭載硬X線検出器(HXI)の開発状況(29pTK X線・γ線(ASTRO-H,すざく),宇宙線・宇宙物理領域)

川原田円, 国分紀秀, 中澤知洋, 佐藤悟朗, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 佐藤理江, 原山淳, 高橋忠幸, 高橋弘充, 武田伸一郎, 田島宏康, 田中孝明, 寺田幸功, 深沢泰司, 牧島一夫, 水野恒史, 谷津陽一, 山岡和貴, 湯浅孝行, 渡辺伸, Laurent Philippe, Lebrun Francois, Limousin Olivier, HXIチーム

日本物理学会講演概要集 69 ( 1 ) 129 - 129 2014年03月

CiNii
29pTK-8 ASTRO-H衛星搭載軟ガンマ線検出器の開発状況(29pTK X線・γ線(ASTRO-H,すざく),宇宙線・宇宙物理領域)

太田方之, 田島宏康, 深沢泰司, 渡辺伸, 内山秀樹, 内山泰伸, 榎戸輝揚, 大野雅功, 小高裕和, 片岡淳, 川原田円, 国分紀秀, 佐藤悟朗, 佐藤理江, 高橋忠幸, 高橋弘充, 武田伸一郎, 田代信, 田中孝明, 寺田幸功, 中澤知洋, 中森健之, 野田博文, 林克洋, 原山淳, Blandford Roger, 牧島一夫, Madejski Grzegorz, 水野恒史, 谷津陽一, 山岡和貴, 湯浅孝行, 米徳大輔, Laurent Philippe, Limousin Olivier, Lebrun Francois, SGDチーム

日本物理学会講演概要集 69 ( 1 ) 129 - 129 2014年03月

CiNii
MPPCを用いた広角指向性を持つ簡易放射線検出器の開発

中森健之, 武部瑞希, 郡司修一, 佐藤浩樹, 伊藤繁記, 吉野将生, 薄善行, 片岡淳

応用物理学会春季学術講演会講演予稿集(CD-ROM) 61st ROMBUNNO.18A-F1-3 2014年03月

J-GLOBAL
ASTRO‐H衛星搭載硬X線撮像検出器(HXI)開発の現状

佐藤悟朗, 国分紀秀, 中澤知洋, 高橋忠幸, 渡辺伸, 川原田円, 太田方之, 佐藤理江, 武田伸一郎, 小高裕和, 湯浅孝行, 林克洋, 原山淳, 牧島一夫, 野田博文, 片岡淳, 谷津陽一, 中森健之, 内山秀樹, 田島宏康, 山岡和貴, 深沢泰司, 水野恒史, 高橋弘充, 大野雅功, 寺田幸功, 榎戸輝揚, 田中孝明, 内山泰伸, LIMOUSIN Olivier, LAURENT Philippe, LEBRUN Francois

日本天文学会年会講演予稿集 2014 275 2014年02月

J-GLOBAL
18pSB-3 CTA報告75 : 全体報告(18pSB 高エネルギーガンマ線(CTA,MAGIC),宇宙線・宇宙物理領域)

手嶋政廣, 窪秀利, 戸谷友則, 浅野勝晃, 井岡邦仁, 井川大地, 石尾一馬, 井上進, 井上剛志, 井上芳幸, 猪自祐介, 内山泰伸, 梅津陽平, 大石理子, 大岡秀行, 大平豊, 荻野桃子, 奥村曉, 小野祥弥, 折戸玲子, 加賀谷美佳, 格和純, 片岡淳, 片桐秀明, 河島孝則, 川中宣太, 木坂将大, 櫛田淳子, 郡司修一, 郡和範, 小島拓実, 小谷一仁, 小山志勇, 今野裕介, 齋藤隆之, 齋藤浩二, 榊直人, 佐野栄俊, 澤田真理, 柴田徹, 高橋慶太郎, 高橋弘充, 高橋光成, 高見一, 田島宏康, 立原研悟, 田中周太, 田中孝明, 田中真伸, 田中康之, 千川道幸, 長紀仁, 辻本晋平, 土屋優悟, 坪根義雄, 鶴剛, 寺田幸功, 當真賢二, 門叶冬樹, 友野弥生, 鳥居和史, 内藤統也, 中嶋大輔, 長瀧重博, 中森健之, 中山和則, 永吉勤, 西嶋恭司, 野田浩司, 畑中謙一郎, 花畑義隆, 早川貴敬, 林田将明, 原敏, 馬場彩, 日高直哉, 広谷幸一, 平井亘, 深沢泰司, 深見哲志, 福井康雄, 福田達哉, 藤田裕, 増田周, 松岡俊介, 松本浩典, 水野恒史, 村石浩, 村瀬孔大, 森浩二, 柳田昭平, 山崎了, 山本常夏, 山本宏昭, 吉池智史, 吉越貴紀, 吉田篤正, 吉田龍生, 李兆衡

日本物理学会講演概要集 69.2.1 32 2014年

DOI CiNii
ASTRO-H衛星搭載硬X線軟ガンマ線検出器におけるBGOアクティブシールドの開発状況

大野雅功, 徳田伸矢, 中村竜, 高橋弘充, 深沢泰司, 村上浩章, 小林翔悟, 櫻井壮希, 笹野理, 鳥井俊輔, 中澤和洋, 牧島一夫, 山岡和貴, 田島宏康, 内山秀樹, 佐藤理江, 萩野浩一, 湯浅孝行, 佐藤悟朗, 渡辺伸, 国分紀秀, 高橋忠幸, 森國城, 谷津陽一, 片岡淳, 齋藤龍彦, 吉野将生, 中森健之

日本物理学会講演概要集 69 ( 1 ) 2014年

J-GLOBAL
30aTK-12 ガンマ線バースト偏光観測衛星TSUBAMEの打ち上げ(30aTK X線・γ線,宇宙線・宇宙物理領域)

谷津陽一, 中森健之, 久保信, 伊藤慶, 栗田信, 有元誠, 河合誠之, 松下将典, 松永三郎, 木村真一, 片岡淳

日本物理学会講演概要集 69 ( 0 ) 2014年

CiNii
大面積MPPC array を用いた放射線検出器の最前線

片岡淳

放射線（応用物理学会・放射線分科会） 39 ( 3 ) 117 - 126 2014年
Handy Compton camera using 3D position-sensitive scintillators coupled with large-area monolithic MPPC arrays

J. Kataoka, A. Kishimoto, T. Nishiyama, T. Fujita, K. Takeuchi, T. Kato, T. Nakamori, S. Ohsuka, S. Nakamura, M. Hirayanagi, S. Adachi, T. Uchiyama, K. Yamamoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 732 403 - 407 2013年12月 [査読有り]

　概要を見る

The release of radioactive isotopes (mainly Cs-137, Cs-134 and till) from the crippled Fukushima Daiichi Nuclear Plant remains a serious problem in japan. To help identify radiation hotspots and ensure effective decontamination operation, we are developing a novel Compton camera weighting only 1 kg and measuring just similar to 10 cm(2) in size. Despite its compactness, the camera realizes a wide 180 degrees field of vision with a sensitivity about 50 times superior to other cameras being tested in Fukushima. We expect that a hotspot producing a 5 mu Sv/h dose at a distance of 3 m can be imaged every 10 s, with angular resolution better than 10 degrees (FWHM). The 3D position sensitive scintillators and thin monolithic MPPC arrays are the key technologies developed here. By measuring the pulse height ratio of MPPC-arrays coupled at both ends of a Ce:GAGG scintillator block, the depth of interaction (DOI) is obtained for incident gamma rays as well as the usual 2D positions, with accuracy better than 2 mm. By using two identical 10 mm cubic Ce:GAGG scintillators as a scatterer and an absorber, we confirmed that the 3D configuration works well as a high resolution gamma camera, and also works as spectrometer achieving typical energy resolution of 9.8% (FWHM) for 662 keV gamma rays. We present the current status of the prototype camera (weighting 1.5 kg and measuring 8.5 x 14 x 16 cm(3) in size) being fabricated by Hamamatsu Photonics K. K. Although the camera still operates in non-DOI mode, angular resolution as high as 14 degrees (FWHM) was achieved with an integration time of 30s for the assumed hotspot described above. (C) 2013 Elsevier B.V. All tights reserved.

DOI
SUZAKU OBSERVATIONS OF THE DIFFUSE X-RAY EMISSION ACROSS THE FERMI BUBBLES' EDGES

J. Kataoka, M. Tahara, T. Totani, Y. Sofue, L. Stawarz, Y. Takahashi, Y. Takeuchi, H. Tsunemi, M. Kimura, Y. Takei, C. C. Cheung, Y. Inoue, T. Nakamori

ASTROPHYSICAL JOURNAL 779 ( 1 ) 57 - 72 2013年12月 [査読有り]

　概要を見る

We present Suzaku X-ray observations along two edge regions of the Fermi Bubbles, with eight similar or equal to 20 ks pointings across the northern part of the North Polar Spur (NPS) surrounding the north bubble and six across the southernmost edge of the south bubble. After removing compact X-ray features, diffuse X-ray emission is clearly detected and is well reproduced by a three-component spectral model consisting of unabsorbed thermal emission (temperature kT similar or equal to 0.1 keV) from the Local Bubble, absorbed kT similar or equal to 0.3 keV thermal emission related to the NPS and/or Galactic halo (GH), and a power-law component at a level consistent with the cosmic X-ray background. The emission measure (EM) of the 0.3 keV plasma decreases by similar or equal to 50% toward the inner regions of the northeast bubble, with no accompanying temperature change. However, such a jump in the EM is not clearly seen in the south bubble data. While it is unclear whether the NPS originates from a nearby supernova remnant or is related to previous activity within or around the Galactic center, our Suzaku observations provide evidence that suggests the latter scenario. In the latter framework, the presence of a large amount of neutral matter absorbing the X-ray emission as well as the existence of the kT similar or equal to 0.3 keV gas can be naturally interpreted as a weak shock driven by the bubbles' expansion in the surrounding medium, with velocity v(exp) similar or equal to 300 km s(-1) (corresponding to shock Mach number M similar or equal to 1.5), compressing the GH gas to form the NPS feature. We also derived an upper limit for any non-thermal X-ray emission component associated with the bubbles and demonstrate that, in agreement with the aforementioned findings, the non-thermal pressure and energy estimated from a one-zone leptonic model of its broadband spectrum, are in rough equilibrium with that of the surrounding thermal plasma.

DOI
Handy Compton camera using 3D position-sensitive scintillators coupled with large-area monolithic MPPC arrays

J. Kataoka, A. Kishimoto, T. Nishiyama, T. Fujita, K. Takeuchi, T. Kato, T. Nakamori, S. Ohsuka, S. Nakamura, M. Hirayanagi, S. Adachi, T. Uchiyama, K. Yamamoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 732 403 - 407 2013年12月

　概要を見る

The release of radioactive isotopes (mainly Cs-137, Cs-134 and till) from the crippled Fukushima Daiichi Nuclear Plant remains a serious problem in japan. To help identify radiation hotspots and ensure effective decontamination operation, we are developing a novel Compton camera weighting only 1 kg and measuring just similar to 10 cm(2) in size. Despite its compactness, the camera realizes a wide 180 degrees field of vision with a sensitivity about 50 times superior to other cameras being tested in Fukushima. We expect that a hotspot producing a 5 mu Sv/h dose at a distance of 3 m can be imaged every 10 s, with angular resolution better than 10 degrees (FWHM). The 3D position sensitive scintillators and thin monolithic MPPC arrays are the key technologies developed here. By measuring the pulse height ratio of MPPC-arrays coupled at both ends of a Ce:GAGG scintillator block, the depth of interaction (DOI) is obtained for incident gamma rays as well as the usual 2D positions, with accuracy better than 2 mm. By using two identical 10 mm cubic Ce:GAGG scintillators as a scatterer and an absorber, we confirmed that the 3D configuration works well as a high resolution gamma camera, and also works as spectrometer achieving typical energy resolution of 9.8% (FWHM) for 662 keV gamma rays. We present the current status of the prototype camera (weighting 1.5 kg and measuring 8.5 x 14 x 16 cm(3) in size) being fabricated by Hamamatsu Photonics K. K. Although the camera still operates in non-DOI mode, angular resolution as high as 14 degrees (FWHM) was achieved with an integration time of 30s for the assumed hotspot described above. (C) 2013 Elsevier B.V. All tights reserved.

DOI
SUZAKU OBSERVATIONS OF THE DIFFUSE X-RAY EMISSION ACROSS THE FERMI BUBBLES' EDGES

J. Kataoka, M. Tahara, T. Totani, Y. Sofue, L. Stawarz, Y. Takahashi, Y. Takeuchi, H. Tsunemi, M. Kimura, Y. Takei, C. C. Cheung, Y. Inoue, T. Nakamori

ASTROPHYSICAL JOURNAL 779 ( 1 ) 57 - 72 2013年12月

　概要を見る

We present Suzaku X-ray observations along two edge regions of the Fermi Bubbles, with eight similar or equal to 20 ks pointings across the northern part of the North Polar Spur (NPS) surrounding the north bubble and six across the southernmost edge of the south bubble. After removing compact X-ray features, diffuse X-ray emission is clearly detected and is well reproduced by a three-component spectral model consisting of unabsorbed thermal emission (temperature kT similar or equal to 0.1 keV) from the Local Bubble, absorbed kT similar or equal to 0.3 keV thermal emission related to the NPS and/or Galactic halo (GH), and a power-law component at a level consistent with the cosmic X-ray background. The emission measure (EM) of the 0.3 keV plasma decreases by similar or equal to 50% toward the inner regions of the northeast bubble, with no accompanying temperature change. However, such a jump in the EM is not clearly seen in the south bubble data. While it is unclear whether the NPS originates from a nearby supernova remnant or is related to previous activity within or around the Galactic center, our Suzaku observations provide evidence that suggests the latter scenario. In the latter framework, the presence of a large amount of neutral matter absorbing the X-ray emission as well as the existence of the kT similar or equal to 0.3 keV gas can be naturally interpreted as a weak shock driven by the bubbles' expansion in the surrounding medium, with velocity v(exp) similar or equal to 300 km s(-1) (corresponding to shock Mach number M similar or equal to 1.5), compressing the GH gas to form the NPS feature. We also derived an upper limit for any non-thermal X-ray emission component associated with the bubbles and demonstrate that, in agreement with the aforementioned findings, the non-thermal pressure and energy estimated from a one-zone leptonic model of its broadband spectrum, are in rough equilibrium with that of the surrounding thermal plasma.

DOI
21pSP-10 ガンマ線バースト硬X線偏光観測衛星TSUBAMEフライトモデルの開発(X線・γ線,宇宙線・宇宙物理領域)

谷津陽一, 栗田真, 伊藤慶, 有元誠, 常世田和樹, 河合誠之, 神谷崇志, 喜多村章悟, 松永三郎, 片岡淳, 中森健之, 久保信, TSUBAMEチーム

日本物理学会講演概要集 68 ( 2 ) 111 - 111 2013年08月

CiNii
21pSP-1 ASTRO-H衛星搭載軟ガンマ線検出器の衛星搭載品開発(X線・γ線,宇宙線・宇宙物理領域)

田島宏康, 深沢泰司, 渡辺伸, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 川原田円, 国分紀秀, 佐藤悟朗, 佐藤理江, 高橋忠幸, 高橋弘充, 武田伸一郎, 田代信, 田中孝明, 田中康之, 寺田幸功, 中澤知洋, 中森健之, 林克洋, Blandford Roger, 牧島一夫, Madejski Grzegorz, 水野恒史, 森國城, 谷津陽一, 山岡和貴, 山田真也, 湯浅孝行, 米徳大輔, Laurent Philippe, Limousin Olivier, Lebrun Frangois, SGDチーム

日本物理学会講演概要集 68 ( 2 ) 110 - 110 2013年08月

CiNii
ASTRO‐H衛星搭載硬X線撮像検出器(HXI)の開発の現状

佐藤悟朗, 国分紀秀, 中澤知洋, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 川原田円, 佐藤理江, 高橋忠幸, 高橋弘充, 武田伸一郎, 田島宏康, 田中孝明, 寺田幸功, 深沢泰司, 牧島一夫, 水野恒史, 谷津陽一, 山岡和貴, 湯浅孝行, 渡辺伸, LIMOUSIN Olivier, LAURENT Philippe, LEBRUN Francois

日本物理学会講演概要集 68 ( 2 ) 110 2013年08月

J-GLOBAL
ASTRO‐H衛星搭載型アクティブシールド系の受け入れ試験及び動作検証

徳田伸矢, 大野雅功, 深澤泰司, 高橋弘充, 中村竜, 鳥井俊輔, 笹野理, 村上浩章, 中澤知洋, 牧島一夫, 林克洋, 佐藤理江, 渡辺伸, 湯浅孝行, 国分紀秀, 内山秀樹, 片岡淳, 田島宏康, 山岡和貴, 谷津陽一, 中森健之, 米徳大輔

日本天文学会年会講演予稿集 2013 293 2013年08月

J-GLOBAL
ASTRO‐H衛星搭載硬X線撮像検出器(HXI)の現状~FM製造の現状と予想性能~

中澤知洋, 国分紀秀, 川原田円, 佐藤悟朗, 牧島一夫, 渡辺伸, 高橋忠幸, 佐藤理江, 太田方之, 小高裕和, 武田伸一郎, 湯浅孝行, 中森健之, 片岡淳, 谷津陽一, 内山秀樹, 田島宏康, 山岡和貴, 深沢泰司, 水野恒史, 大野雅功, 高橋弘充, 寺田幸功, 榎戸輝揚, 田中孝明, 内山泰伸, LIMOUSIN Olivier, LAURENT Philippe, LEBRUN Francois

日本天文学会年会講演予稿集 2013 293 2013年08月

J-GLOBAL
29pEA-5 すざく衛星によるCentaurus A電波ローブのX線観測(29pEA 領域2,地球電磁気・地球惑星圏学会,日本天文学会合同プラズマ宇宙物理(3学会合同セッション:粒子加速,加熱,相対論的プラズマ),領域2(プラズマ基礎・プラズマ科学・核融合プラズマ・プラズマ宇宙物理))

田中康之, 深沢泰司, 片岡淳, 高橋忠幸, 竹井洋, 竹内勇人, Stawarz L., Majejski G., O'Sullivan S. P., Cheung C. C., Feain I. J., Gandhi P., Hardcastle M. J., Ostrowski M., Reville B., Siemiginowska A., Simionescu A., Werner N.

日本物理学会講演概要集 68 ( 1 ) 308 - 308 2013年03月

CiNii
28pBE-2 宇宙硬X線検出器PoGOLite気球実験の地上較正試験(28pBE X線・γ線,宇宙線・宇宙物理領域)

河野貴文, 高橋弘充, 水野恒史, 深沢泰司, 釜江常好, 田島宏康, 片岡淳, 高橋忠幸, 河合誠之, Axelsson M., Jackson M., Kiss M., Klamra W., Kole M., Larsson S., Moretti E., Pearce M., Ryde F., Rydstrom S., Olofsson G., Floren H-G., Madejski G., Varner G., PoGOLiteチーム

日本物理学会講演概要集 68 ( 1 ) 137 - 137 2013年03月

CiNii
Astro‐H衛星搭載軟ガンマ線検出器の開発(2012年度後半)

水野恒史, 田島宏康, 深沢泰司, 渡辺伸, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 川原田円, 国分紀秀, 佐藤悟朗, 佐藤理江, 高橋忠幸, 高橋弘充, 武田伸一郎, 田代信, 田中孝明, 寺田幸功, 中澤知洋, 中森健之, BLANDFORD Roger, 牧島一夫, MADEJSKI Grzegorz, 森國城, 谷津陽一, 山田真也, 湯浅孝行, 米徳大輔, LAURENT Philippe, LIMOUSIN Olivier, LEBRUN Francois

日本物理学会講演概要集 68 ( 1 ) 134 2013年03月

J-GLOBAL
ASTRO‐H衛星搭載BGOアクティブシールドの信号処理におけるデジタルフィルタの改良

後藤国広, 松岡正之, 徳田伸矢, 高橋弘充, 大野雅功, 深沢泰司, 湯浅孝行, 佐藤悟朗, 渡辺伸, 国分紀秀, 高橋忠幸, 鳥井俊輔, 中澤知洋, 齋藤龍彦, 中森健之, 片岡淳, 田島宏康

日本天文学会年会講演予稿集 2013 277 2013年02月

J-GLOBAL
ASTRO‐H衛星搭載装置のアクティブシールド用BGO試験の現状(2)

西田瑛量, 牧島一夫, 中澤知洋, 内山秀樹, 笹野理, 村上浩章, 佐藤理江, 山岡和貴, 深澤泰司, 高橋弘充, 林克洋, 徳田伸矢, 片岡淳, 中森健之, 齋藤龍彦, 谷津陽一

日本天文学会年会講演予稿集 2013 277 2013年02月

J-GLOBAL
Development of a time over threshold based pet detector

Kenji Shimazoe, Hiroyuki Takahashi, Kei Kamada, Yoshiyuki Usuki, Masao Yoshino, Jun Kataoka, Takayuki Yanagida, Akira Yoshikawa, Kazuaki Kumagai

Proceedings of the 26th Workshop on Radiation Detectors and Their Uses 74 - 81 2012年12月
TOWARD IDENTIFYING THE UNASSOCIATED GAMMA-RAY SOURCE 1FGL J1311.7-3429 WITH X-RAY AND OPTICAL OBSERVATIONS

J. Kataoka, Y. Yatsu, N. Kawai, Y. Urata, C. C. Cheung, Y. Takahashi, K. Maeda, T. Totani, R. Makiya, H. Hanayama, T. Miyaji, A. Tsai

ASTROPHYSICAL JOURNAL 757 ( 2 ) 176 - 184 2012年10月

　概要を見る

We present deep optical and X-ray follow-up observations of the bright unassociated Fermi-LAT gamma-ray source 1FGL J1311.7-3429. The source was already known as an unidentified EGRET source (3EG J1314-3431, EGR J1314-3417), hence its nature has remained uncertain for the past two decades. For the putative counterpart, we detected a quasi-sinusoidal optical modulation of Delta m similar to 2 mag with a period of similar or equal to 1.5 hr in the Rc, r', and g' bands. Moreover, we found that the amplitude of the modulation and peak intensity changed by greater than or similar to 1 mag and similar to 0.5 mag, respectively, over our total six nights of observations from 2012 March to May. Combined with Swift UVOT data, the optical-UV spectrum is consistent with a blackbody temperature, kT similar or equal to 1 eV and the emission volume radius R-bb similar or equal to 1.5 x 10(4) d(kpc) km (d(kpc) is the distance to the source in units of 1 kpc). In contrast, deep Suzaku observations conducted in 2009 and 2011 revealed strong X-ray flares with a light curve characterized with a power spectrum density of P(f) proportional to f(-2.0 +/- 0.4), but the folded X-ray light curves suggest an orbital modulation also in X-rays. Together with the non-detection of a radio counterpart, and significant curved spectrum and non-detection of variability in gamma-rays, the source may be the second "radio-quiet" gamma-ray emitting millisecond pulsar candidate after 1FGL J2339.7-0531, although the origin of flaring X-ray and optical variability remains an open question.

DOI
TOWARD IDENTIFYING THE UNASSOCIATED GAMMA-RAY SOURCE 1FGL J1311.7-3429 WITH X-RAY AND OPTICAL OBSERVATIONS

J. Kataoka, Y. Yatsu, N. Kawai, Y. Urata, C. C. Cheung, Y. Takahashi, K. Maeda, T. Totani, R. Makiya, H. Hanayama, T. Miyaji, A. Tsai

ASTROPHYSICAL JOURNAL 757 ( 2 ) 176 - 184 2012年10月 [査読有り]

　概要を見る

We present deep optical and X-ray follow-up observations of the bright unassociated Fermi-LAT gamma-ray source 1FGL J1311.7-3429. The source was already known as an unidentified EGRET source (3EG J1314-3431, EGR J1314-3417), hence its nature has remained uncertain for the past two decades. For the putative counterpart, we detected a quasi-sinusoidal optical modulation of Delta m similar to 2 mag with a period of similar or equal to 1.5 hr in the Rc, r', and g' bands. Moreover, we found that the amplitude of the modulation and peak intensity changed by greater than or similar to 1 mag and similar to 0.5 mag, respectively, over our total six nights of observations from 2012 March to May. Combined with Swift UVOT data, the optical-UV spectrum is consistent with a blackbody temperature, kT similar or equal to 1 eV and the emission volume radius R-bb similar or equal to 1.5 x 10(4) d(kpc) km (d(kpc) is the distance to the source in units of 1 kpc). In contrast, deep Suzaku observations conducted in 2009 and 2011 revealed strong X-ray flares with a light curve characterized with a power spectrum density of P(f) proportional to f(-2.0 +/- 0.4), but the folded X-ray light curves suggest an orbital modulation also in X-rays. Together with the non-detection of a radio counterpart, and significant curved spectrum and non-detection of variability in gamma-rays, the source may be the second "radio-quiet" gamma-ray emitting millisecond pulsar candidate after 1FGL J2339.7-0531, although the origin of flaring X-ray and optical variability remains an open question.

DOI
14pSP-6 超小型衛星TSUBAME搭載用ガンマ線バースト検出器の開発(14pSP ガンマ線,宇宙線・宇宙物理領域)

常世田和樹, 栗田真, 林真由美, 川上孝介, 榎本雄太, 戸泉貴裕, 谷津陽一, 河合誠之, 松永三郎, 中森健之, 片岡淳, 久保信

日本物理学会講演概要集 67 ( 2 ) 121 - 121 2012年08月

CiNii
Astro‐H衛星搭載軟ガンマ線検出器の開発

深沢泰司, 田島宏康, 渡辺伸, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 川原田円, 国分紀秀, 佐藤悟朗, 佐藤理江, 高橋忠幸, 高橋弘充, 武田伸一郎, 田代信, 田中孝明, 寺田幸功, 中澤知洋, 中森健之, 牧島一夫, 水野恒史, 森國城, 谷津陽一, 山田真也, 湯浅孝行, 米徳大輔, BLANDFORD Roger, MADEJSKI Grzegorz, LAURENT Philippe, LIMOUSIN Olivier, LEBRUN Francois

日本物理学会講演概要集 67 ( 2 ) 119 2012年08月

J-GLOBAL
ASTRO‐H衛星に搭載するアクティブシールド用BGO試験の現状

西田瑛量, 牧島一夫, 中澤知洋, 内山秀樹, 笹野理, 佐藤理江, 深沢泰司, 高橋弘充, 徳田伸矢, 片岡淳, 中森健之, 谷津陽一

日本天文学会年会講演予稿集 2012 276 2012年08月

J-GLOBAL
Expected radiation damage of reverse-type APDs for the Astro-H mission

J. Kataoka, T. Saito, M. Yoshino, H. Mizoma, T. Nakamori, Y. Yatsu, Y. Ishikawa, Y. Matsunaga, H. Tajima, M. Kokubun, P. G. Edwards

JOURNAL OF INSTRUMENTATION 7 2012年06月

　概要を見る

Scheduled for launch in 2014, Astro-H is the sixth Japanese X-ray astronomy satellite mission. More than 60 silicon avalanche photodiodes (Si-APDs; hereafter APDs) will be used to read out BGO scintillators, which are implemented to generate a veto signal to reduce background contamination for the hard X-ray imager (HXI) and a soft gamma-ray detector (SGD). To date, however, APDs have rarely been used in space experiments. Moreover, strict environmental tests are necessary to guarantee APD performance for missions expected to extend beyond five years. The radiation hardness of APDs, as for most semiconductors, is particularly crucial, since radiation in the space environment is severe. In this paper, we present the results of radiation tests conducted on reverse-type APDs (provided by Hamamatsu Photonics) irradiated by gamma rays (Co-60) and 150 MeV protons. We show that, even under the same 100 Gy dose, high energy protons can cause displacement (bulk) damage in the depletion region and possibly change the activation energy, whereas gamma-ray irradiation is less prone to cause damage, because ionization damage dominates only the surface region. We also present quantitative guidance on how to estimate APD noise deterioration over a range of temperatures and radiation doses. As a practical example, we discuss the expected degradation of the BGO energy threshold for the generation of veto signals, following several years of Astro-H operation in Low Earth Orbit (LEO), and directly compare it to experimental results obtained using a small BGO crystal.

DOI
Expected radiation damage of reverse-type APDs for the Astro-H mission

J. Kataoka, T. Saito, M. Yoshino, H. Mizoma, T. Nakamori, Y. Yatsu, Y. Ishikawa, Y. Matsunaga, H. Tajima, M. Kokubun, P. G. Edwards

JOURNAL OF INSTRUMENTATION 7 2012年06月

　概要を見る

Scheduled for launch in 2014, Astro-H is the sixth Japanese X-ray astronomy satellite mission. More than 60 silicon avalanche photodiodes (Si-APDs; hereafter APDs) will be used to read out BGO scintillators, which are implemented to generate a veto signal to reduce background contamination for the hard X-ray imager (HXI) and a soft gamma-ray detector (SGD). To date, however, APDs have rarely been used in space experiments. Moreover, strict environmental tests are necessary to guarantee APD performance for missions expected to extend beyond five years. The radiation hardness of APDs, as for most semiconductors, is particularly crucial, since radiation in the space environment is severe. In this paper, we present the results of radiation tests conducted on reverse-type APDs (provided by Hamamatsu Photonics) irradiated by gamma rays (Co-60) and 150 MeV protons. We show that, even under the same 100 Gy dose, high energy protons can cause displacement (bulk) damage in the depletion region and possibly change the activation energy, whereas gamma-ray irradiation is less prone to cause damage, because ionization damage dominates only the surface region. We also present quantitative guidance on how to estimate APD noise deterioration over a range of temperatures and radiation doses. As a practical example, we discuss the expected degradation of the BGO energy threshold for the generation of veto signals, following several years of Astro-H operation in Low Earth Orbit (LEO), and directly compare it to experimental results obtained using a small BGO crystal.

DOI
Time over Threshold based digital animal PET (TODPET)

K. Shimazoe, Y. Wang, H. Takahashi, K. Kamada, M. Yoshino, J. Kataoka, Y. Yamaya, T. Yanagida, A. Yoshikawa, K. Kumagai

IEEE Nuclear Science Symposium Conference Record 3267 - 3271 2012年03月

　概要を見る

We have developed Time over Threshold (ToT) based Pr:LuAG-APD PET (TODPET) tomograph with a mixed signal front-end. The tomograph consists of 8 block detectors, each of which is composed of a 12 x 12 array of 2 x 2 x 10mm3Pr:LuAG crystals individually coupled with 12 x 12 UV-enhanced APD arrays. The APDs are individually read out with a custom-designed Time over Threshold ASIC and FPGA readout system. Developed PET tomograph has the energy resolution of 10% and the time resolution of 4.2ns. The 1.76mm spatial resolution (FWHM) is achieved for the first result. © 2011 IEEE.

DOI
27aGC-4 APDによる衛星搭載用大型BGO結晶の測定(27aGC 測定器(III),実験核物理領域)

笹野理, 西岡博之, 奥山翔, 中澤知洋, 牧島一夫, 湯浅孝行, 山田真也, 片岡淳, 深沢泰司, 花畑義隆, 林数馬, 田島宏康, 奥村曉

日本物理学会講演概要集 67 ( 1 ) 110 - 110 2012年03月

CiNii
27aGJ-1 超小型衛星TSUBAME搭載用ガンマ線バースト検出器の開発(27aGJ X線・γ線,宇宙線・宇宙物理領域)

川上孝介, 林真由美, 常世田和樹, 榎本雄太, 戸泉貴裕, 谷津陽一, 河合誠之, 松永三郎, 中森健之, 片岡淳, 久保信

日本物理学会講演概要集 67 ( 1 ) 142 - 142 2012年03月

CiNii
25aGC-8 TOF-PETに向けたMPPC読み出しのための高速LSIの開発及びその評価(25aGC 測定器II・ターゲット,実験核物理領域)

松田英憲, 片岡淳, 池田博一, 中森健之, 三浦大陽, 加藤卓也, 安部貴裕, 石川嘉隆, 里健一, 山村和久, 中村重幸, 川端信行

日本物理学会講演概要集 67 ( 1 ) 2012年03月

CiNii
ASTRO‐H衛星搭載BGOシールド統合試験に向けたアナログ信号処理部の検証

斎藤龍彦, 吉野将生, 溝間青樹, 中森健之, 片岡淳, 川上孝介, 谷津陽一, 後藤国広, 松岡正之, 高橋弘充, 大野雅功, 深沢泰司, 渡辺伸, 国分紀秀, 高橋忠幸, 森國城, 西田瑛量, 笹野理, 鳥井俊輔, 中澤知洋, 牧島一夫, 田島宏康, 内堀幸夫, 北村尚

日本物理学会講演概要集 67 ( 1 ) 138 2012年03月

J-GLOBAL
ASTRO‐H衛星搭載の硬X線・軟ガンマ線検出器シールド部における信号処理用デジタルフィルタ開発

後藤国広, 松岡正之, 高橋弘充, 大野雅功, 深沢泰司, 湯浅孝行, 国分紀秀, 高橋忠幸, 中澤知洋, 吉野将生, 齋藤龍彦, 中森健之, 片岡淳, 田島宏康

日本物理学会講演概要集 67 ( 1 ) 32 2012年03月

J-GLOBAL
硬X線撮像検出器HXIに向けたアクティブシールド機能の検証実験

鳥井俊輔, 笹野理, 西田瑛量, 中澤知洋, 牧島一夫, 後藤国広, 松岡正之, 高橋弘充, 大野雅功, 深沢泰司, 湯浅孝行, 渡辺伸, 国分紀秀, 高橋忠幸, 森國城, 吉野将生, 齋藤龍彦, 溝間青樹, 中森健之, 片岡淳, 田島宏康

日本物理学会講演概要集 67 ( 1 ) 140 2012年03月

J-GLOBAL
Astro‐H衛星搭載軟ガンマ線検出器の開発

田島宏康, 深沢泰司, 渡辺伸, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 川原田円, 国分紀秀, 佐藤悟朗, 高橋忠幸, 高橋弘充, 武田伸一郎, 田代信, 田中孝明, 寺田幸功, 中澤知洋, 中森健之, BLANDFORD Roger, 牧島一夫, MADEJSKI Grzegorz, 水野恒史, 森國城, 谷津陽一, 山岡和貴, 山田真也, 湯浅孝行, 米徳大輔, LAURENT Philippe, LIMOUSIN Olivier, LEBRUN Francois

日本物理学会講演概要集 67 ( 1 ) 139 2012年03月

J-GLOBAL
ASTRO‐H衛星搭載BGOシールド統合試験に向けたアナログ信号処理部の検証

吉野将生, 斎藤龍彦, 溝間青樹, 中森健之, 片岡淳, 後藤国広, 松岡正之, 高橋弘充, 大野雅功, 深澤泰司, 渡辺伸, 国分紀秀, 高橋忠幸, 森國城, 笹野理, 鳥居俊輔, 中澤知洋, 牧島一夫, 川上孝介, 谷津陽一, 田島宏康, 内堀幸夫, 北村尚

日本天文学会年会講演予稿集 2012 287 2012年02月

J-GLOBAL
ASTRO‐H衛星搭載HXI/SGDの電源制御回路部(CPMU)の開発

原山淳, 川原田円, 渡辺伸, 太田方之, 国分紀秀, 高橋忠幸, 田島宏康, 深沢泰司, 中澤知洋, 片岡淳, 寺田幸功

日本天文学会年会講演予稿集 2012 284 2012年02月

J-GLOBAL
26pGJ-3 ASTRO-H衛星搭載硬X線検出器(HXI)の開発の現状(26pGJ X線(ASTRO-Hなど),宇宙線・宇宙物理領域)

川原田円, 中澤知洋, 内山秀樹, 牧島一夫, 深沢泰司, 水野恒史, 高橋弘充, 大野雅功, 片岡淳, 中森健之, 寺田幸功, 国分紀秀, 谷津陽一, 山岡和貴, 田島宏康, 田中孝明, 榎戸輝揚, Philippe Laurent, Francois Lebrun, Olivier Limousin, 佐藤悟朗, 渡辺伸, 田中康之, 太田方之, 湯浅孝行, 小高裕和, 高橋忠幸

日本物理学会講演概要集 67 ( 1 ) 138 - 138 2012年

DOI CiNii
フェルミ・バブルから探る銀河系中心の過去の活動性

片岡淳, 戸谷友則, 井岡邦仁

日本天文学会誌 105 ( 9 ) 542 - 553 2012年

CiNii
BROAD-LINE RADIO GALAXIES OBSERVED WITH FERMI-LAT: THE ORIGIN OF THE GeV gamma-RAY EMISSION

J. Kataoka, L. Stawarz, Y. Takahashi, C. C. Cheung, M. Hayashida, P. Grandi, T. H. Burnett, A. Celotti, S. J. Fegan, P. Fortin, K. Maeda, T. Nakamori, G. B. Taylor, G. Tosti, S. W. Digel, W. McConville, J. Finke, F. D'Ammando

ASTROPHYSICAL JOURNAL 740 ( 1 ) 29 - 44 2011年10月

　概要を見る

We report on a detailed investigation of the gamma-ray emission from 18 broad-line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope data. We confirm the previously reported detections of 3C 120 and 3C 111 in the GeV photon energy range; a detailed look at the temporal characteristics of the observed gamma-ray emission reveals in addition possible flux variability in both sources. No statistically significant gamma-ray detection of the other BLRGs was found, however, in the considered data set. Though the sample size studied is small, what appears to differentiate 3C 111 and 3C 120 from the BLRGs not yet detected in gamma-rays is the particularly strong nuclear radio flux. This finding, together with the indications of the gamma-ray flux variability and a number of other arguments presented, indicates that the GeV emission of BLRGs is most likely dominated by the beamed radiation of relativistic jets observed at intermediate viewing angles. In this paper we also analyzed a comparison sample of high-accretion-rate Seyfert 1 galaxies, which can be considered radio-quiet counterparts of BLRGs, and found that none were detected in gamma-rays. A simple phenomenological hybrid model applied for the broadband emission of the discussed radio-loud and radio-quiet type 1 active galaxies suggests that the relative contribution of the nuclear jets to the accreting matter is >= 1% on average for BLRGs, whereas it is <= 0.1% for Seyfert 1 galaxies.

DOI
Broad-line radio galaxies observed with fermi-lat: The origin of the GeV γ-ray emission

Kataoka, J, Stawarz, Stawarz, Takahashi, Y, Cheung, C. C, Cheung, C. C, Hayashida, M, Grandi, P, Burnett, T. H, Celotti, A, Fegan, S. J, Fortin, P, Maeda, K, Nakamori, T, Taylor, G. B, Tosti, G, Tosti, G, Digel, S. W, McConville, W, McConville, W, Finke, J, D'Ammando, F, D'Ammando, F

Astrophysical Journal 740 ( 1 ) 29 - 44 2011年10月 [査読有り]

　概要を見る

We report on a detailed investigation of the γ-ray emission from 18 broad-line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope data. We confirm the previously reported detections of 3C 120 and 3C 111 in the GeV photon energy range; a detailed look at the temporal characteristics of the observed γ-ray emission reveals in addition possible flux variability in both sources. No statistically significant γ-ray detection of the other BLRGs was found, however, in the considered data set. Though the sample size studied is small, what appears to differentiate 3C 111 and 3C 120 from the BLRGs not yet detected in γ-rays is the particularly strong nuclear radio flux. This finding, together with the indications of the γ-ray flux variability and a number of other arguments presented, indicates that the GeV emission of BLRGs is most likely dominated by the beamed radiation of relativistic jets observed at intermediate viewing angles. In this paper we also analyzed a comparison sample of high-accretion-rate Seyfert 1 galaxies, which can be considered radio-quiet counterparts of BLRGs, and found that none were detected in γ-rays. A simple phenomenological hybrid model applied for the broadband emission of the discussed radio-loud and radio-quiet type 1 active galaxies suggests that the relative contribution of the nuclear jets to the accreting matter is ≥1% on average for BLRGs, whereas it is ≤0.1% for Seyfert 1 galaxies. © 2011. The American Astronomical Society. All rights reserved.

DOI
ASTRO‐H衛星搭載軟ガンマ線検出器(SGD)の開発の現状

渡辺伸, 田島宏康, 深沢泰司, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 川原田円, 国分紀秀, 佐藤悟朗, 高橋弘充, 高橋忠幸, 田代信, 田中孝明, 寺田幸功, 中澤知洋, 中森健之, BLANDFORD Roger, 牧島一夫, MADEJSKI Grzegorz, 水野恒史, 森國城, 谷津陽一, 湯浅孝行, LAURENT Philippe, LIMOUSIN Olivier, LEBRUN Francois

日本物理学会講演概要集 66 ( 2 ) 112 2011年08月

J-GLOBAL
ASTRO‐H衛星搭載BGOアクティブシールドの信号処理におけるデジタルフィルタの最適化

後藤国広, 松岡正之, 高橋弘充, 大野雅功, 深沢泰司, 湯浅孝行, 国分紀秀, 高橋忠幸, 中澤知洋, 吉野将生, 齋藤龍彦, 中森健之, 片岡淳, 田島宏康

日本天文学会年会講演予稿集 2011 305 2011年08月

J-GLOBAL
ASTRO‐H搭載BGOシールド用APDセンサ及びアナログシステムの開発(II)

吉野将生, 齋藤龍彦, 中森健之, 片岡淳, 国分紀秀, 渡辺伸, 大野雅功, 湯浅孝行, 高橋忠幸, 森國城, 西岡博之, 笹野理, 中澤知洋, 牧島一夫, 川上孝介, 谷津陽一, 松岡正之, 後藤国広, 高橋弘充, 深澤泰司, 田島宏康

日本天文学会年会講演予稿集 2011 305 2011年08月

J-GLOBAL
ASTRO‐H HXI/SGD検出器搭載の高電圧電源部の開発

原山淳, 川原田円, 渡辺伸, 太田方之, 国分紀秀, 高橋忠幸, 田島宏康, 深沢泰司, 中澤知洋, 片岡淳, 寺田幸功

日本天文学会年会講演予稿集 2011 303 2011年08月

J-GLOBAL
最先端の要素技術・装置開発研究(29)APDアレー放射線検出器の開発

柳田健之, 吉田彰, 吉田彰, 吉野将生, 片岡淳, 島添健次, 高橋浩之, 鎌田圭, 遠藤貴範, 堤浩輔, 佐藤浩樹, 薄善行

NIRS-R (National Inst. of Radiological Sciences) ( 64 ) 87 - 89 2011年03月

J-GLOBAL
28aGN-10 ASTRO-H衛星搭載軟ガンマ線検出器によるガンマ線バーストの観測(28aGN 素粒子実験領域,実験核物理領域合同素粒子実験核物理測定器合同セッション(DAQ・ビームライン・半導体検出器・カロリメータ),素粒子実験領域)

大野雅功, 渡辺伸, 川原田円, 太田方之, 佐藤有, 国分紀秀, 高橋忠幸, 田島宏康, 田中孝明, 榎戸輝揚, 深沢泰司, 高橋弘充, 花畑義隆, 松岡正之, 中澤知洋, 湯浅孝行, 中島健太, 西岡博之, 牧島一夫, 山岡和貴, 片岡淳, 中森健之, 吉野将生, 齋藤龍彦, 米徳大輔, 寺田幸功, HXI, SGDチーム

日本物理学会講演概要集 66 ( 1 ) 34 - 34 2011年03月

CiNii
硬X線撮像検出器HXIに向けたアクティブシールド機能の検証実験

鳥井俊輔, 中澤知洋, 内山秀樹, 湯浅孝之, 中島健太, 西岡博之, 櫻井壮希, 笹野理, 中野俊男, 牧島一夫, 国分紀秀, 渡辺伸, 高橋忠幸, 斉藤新也, 福山太郎, 佐藤有, 萩野浩一, 大野雅功, 田島宏康, 榎戸輝揚, 片岡淳, 中森健之, 谷津陽一, 深沢泰司

日本物理学会講演概要集 66 ( 1 ) 123 2011年03月

J-GLOBAL
ASTRO‐H衛星搭載軟ガンマ線検出器(SGD)の開発の現状

田中孝明, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 片岡淳, 川原田円, 国分紀秀, 佐藤悟朗, 高橋忠幸, 高橋弘充, 田島宏康, 田代信, 寺田幸功, 中澤知洋, 中森健之, 深沢泰司, BLANDFORD Roger, 牧島一夫, MADEJSKI Grzegorz, 水野恒史, 森國城, 谷津陽一, 山岡和貴, LAURENT Philippe, LIMOUSIN Olivier, LEBRUN Francois, 渡辺伸

日本物理学会講演概要集 66 ( 1 ) 122 2011年03月

J-GLOBAL
ASTRO‐H搭載BGOシールド用APDセンサ及びアナログシステムの開発

齋藤龍彦, 吉野将生, 中森健之, 片岡淳, 国分紀秀, 渡辺伸, 大野雅功, 高橋忠幸, 森國城, 西岡博之, 笹野理, 中澤知洋, 牧島一夫, 谷津陽一, 松岡正之, 高橋弘充, 深澤泰司, 田島宏康

日本物理学会講演概要集 66 ( 1 ) 123 2011年03月

J-GLOBAL
次期X線衛星ASTRO‐Hへ向けたBGO結晶シンチレータのAPD読み出しによる光収集効率の研究

西岡博之, 笹野理, 湯浅孝行, 山田真也, 中澤知洋, 牧島一夫, 深沢泰司, 齋藤龍彦, 吉野将生, 中森健之, 片岡淳, 谷津陽一

日本物理学会講演概要集 66 ( 1 ) 123 2011年03月

J-GLOBAL
次期X線天文衛星ASTRO‐H搭載CdTe半導体検出器における放射化バックグラウンドの評価

佐藤有, 大野雅功, 太田方之, 渡辺伸, 川原田円, 小高裕和, 古関優, 福山太郎, 斎藤新也, 萩野浩一, 国分紀秀, 高橋忠幸, 水野恒史, 平木一至, 林克洋, 西野翔, 道津匡平, 朴寅春, 深沢泰司, 田島宏康, 田中孝明, 榎戸輝揚, 中澤知洋, 内山秀樹, 湯浅孝之, 鳥井俊輔, 西岡博之, 櫻井壮希, 笹野理, 中野俊男, 牧島一夫, 片岡淳, 吉野将生

日本天文学会年会講演予稿集 2011 256 2011年02月

J-GLOBAL
ASTRO‐H搭載BGOシールド用APDセンサ及びアナログシステムの開発

吉野将生, 齋藤龍彦, 中森健之, 片岡淳, 国分紀秀, 渡辺伸, 大野雅功, 高橋忠幸, 森國城, 西岡博之, 笹野理, 中澤知洋, 牧島一夫, 川上孝介, 谷津陽一, 松岡正之, 花畑義隆, 高橋弘充, 深澤泰司, 田島宏康

日本天文学会年会講演予稿集 2011 257 2011年02月

J-GLOBAL
ASTRO‐H搭載硬X線撮像検出器/軟ガンマ線検出器のアクティブシールド部におけるデジタルフィルタの開発

松岡正之, 高橋弘充, 花畑義隆, 深沢泰司, 大野雅功, 国分紀秀, 高橋忠幸, 湯浅孝行, 中澤知洋, 吉野将生, 齋藤龍彦, 中森健之, 片岡淳, 田島宏康

日本天文学会年会講演予稿集 2011 252 2011年02月

J-GLOBAL
Development of an APD-Based PET Module and Preliminary Resolution Performance of an Experimental Prototype Gantry

Jun Kataoka, Hidenori Matsuda, Fumihiko Nishikido, Makoto Koizumi, Hirokazu Ikeda, Masao Yoshino, Takamasa Miura, Satoshi Tanaka, Yoshitaka Ishikawa, Nobuyuki Kawabata, Keiji Shimizu, Yusuke Matsunaga, Shunji Kishimoto, Hidetoshi Kubo, Yoshio Yanagida, Takeshi Nakamori

IEEE TRANSACTIONS ON NUCLEAR SCIENCE 57 ( 5 ) 2448 - 2454 2010年10月 [査読有り]

　概要を見る

The development of a high-resolution Positron Emission Tomography (PET) technique with sub-millimeter spatial resolution, which utilizes newly designed reverse-type APD-arrays, is uderway. All the detector blocks are modularized with the overall dimension of each module, including the APD array, LYSO scintillator matrix and Front-End Circuits (FECs), which are only 30 x 30 x 80 mm(3). Each APD device also has a monolithic 16 x 16 pixel structure with an active area of 1.0 mm(2) per pixel. The FEC includes two identical analog ASICs specifically designed for APDs with a noise characteristic of 560 + 30 e(-)/pF and a timing resolution of 460 ps (rms), respectively. An energy resolution of 13.7 +/- 1.1% (FWHM) with 662 keV gamma-rays was measured using the 16 x 16 arrays. At this stage a pair of module and coincidence circuits has been assembled into an experimental prototype gantry. Spatial resolutions of 0.9, 1.4, and 1.3 mm (FWHM) were obtained from FBP reconstructed images in preliminary experiments with a point source positioned centrally, and 1 and 5 mm off-center, respectively. Comparison with a Monte-Carlo simulation of a fully-designed gantry over a wider range of field-of-view showed good correlation with the experimental data. A simple but conceptual design of a DOI configuration is also proposed as a test example of a future APD-PET scanner.

DOI
Development of an APD-Based PET Module and Preliminary Resolution Performance of an Experimental Prototype Gantry

Jun Kataoka, Hidenori Matsuda, Fumihiko Nishikido, Makoto Koizumi, Hirokazu Ikeda, Masao Yoshino, Takamasa Miura, Satoshi Tanaka, Yoshitaka Ishikawa, Nobuyuki Kawabata, Keiji Shimizu, Yusuke Matsunaga, Shunji Kishimoto, Hidetoshi Kubo, Yoshio Yanagida, Takeshi Nakamori

IEEE TRANSACTIONS ON NUCLEAR SCIENCE 57 ( 5 ) 2448 - 2454 2010年10月

　概要を見る

The development of a high-resolution Positron Emission Tomography (PET) technique with sub-millimeter spatial resolution, which utilizes newly designed reverse-type APD-arrays, is uderway. All the detector blocks are modularized with the overall dimension of each module, including the APD array, LYSO scintillator matrix and Front-End Circuits (FECs), which are only 30 x 30 x 80 mm(3). Each APD device also has a monolithic 16 x 16 pixel structure with an active area of 1.0 mm(2) per pixel. The FEC includes two identical analog ASICs specifically designed for APDs with a noise characteristic of 560 + 30 e(-)/pF and a timing resolution of 460 ps (rms), respectively. An energy resolution of 13.7 +/- 1.1% (FWHM) with 662 keV gamma-rays was measured using the 16 x 16 arrays. At this stage a pair of module and coincidence circuits has been assembled into an experimental prototype gantry. Spatial resolutions of 0.9, 1.4, and 1.3 mm (FWHM) were obtained from FBP reconstructed images in preliminary experiments with a point source positioned centrally, and 1 and 5 mm off-center, respectively. Comparison with a Monte-Carlo simulation of a fully-designed gantry over a wider range of field-of-view showed good correlation with the experimental data. A simple but conceptual design of a DOI configuration is also proposed as a test example of a future APD-PET scanner.

DOI
ASTRO‐H衛星搭載硬X線イメージャー(HXI)の開発の現状(V)

渡辺伸, 国分紀秀, 川原田円, 佐藤悟朗, 大野雅功, 田中康之, 太田方之, 高橋忠幸, 中澤知洋, 牧島一夫, 片岡淳, 中森健之, 田島宏康, 田中孝明, 深沢泰司, 水野恒史, 高橋弘充, 谷津陽一, OLIVIER Limousin, LAURENT Philippe, LEBRUN Francois

日本天文学会年会講演予稿集 2010 226 2010年08月

J-GLOBAL
ASTRO‐H衛星硬X線・軟ガンマ線検出器アクティブシールドの機構開発

中島健太, 中澤知洋, 中野俊男, 西岡博之, 牧島一夫, 花畑義隆, 高橋弘充, 水野恒史, 深沢泰司, 山岡和貴, 田島宏康, 片岡淳, 大野雅功, 国分紀秀, 高橋忠幸, 渡辺伸, 田代信, 寺田幸功

日本天文学会年会講演予稿集 2010 226 2010年08月

J-GLOBAL
12pSL-12 ASTRO-H搭載半導体コンプトンカメラシステムのトリガーロジック及び信号処理ファームウェアの開発(12pSL DAQ・回路・計測,素粒子実験領域)

大野雅功, 佐藤有, 渡辺伸, 川原田円, 太田方之, 田中康之, 小高裕和, 斉藤新也, 佐々木智香子, 福山太郎, 萩野浩一, 国分紀秀, 高橋忠幸, 田島宏康, 田中孝明, 榎戸輝揚, 深沢泰司, 高橋弘充, 花畑義隆, 中澤知洋, 湯浅孝行, 中島健太, 西岡博之, 牧島一夫, 山岡和貴, 片岡淳, 吉野将生, 米徳大輔, 寺田幸功, HXI, SGDチーム

日本物理学会講演概要集 65 ( 2 ) 17 - 17 2010年08月

CiNii
11pSG-2 PoGOLite気球実験のパスファインダーフライト(2) : データ取得システム(11pSG X線・γ線,宇宙線・宇宙物理領域)

松岡正之, 高橋弘充, 米谷光生, 水野恒史, 深沢泰司, 金井義和, 河合誠之, 片岡淳, 釜江常好, 田島宏康, Madejski G., 高橋忠幸, 郡司修一, 湯浅孝行, Pearce M., Jackson M., Kiss M., Mallol P., Bettolo C. Marini, Rydstrom S., PoGOLiteチーム

日本物理学会講演概要集 65 ( 2 ) 81 - 81 2010年08月

CiNii
11aSG-10 超小型衛星TSUBAME搭載用硬X線偏光計の開発(11aSG X線・γ線,宇宙線・宇宙物理領域)

榎本雄太, 川上孝介, 常世田和樹, 戸泉貴裕, 谷津陽一, 河合誠之, 中森健之, 片岡淳, 久保信

日本物理学会講演概要集 65 ( 2 ) 80 - 80 2010年08月

CiNii
PoGOLite気球実験のパスファインダーフライト(1):大気中性子モニター

高橋弘充, 米谷光生, 松岡正之, 水野恒史, 深沢泰司, 金井義和, 河合誠之, 片岡淳, 釜江常好, 田島宏康, MADEJSKI G, 高橋忠幸, 郡司修一, 湯浅孝行, PEARCE M, JACKSON M, KISS M, MALLOL P, MARINI BETTOLO C, RYDSTROEM S, 柳田健之, 藤本裕, 横田有為, 吉川彰, 河口範明, 石津澄人, 福田健太郎, 須山敏尚, 渡辺賢一

日本物理学会講演概要集 65 ( 2 ) 81 2010年08月

J-GLOBAL
ASTRO‐H衛星搭載軟ガンマ線検出器におけるアクティブシールドの効果の評価

佐藤有, 大野雅功, 渡辺伸, 川原田円, 太田方之, 田中康之, 小高裕和, 福山太郎, 齋藤新也, 佐々木智香子, 萩野浩一, 国分紀秀, 高橋忠幸, 田島宏康, 田中孝明, 深沢泰司, 水野恒史, 平木一至, 林克洋, 西野翔, 道津匡平, PARK I, 中澤知洋, 湯浅孝行, 中島健太, 西岡博之, 野田博文, 鳥井俊輔, 牧島一夫, 片岡淳, 吉野将生

日本物理学会講演概要集 65 ( 2 ) 81 2010年08月

J-GLOBAL
フェルミ衛星による活動銀河ジェット観測の新展開

片岡淳ほか

日本天文学会誌 103 486 2010年08月 [査読有り]
ASTRO‐H衛星搭載硬X線・ガンマ線検出器の宇宙線重粒子に対する応答

国分紀秀, 渡辺伸, 太田方之, 佐藤悟郎, 岸下徹一, 勝田隼一郎, 小高裕和, 石川真之介, 古関優, 佐々木智香子, 斎藤新也, 福山太郎, 中澤知洋, 奥村暁, 山田真也, 鳥井俊輔, 中島健太, 片岡淳, 吉野将生, 三浦大陽, 寺田幸功, 原山淳, 中嶋大, 出原寿紘, 内堀幸夫, 北村尚

NIRS-M (Natl Inst Radiol Sci) ( 234 ) 270 - 271 2010年06月

J-GLOBAL
大面積APDアレーの開発と次世代PET技術への展望

片岡淳

放射線（応用物理学会・放射線分科会） 35 ( 4 ) 277 - 287 2010年06月 [査読有り]
gamma-RAY SPECTRAL EVOLUTION OF NGC 1275 OBSERVED WITH FERMI LARGE AREA TELESCOPE

J. Kataoka, L. Stawarz, C. C. Cheung, G. Tosti, E. Cavazzuti, A. Celotti, S. Nishino, Y. Fukazawa, D. J. Thompson, W. F. McConville

ASTROPHYSICAL JOURNAL 715 ( 1 ) 554 - 560 2010年05月

　概要を見る

We report on a detailed investigation of the high-energy gamma-ray emission from NGC 1275, a well-known radio galaxy hosted by a giant elliptical located at the center of the nearby Perseus cluster. With the increased photon statistics, the center of the gamma-ray-emitting region is now measured to be separated by only 0.46 arcmin from the nucleus of NGC 1275, well within the 95% confidence error circle with radius similar or equal to 1.5 arcmin. Early Fermi Large Area Telescope (LAT) observations revealed a significant decade-timescale brightening of NGC 1275 at GeV photon energies, with a flux about 7 times higher than the one implied by the upper limit from previous EGRET observations. With the accumulation of one year of Fermi-LAT all-sky-survey exposure, we now detect flux and spectral variations of this source on month timescales, as reported in this paper. The average > 100 MeV gamma-ray spectrum of NGC 1275 shows a possible deviation from a simple power-law shape, indicating a spectral cutoff around an observed photon energy of epsilon(gamma) = 42.2 +/- 19.6 GeV, with an average flux of F(gamma) = (2.31 +/- 0.13) x 10(-7) photons cm(-2) s(-1) and a power-law photon index, Gamma(gamma) = 2.13 +/- 0.02. The largest gamma-ray flaring event was observed in 2009 April-May and was accompanied by significant spectral variability above epsilon(gamma) greater than or similar to 1-2 GeV. The gamma-ray activity of NGC 1275 during this flare can be described by a hysteresis behavior in the flux versus photon index plane. The highest energy photon associated with the gamma-ray source was detected at the very end of the observation, with the observed energy of epsilon(gamma) = 67.4 GeV and an angular separation of about 2.4 arcmin from the nucleus. In this paper we present the details of the Fermi-LAT data analysis, and briefly discuss the implications of the observed gamma-ray spectral evolution of NGC 1275 in the context of gamma-ray blazar sources in general.

DOI
gamma-RAY SPECTRAL EVOLUTION OF NGC 1275 OBSERVED WITH FERMI LARGE AREA TELESCOPE

J. Kataoka, L. Stawarz, C. C. Cheung, G. Tosti, E. Cavazzuti, A. Celotti, S. Nishino, Y. Fukazawa, D. J. Thompson, W. F. McConville

ASTROPHYSICAL JOURNAL 715 ( 1 ) 554 - 560 2010年05月

　概要を見る

We report on a detailed investigation of the high-energy gamma-ray emission from NGC 1275, a well-known radio galaxy hosted by a giant elliptical located at the center of the nearby Perseus cluster. With the increased photon statistics, the center of the gamma-ray-emitting region is now measured to be separated by only 0.46 arcmin from the nucleus of NGC 1275, well within the 95% confidence error circle with radius similar or equal to 1.5 arcmin. Early Fermi Large Area Telescope (LAT) observations revealed a significant decade-timescale brightening of NGC 1275 at GeV photon energies, with a flux about 7 times higher than the one implied by the upper limit from previous EGRET observations. With the accumulation of one year of Fermi-LAT all-sky-survey exposure, we now detect flux and spectral variations of this source on month timescales, as reported in this paper. The average > 100 MeV gamma-ray spectrum of NGC 1275 shows a possible deviation from a simple power-law shape, indicating a spectral cutoff around an observed photon energy of epsilon(gamma) = 42.2 +/- 19.6 GeV, with an average flux of F(gamma) = (2.31 +/- 0.13) x 10(-7) photons cm(-2) s(-1) and a power-law photon index, Gamma(gamma) = 2.13 +/- 0.02. The largest gamma-ray flaring event was observed in 2009 April-May and was accompanied by significant spectral variability above epsilon(gamma) greater than or similar to 1-2 GeV. The gamma-ray activity of NGC 1275 during this flare can be described by a hysteresis behavior in the flux versus photon index plane. The highest energy photon associated with the gamma-ray source was detected at the very end of the observation, with the observed energy of epsilon(gamma) = 67.4 GeV and an angular separation of about 2.4 arcmin from the nucleus. In this paper we present the details of the Fermi-LAT data analysis, and briefly discuss the implications of the observed gamma-ray spectral evolution of NGC 1275 in the context of gamma-ray blazar sources in general.

DOI
PET装置開発研究の展望(8)APDアレー放射線検出器の開発

鎌田圭, 遠藤貴範, 堤浩輔, 佐藤浩樹, 柳田健之, 片岡淳, 吉川彰, 高橋浩之, 薄善行

NIRS-R (National Inst. of Radiological Sciences) ( 61 ) 66 - 69 2010年03月

J-GLOBAL
20aBP-11 ASTRO-H衛星搭載硬X線・ガンマ線検出器アクティブシールドの開発(III)(20aBP X線・γ線,宇宙線・宇宙物理領域)

佐々木智香子, 国分紀秀, 森國城, 片岡淳, 高橋忠幸, 渡辺伸, HXI SGDチーム

日本物理学会講演概要集 65 ( 1 ) 103 - 103 2010年03月

CiNii
ASTRO‐H衛星搭載硬X線・軟ガンマ線検出器アクティブシールドの開発(I):光読み出し

花畑義隆, 深沢泰司, 山岡和貴, 田島宏康, 片岡淳, 中澤知洋, 高橋弘充, 水野恒史, 大野雅功, 国分紀秀, 高橋忠幸, 渡辺伸, 田代信, 寺田幸功, 佐々木智香子, 中島健太, 水島翼

日本物理学会講演概要集 65 ( 1 ) 103 2010年03月

J-GLOBAL
ASTRO‐H衛星搭載硬X線撮影検出器(HXI)の開発

国分紀秀, 渡辺伸, 太田方之, 佐藤理江, 大野雅功, 田中康之, 高橋忠幸, 中澤知洋, 牧島一夫, 深沢泰司, 水野恒史, 高橋弘充, 片岡淳, 寺田幸功, 山岡和貴, 田島宏康, 田中孝明

日本物理学会講演概要集 65 ( 1 ) 104 2010年03月

J-GLOBAL
Astro‐H衛星搭載軟ガンマ線検出器(SGD)の開発

渡辺伸, 国分紀秀, 太田方之, 大野雅功, 高橋忠幸, 田島宏康, 田中孝明, 深沢泰司, 水野恒史, 高橋弘充, 中澤知洋, 片岡淳, 山岡和貴

日本物理学会講演概要集 65 ( 1 ) 104 2010年03月

J-GLOBAL
ASTRO‐H衛星硬X線・軟ガンマ線検出器アクティブシールドの開発(II):機構開発

中島健太, 中澤知洋, 西岡博之, 牧島一夫, 花畑義隆, 深沢泰司, 山崎和貴, 田島宏康, 片岡淳, 高橋弘充, 水野恒史, 大野雅功, 国分紀秀, 高橋忠幸, 渡辺伸, 田代信, 寺田幸功, 佐々木智香子, 水島翼

日本物理学会講演概要集 65 ( 1 ) 103 2010年03月

J-GLOBAL
Development of wide-band X-ray gamma-ray imagers using reach-through APD arrays

中森健之, 戸泉貴裕, 谷津陽一, 河合誠之, 片岡淳, 石川嘉隆, 河合哲, 川端信行, 松永祐輔, Nakamori Takeshi, Toizumi Takahiro, Yatsu Yoichi, Kawai Nobuyuki, Kataoka Jun, Ishikawa Yoshitaka, Kawai Tetsu, Kawabata Nobuyuki, Matsunaga Yusuke

宇宙航空研究開発機構特別資料: = JAXA Special Publication: The Energetic Cosmos; from Suzaku to ASTRO-H ( 9 ) 440 - 441 2010年02月

　概要を見る

資料番号: AA0064574172レポート番号: JAXA-SP-09-008E

CiNii
次期X線天文衛星ASTRO‐H(ex‐NeXT)搭載硬X線イメージャ(HXI)の開発の現状(IV)

中澤知洋, 牧島一夫, 国分紀秀, 渡辺伸, 高橋忠幸, 深沢泰司, 片岡淳, 寺田幸功, 山岡和貴, 玉川徹, 田島宏康, OLIVIER Limousin, LAURENT Philippe, LEBRUN Francois

日本天文学会年会講演予稿集 2010 252 2010年02月

J-GLOBAL
Searching for the most distant blazars with the Fermi Gamma-ray Space Telescope

Inoue, Y, Inoue, S, Kobayashi, M. A. R, Totani, T, Kataoka, J, Sato, R

Proceedings of the 25th Texas Symposium on Relativistic Astrophysics. December 6-10, 2010. Heidelberg, Germany. Editors: Frank M. Rieger (Chair), Christopher van Eldik and Werner Hofmann. 2010年
Hard X-ray Imager (HXI) for the ASTRO-H mission

M. Kokubun, K. Nakazawa, T. Enoto, Y. Fukazawa, K. Gilmore, J. Kataoka, M. Kawaharada, P. Laurent, F. Lebrun, O. Limousin, K. Makishima, T. Mizuno, K. Mori, T. Nakamori, M. Ohno, M. Ohta, G. Sato, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, Y. Terada, H. Uchiyama, Y. Uchiyama, S. Watanabe, Y. Yatsu, K. Yamaoka

Proceedings of SPIE - The International Society for Optical Engineering 7732 2010年 [査読有り]

　概要を見る

The Hard X-ray Imager (HXI) is one of four detectors on board the ASTRO-H mission (6th Japanese X-ray satellite), which is scheduled to be launched in 2014. Using the hybrid structure composed of double-sided silicon strip detectors and a cadmium telluride double-sided strip detector, the instrument fully covers the energy range of photons collected with the hard X-ray telescope up to 80 keV with a high quantum efficiency. High spatial resolution of 250 μm and an energy resolution of 1-2 keV (FWHM) are both achieved with low noise front-end ASICs. In addition, the thick BGO active shields surrounding the main detector package is a heritage of the successful performance of the Hard X-ray Detector on board the Suzaku satellite. This feature enables the instrument to achieve an extremely high background reduction caused by cosmic-ray particles, cosmic X-ray background, and in-orbit radiation activation. In this paper, we present the detector concept, design, latest results of the detector development, and the current status of the hardware. © 2010 SPIE.

DOI
The Cosmological Evolution of Blazars and the Extragalactic Gamma-Ray Background in the Fermi Era

Yoshiyuki Inoue, Tomonori Totani, Susumu Inoue, Masakazu A, R. Kobayashi, Jun Kataoka, Rie Sato

2009 Fermi Symposium, Washington, D.C., Nov. 2-5, eConf Proceedings C091122 2009年12月

記事・総説・解説・論説等（国際会議プロシーディングズ）

　概要を見る

The latest determination of the extragalactic gamma-ray background (EGRB) 
radiation by Fermi is compared with the theoretical prediction of the blazar 
component by Inoue & Totani (2009; hereafter IT09). The Fermi EGRB spectrum is 
in excellent agreement with IT09, indicating that blazars are the dominant 
component of the EGRB, and contributions from any other sources (e.g., dark 
matter annihilations) are minor. It also indicates that the blazar SED 
(spectral energy distribution) sequence taken into account in IT09 is a valid 
description of mean blazar SEDs. The possible contribution of MeV blazars to 
the EGRB in the MeV band is also discussed. In five total years of 
observations, we predict that Fermi will detect ~1200 blazars all sky down to 
the corresponding sensitivity limit. We also address the detectability of the 
highest-redshift blazars. Updating our model with regard to high-redshift 
evolution based on SDSS quasar data, we show that Fermi may find some blazars 
up to z~6 during the five-year survey. Such blazars could provide a new probe 
of early star and galaxy formation through GeV spectral attenuation signatures 
induced by high-redshift UV background radiation.
SELENE2ローバー搭載用中性子・ガンマ線分光計 I

長谷部信行, 鳥居祥二, 片岡淳, 唐牛譲, 山下直之, 武田侑子, 長岡央, 森田幹雄, 小林進悟, 晴山慎, 三谷烈史, 高島健, 飯島祐一, 小林正規, 荒井朋子, D’USTON Claude, KIM Kyeong Ja, BRUECKNER Johannes

応用物理学会学術講演会講演予稿集 70th ( 1 ) 141 2009年09月

J-GLOBAL
10aSD-4 ASTRO-H衛星搭載BGO読み出し用APDのアナログ回路前置増幅部の開発(X線・γ線,宇宙線・宇宙物理領域)

佐々木智香子, 国分紀秀, 森國城, 片岡淳, 佐藤理江, 高橋忠幸, 渡辺伸

日本物理学会講演概要集 64 ( 2 ) 30 - 30 2009年08月

CiNii
SUZAKU WIDE BAND ANALYSIS OF THE X-RAY VARIABILITY OF TeV BLAZAR Mrk 421 IN 2006

Masayoshi Ushio, Takaaki Tanaka, Grzegorz Madejski, Tadayuki Takahashi, Masaaki Hayashida, Jun Kataoka, Daniel Mazin, Stefan Ruegamer, Rie Sato, Masahiro Teshima, Stefan Wagner, Yuichi Yaji

ASTROPHYSICAL JOURNAL 699 ( 2 ) 1964 - 1972 2009年07月

　概要を見る

We present the results of X-ray observations of the well studied TeV blazar Mrk 421 with the Suzaku satellite in 2006 April 28. During the observation, Mrk 421 was undergoing a large flare and the X-ray flux was variable, decreasing by similar to 50%, from 7.8 x 10(-10) to 3.7 x 10(-10) erg s(-1) cm(-2) in about 6 hr, followed by an increase by similar to 35%. Thanks to the broad bandpass coupled with high sensitivity of Suzaku, we measured the evolution of the spectrum over the 0.4-60 keV band in data segments as short as similar to 1 ks. The data show deviations from a simple power-law model, but also a clear spectral variability. The time-resolved spectra are fitted by a synchrotron model, where the observed spectrum is due to a exponentially cutoff power-law distribution of electrons radiating in uniform magnetic field; this model is preferred over a broken power law. As another scenario, we separate the spectrum into "steady" and "variable" components by subtracting the spectrum in the lowest-flux period from those of other data segments. In this context, the difference ("variable") spectra are all well described by a broken power-law model with photon index Gamma similar to 1.6, breaking at energy epsilon(brk) similar or equal to 3 keV to another photon index Gamma similar to 2.1 above the break energy, differing from each other only by normalization, while the spectrum of the "steady" component is best described by the synchrotron model. We suggest that the rapidly variable component is due to relatively localized shock (Fermi I) acceleration, while the slowly variable ("steady") component is due to the superposition of shocks located at larger distance along the jet, or due to other acceleration process, such as the stochastic acceleration on magnetic turbulence (Fermi II) in the more extended region.

DOI
FERMI/LARGE AREA TELESCOPE BRIGHT GAMMA-RAY SOURCE LIST

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, D. L. Band, G. Barbiellini, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, G. F. Bignami, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, R. Corbet, L. Costamante, S. Cutini, D. S. Davis, C. D. Dermer, A. de Angelis, A. de Luca, F. de Palma, S. W. Digel, M. Dormody, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, E. C. Ferrara, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, S. E. Healey, D. Horan, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, D. Kocevski, M. L. Kocian, N. Komin, F. Kuehn, M. Kuss, J. Lande, L. Latronico, S. -H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. Marelli, M. N. Mazziotta, W. McConville, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, P. L. Nolan, J. P. Norris, E. Nuss, M. Ohno, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, L. Poupard, S. Raino, R. Rando, P. S. Ray, M. Razzano, N. Rea, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, M. S. Shaw, C. Shrader, A. Sierpowska-Bartosik, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, T. E. Stephens, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, O. Tibolla, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, A. Van Etten, N. Vilchez, V. Vitale, A. P. Waite, E. Wallace, P. Wang, K. Watters, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES 183 ( 1 ) 46 - 66 2009年07月

　概要を見る

Following its launch in 2008 June, the Fermi Gamma-ray Space Telescope (Fermi) began a sky survey in August. The Large Area Telescope (LAT) on Fermi in three months produced a deeper and better resolved map of the gamma-ray sky than any previous space mission. We present here initial results for energies above 100 MeV for the 205 most significant (statistical significance greater than similar to 10 sigma) gamma-ray sources in these data. These are the best characterized and best localized point-like (i.e., spatially unresolved) gamma-ray sources in the early mission data.

DOI
FERMI DISCOVERY OF GAMMA-RAY EMISSION FROM NGC 1275

A. A. Abdo, M. Ackermann, M. Ajello, K. Asano, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, A. Celotti, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, L. R. Cominsky, J. Conrad, L. Costamante, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, D. Donato, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, J. Finke, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, M. Georganopoulos, S. Germani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, M. Kadler, T. Kamae, Y. Kanai, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, F. Kuehn, M. Kuss, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. N. Mazziotta, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, A. Y. Rodriguez, R. W. Romani, F. Ryde, H. F. -W. Sadrozinski, R. Sambruna, D. Sanchez, A. Sander, R. Sato, P. M. Saz Parkinson, C. Sgro, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, G. B. Taylor, J. G. Thayer, D. J. Thompson, D. F. Torres, G. Tosti, Y. Uchiyama, T. L. Usher, N. Vilchez, V. Vitale, A. P. Waite, K. S. Wood, T. Ylinen, M. Ziegler, H. D. Aller, M. F. Aller, K. I. Kellermann, Y. Y. Kovalev, Yu. A. Kovalev, M. L. Lister, A. B. Pushkarev

ASTROPHYSICAL JOURNAL 699 ( 1 ) 31 - 39 2009年07月

　概要を見る

We report the discovery of high-energy (E > 100 MeV) gamma-ray emission from NGC 1275, a giant elliptical galaxy lying at the center of the Perseus cluster of galaxies, based on observations made with the Large Area Telescope (LAT) of the Fermi Gamma-ray Space Telescope. The positional center of the gamma-ray source is only approximate to 3' away from the NGC 1275 nucleus, well within the 95% LAT error circle of approximate to 5'. The spatial distribution of gamma-ay photons is consistent with a point source. The average flux and power-law photon index measured with the LAT from 2008 August 4 to 2008 December 5 are F-gamma = (2.10 +/- 0.23) x 10(-7) ph (>100 MeV) cm(-2) s(-1) and Gamma = 2.17 +/- 0.05, respectively. The measurements are statistically consistent with constant flux during the four-month LAT observing period. Previous EGRET observations gave an upper limit of F-gamma < 3.72 x 10(-8) ph (>100 MeV) cm(-2) s(-1) to the gamma-ray flux from NGC 1275. This indicates that the source is variable on timescales of years to decades, and therefore restricts the fraction of emission that can be produced in extended regions of the galaxy cluster. Contemporaneous and historical radio observations are also reported. The broadband spectrum of NGC 1275 is modeled with a simple one-zone synchrotron/synchrotron self-Compton model and a model with a decelerating jet flow.

DOI
EARLY FERMI GAMMA-RAY SPACE TELESCOPE OBSERVATIONS OF THE QUASAR 3C 454.3

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, S. Chaty, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, L. Costamante, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, E. do Couto e Silva, D. Donato, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, W. B. Focke, L. Foschini, M. Frailis, L. Fuhrmann, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, M. L. Kocian, F. Kuehn, M. Kuss, L. Latronico, S. -H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, E. Massaro, M. N. Mazziotta, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, R. Rando, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, F. Rahoui, F. Ryde, H. F. -W. Sadrozinski, R. Sambruna, D. Sanchez, A. Sander, P. M. Saz Parkinson, C. Sgro, M. S. Shaw, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, N. Vilchez, M. Villata, V. Vitale, A. P. Waite, B. L. Winer, K. S. Wood, T. Ylinen, J. A. Zensus, M. Ziegler

ASTROPHYSICAL JOURNAL 699 ( 1 ) 817 - 823 2009年07月

　概要を見る

This is the first report of Fermi Gamma-Ray Space Telescope observations of the quasar 3C 454.3, which has been undergoing pronounced long-term outbursts since 2000. The data from the Large Area Telescope, covering 2008 July 7-October 6, indicate strong, highly variable.-ray emission with an average flux of similar to 3 x 10 (6) photons cm(-2) s(-1), for energies > 100 MeV. The gamma-ray flux is variable, with strong, distinct, symmetrically shaped flares for which the flux increases by a factor of several on a timescale of about 3 days. This variability indicates a compact emission region, and the requirement that the source is optically thin to pair production implies relativistic beaming with Doppler factor delta > 8, consistent with the values inferred from Very Long Baseline Interferometry observations of superluminal expansion (delta similar to 25). The observed gamma-ray spectrum is not consistent with a simple power law, but instead steepens strongly above similar to 2 GeV, and is well described by a broken power law with photon indices of similar to 2.3 and similar to 3.5 below and above the break, respectively. This is the first direct observation of a break in the spectrum of a high-luminosity blazar above 100 MeV, and it is likely direct evidence for an intrinsic break in the energy distribution of the radiating particles. Alternatively, the spectral softening above 2 GeV could be due to gamma-ray absorption via photon-photon pair production on the soft X-ray photon field of the host active galactic nucleus, but such an interpretation would require the dissipation region to be located very close (less than or similar to 100 gravitational radii) to the black hole, which would be inconsistent with the X-ray spectrum of the source.

DOI
BRIGHT ACTIVE GALACTIC NUCLEI SOURCE LIST FROM THE FIRST THREE MONTHS OF THE FERMI LARGE AREA TELESCOPE ALL-SKY SURVEY

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, A. W. Chen, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, W. Collmar, L. R. Cominsky, J. Conrad, L. Costamante, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, E. C. Ferrara, J. Finke, W. B. Focke, L. Foschini, M. Frailis, L. Fuhrmann, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, S. E. Healey, D. Horan, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, M. Kadler, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knoedlseder, M. L. Kocian, F. Kuehn, M. Kuss, J. Lande, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, E. Massaro, M. N. Mazziotta, W. McConville, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, R. Rando, M. Razzano, S. Razzaque, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, M. S. Shaw, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, G. B. Taylor, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, N. Vilchez, M. Villata, V. Vitale, A. P. Waite, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL 700 ( 1 ) 597 - 622 2009年07月

　概要を見る

The first three months of sky-survey operation with the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope reveal 132 bright sources at |b| > 10 degrees with test statistic greater than 100 ( corresponding to about 10 sigma). Two methods, based on the CGRaBS, CRATES, and BZCat catalogs, indicate high-confidence associations of 106 of these sources with known active galactic nuclei (AGNs). This sample is referred to as the LAT Bright AGN Sample (LBAS). It contains two radio galaxies, namely, Centaurus A and NGC 1275, and 104 blazars consisting of 58 flat spectrum radio quasars (FSRQs), 42 BL Lac objects, and 4 blazars with unknown classification. Four new blazars were discovered on the basis of the LAT detections. Remarkably, the LBAS includes 10 high-energy-peaked BL Lacs (HBLs), sources which were previously difficult to detect in the GeV range. Another 10 lower-confidence associations are found. Only 33 of the sources, plus two at |b| < 10 degrees, were previously detected with Energetic Gamma-Ray Experiment Telescope( EGRET), probably due to variability. The analysis of the gamma-ray properties of the LBAS sources reveals that the average GeV spectra of BL Lac objects are significantly harder than the spectra of FSRQs. No significant correlation between radio and peak gamma-ray fluxes is observed. Blazar log N-log S distributions and luminosity functions are constructed to investigate the evolution of the different blazar classes, with positive evolution indicated for FSRQs but none for BL Lacs. The contribution of LAT blazars to the total extragalactic gamma-ray intensity is estimated.

DOI
SUZAKU WIDE BAND ANALYSIS OF THE X-RAY VARIABILITY OF TeV BLAZAR Mrk 421 IN 2006

Masayoshi Ushio, Takaaki Tanaka, Grzegorz Madejski, Tadayuki Takahashi, Masaaki Hayashida, Jun Kataoka, Daniel Mazin, Stefan Ruegamer, Rie Sato, Masahiro Teshima, Stefan Wagner, Yuichi Yaji

ASTROPHYSICAL JOURNAL 699 ( 2 ) 1964 - 1972 2009年07月

　概要を見る

We present the results of X-ray observations of the well studied TeV blazar Mrk 421 with the Suzaku satellite in 2006 April 28. During the observation, Mrk 421 was undergoing a large flare and the X-ray flux was variable, decreasing by similar to 50%, from 7.8 x 10(-10) to 3.7 x 10(-10) erg s(-1) cm(-2) in about 6 hr, followed by an increase by similar to 35%. Thanks to the broad bandpass coupled with high sensitivity of Suzaku, we measured the evolution of the spectrum over the 0.4-60 keV band in data segments as short as similar to 1 ks. The data show deviations from a simple power-law model, but also a clear spectral variability. The time-resolved spectra are fitted by a synchrotron model, where the observed spectrum is due to a exponentially cutoff power-law distribution of electrons radiating in uniform magnetic field; this model is preferred over a broken power law. As another scenario, we separate the spectrum into "steady" and "variable" components by subtracting the spectrum in the lowest-flux period from those of other data segments. In this context, the difference ("variable") spectra are all well described by a broken power-law model with photon index Gamma similar to 1.6, breaking at energy epsilon(brk) similar or equal to 3 keV to another photon index Gamma similar to 2.1 above the break energy, differing from each other only by normalization, while the spectrum of the "steady" component is best described by the synchrotron model. We suggest that the rapidly variable component is due to relatively localized shock (Fermi I) acceleration, while the slowly variable ("steady") component is due to the superposition of shocks located at larger distance along the jet, or due to other acceleration process, such as the stochastic acceleration on magnetic turbulence (Fermi II) in the more extended region.

DOI
FERMI/LARGE AREA TELESCOPE BRIGHT GAMMA-RAY SOURCE LIST

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, D. L. Band, G. Barbiellini, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, G. F. Bignami, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, R. Corbet, L. Costamante, S. Cutini, D. S. Davis, C. D. Dermer, A. de Angelis, A. de Luca, F. de Palma, S. W. Digel, M. Dormody, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, E. C. Ferrara, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, S. E. Healey, D. Horan, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, D. Kocevski, M. L. Kocian, N. Komin, F. Kuehn, M. Kuss, J. Lande, L. Latronico, S. -H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. Marelli, M. N. Mazziotta, W. McConville, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, P. L. Nolan, J. P. Norris, E. Nuss, M. Ohno, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, L. Poupard, S. Raino, R. Rando, P. S. Ray, M. Razzano, N. Rea, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, M. S. Shaw, C. Shrader, A. Sierpowska-Bartosik, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, T. E. Stephens, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, O. Tibolla, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, A. Van Etten, N. Vilchez, V. Vitale, A. P. Waite, E. Wallace, P. Wang, K. Watters, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES 183 ( 1 ) 46 - 66 2009年07月

　概要を見る

Following its launch in 2008 June, the Fermi Gamma-ray Space Telescope (Fermi) began a sky survey in August. The Large Area Telescope (LAT) on Fermi in three months produced a deeper and better resolved map of the gamma-ray sky than any previous space mission. We present here initial results for energies above 100 MeV for the 205 most significant (statistical significance greater than similar to 10 sigma) gamma-ray sources in these data. These are the best characterized and best localized point-like (i.e., spatially unresolved) gamma-ray sources in the early mission data.

DOI
FERMI DISCOVERY OF GAMMA-RAY EMISSION FROM NGC 1275

A. A. Abdo, M. Ackermann, M. Ajello, K. Asano, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, A. Celotti, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, L. R. Cominsky, J. Conrad, L. Costamante, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, D. Donato, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, J. Finke, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, M. Georganopoulos, S. Germani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, M. Kadler, T. Kamae, Y. Kanai, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, F. Kuehn, M. Kuss, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. N. Mazziotta, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, A. Y. Rodriguez, R. W. Romani, F. Ryde, H. F. -W. Sadrozinski, R. Sambruna, D. Sanchez, A. Sander, R. Sato, P. M. Saz Parkinson, C. Sgro, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, G. B. Taylor, J. G. Thayer, D. J. Thompson, D. F. Torres, G. Tosti, Y. Uchiyama, T. L. Usher, N. Vilchez, V. Vitale, A. P. Waite, K. S. Wood, T. Ylinen, M. Ziegler, H. D. Aller, M. F. Aller, K. I. Kellermann, Y. Y. Kovalev, Yu. A. Kovalev, M. L. Lister, A. B. Pushkarev

ASTROPHYSICAL JOURNAL 699 ( 1 ) 31 - 39 2009年07月

　概要を見る

We report the discovery of high-energy (E > 100 MeV) gamma-ray emission from NGC 1275, a giant elliptical galaxy lying at the center of the Perseus cluster of galaxies, based on observations made with the Large Area Telescope (LAT) of the Fermi Gamma-ray Space Telescope. The positional center of the gamma-ray source is only approximate to 3' away from the NGC 1275 nucleus, well within the 95% LAT error circle of approximate to 5'. The spatial distribution of gamma-ay photons is consistent with a point source. The average flux and power-law photon index measured with the LAT from 2008 August 4 to 2008 December 5 are F-gamma = (2.10 +/- 0.23) x 10(-7) ph (>100 MeV) cm(-2) s(-1) and Gamma = 2.17 +/- 0.05, respectively. The measurements are statistically consistent with constant flux during the four-month LAT observing period. Previous EGRET observations gave an upper limit of F-gamma < 3.72 x 10(-8) ph (>100 MeV) cm(-2) s(-1) to the gamma-ray flux from NGC 1275. This indicates that the source is variable on timescales of years to decades, and therefore restricts the fraction of emission that can be produced in extended regions of the galaxy cluster. Contemporaneous and historical radio observations are also reported. The broadband spectrum of NGC 1275 is modeled with a simple one-zone synchrotron/synchrotron self-Compton model and a model with a decelerating jet flow.

DOI
EARLY FERMI GAMMA-RAY SPACE TELESCOPE OBSERVATIONS OF THE QUASAR 3C 454.3

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, S. Chaty, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, L. Costamante, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, E. do Couto e Silva, D. Donato, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, W. B. Focke, L. Foschini, M. Frailis, L. Fuhrmann, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, M. L. Kocian, F. Kuehn, M. Kuss, L. Latronico, S. -H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, E. Massaro, M. N. Mazziotta, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, R. Rando, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, F. Rahoui, F. Ryde, H. F. -W. Sadrozinski, R. Sambruna, D. Sanchez, A. Sander, P. M. Saz Parkinson, C. Sgro, M. S. Shaw, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, N. Vilchez, M. Villata, V. Vitale, A. P. Waite, B. L. Winer, K. S. Wood, T. Ylinen, J. A. Zensus, M. Ziegler

ASTROPHYSICAL JOURNAL 699 ( 1 ) 817 - 823 2009年07月

　概要を見る

This is the first report of Fermi Gamma-Ray Space Telescope observations of the quasar 3C 454.3, which has been undergoing pronounced long-term outbursts since 2000. The data from the Large Area Telescope, covering 2008 July 7-October 6, indicate strong, highly variable.-ray emission with an average flux of similar to 3 x 10 (6) photons cm(-2) s(-1), for energies > 100 MeV. The gamma-ray flux is variable, with strong, distinct, symmetrically shaped flares for which the flux increases by a factor of several on a timescale of about 3 days. This variability indicates a compact emission region, and the requirement that the source is optically thin to pair production implies relativistic beaming with Doppler factor delta > 8, consistent with the values inferred from Very Long Baseline Interferometry observations of superluminal expansion (delta similar to 25). The observed gamma-ray spectrum is not consistent with a simple power law, but instead steepens strongly above similar to 2 GeV, and is well described by a broken power law with photon indices of similar to 2.3 and similar to 3.5 below and above the break, respectively. This is the first direct observation of a break in the spectrum of a high-luminosity blazar above 100 MeV, and it is likely direct evidence for an intrinsic break in the energy distribution of the radiating particles. Alternatively, the spectral softening above 2 GeV could be due to gamma-ray absorption via photon-photon pair production on the soft X-ray photon field of the host active galactic nucleus, but such an interpretation would require the dissipation region to be located very close (less than or similar to 100 gravitational radii) to the black hole, which would be inconsistent with the X-ray spectrum of the source.

DOI
BRIGHT ACTIVE GALACTIC NUCLEI SOURCE LIST FROM THE FIRST THREE MONTHS OF THE FERMI LARGE AREA TELESCOPE ALL-SKY SURVEY

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, A. W. Chen, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, W. Collmar, L. R. Cominsky, J. Conrad, L. Costamante, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, E. C. Ferrara, J. Finke, W. B. Focke, L. Foschini, M. Frailis, L. Fuhrmann, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, S. E. Healey, D. Horan, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, M. Kadler, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knoedlseder, M. L. Kocian, F. Kuehn, M. Kuss, J. Lande, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, E. Massaro, M. N. Mazziotta, W. McConville, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, R. Rando, M. Razzano, S. Razzaque, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, M. S. Shaw, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, G. B. Taylor, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, N. Vilchez, M. Villata, V. Vitale, A. P. Waite, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL 700 ( 1 ) 597 - 622 2009年07月

　概要を見る

The first three months of sky-survey operation with the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope reveal 132 bright sources at |b| > 10 degrees with test statistic greater than 100 ( corresponding to about 10 sigma). Two methods, based on the CGRaBS, CRATES, and BZCat catalogs, indicate high-confidence associations of 106 of these sources with known active galactic nuclei (AGNs). This sample is referred to as the LAT Bright AGN Sample (LBAS). It contains two radio galaxies, namely, Centaurus A and NGC 1275, and 104 blazars consisting of 58 flat spectrum radio quasars (FSRQs), 42 BL Lac objects, and 4 blazars with unknown classification. Four new blazars were discovered on the basis of the LAT detections. Remarkably, the LBAS includes 10 high-energy-peaked BL Lacs (HBLs), sources which were previously difficult to detect in the GeV range. Another 10 lower-confidence associations are found. Only 33 of the sources, plus two at |b| < 10 degrees, were previously detected with Energetic Gamma-Ray Experiment Telescope( EGRET), probably due to variability. The analysis of the gamma-ray properties of the LBAS sources reveals that the average GeV spectra of BL Lac objects are significantly harder than the spectra of FSRQs. No significant correlation between radio and peak gamma-ray fluxes is observed. Blazar log N-log S distributions and luminosity functions are constructed to investigate the evolution of the different blazar classes, with positive evolution indicated for FSRQs but none for BL Lacs. The contribution of LAT blazars to the total extragalactic gamma-ray intensity is estimated.

DOI
Development of large-area, reverse-type APD-arrays for high-resolution medical imaging

J. Kataoka, M. Koizumi, S. Tanaka, H. Ishibashi, T. Nakamori, N. Kawai, H. Ikeda, Y. Ishikawa, N. Kawabata, Y. Matsunaga, S. Kishimoto, H. Kubo

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 604 ( 1-2 ) 323 - 326 2009年06月

　概要を見る

Avalanche photodiodes (APD) offer advantages in terms of weak scintillation detection, fast time response, and magnetic field insensitivity. We have developed new types of large-area, reverse-type APD-arrays specifically designed for high-resolution positron emission tomography (PET). Each device has a monolithic 16 x 16 (or 8 x 8) pixel structure with an active area of 1.0 (or 4.0, 0.25) mm(2) for each pixel. An excellent gain uniformity (<= 10%) and low dark noise (<= 0.3 nA) have been achieved, measured at room temperature. Energy resolution of 7.2% (FWHM) was obtained for the direct detection of 5.9 keV X-rays, while 10.2% (FWHM) was obtained for 662 keV gamma-rays when coupled with a LYSO scintillator matrix. An excellent time resolution of 102 ps (FWHM) was obtained for a monolithic, 3 mm phi APD pixel. These results suggest that APD-arrays could be a promising device for future applications in nuclear medicine. (C) 2009 Elsevier B.V. All rights reserved.

DOI
Development of large-area, reverse-type APD-arrays for high-resolution medical imaging

J. Kataoka, M. Koizumi, S. Tanaka, H. Ishibashi, T. Nakamori, N. Kawai, H. Ikeda, Y. Ishikawa, N. Kawabata, Y. Matsunaga, S. Kishimoto, H. Kubo

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 604 ( 1-2 ) 323 - 326 2009年06月

　概要を見る

Avalanche photodiodes (APD) offer advantages in terms of weak scintillation detection, fast time response, and magnetic field insensitivity. We have developed new types of large-area, reverse-type APD-arrays specifically designed for high-resolution positron emission tomography (PET). Each device has a monolithic 16 x 16 (or 8 x 8) pixel structure with an active area of 1.0 (or 4.0, 0.25) mm(2) for each pixel. An excellent gain uniformity (<= 10%) and low dark noise (<= 0.3 nA) have been achieved, measured at room temperature. Energy resolution of 7.2% (FWHM) was obtained for the direct detection of 5.9 keV X-rays, while 10.2% (FWHM) was obtained for 662 keV gamma-rays when coupled with a LYSO scintillator matrix. An excellent time resolution of 102 ps (FWHM) was obtained for a monolithic, 3 mm phi APD pixel. These results suggest that APD-arrays could be a promising device for future applications in nuclear medicine. (C) 2009 Elsevier B.V. All rights reserved.

DOI
Performance of a multi-anode photomultiplier employing an ultra bi-alkali photo-cathode and rugged dynodes

T. Toizumi, S. Inagawa, T. Nakamori, J. Kataoka, Y. Tsubuku, Y. Yatsu, T. Shimokawabe, N. Kawai, T. Okada, I. Ohtsu

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 604 ( 1-2 ) 168 - 173 2009年06月

　概要を見る

We report on the performance testing of a multi-anode photomultiplier (MAPMT), the R8900-200-M16MOD-UBA, newly developed by Hamamatsu Photonics K.K. Although the R8900 series offers the great advantage of a highly sensitive surface (>=-80% of physical area), the quantum efficiency (Q.E.) was relatively low (at up to 20%). This paper describes two substantial changes we have made to the R8900-200-M16MOD-UBA: (1) improving the Q.E. to the 40% level by employing an ultra bi-alkali (UBA) photocathode and (2) constructing a rugged dynode that can withstand vibration for future use in space. We measured each pixel signal at the single photoelectron level and the signals of scintillation photons by using a 16-pixel plastic scintillator array. Thanks to high Q.E., good energy resolution of 29.9% (FWHM) was obtained for 59.5 keV gamma-rays. We also demonstrated tolerance to vibration up to 17 G(rms) in possible launching vehicles. (C) 2009 Elsevier B.V. All rights reserved.

DOI
Development of a low-noise analog front-end ASIC for APD-PET detectors

M. Koizumi, J. Kataoka, S. Tanaka, H. Ishibashi, N. Kawai, H. Ikeda, Y. Ishikawa, N. Kawabata, Y. Matsunaga, K. Shimizu, H. Kubo

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 604 ( 1-2 ) 327 - 330 2009年06月

　概要を見る

We report on the development of a front-end ASIC for high spatial resolution PET detectors with time-of-flight capability based on LYSO scintillator arrays coupled with position-sensitive avalanche photodiode (APD) arrays. The ASIC is designed based on the open-IP LSI project led by JAXA and realized in TSMC 0.35-mu m CMOS technology. It consists of an 8-channel charge-sensitive amplifier, band-pass filters, differentiators, pulse-height and timing discriminators, and two-channel time-to-amplitude converters. As a result, energy resolution of 9.7% (FWHM) is obtained at 511 keV, with a time resolution below 970 ps (sigma). We will also report on the current status of developing a second-version ASIC designed to have 32-channel analog circuits with improved time resolution. (C) 2009 Elsevier B.V. All rights reserved.

DOI
Development of large-area, reverse-type APD-arrays for high-resolution medical imaging

J. Kataoka, M. Koizumi, S. Tanaka, H. Ishibashi, T. Nakamori, N. Kawai, H. Ikeda, Y. Ishikawa, N. Kawabata, Y. Matsunaga, S. Kishimoto, H. Kubo

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 604 ( 1-2 ) 323 - 326 2009年06月

　概要を見る

Avalanche photodiodes (APD) offer advantages in terms of weak scintillation detection, fast time response, and magnetic field insensitivity. We have developed new types of large-area, reverse-type APD-arrays specifically designed for high-resolution positron emission tomography (PET). Each device has a monolithic 16 x 16 (or 8 x 8) pixel structure with an active area of 1.0 (or 4.0, 0.25) mm(2) for each pixel. An excellent gain uniformity (<= 10%) and low dark noise (<= 0.3 nA) have been achieved, measured at room temperature. Energy resolution of 7.2% (FWHM) was obtained for the direct detection of 5.9 keV X-rays, while 10.2% (FWHM) was obtained for 662 keV gamma-rays when coupled with a LYSO scintillator matrix. An excellent time resolution of 102 ps (FWHM) was obtained for a monolithic, 3 mm phi APD pixel. These results suggest that APD-arrays could be a promising device for future applications in nuclear medicine. (C) 2009 Elsevier B.V. All rights reserved.

DOI
Performance of a multi-anode photomultiplier employing an ultra bi-alkali photo-cathode and rugged dynodes

T. Toizumi, S. Inagawa, T. Nakamori, J. Kataoka, Y. Tsubuku, Y. Yatsu, T. Shimokawabe, N. Kawai, T. Okada, I. Ohtsu

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 604 ( 1-2 ) 168 - 173 2009年06月

　概要を見る

We report on the performance testing of a multi-anode photomultiplier (MAPMT), the R8900-200-M16MOD-UBA, newly developed by Hamamatsu Photonics K.K. Although the R8900 series offers the great advantage of a highly sensitive surface (>=-80% of physical area), the quantum efficiency (Q.E.) was relatively low (at up to 20%). This paper describes two substantial changes we have made to the R8900-200-M16MOD-UBA: (1) improving the Q.E. to the 40% level by employing an ultra bi-alkali (UBA) photocathode and (2) constructing a rugged dynode that can withstand vibration for future use in space. We measured each pixel signal at the single photoelectron level and the signals of scintillation photons by using a 16-pixel plastic scintillator array. Thanks to high Q.E., good energy resolution of 29.9% (FWHM) was obtained for 59.5 keV gamma-rays. We also demonstrated tolerance to vibration up to 17 G(rms) in possible launching vehicles. (C) 2009 Elsevier B.V. All rights reserved.

DOI
Development of a low-noise analog front-end ASIC for APD-PET detectors

M. Koizumi, J. Kataoka, S. Tanaka, H. Ishibashi, N. Kawai, H. Ikeda, Y. Ishikawa, N. Kawabata, Y. Matsunaga, K. Shimizu, H. Kubo

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 604 ( 1-2 ) 327 - 330 2009年06月

　概要を見る

We report on the development of a front-end ASIC for high spatial resolution PET detectors with time-of-flight capability based on LYSO scintillator arrays coupled with position-sensitive avalanche photodiode (APD) arrays. The ASIC is designed based on the open-IP LSI project led by JAXA and realized in TSMC 0.35-mu m CMOS technology. It consists of an 8-channel charge-sensitive amplifier, band-pass filters, differentiators, pulse-height and timing discriminators, and two-channel time-to-amplitude converters. As a result, energy resolution of 9.7% (FWHM) is obtained at 511 keV, with a time resolution below 970 ps (sigma). We will also report on the current status of developing a second-version ASIC designed to have 32-channel analog circuits with improved time resolution. (C) 2009 Elsevier B.V. All rights reserved.

DOI
Development of large-area, reverse-type APD-arrays for high-resolution medical imaging

J. Kataoka, M. Koizumi, S. Tanaka, H. Ishibashi, T. Nakamori, N. Kawai, H. Ikeda, Y. Ishikawa, N. Kawabata, Y. Matsunaga, S. Kishimoto, H. Kubo

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 604 ( 1-2 ) 323 - 326 2009年06月

　概要を見る

Avalanche photodiodes (APD) offer advantages in terms of weak scintillation detection, fast time response, and magnetic field insensitivity. We have developed new types of large-area, reverse-type APD-arrays specifically designed for high-resolution positron emission tomography (PET). Each device has a monolithic 16 x 16 (or 8 x 8) pixel structure with an active area of 1.0 (or 4.0, 0.25) mm(2) for each pixel. An excellent gain uniformity (<= 10%) and low dark noise (<= 0.3 nA) have been achieved, measured at room temperature. Energy resolution of 7.2% (FWHM) was obtained for the direct detection of 5.9 keV X-rays, while 10.2% (FWHM) was obtained for 662 keV gamma-rays when coupled with a LYSO scintillator matrix. An excellent time resolution of 102 ps (FWHM) was obtained for a monolithic, 3 mm phi APD pixel. These results suggest that APD-arrays could be a promising device for future applications in nuclear medicine. (C) 2009 Elsevier B.V. All rights reserved.

DOI
SIMULTANEOUS OBSERVATIONS OF PKS 2155-304 WITH HESS, FERMI, RXTE, AND ATOM: SPECTRAL ENERGY DISTRIBUTIONS AND VARIABILITY IN A LOW STATE

F. Aharonian, A. G. Akhperjanian, G. Anton, U. Barres de Almeida, A. R. Bazer-Bachi, Y. Becherini, B. Behera, K. Bernloehr, C. Boisson, A. Bochow, V. Borrel, E. Brion, J. Brucker, P. Brun, R. Buehler, T. Bulik, I. Buesching, T. Boutelier, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L. M. Chounet, A. C. Clapson, G. Coignet, M. Dalton, M. K. Daniel, I. D. Davids, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Atai, W. Domainko, L. O. C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, F. Fiasson, A. Foerster, G. Fontaine, M. Fuessling, S. Gabici, Y. A. Gallant, L. Gerard, B. Giebels, J. F. Glicenstein, B. Glueck, P. Goret, D. Goehring, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, C. Jahn, I. Jung, K. Katarzynski, U. Katz, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khelifi, D. Keogh, W. Kluzniak, N. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Ona Wilhelmi, K. J. Orford, M. Ostrowski, M. Panter, M. Paz Arribas, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Puehlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. RudaK, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schoeck, R. Schroeder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, M. Sikora, J. L. Skilton, H. Sol, D. Spangler, L. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, A. Szostek, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, C. van Eldik, G. Vasileiadis, C. Venter, L. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Voelk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, M. G. Baring, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, A. W. Chen, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, J. Conrad, L. Costamante, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, E. do Couto e Silva, P. S. Drell, R. Dubois, G. Dubus, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, E. C. Ferrara, P. Fleury, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, M.-H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, D. Horan, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, M. Kadler, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knodlseder, F. Kuehn, M. Kuss, J. Lande, L. Latronico, S.-H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, G. M. Madejski, A. Makeev, M. N. Mazziotta, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, A. Y. Rodriguez, F. Ryde, H. F.-W. Sadrozinski, D. Sanchez, A. Sander, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, M. Shaw, D. A. Smith, G. Spandre, P. Spinelli, J.-L. Starck, M. S. Strickman, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, N. Vilchez, M. Villata, V. Vitale, A. P. Waite, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL LETTERS 696 ( 2 ) L150 - L155 2009年05月

　概要を見る

We report on the first simultaneous observations that cover the optical, X-ray, and high-energy gamma-ray bands of the BL Lac object PKS 2155-304. The gamma-ray bands were observed for 11 days, between 2008 August 25 and 2008 September 6 (MJD 54704-54715), jointly with the Fermi Gamma-ray Space Telescope and the HESS atmospheric Cherenkov array, providing the first simultaneous MeV-TeV spectral energy distribution (SED) with the new generation of gamma-ray telescopes. The ATOM telescope and the RXTE and Swift observatories provided optical and X-ray coverage of the low-energy component over the same time period. The object was close to the lowest archival X-ray and very high energy (VHE; > 100 GeV) state, whereas the optical flux was much higher. The light curves show relatively little (similar to 30%) variability overall when compared to past flaring episodes, but we find a clear optical/VHE correlation and evidence for a correlation of the X-rays with the high-energy spectral index. Contrary to previous observations in the flaring state, we do not find any correlation between the X-ray and VHE components. Although synchrotron self-Compton models are often invoked to explain the SEDs of BL Lac objects, the most common versions of these models are at odds with the correlated variability we find in the various bands for PKS 2155-304.

DOI
Measurement of the Cosmic Ray e(+)+e(-) Spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, G. Bogaert, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, P. Carlson, J. M. Casandjian, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, G. Di Bernardo, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, C. Farnier, C. Favuzzi, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, D. Gaggero, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, D. Grasso, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, D. Kocevski, F. Kuehn, M. Kuss, J. Lande, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. M. Massai, M. N. Mazziotta, W. McConville, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, M. Pohl, T. A. Porter, S. Profumo, S. Raino, R. Rando, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, T. E. Stephens, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, O. Tibolla, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, A. Van Etten, V. Vasileiou, N. Vilchez, V. Vitale, A. P. Waite, E. Wallace, P. Wang, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

PHYSICAL REVIEW LETTERS 102 ( 18 ) 1101 2009年05月

　概要を見る

Designed as a high-sensitivity gamma-ray observatory, the Fermi Large Area Telescope is also an electron detector with a large acceptance exceeding 2 m(2) sr at 300 GeV. Building on the gamma-ray analysis, we have developed an efficient electron detection strategy which provides sufficient background rejection for measurement of the steeply falling electron spectrum up to 1 TeV. Our high precision data show that the electron spectrum falls with energy as E-3.0 and does not exhibit prominent spectral features. Interpretations in terms of a conventional diffusive model as well as a potential local extra component are briefly discussed.

DOI
FERMI/LARGE AREA TELESCOPE DISCOVERY OF GAMMA-RAY EMISSION FROM THE FLAT-SPECTRUM RADIO QUASAR PKS 1454-354

A. A. Abdo, M. Ackermann, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, G. Bogaert, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, J. Conrad, L. Costamante, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, E. do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, C. Farnier, C. Favuzzi, E. C. Ferrara, P. Fleury, W. B. Focke, L. Foschini, M. Frailis, L. Fuhrmann, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, S. E. Healey, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, M. Kadler, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, M. L. Kocian, F. Kuehn, M. Kuss, L. Latronico, S. -H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. Marelli, M. N. Mazziotta, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, E. Nuss, M. Ohno, T. Ohsugi, R. Ojha, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, R. Rando, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, H. F. -W. Sadrozinski, R. Sambruna, D. Sanchez, A. Sander, P. M. Saz Parkinson, C. Sgro, M. S. Shaw, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, D. J. Suson, H. Tajima, H. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, O. Tibolla, D. F. Torres, G. Tosti, A. Tramacere, T. L. Usher, N. Vilchez, V. Vitale, A. P. Waite, P. Wang, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler, P. G. Edwards, M. M. Chester, D. N. Burrows, M. Hauser, S. Wagner

ASTROPHYSICAL JOURNAL 697 ( 1 ) 934 - 941 2009年05月

　概要を見る

We report the discovery by the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope of high-energy gamma-ray (GeV) emission from the flat-spectrum radio quasar PKS 1454-354 (z = 1.424). On 2008 September 4, the source rose to a peak flux of (3.5 +/- 0.7) x 10(-6) ph cm(-2) s(-1) (E > 100 MeV) on a timescale of hours and then slowly dropped over the following 2 days. No significant spectral changes occurred during the flare. Fermi/LAT observations also showed that PKS 1454-354 is the most probable counterpart of the unidentified EGRET source 3EG J1500-3509. Multiwavelength measurements performed during the following days (7 September with Swift; 6-7 September with the ground-based optical telescope Automated Telescope for Optical Monitoring; 13 September with the Australia Telescope Compact Array) resulted in radio, optical, UV, and X-ray fluxes greater than archival data, confirming the activity of PKS 1454-354.

DOI
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE VELA PULSAR

A. A. Abdo, M. Ackermann, W. B. Atwood, R. Bagagli, L. Baldini, J. Ballet, D. L. Band, G. Barbiellini, M. G. Baring, J. Bartelt, D. Bastieri, B. M. Baughman, K. Bechtol, F. Bellardi, R. Bellazzini, B. Berenji, D. Bisello, R. D. Blandford, E. D. Bloom, J. R. Bogart, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, F. Camilo, P. A. Caraveo, J. M. Casandjian, M. Ceccanti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, I. Cognard, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, R. Corbet, L. Corucci, S. Cutini, D. S. Davis, M. DeKlotz, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, M. Dormody, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Espinoza, C. Farnier, C. Favuzzi, D. L. Flath, P. Fleury, W. B. Focke, M. Frailis, P. C. C. Friere, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, R. Giannitrapani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, E. V. Gotthelf, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, G. Haller, A. K. Harding, P. A. Hart, R. C. Hartman, E. Hays, G. Hobbs, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, S. Johnston, T. Kamae, G. Kanbach, V. M. Kaspi, H. Katagiri, J. Kataoka, A. Kavelaars, N. Kawai, H. Kelly, M. Kerr, B. Kiziltan, W. Klamra, J. Knodlseder, M. Kramer, F. Kuehn, M. Kuss, J. Lande, D. Landriu, L. Latronico, B. Lee, S. -H. Lee, M. Lemoine-Goumard, M. Livingstone, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, A. G. Lyne, G. M. Madejski, A. Makeev, R. N. Manchester, B. Marangelli, M. Marelli, M. N. Mazziotta, J. E. McEnery, S. McGlynn, M. A. McLaughlin, N. Menon, C. Meurer, P. F. Michelson, T. Mineo, N. Mirizzi, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, M. Mongelli, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, P. L. Nolan, A. Noutsos, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, A. Paccagnella, D. Paneque, J. H. Panetta, D. Parent, M. Pearce, M. Pepe, M. Perchiazzi, M. Pesce-Rollins, L. Pieri, M. Pinchera, F. Piron, T. A. Porter, S. Raino, R. Rando, S. M. Ransom, E. Rapposelli, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, A. Sacchetti, H. F. -W. Sadrozinski, N. Saggini, D. Sanchez, A. Sander, P. M. Saz Parkinson, K. N. Segal, A. Sellerholm, C. Sgro, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, M. Stamatikos, J. -L. Starck, F. W. Stecker, T. E. Stephens, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, A. Tenze, J. B. Thayer, J. G. Thayer, G. Theureau, D. J. Thompson, S. E. Thorsett, L. Tibaldo, O. Tibolla, D. F. Torres, A. Tramacere, M. Turri, T. L. Usher, L. Vigiani, N. Vilchez, V. Vitale, A. P. Waite, P. Wang, K. Watters, P. Weltevrede, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL 696 ( 2 ) 1084 - 1093 2009年05月

　概要を見る

The Vela pulsar is the brightest persistent source in the GeV sky and thus is the traditional first target for new gamma-ray observatories. We report here on initial Fermi Large Area Telescope observations during verification phase pointed exposure and early sky survey scanning. We have used the Vela signal to verify Fermi timing and angular resolution. The high-quality pulse profile, with some 32,400 pulsed photons at E >= 0.03 GeV, shows new features, including pulse structure as fine as 0.3 ms and a distinct third peak, which shifts in phase with energy. We examine the high-energy behavior of the pulsed emission; initial spectra suggest a phase-averaged power-law index of Gamma = 1.51(-0.04)(+0.05) with an exponential cutoff at E-c = 2.9 +/- 0.1 GeV. Spectral fits with generalized cutoffs of the form e(-(E/Ec)b) require b <= 1, which is inconsistent with magnetic pair attenuation, and thus favor outer-magnetosphere emission models. Finally, we report on upper limits to any unpulsed component, as might be associated with a surrounding pulsar wind nebula.

DOI
SIMULTANEOUS OBSERVATIONS OF PKS 2155-304 WITH HESS, FERMI, RXTE, AND ATOM: SPECTRAL ENERGY DISTRIBUTIONS AND VARIABILITY IN A LOW STATE

F. Aharonian, A. G. Akhperjanian, G. Anton, U. Barres de Almeida, A. R. Bazer-Bachi, Y. Becherini, B. Behera, K. Bernloehr, C. Boisson, A. Bochow, V. Borrel, E. Brion, J. Brucker, P. Brun, R. Buehler, T. Bulik, I. Buesching, T. Boutelier, P. M. Chadwick, A. Charbonnier, R. C. G. Chaves, A. Cheesebrough, L. M. Chounet, A. C. Clapson, G. Coignet, M. Dalton, M. K. Daniel, I. D. Davids, B. Degrange, C. Deil, H. J. Dickinson, A. Djannati-Atai, W. Domainko, L. O. C. Drury, F. Dubois, G. Dubus, J. Dyks, M. Dyrda, K. Egberts, D. Emmanoulopoulos, P. Espigat, C. Farnier, F. Feinstein, F. Fiasson, A. Foerster, G. Fontaine, M. Fuessling, S. Gabici, Y. A. Gallant, L. Gerard, B. Giebels, J. F. Glicenstein, B. Glueck, P. Goret, D. Goehring, D. Hauser, M. Hauser, S. Heinz, G. Heinzelmann, G. Henri, G. Hermann, J. A. Hinton, A. Hoffmann, W. Hofmann, M. Holleran, S. Hoppe, D. Horns, A. Jacholkowska, O. C. de Jager, C. Jahn, I. Jung, K. Katarzynski, U. Katz, S. Kaufmann, E. Kendziorra, M. Kerschhaggl, D. Khangulyan, B. Khelifi, D. Keogh, W. Kluzniak, N. Komin, K. Kosack, G. Lamanna, J.-P. Lenain, T. Lohse, V. Marandon, J. M. Martin, O. Martineau-Huynh, A. Marcowith, D. Maurin, T. J. L. McComb, M. C. Medina, R. Moderski, E. Moulin, M. Naumann-Godo, M. de Naurois, D. Nedbal, D. Nekrassov, J. Niemiec, S. J. Nolan, S. Ohm, J.-F. Olive, E. de Ona Wilhelmi, K. J. Orford, M. Ostrowski, M. Panter, M. Paz Arribas, G. Pedaletti, G. Pelletier, P.-O. Petrucci, S. Pita, G. Puehlhofer, M. Punch, A. Quirrenbach, B. C. Raubenheimer, M. Raue, S. M. Rayner, M. Renaud, F. Rieger, J. Ripken, L. Rob, S. Rosier-Lees, G. Rowell, B. RudaK, C. B. Rulten, J. Ruppel, V. Sahakian, A. Santangelo, R. Schlickeiser, F. M. Schoeck, R. Schroeder, U. Schwanke, S. Schwarzburg, S. Schwemmer, A. Shalchi, M. Sikora, J. L. Skilton, H. Sol, D. Spangler, L. Stawarz, R. Steenkamp, C. Stegmann, G. Superina, A. Szostek, P. H. Tam, J.-P. Tavernet, R. Terrier, O. Tibolla, C. van Eldik, G. Vasileiadis, C. Venter, L. Venter, J. P. Vialle, P. Vincent, M. Vivier, H. J. Voelk, F. Volpe, S. J. Wagner, M. Ward, A. A. Zdziarski, A. Zech, A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, M. G. Baring, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, A. W. Chen, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, J. Conrad, L. Costamante, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, E. do Couto e Silva, P. S. Drell, R. Dubois, G. Dubus, D. Dumora, C. Farnier, C. Favuzzi, S. J. Fegan, E. C. Ferrara, P. Fleury, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, M.-H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, D. Horan, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, M. Kadler, T. Kamae, H. Katagiri, J. Kataoka, M. Kerr, J. Knodlseder, F. Kuehn, M. Kuss, J. Lande, L. Latronico, S.-H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, G. M. Madejski, A. Makeev, M. N. Mazziotta, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, A. Y. Rodriguez, F. Ryde, H. F.-W. Sadrozinski, D. Sanchez, A. Sander, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, M. Shaw, D. A. Smith, G. Spandre, P. Spinelli, J.-L. Starck, M. S. Strickman, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, N. Vilchez, M. Villata, V. Vitale, A. P. Waite, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL LETTERS 696 ( 2 ) L150 - L155 2009年05月

　概要を見る

We report on the first simultaneous observations that cover the optical, X-ray, and high-energy gamma-ray bands of the BL Lac object PKS 2155-304. The gamma-ray bands were observed for 11 days, between 2008 August 25 and 2008 September 6 (MJD 54704-54715), jointly with the Fermi Gamma-ray Space Telescope and the HESS atmospheric Cherenkov array, providing the first simultaneous MeV-TeV spectral energy distribution (SED) with the new generation of gamma-ray telescopes. The ATOM telescope and the RXTE and Swift observatories provided optical and X-ray coverage of the low-energy component over the same time period. The object was close to the lowest archival X-ray and very high energy (VHE; > 100 GeV) state, whereas the optical flux was much higher. The light curves show relatively little (similar to 30%) variability overall when compared to past flaring episodes, but we find a clear optical/VHE correlation and evidence for a correlation of the X-rays with the high-energy spectral index. Contrary to previous observations in the flaring state, we do not find any correlation between the X-ray and VHE components. Although synchrotron self-Compton models are often invoked to explain the SEDs of BL Lac objects, the most common versions of these models are at odds with the correlated variability we find in the various bands for PKS 2155-304.

DOI
Measurement of the Cosmic Ray e(+)+e(-) Spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope

A. A. Abdo, M. Ackermann, M. Ajello, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, G. Bogaert, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, P. Carlson, J. M. Casandjian, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, G. Di Bernardo, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, C. Farnier, C. Favuzzi, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, D. Gaggero, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, D. Grasso, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, Y. Hanabata, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, D. Kocevski, F. Kuehn, M. Kuss, J. Lande, L. Latronico, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. M. Massai, M. N. Mazziotta, W. McConville, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, F. Piron, M. Pohl, T. A. Porter, S. Profumo, S. Raino, R. Rando, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, A. Sellerholm, C. Sgro, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, T. E. Stephens, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, O. Tibolla, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, A. Van Etten, V. Vasileiou, N. Vilchez, V. Vitale, A. P. Waite, E. Wallace, P. Wang, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

PHYSICAL REVIEW LETTERS 102 ( 18 ) 1101 2009年05月

　概要を見る

Designed as a high-sensitivity gamma-ray observatory, the Fermi Large Area Telescope is also an electron detector with a large acceptance exceeding 2 m(2) sr at 300 GeV. Building on the gamma-ray analysis, we have developed an efficient electron detection strategy which provides sufficient background rejection for measurement of the steeply falling electron spectrum up to 1 TeV. Our high precision data show that the electron spectrum falls with energy as E-3.0 and does not exhibit prominent spectral features. Interpretations in terms of a conventional diffusive model as well as a potential local extra component are briefly discussed.

DOI
FERMI/LARGE AREA TELESCOPE DISCOVERY OF GAMMA-RAY EMISSION FROM THE FLAT-SPECTRUM RADIO QUASAR PKS 1454-354

A. A. Abdo, M. Ackermann, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, G. Bogaert, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Colafrancesco, J. Conrad, L. Costamante, S. Cutini, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, E. do Couto E Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, C. Farnier, C. Favuzzi, E. C. Ferrara, P. Fleury, W. B. Focke, L. Foschini, M. Frailis, L. Fuhrmann, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, A. K. Harding, R. C. Hartman, M. Hayashida, E. Hays, S. E. Healey, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, W. N. Johnson, M. Kadler, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, M. L. Kocian, F. Kuehn, M. Kuss, L. Latronico, S. -H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, M. Marelli, M. N. Mazziotta, J. E. McEnery, S. McGlynn, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, E. Nuss, M. Ohno, T. Ohsugi, R. Ojha, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, R. Rando, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, H. F. -W. Sadrozinski, R. Sambruna, D. Sanchez, A. Sander, P. M. Saz Parkinson, C. Sgro, M. S. Shaw, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, D. J. Suson, H. Tajima, H. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, O. Tibolla, D. F. Torres, G. Tosti, A. Tramacere, T. L. Usher, N. Vilchez, V. Vitale, A. P. Waite, P. Wang, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler, P. G. Edwards, M. M. Chester, D. N. Burrows, M. Hauser, S. Wagner

ASTROPHYSICAL JOURNAL 697 ( 1 ) 934 - 941 2009年05月

　概要を見る

We report the discovery by the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope of high-energy gamma-ray (GeV) emission from the flat-spectrum radio quasar PKS 1454-354 (z = 1.424). On 2008 September 4, the source rose to a peak flux of (3.5 +/- 0.7) x 10(-6) ph cm(-2) s(-1) (E > 100 MeV) on a timescale of hours and then slowly dropped over the following 2 days. No significant spectral changes occurred during the flare. Fermi/LAT observations also showed that PKS 1454-354 is the most probable counterpart of the unidentified EGRET source 3EG J1500-3509. Multiwavelength measurements performed during the following days (7 September with Swift; 6-7 September with the ground-based optical telescope Automated Telescope for Optical Monitoring; 13 September with the Australia Telescope Compact Array) resulted in radio, optical, UV, and X-ray fluxes greater than archival data, confirming the activity of PKS 1454-354.

DOI
FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE VELA PULSAR

A. A. Abdo, M. Ackermann, W. B. Atwood, R. Bagagli, L. Baldini, J. Ballet, D. L. Band, G. Barbiellini, M. G. Baring, J. Bartelt, D. Bastieri, B. M. Baughman, K. Bechtol, F. Bellardi, R. Bellazzini, B. Berenji, D. Bisello, R. D. Blandford, E. D. Bloom, J. R. Bogart, E. Bonamente, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, F. Camilo, P. A. Caraveo, J. M. Casandjian, M. Ceccanti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, I. Cognard, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, R. Corbet, L. Corucci, S. Cutini, D. S. Davis, M. DeKlotz, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, M. Dormody, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, C. Espinoza, C. Farnier, C. Favuzzi, D. L. Flath, P. Fleury, W. B. Focke, M. Frailis, P. C. C. Friere, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, R. Giannitrapani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, E. V. Gotthelf, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, G. Haller, A. K. Harding, P. A. Hart, R. C. Hartman, E. Hays, G. Hobbs, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, S. Johnston, T. Kamae, G. Kanbach, V. M. Kaspi, H. Katagiri, J. Kataoka, A. Kavelaars, N. Kawai, H. Kelly, M. Kerr, B. Kiziltan, W. Klamra, J. Knodlseder, M. Kramer, F. Kuehn, M. Kuss, J. Lande, D. Landriu, L. Latronico, B. Lee, S. -H. Lee, M. Lemoine-Goumard, M. Livingstone, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, A. G. Lyne, G. M. Madejski, A. Makeev, R. N. Manchester, B. Marangelli, M. Marelli, M. N. Mazziotta, J. E. McEnery, S. McGlynn, M. A. McLaughlin, N. Menon, C. Meurer, P. F. Michelson, T. Mineo, N. Mirizzi, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, M. Mongelli, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, P. L. Nolan, A. Noutsos, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, A. Paccagnella, D. Paneque, J. H. Panetta, D. Parent, M. Pearce, M. Pepe, M. Perchiazzi, M. Pesce-Rollins, L. Pieri, M. Pinchera, F. Piron, T. A. Porter, S. Raino, R. Rando, S. M. Ransom, E. Rapposelli, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, A. Sacchetti, H. F. -W. Sadrozinski, N. Saggini, D. Sanchez, A. Sander, P. M. Saz Parkinson, K. N. Segal, A. Sellerholm, C. Sgro, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, M. Stamatikos, J. -L. Starck, F. W. Stecker, T. E. Stephens, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, A. Tenze, J. B. Thayer, J. G. Thayer, G. Theureau, D. J. Thompson, S. E. Thorsett, L. Tibaldo, O. Tibolla, D. F. Torres, A. Tramacere, M. Turri, T. L. Usher, L. Vigiani, N. Vilchez, V. Vitale, A. P. Waite, P. Wang, K. Watters, P. Weltevrede, B. L. Winer, K. S. Wood, T. Ylinen, M. Ziegler

ASTROPHYSICAL JOURNAL 696 ( 2 ) 1084 - 1093 2009年05月

　概要を見る

The Vela pulsar is the brightest persistent source in the GeV sky and thus is the traditional first target for new gamma-ray observatories. We report here on initial Fermi Large Area Telescope observations during verification phase pointed exposure and early sky survey scanning. We have used the Vela signal to verify Fermi timing and angular resolution. The high-quality pulse profile, with some 32,400 pulsed photons at E >= 0.03 GeV, shows new features, including pulse structure as fine as 0.3 ms and a distinct third peak, which shifts in phase with energy. We examine the high-energy behavior of the pulsed emission; initial spectra suggest a phase-averaged power-law index of Gamma = 1.51(-0.04)(+0.05) with an exponential cutoff at E-c = 2.9 +/- 0.1 GeV. Spectral fits with generalized cutoffs of the form e(-(E/Ec)b) require b <= 1, which is inconsistent with magnetic pair attenuation, and thus favor outer-magnetosphere emission models. Finally, we report on upper limits to any unpulsed component, as might be associated with a surrounding pulsar wind nebula.

DOI
Discovery of Pulsed γ-Rays from the Young Radio Pulsar PSR J1028–5819 with the Fermi Large Area Telescope

Abdo et

The Astrophysical Journal 695 ( 1 ) L72 - L77 2009年04月

DOI
DISCOVERY OF PULSED gamma-RAYS FROM THE YOUNG RADIO PULSAR PSR J1028-5819 WITH THE FERMI LARGE AREA TELESCOPE

A. A. Abdo, M. Ackermann, W. B. Atwood, L. Baldini, J. Ballet, G. Barbiellini, M. G. Baring, D. Bastieri, B. M. Baughman, K. Bechtol, R. Bellazzini, B. Berenji, E. D. Bloom, E. Bonamente, A. W. Borgland, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, J. Conrad, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, D. Donato, M. Dormody, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, C. Farnier, C. Favuzzi, P. Fleury, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, A. K. Harding, M. Hayashida, E. Hays, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, S. Johnston, T. Kamae, H. Katagiri, J. Kataoka, N. Kawai, M. Kerr, J. Knoedlseder, N. Komin, M. Kramer, F. Kuehn, M. Kuss, L. Latronico, S. -H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, A. Makeev, M. Marelli, M. N. Mazziotta, W. McConville, J. E. McEnery, C. Meurer, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, P. L. Nolan, E. Nuss, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, D. Paneque, J. H. Panetta, D. Parent, M. Pepe, M. Pesce-Rollins, F. Piron, T. A. Porter, S. Raino, R. Rando, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, C. Sgro, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J. -L. Starck, M. S. Strickman, D. J. Suson, H. Tajima, H. Takahashi, T. Tanaka, J. B. Thayer, J. G. Thayer, D. J. Thompson, S. E. Thorsett, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, Y. Uchiyama, T. L. Usher, A. Van Etten, N. Vilchez, V. Vitale, A. P. Waite, K. Watters, K. S. Wood, T. Ylinen, M. Ziegler, G. Hobbs, M. Keith, R. N. Manchester, P. Weltevrede

ASTROPHYSICAL JOURNAL LETTERS 695 ( 1 ) L72 - L77 2009年04月

　概要を見る

Radio pulsar PSR J1028-5819 was recently discovered in a high-frequency search (at 3.1 GHz) in the error circle of the Energetic Gamma-Ray Experiment Telescope (EGRET) source 3EG J1027-5817. The spin-down power of this young pulsar is great enough to make it very likely the counterpart for the EGRET source. We report here the discovery of gamma-ray pulsations from PSR J1028-5819 in early observations by the Large Area Telescope (LAT) on the Fermi Gamma-Ray Space Telescope. The gamma-ray light curve shows two sharp peaks having phase separation of 0.460 +/- 0.004, trailing the very narrow radio pulse by 0.200 +/- 0.003 in phase, very similar to that of other known gamma-ray pulsars. The measured gamma-ray flux gives an efficiency for the pulsar of similar to 10-20% (for outer magnetosphere beam models). No evidence of a surrounding pulsar wind nebula is seen in the current Fermi data but limits on associated emission are weak because the source lies in a crowded region with high background emission. However, the improved angular resolution afforded by the LAT enables the disentanglement of the previous COS-B and EGRET source detections into at least two distinct sources, one of which is now identified as PSR J1028-5819.

DOI
28pSH-4 国際宇宙ステーション全天X線監視装置(MAXI)の解析ソフトウエアとデータ処理システム(28pSH X線・γ線,宇宙線・宇宙物理領域)

杉崎睦, 三原健弘, 磯部直樹, 松岡勝, 川崎一義, 上野史郎, 冨田洋, 小浜光洋, 鈴木素子, 石川真木, 足立康樹, 常深博, 宮田恵美, 河合誠之, 片岡淳, 吉田篤正, 山岡和貴, 根来均, 中島基樹, 上田佳宏, 森井幹雄

日本物理学会講演概要集 64 ( 1 ) 92 - 92 2009年03月

CiNii
27aXD-10 フェルミ・ガンマ線宇宙望遠鏡で見た拡散γ線放射(27aXD 宇宙線・宇宙物理領域,素粒子実験領域合同招待講演,宇宙線・宇宙物理領域)

水野恒史, 林克洋, 高橋弘充, 片桐秀明, 深沢泰司, 大杉節, 山崎了, 片岡淳, 河合誠之, 尾崎正伸, 高橋忠幸, 奥村暁, 牧島一夫, 福井康雄, 田島宏康, 釜江常好, Digel Seth, Fermi LAT Colaboration

日本物理学会講演概要集 64 ( 1 ) 87 - 87 2009年03月

CiNii
SUZAKU OBSERVATIONS OF THE EXTREME MeV BLAZAR SWIFT J0746.3+2548

Shin Watanabe, Rie Sato, Tadayuki Takahashi, Jun Kataoka, Greg Madejski, Marek Sikora, Fabrizio Tavecchio, Rita Sambruna, Roger Romani, Philip G. Edwards, Tapio Pursimo

ASTROPHYSICAL JOURNAL 694 ( 1 ) 294 - 301 2009年03月

　概要を見る

We report the Suzaku observations of the high luminosity blazar SWIFT J0746.3+2548 (J0746) conducted in 2005 November. This object, which, with z = 2.979, is the highest redshift source observed in the Suzaku Guaranteed Time Observer period, is likely to show high gamma-ray flux peaking in the MeV range. As a result of the good photon statistics and high signal-to-noise ratio spectrum, the Suzaku observation clearly confirms that J0746 has an extremely hard spectrum in the energy range of 0.3-24 keV, which is well represented by a single power-law with a photon index of Gamma(ph) similar or equal to 1.17 and Galactic absorption. The multiwavelength spectral energy distribution of J0746 shows two continuum components, and is well modeled assuming that the high-energy spectral component results from Comptonization of the broad-line region photons. In this paper, we search for the bulk Compton spectral features predicted to be produced in the soft X-ray band by scattering external optical/UV photons by cold electrons in a relativistic jet. We discuss and provide constraints on the pair content resulting from the apparent absence of such features.

DOI
Fermi Observations of High-Energy Gamma-Ray Emission from GRB 080916C

A. A. Abdo, M. Ackermann, M. Arimoto, K. Asano, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, D. L. Band, G. Barbiellini, M. G. Baring, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, F. Bellardi, R. Bellazzini, B. Berenji, P. N. Bhat, E. Bissaldi, R. D. Blandford, E. D. Bloom, G. Bogaert, J. R. Bogart, E. Bonamente, J. Bonnell, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. S. Briggs, M. Brigida, P. Bruel, T. H. Burnett, D. Burrows, G. Busetto, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, M. Ceccanti, C. Cecchi, A. Celotti, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, V. Connaughton, J. Conrad, L. Costamante, S. Cutini, M. DeKlotz, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, B. L. Dingus, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, P. A. Evans, D. Fabiani, C. Farnier, C. Favuzzi, J. Finke, G. Fishman, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, T. Glanzman, G. Godfrey, A. Goldstein, J. Granot, J. Greiner, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, G. Haller, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, J. A. Hernando Morata, A. Hoover, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, A. Kavelaars, N. Kawai, H. Kelly, J. Kennea, M. Kerr, R. M. Kippen, J. Knoedlseder, D. Kocevski, M. L. Kocian, N. Komin, C. Kouveliotou, F. Kuehn, M. Kuss, J. Lande, D. Landriu, S. Larsson, L. Latronico, C. Lavalley, B. Lee, S. -H. Lee, M. Lemoine-Goumard, G. G. Lichti, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, B. Marangelli, M. N. Mazziotta, S. McBreen, J. E. McEnery, S. McGlynn, C. Meegan, P. Meszaros, C. Meurer, P. F. Michelson, M. Minuti, N. Mirizzi, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, D. Nelson, P. L. Nolan, J. P. Norris, E. Nuss, M. Ohno, T. Ohsugi, A. Okumura, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, W. S. Paciesas, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Perri, M. Pesce-Rollins, V. Petrosian, M. Pinchera, F. Piron, T. A. Porter, R. Preece, S. Raino, E. Ramirez-Ruiz, R. Rando, E. Rapposelli, M. Razzano, S. Razzaque, N. Rea, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, M. Roth, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, K. N. Segal, C. Sgro, T. Shimokawabe, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, M. Stamatikos, J. -L. Starck, F. W. Stecker, H. Steinle, T. E. Stephens, M. S. Strickman, D. J. Suson, G. Tagliaferri, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, A. Tenze, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, M. Turri, S. Tuvi, T. L. Usher, A. J. van der Horst, L. Vigiani, N. Vilchez, V. Vitale, A. von Kienlin, A. P. Waite, D. A. Williams, C. Wilson-Hodge, B. L. Winer, K. S. Wood, X. F. Wu, R. Yamazaki, T. Ylinen, M. Ziegler

SCIENCE 323 ( 5922 ) 1688 - 1693 2009年03月

　概要を見る

Gamma-ray bursts (GRBs) are highly energetic explosions signaling the death of massive stars in distant galaxies. The Gamma-ray Burst Monitor and Large Area Telescope onboard the Fermi Observatory together record GRBs over a broad energy range spanning about 7 decades of gamma-ray energy. In September 2008, Fermi observed the exceptionally luminous GRB 080916C, with the largest apparent energy release yet measured. The high-energy gamma rays are observed to start later and persist longer than the lower energy photons. A simple spectral form fits the entire GRB spectrum, providing strong constraints on emission models. The known distance of the burst enables placing lower limits on the bulk Lorentz factor of the outflow and on the quantum gravity mass.

DOI PubMed CiNii
SUZAKU OBSERVATIONS OF THE EXTREME MeV BLAZAR SWIFT J0746.3+2548

Shin Watanabe, Rie Sato, Tadayuki Takahashi, Jun Kataoka, Greg Madejski, Marek Sikora, Fabrizio Tavecchio, Rita Sambruna, Roger Romani, Philip G. Edwards, Tapio Pursimo

ASTROPHYSICAL JOURNAL 694 ( 1 ) 294 - 301 2009年03月

　概要を見る

We report the Suzaku observations of the high luminosity blazar SWIFT J0746.3+2548 (J0746) conducted in 2005 November. This object, which, with z = 2.979, is the highest redshift source observed in the Suzaku Guaranteed Time Observer period, is likely to show high gamma-ray flux peaking in the MeV range. As a result of the good photon statistics and high signal-to-noise ratio spectrum, the Suzaku observation clearly confirms that J0746 has an extremely hard spectrum in the energy range of 0.3-24 keV, which is well represented by a single power-law with a photon index of Gamma(ph) similar or equal to 1.17 and Galactic absorption. The multiwavelength spectral energy distribution of J0746 shows two continuum components, and is well modeled assuming that the high-energy spectral component results from Comptonization of the broad-line region photons. In this paper, we search for the bulk Compton spectral features predicted to be produced in the soft X-ray band by scattering external optical/UV photons by cold electrons in a relativistic jet. We discuss and provide constraints on the pair content resulting from the apparent absence of such features.

DOI
Fermi Observations of High-Energy Gamma-Ray Emission from GRB 080916C

A. A. Abdo, M. Ackermann, M. Arimoto, K. Asano, W. B. Atwood, M. Axelsson, L. Baldini, J. Ballet, D. L. Band, G. Barbiellini, M. G. Baring, D. Bastieri, M. Battelino, B. M. Baughman, K. Bechtol, F. Bellardi, R. Bellazzini, B. Berenji, P. N. Bhat, E. Bissaldi, R. D. Blandford, E. D. Bloom, G. Bogaert, J. R. Bogart, E. Bonamente, J. Bonnell, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. S. Briggs, M. Brigida, P. Bruel, T. H. Burnett, D. Burrows, G. Busetto, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, J. M. Casandjian, M. Ceccanti, C. Cecchi, A. Celotti, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. R. Cominsky, V. Connaughton, J. Conrad, L. Costamante, S. Cutini, M. DeKlotz, C. D. Dermer, A. de Angelis, F. de Palma, S. W. Digel, B. L. Dingus, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, P. A. Evans, D. Fabiani, C. Farnier, C. Favuzzi, J. Finke, G. Fishman, W. B. Focke, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, T. Glanzman, G. Godfrey, A. Goldstein, J. Granot, J. Greiner, I. A. Grenier, M. -H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, G. Haller, Y. Hanabata, A. K. Harding, M. Hayashida, E. Hays, J. A. Hernando Morata, A. Hoover, R. E. Hughes, G. Johannesson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, A. Kavelaars, N. Kawai, H. Kelly, J. Kennea, M. Kerr, R. M. Kippen, J. Knoedlseder, D. Kocevski, M. L. Kocian, N. Komin, C. Kouveliotou, F. Kuehn, M. Kuss, J. Lande, D. Landriu, S. Larsson, L. Latronico, C. Lavalley, B. Lee, S. -H. Lee, M. Lemoine-Goumard, G. G. Lichti, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, B. Marangelli, M. N. Mazziotta, S. McBreen, J. E. McEnery, S. McGlynn, C. Meegan, P. Meszaros, C. Meurer, P. F. Michelson, M. Minuti, N. Mirizzi, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, D. Nelson, P. L. Nolan, J. P. Norris, E. Nuss, M. Ohno, T. Ohsugi, A. Okumura, N. Omodei, E. Orlando, J. F. Ormes, M. Ozaki, W. S. Paciesas, D. Paneque, J. H. Panetta, D. Parent, V. Pelassa, M. Pepe, M. Perri, M. Pesce-Rollins, V. Petrosian, M. Pinchera, F. Piron, T. A. Porter, R. Preece, S. Raino, E. Ramirez-Ruiz, R. Rando, E. Rapposelli, M. Razzano, S. Razzaque, N. Rea, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, M. Roth, F. Ryde, H. F. -W. Sadrozinski, D. Sanchez, A. Sander, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, K. N. Segal, C. Sgro, T. Shimokawabe, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, M. Stamatikos, J. -L. Starck, F. W. Stecker, H. Steinle, T. E. Stephens, M. S. Strickman, D. J. Suson, G. Tagliaferri, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, A. Tenze, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, M. Turri, S. Tuvi, T. L. Usher, A. J. van der Horst, L. Vigiani, N. Vilchez, V. Vitale, A. von Kienlin, A. P. Waite, D. A. Williams, C. Wilson-Hodge, B. L. Winer, K. S. Wood, X. F. Wu, R. Yamazaki, T. Ylinen, M. Ziegler

SCIENCE 323 ( 5922 ) 1688 - 1693 2009年03月

　概要を見る

Gamma-ray bursts (GRBs) are highly energetic explosions signaling the death of massive stars in distant galaxies. The Gamma-ray Burst Monitor and Large Area Telescope onboard the Fermi Observatory together record GRBs over a broad energy range spanning about 7 decades of gamma-ray energy. In September 2008, Fermi observed the exceptionally luminous GRB 080916C, with the largest apparent energy release yet measured. The high-energy gamma rays are observed to start later and persist longer than the lower energy photons. A simple spectral form fits the entire GRB spectrum, providing strong constraints on emission models. The known distance of the burst enables placing lower limits on the bulk Lorentz factor of the outflow and on the quantum gravity mass.

DOI PubMed CiNii
次期X線天文衛星ASTRO‐H(ex‐NeXT)搭載硬X線イメージャ(HXI)の開発の現状(III)

中澤知洋, 牧島一夫, 国分紀秀, 渡辺伸, 高橋忠幸, 深沢泰司, 片岡淳, 寺田幸功, 山岡和貴, 玉川徹, 田島宏康

日本天文学会年会講演予稿集 2009 260 2009年02月

J-GLOBAL
フェルミ・ガンマ線宇宙望遠鏡によるPWN候補の銀河系内TeVガンマ線源の観測

中森健之, 金井義和, 下川辺隆史, 有元誠, 片岡淳, 河合誠之, 高橋弘充, 山崎了, 片桐秀明, 水野恒史, 深沢泰司, 大杉節, 大野雅功, 佐藤理江, 尾崎正伸, 高橋忠幸, 田中孝明, 林田将明, 内山泰伸, 田島宏康, 釜江常好, FUNK S., GRONDIN M., LEMOINE-GOUMARD M., MAZZIOTTA N.

日本天文学会年会講演予稿集 2009 2009年

J-GLOBAL
Fermiガンマ線宇宙望遠鏡によって検出されたパルサー

河合誠之, 金井義和, 片岡淳, 下川辺隆史, 中森健之, 大杉節, 深沢泰司, 水野恒史, 高橋弘充, 片桐秀明, 高橋忠幸, 尾崎正伸, 田島宏康, 釜江常好, REIMER O., ROMANI R., ATWOOD W., ZIEGLER M., PARKINSON P., WOOD K., ABDO A., HARDING A., THOMPSON D., CHEUNG T., JOHNSON T., CALIANDRO A., RAZZANO M., SMITH D., GUILLEMOT L., KERR M., KANBACH G., TIBOLLA O., BALLET J., GRENIER I.

日本天文学会年会講演予稿集 2009 2009年

J-GLOBAL
MITSuME望遠鏡によるブレーザーの長期モニター観測

森由希, 片岡淳, 河合誠之, 下川辺隆史, 工藤佑允, 中嶋英也, 佐藤理江, 高橋忠幸, MADEJSKI G.

日本天文学会年会講演予稿集 2009 2009年

J-GLOBAL
Fermi衛星で探る高赤方偏移GeVガンマ線ブレーザー天体:宇宙再電離,UV背景放射の解明に向けて

井上芳幸, 井上進, 小林正和, 戸谷友則, 片岡淳, 佐藤理江

日本天文学会年会講演予稿集 2009 2009年

J-GLOBAL
PoGOLite: A balloon-borne soft gamma-ray polarimeter

M. Jackson, M. Pearce, H. Takahashi, M. Axelsson, H.-G. Florén, Y. Fukazawa, S. Gunji, T. Kamae, Y. Kanai, J. Kataoka, N. Kawai, M. Kiss, W. Klamra, S. Larsson, G. Madejski, K. Maeda, P. Mallol, C. Marini Bettolo, Y. Miyamoto, T. Mizuno, G. Olofsson, F. Ryde, S. Rydström, J.-E. Strömberg, H. Tajima, T. Takahashi, T. Tanaka, T. Thurston, G. Varner, H. Yoshida, M. Pearce

IEEE Nuclear Science Symposium Conference Record 2 ( OG PART 1 ) 449 - 453 2009年 [査読有り]

　概要を見る

PoGOLite is a balloon-borne X-ray polarimeter, designed to measure the polarization of 25-80 keV X-rays. It is scheduled for a pathfinder flight in August 2010. This paper outlines the scientific motivation and the status of preparations of the payload. ©2009 IEEE.

DOI
SELENE2ローバー搭載用中性子・ガンマ線分光計

長谷部信行, 鳥居祥二, 片岡淳, 唐牛譲, 山下直之, 武田侑子, 森田幹雄, 小林進悟, 晴山慎, 三谷烈史, 高島健, 小林正規, 荒井朋子, D’USTON Claude, KIM Kyeong Ja, BRUECKNER Johannes

宇宙科学技術連合講演会講演集(CD-ROM) 53rd 1J02 2009年

J-GLOBAL
SELENE2ローバ搭載用ガンマ線・中性子分光計

森田幹雄, 長谷部信行, 鳥居祥二, 片岡淳, 唐牛譲, 早津佳那子, 武田侑子, 長岡央, 三谷烈史, 小林進悟, 晴山慎, 飯島祐一, 高島健, 小林正規, 荒井朋子, D’USTON C, GASNAULT O, 山下直之, KIM K. J, DOHM J. M

太陽系科学シンポジウム講演集録(CD-ROM) 31st ROMBUNNO.12GATSU21NICHI,14 2009年

J-GLOBAL
Suzaku observation of TeV blazar the 1ES 1218+304: clues on particle acceleration in an extreme TeV blazar

R. Sato, J. Kataoka, T. Takahashi, G. M. Medejski, S. Ruegamer, S. J. Wagner

HIGH ENERGY GAMMA-RAY ASTRONOMY 1085 447 - + 2009年

　概要を見る

We observed the TeV blazar 1ES 1218+304 with the X-ray astronomy satellite Suzaku in May 2006. At the beginning of the two-day continuous observation, we detected a large flare in which the 5-10 keV flux changed by a factor of similar to 2 on a timescale of 5 x 10(4) s. During the flare, the increase in the hard X-ray flux clearly lagged behind that observed in the soft X-rays, with the maximum lag of 2.3X10(4) s observed between the 0.3-1 keV and 5-10 keV bands, Furthermore we discovered that the temporal profile of the flare clearly changes with energy, being more symmetric at higher energies. From the spectral fitting of multi-wavelength data assuming a one-zone, homogeneous synchrotron self-Compton model, we obtain a magnetic field strength B similar to 0.047 G, an emission region size R = 3.0 x 10(16) cm for an appropriate beaming with a Doppler factor of delta = 20. This value of B is in good agreement with an independent estimate through the model fit to the observed time lag ascribing the energy-dependent variability to differential acceleration timescale of relativistic electrons provided that the gyro-factor xi is 10(5).

DOI
Suzaku Observations of Tycho's Supernova Remnant

Toru Tamagawa, Asami Hayato, Satoshi Nakamura, Yukikatsu Terada, Aya Bamba, Junko S. Hiraga, John P. Hughes, Una Hwang, Jun Kataoka, Kenzo Kinugasa, Hideyo Kunieda, Takaaki Tanaka, Hiroshi Tsunemi, Masaru Ueno, Stephen S. Holt, Motohide Kokubun, Emi Miyata, Andrew Szymkowiak, Tadayuki Takahashi, Keisuke Tamura, Daisuke Ueno, Kazuo Makishima

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 61 S167 - S174 2009年01月

　概要を見る

Tycho's supernova remnant was observed by the XIS and HXD instruments onboard the Suzaku satellite on 2006 June 26-29 for 92 ks. The spectrum up to 30 keV was well fitted with a two-component model, consisting of a power-law with a photon index of 2.7 and a thermal bremsstrahlung model with a temperature of 4.7 keV. The former component can alternatively be modeled as synchrotron emission from a population of relativistic electrons with an estimated roll-off energy of around 1 keV. In the XIS spectra, in addition to the prominent Fe K alpha line (6.445 keV), we observed for the first time significant K alpha line emission from trace species Cr and Mn at energies of 5.48 keV and 5.95 keV, respectively. Faint K beta lines from Ca (4.56 keV) and Fe (7.11 keV) were also seen. The ionization states of Cr and Mn, based on their line centroids, Lire estimated to be similar to that of Fe K alpha (Fe XV or XVI).

DOI
Suzaku observation of TeV blazar the 1ES 1218+304: clues on particle acceleration in an extreme TeV blazar

R. Sato, J. Kataoka, T. Takahashi, G. M. Medejski, S. Ruegamer, S. J. Wagner

HIGH ENERGY GAMMA-RAY ASTRONOMY 1085 447 - + 2009年

　概要を見る

We observed the TeV blazar 1ES 1218+304 with the X-ray astronomy satellite Suzaku in May 2006. At the beginning of the two-day continuous observation, we detected a large flare in which the 5-10 keV flux changed by a factor of similar to 2 on a timescale of 5 x 10(4) s. During the flare, the increase in the hard X-ray flux clearly lagged behind that observed in the soft X-rays, with the maximum lag of 2.3X10(4) s observed between the 0.3-1 keV and 5-10 keV bands, Furthermore we discovered that the temporal profile of the flare clearly changes with energy, being more symmetric at higher energies. From the spectral fitting of multi-wavelength data assuming a one-zone, homogeneous synchrotron self-Compton model, we obtain a magnetic field strength B similar to 0.047 G, an emission region size R = 3.0 x 10(16) cm for an appropriate beaming with a Doppler factor of delta = 20. This value of B is in good agreement with an independent estimate through the model fit to the observed time lag ascribing the energy-dependent variability to differential acceleration timescale of relativistic electrons provided that the gyro-factor xi is 10(5).

DOI
Suzaku Observations of Tycho's Supernova Remnant

Toru Tamagawa, Asami Hayato, Satoshi Nakamura, Yukikatsu Terada, Aya Bamba, Junko S. Hiraga, John P. Hughes, Una Hwang, Jun Kataoka, Kenzo Kinugasa, Hideyo Kunieda, Takaaki Tanaka, Hiroshi Tsunemi, Masaru Ueno, Stephen S. Holt, Motohide Kokubun, Emi Miyata, Andrew Szymkowiak, Tadayuki Takahashi, Keisuke Tamura, Daisuke Ueno, Kazuo Makishima

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 61 S167 - S174 2009年01月

　概要を見る

Tycho's supernova remnant was observed by the XIS and HXD instruments onboard the Suzaku satellite on 2006 June 26-29 for 92 ks. The spectrum up to 30 keV was well fitted with a two-component model, consisting of a power-law with a photon index of 2.7 and a thermal bremsstrahlung model with a temperature of 4.7 keV. The former component can alternatively be modeled as synchrotron emission from a population of relativistic electrons with an estimated roll-off energy of around 1 keV. In the XIS spectra, in addition to the prominent Fe K alpha line (6.445 keV), we observed for the first time significant K alpha line emission from trace species Cr and Mn at energies of 5.48 keV and 5.95 keV, respectively. Faint K beta lines from Ca (4.56 keV) and Fe (7.11 keV) were also seen. The ionization states of Cr and Mn, based on their line centroids, Lire estimated to be similar to that of Fe K alpha (Fe XV or XVI).

DOI
Chandra reveals twin X-ray jets in the powerful FR II radio galaxy 3C 353

J. Kataoka, L. Stawarz, D. E. Harris, A. Siemiginowska, M. Ostrowski, M. R. Swain, M. J. Hardcastle, J. L. Goodger, K. Iwasawa, P. G. Edwards

ASTROPHYSICAL JOURNAL 685 ( 2 ) 839 - 857 2008年10月

　概要を見る

We report X-ray imaging of the powerful FR II radio galaxy 3C 353 using the Chandra X-Ray Observatory. Due to 3C 353's two 4 '' wide and 2' long jets we are able to study in detail the internal structure of the large-scale relativistic outflows at both radio and X-ray photon energies with the subarcsecond spatial resolution provided by the VLA and Chandra instruments. In a 90 ks Chandra observation, we have detected X-ray emission from most radio structures in 3C 353, including the nucleus, the jet and the counterjet, the terminal jet regions (hot spots), and one radio lobe. We show that the detection of the X-ray emission associated with the radio knots and counterknots, which is most likely nonthermal in origin, puts several crucial constraints on the X-ray emission mechanisms in powerful large-scale jets of quasars and FR II sources. In particular, we show that this detection is inconsistent with the inverse-Compton model proposed in the literature and instead implies a synchrotron origin of the X-ray jet photons. We also find that the width of the X-ray counterjet is possibly narrower than that measured in radio bands, that the radio to X-ray flux ratio decreases systematically downstream along the jets, and that there are substantial (kpc-scale) offsets between the positions of the X-ray and radio intensity maxima within each knot, whose magnitudes increase away from the nucleus. We discuss all these findings in the wider context of the physics of extragalactic jets, proposing some particular although not definitive solutions or interpretations for each problem. In general, we find that the synchrotron X-ray emission of extragalactic large-scale jets is not only shaped by the global hydrodynamical configuration of the outflows, but is also likely to be very sensitive to the microscopic parameters of the jet plasma. A complete, self-consistent model for the X-ray emission of extragalactic jets still remains elusive.

DOI
Chandra reveals twin X-ray jets in the powerful FR II radio galaxy 3C 353

J. Kataoka, L. Stawarz, D. E. Harris, A. Siemiginowska, M. Ostrowski, M. R. Swain, M. J. Hardcastle, J. L. Goodger, K. Iwasawa, P. G. Edwards

ASTROPHYSICAL JOURNAL 685 ( 2 ) 839 - 857 2008年10月

　概要を見る

We report X-ray imaging of the powerful FR II radio galaxy 3C 353 using the Chandra X-Ray Observatory. Due to 3C 353's two 4 '' wide and 2' long jets we are able to study in detail the internal structure of the large-scale relativistic outflows at both radio and X-ray photon energies with the subarcsecond spatial resolution provided by the VLA and Chandra instruments. In a 90 ks Chandra observation, we have detected X-ray emission from most radio structures in 3C 353, including the nucleus, the jet and the counterjet, the terminal jet regions (hot spots), and one radio lobe. We show that the detection of the X-ray emission associated with the radio knots and counterknots, which is most likely nonthermal in origin, puts several crucial constraints on the X-ray emission mechanisms in powerful large-scale jets of quasars and FR II sources. In particular, we show that this detection is inconsistent with the inverse-Compton model proposed in the literature and instead implies a synchrotron origin of the X-ray jet photons. We also find that the width of the X-ray counterjet is possibly narrower than that measured in radio bands, that the radio to X-ray flux ratio decreases systematically downstream along the jets, and that there are substantial (kpc-scale) offsets between the positions of the X-ray and radio intensity maxima within each knot, whose magnitudes increase away from the nucleus. We discuss all these findings in the wider context of the physics of extragalactic jets, proposing some particular although not definitive solutions or interpretations for each problem. In general, we find that the synchrotron X-ray emission of extragalactic large-scale jets is not only shaped by the global hydrodynamical configuration of the outflows, but is also likely to be very sensitive to the microscopic parameters of the jet plasma. A complete, self-consistent model for the X-ray emission of extragalactic jets still remains elusive.

DOI
Study of nonthermal emission from SNR RX J1713.7-3946 with Suzaku

Takaaki Tanaka, Yasunobu Uchiyama, Felix A. Aharonian, Tadayuki Takahashi, Aya Bamba, Junko S. Hiraga, Jun Kataoka, Tetsuichi Kishishita, Motohide Kokubun, Koji Mori, Kazuhiro Nakazawa, Robert Petre, Hiroyasu Tajima, Shin Watanabe

ASTROPHYSICAL JOURNAL 685 ( 2 ) 988 - 1004 2008年10月

　概要を見る

We present results obtained from a series of observations of the supernova remnant RX J1713.7-3946 by Suzaku. Hard X-rays have been detected up to similar to 40 keV. The hard X-ray spectra are described by a power law with photon indices of similar to 3.0, which is larger than those below 10 keV. The combination of the spatially integrated XIS and HXD spectra clearly reveals a spectral cutoff which is linked to the maximum energy of accelerated electrons. The broad-band coverage of Suzaku allows us to derive, for the first time, the energy spectrum of parent electrons in the cutoff region. The cutoff energy in the X-ray spectrum indicates that the electron acceleration in the remnant proceeds close to the Bohm diffusion limit. We discuss the implications of the spectral and morphological properties of the Suzaku data in the context of the origin of nonthermal emission. The Suzaku X-ray and H.E.S.S. gamma-ray data together hardly can be explained within a pure leptonic scenario. Moreover, the leptonic models require a weak magnetic field, which is inconsistent with the recently discovered X-ray filamentary structures and their short-term variability. The hadronic models with strong magnetic fields provide reasonable fits to the observed spectra, but require special arrangements of parameters to explain the lack of thermal X-ray emission. For morphology studies, we compare the X-ray and TeV gamma-ray surface brightness. We confirm the previously reported strong correlation between X-rays and TeV gamma rays. At the same time, the Suzaku data reveal a deviation from the general tendency, namely, the X-ray emission in the western rims appears brighter than expected from the average X-ray to gamma-ray ratio.

DOI
Chandra reveals twin X-ray jets in the powerful FR II radio galaxy 3C 353

J. Kataoka, L. Stawarz, D. E. Harris, A. Siemiginowska, M. Ostrowski, M. R. Swain, M. J. Hardcastle, J. L. Goodger, K. Iwasawa, P. G. Edwards

ASTROPHYSICAL JOURNAL 685 ( 2 ) 839 - 857 2008年10月

　概要を見る

We report X-ray imaging of the powerful FR II radio galaxy 3C 353 using the Chandra X-Ray Observatory. Due to 3C 353's two 4 '' wide and 2' long jets we are able to study in detail the internal structure of the large-scale relativistic outflows at both radio and X-ray photon energies with the subarcsecond spatial resolution provided by the VLA and Chandra instruments. In a 90 ks Chandra observation, we have detected X-ray emission from most radio structures in 3C 353, including the nucleus, the jet and the counterjet, the terminal jet regions (hot spots), and one radio lobe. We show that the detection of the X-ray emission associated with the radio knots and counterknots, which is most likely nonthermal in origin, puts several crucial constraints on the X-ray emission mechanisms in powerful large-scale jets of quasars and FR II sources. In particular, we show that this detection is inconsistent with the inverse-Compton model proposed in the literature and instead implies a synchrotron origin of the X-ray jet photons. We also find that the width of the X-ray counterjet is possibly narrower than that measured in radio bands, that the radio to X-ray flux ratio decreases systematically downstream along the jets, and that there are substantial (kpc-scale) offsets between the positions of the X-ray and radio intensity maxima within each knot, whose magnitudes increase away from the nucleus. We discuss all these findings in the wider context of the physics of extragalactic jets, proposing some particular although not definitive solutions or interpretations for each problem. In general, we find that the synchrotron X-ray emission of extragalactic large-scale jets is not only shaped by the global hydrodynamical configuration of the outflows, but is also likely to be very sensitive to the microscopic parameters of the jet plasma. A complete, self-consistent model for the X-ray emission of extragalactic jets still remains elusive.

DOI
Study of nonthermal emission from SNR RX J1713.7-3946 with Suzaku

Takaaki Tanaka, Yasunobu Uchiyama, Felix A. Aharonian, Tadayuki Takahashi, Aya Bamba, Junko S. Hiraga, Jun Kataoka, Tetsuichi Kishishita, Motohide Kokubun, Koji Mori, Kazuhiro Nakazawa, Robert Petre, Hiroyasu Tajima, Shin Watanabe

ASTROPHYSICAL JOURNAL 685 ( 2 ) 988 - 1004 2008年10月

　概要を見る

We present results obtained from a series of observations of the supernova remnant RX J1713.7-3946 by Suzaku. Hard X-rays have been detected up to similar to 40 keV. The hard X-ray spectra are described by a power law with photon indices of similar to 3.0, which is larger than those below 10 keV. The combination of the spatially integrated XIS and HXD spectra clearly reveals a spectral cutoff which is linked to the maximum energy of accelerated electrons. The broad-band coverage of Suzaku allows us to derive, for the first time, the energy spectrum of parent electrons in the cutoff region. The cutoff energy in the X-ray spectrum indicates that the electron acceleration in the remnant proceeds close to the Bohm diffusion limit. We discuss the implications of the spectral and morphological properties of the Suzaku data in the context of the origin of nonthermal emission. The Suzaku X-ray and H.E.S.S. gamma-ray data together hardly can be explained within a pure leptonic scenario. Moreover, the leptonic models require a weak magnetic field, which is inconsistent with the recently discovered X-ray filamentary structures and their short-term variability. The hadronic models with strong magnetic fields provide reasonable fits to the observed spectra, but require special arrangements of parameters to explain the lack of thermal X-ray emission. For morphology studies, we compare the X-ray and TeV gamma-ray surface brightness. We confirm the previously reported strong correlation between X-rays and TeV gamma rays. At the same time, the Suzaku data reveal a deviation from the general tendency, namely, the X-ray emission in the western rims appears brighter than expected from the average X-ray to gamma-ray ratio.

DOI
Chandra reveals twin X-ray jets in the powerful FR II radio galaxy 3C 353

J. Kataoka, L. Stawarz, D. E. Harris, A. Siemiginowska, M. Ostrowski, M. R. Swain, M. J. Hardcastle, J. L. Goodger, K. Iwasawa, P. G. Edwards

ASTROPHYSICAL JOURNAL 685 ( 2 ) 839 - 857 2008年10月

　概要を見る

We report X-ray imaging of the powerful FR II radio galaxy 3C 353 using the Chandra X-Ray Observatory. Due to 3C 353's two 4 '' wide and 2' long jets we are able to study in detail the internal structure of the large-scale relativistic outflows at both radio and X-ray photon energies with the subarcsecond spatial resolution provided by the VLA and Chandra instruments. In a 90 ks Chandra observation, we have detected X-ray emission from most radio structures in 3C 353, including the nucleus, the jet and the counterjet, the terminal jet regions (hot spots), and one radio lobe. We show that the detection of the X-ray emission associated with the radio knots and counterknots, which is most likely nonthermal in origin, puts several crucial constraints on the X-ray emission mechanisms in powerful large-scale jets of quasars and FR II sources. In particular, we show that this detection is inconsistent with the inverse-Compton model proposed in the literature and instead implies a synchrotron origin of the X-ray jet photons. We also find that the width of the X-ray counterjet is possibly narrower than that measured in radio bands, that the radio to X-ray flux ratio decreases systematically downstream along the jets, and that there are substantial (kpc-scale) offsets between the positions of the X-ray and radio intensity maxima within each knot, whose magnitudes increase away from the nucleus. We discuss all these findings in the wider context of the physics of extragalactic jets, proposing some particular although not definitive solutions or interpretations for each problem. In general, we find that the synchrotron X-ray emission of extragalactic large-scale jets is not only shaped by the global hydrodynamical configuration of the outflows, but is also likely to be very sensitive to the microscopic parameters of the jet plasma. A complete, self-consistent model for the X-ray emission of extragalactic jets still remains elusive.

DOI
PoGOLite – A High Sensitivity Balloon-Borne Soft Gamma-ray Polarimeter

Kamae et a

Astroparticle Physics 30 ( 2 ) 72 - 84 2008年09月

DOI
PoGOLite - A high sensitivity balloon-borne soft gamma-ray polarimeter

Tuneyoshi Kamae, Viktor Andersson, Makoto Arimoto, Magnus Axelsson, Cecilia Marini Bettolo, Claes-Ingvar Bjornsson, Gilles Bogaert, Per Carlson, William Craig, Tomas Ekeberg, Olle Engdegdrd, Yasushi Fukazawa, Shuichi Gunji, Linnea Hjalmarsdotter, Bianca Iwan, Yoshikazu Kanai, Jun Kataoka, Nobuyuki Kawai, Jaroslav Kazejev, Mozsi Kiss, Wlodzimierz Klamra, Stefan Larsson, Grzegorz Madejski, Tsunefumi Mizuno, Johnny Ng, Mark Pearce, Felix Ryde, Markus Suhonen, Hiroyasu TaJima, Hiromitsu Takahashi, Tadayuki Takahashi, Takuya Tanaka, Timothy Thurston, Masaru Ueno, Gary Varneri, Kazuhide Yamamoto, Yuichiro Yamashita, Tomi Ylinen, Hiroaki Yoshida

ASTROPARTICLE PHYSICS 30 ( 2 ) 72 - 84 2008年09月

　概要を見る

We describe a new balloon-borne instrument (PoGOLite) capable of detecting 10% polarisation from 200 mCrab point-like sources between 25 and 80 keV in one 6-h flight. Polarisation measurements in the soft gamma-ray band are expected to provide a powerful probe into high energy emission mechanisms as well as the distribution of magnetic fields, radiation fields and interstellar matter. Synchrotron radiation, inverse Compton scattering and propagation through high magnetic fields are likely to produce high degrees of polarisation in the energy band of the instrument. We demonstrate, through tests at accelerators, with radioactive sources and through computer simulations, that PoGOLite will be able to detect degrees of polarisation as predicted by models for several classes of high energy sources. At present, only exploratory polarisation measurements have been carried out in the soft gamma-ray band. Reduction of the large background produced by cosmic-ray particles while securing a large effective area has been the greatest challenge. PoGOLite uses Compton scattering and photo-absorption in an array of 217 well-type phoswich detector cells made of plastic and BGO scintillators surrounded by a BGO anticoincidence shield and a thick polyethylene neutron shield. The narrow Held of view (FWHM = 1.25 msr, 2.0 deg x 2.0 deg) obtained with detector cells and the use of thick background shields warrant a large effective area for polarisation measurements (similar to 228 cm(2) at E = 40 keV) without sacrificing the signal-to-noise ratio. Simulation studies for an atmospheric overburden of 3-4 g/cm(2) indicate that neutrons and gamma-rays entering the PDC assembly through the shields are dominant backgrounds. Off-line event selection based on recorded phototube waveforms and Compton kinematics reduce the background to that expected for a similar to 100 mCrab source between 25 and 50 keV. A 6-h observation of the Crab pulsar will differentiate between the Polar Cap/Slot Gap, Outer Gap, and Caustic models with greater than 5 sigma significance; and also cleanly identify the Compton reflection component in the Cygnus X-1 hard state. Long-duration flights will measure the dependence of the polarisation across the cyclotron absorption line in Hercules X-1. A scaled-down instrument will be flown as a pathfinder mission from the north of Sweden in 2010. The first science flight is planned to take place shortly thereafter. (C) 2008 Elsevier B.V. All rights reserved.

DOI
APDによるNeXT衛星軟γ線検出器BGOアクティブシールドの光読み出し

池尻祐輝, 深沢泰司, 深水浩司, 片岡淳, 戸泉貴裕, 和田健介, 中澤知洋, 国分紀秀, 高橋忠幸, 田島宏康, 森国城

日本天文学会年会講演予稿集 2008 263 2008年08月

J-GLOBAL
Evolution of and high-energy emission from GHz-peaked spectrum sources

L. Stawarz, L. Ostorero, M. C. Begelman, R. Moderski, J. Kataoka, S. Wagner

ASTROPHYSICAL JOURNAL 680 ( 2 ) 911 - 925 2008年06月

書評論文，書評，文献紹介等

　概要を見る

Here we discuss evolution and broadband emission of compact (< kpc) lobes in young radio sources. We propose a simple dynamical description for these objects, consisting of a relativistic jet propagating into a uniform gaseous medium in the central parts of an elliptical host. In the framework of the proposed model we follow the evolution of ultra-relativistic electrons injected from a terminal hot spot of a jet to expanding lobes, taking into account their adiabatic energy losses, as well as radiative cooling. This allows us to discuss the broadband lobe emission of young radio sources. In particular, we argue that the observed spectral turnover in the radio synchrotron spectra of these objects cannot originate from the synchrotron self-absorption process but is most likely due to free-free absorption effects connected with neutral clouds of interstellar medium engulfed by the expanding lobes and photoionized by active centers. We also find a relatively strong and complex high-energy emission component produced by inverse Compton upscattering of various surrounding photon fields by the lobes' electrons. We argue that such high-energy radiation is strong enough to account for several observed properties of GHz-peaked spectrum (GPS) radio galaxies at UV- and X-ray frequencies. In addition, this emission is expected to extend up to GeV (or possibly even TeV) photon energies and can thus be probed by several modern gamma-ray instruments. In particular, we suggest that GPS radio galaxies should constitute a relatively numerous class of extragalactic sources detected by GLAST.

DOI
Evolution of and high-energy emission from GHz-peaked spectrum sources

L. Stawarz, L. Ostorero, M. C. Begelman, R. Moderski, J. Kataoka, S. Wagner

ASTROPHYSICAL JOURNAL 680 ( 2 ) 911 - 925 2008年06月

書評論文，書評，文献紹介等

　概要を見る

Here we discuss evolution and broadband emission of compact (< kpc) lobes in young radio sources. We propose a simple dynamical description for these objects, consisting of a relativistic jet propagating into a uniform gaseous medium in the central parts of an elliptical host. In the framework of the proposed model we follow the evolution of ultra-relativistic electrons injected from a terminal hot spot of a jet to expanding lobes, taking into account their adiabatic energy losses, as well as radiative cooling. This allows us to discuss the broadband lobe emission of young radio sources. In particular, we argue that the observed spectral turnover in the radio synchrotron spectra of these objects cannot originate from the synchrotron self-absorption process but is most likely due to free-free absorption effects connected with neutral clouds of interstellar medium engulfed by the expanding lobes and photoionized by active centers. We also find a relatively strong and complex high-energy emission component produced by inverse Compton upscattering of various surrounding photon fields by the lobes' electrons. We argue that such high-energy radiation is strong enough to account for several observed properties of GHz-peaked spectrum (GPS) radio galaxies at UV- and X-ray frequencies. In addition, this emission is expected to extend up to GeV (or possibly even TeV) photon energies and can thus be probed by several modern gamma-ray instruments. In particular, we suggest that GPS radio galaxies should constitute a relatively numerous class of extragalactic sources detected by GLAST.

DOI
次期X線天文衛星NeXT搭載硬X線撮像検出器(HXI)の開発(II)

国分紀秀, 渡辺伸, 佐藤理江, 武田伸一郎, 石川真之介, 小高裕和, 青野博之, 高橋忠幸, 深沢泰司, 中澤知洋, 片岡淳, 寺田幸功, 山岡和貴, 玉川徹

日本天文学会年会講演予稿集 2008 247 2008年02月

J-GLOBAL
Measuring the broad-band X-ray spectrum from 400 eV to 40 keV in the southwest part of the supernova remnant RX J1713.7-3946

Tadayuki Takahashi, Takaaki Tanaka, Yasunobu Uchiyama, Junko S. Hiraga, Kazuhiro Nakazawa, Shin Watanabe, Aya Bamba, John P. Hughes, Hideaki Katagiri, Jun Kataoka, Motohide Kokubun, Katsuji Koyama, Koji Mori, Robert Petre, Hiromitsu Takahashi, Yoko Tsuboi

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 60 S131 - S140 2008年02月

　概要を見る

We report on results from Suzaku broadband X-ray observations of the southwest part of the galactic supernova remnant (SNR) RX J1713.7-3946 with an energy coverage of 0.4-40keV. The X-ray spectrum, presumably of synchrotron origin, is known to be completely lineless, making this SNR ideally suited for a detailed study of the X-ray spectral shape formed through efficient particle acceleration at high-speed shocks. With a sensitive hard X-ray measurement from the HXD PIN aboard Suzaku, we determined the hard X-ray spectrum in the 12-40 keV range to be described by a power law with photon index of Gamma = 3.2 +/- 0.2, significantly steeper than the soft X-ray index of Gamma = 2.4 +/- 0.05 measured previously with ASCA and other missions. We find that a simple power law fails to describe the full spectral range of 0.4-40 keV, and instead a power-law with an exponential cutoff with a hard index of Gamma = 1.50 +/- 0.09 and a high-energy cutoff of epsilon(c) = 1.2 +/- 0.3 keV formally provides an excellent fit over the full bandpass. If we use the so-called SRCUT model, as an alternative model, it gives a best-fit rolloff energy of epsilon(roll) = 0.95 +/- 0.04 keV. Together with the TeV gamma-ray spectrum, ranging from 0.3 to 100 TeV, recently obtained by HESS observations, our Suzaku observations of RX J1713.7-3946 provide stringent constraints on the highest-energy particles accelerated in a supernova shock.

DOI
Measuring the broad-band X-ray spectrum from 400 eV to 40 keV in the southwest part of the supernova remnant RX J1713.7-3946

Tadayuki Takahashi, Takaaki Tanaka, Yasunobu Uchiyama, Junko S. Hiraga, Kazuhiro Nakazawa, Shin Watanabe, Aya Bamba, John P. Hughes, Hideaki Katagiri, Jun Kataoka, Motohide Kokubun, Katsuji Koyama, Koji Mori, Robert Petre, Hiromitsu Takahashi, Yoko Tsuboi

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 60 S131 - S140 2008年02月

　概要を見る

We report on results from Suzaku broadband X-ray observations of the southwest part of the galactic supernova remnant (SNR) RX J1713.7-3946 with an energy coverage of 0.4-40keV. The X-ray spectrum, presumably of synchrotron origin, is known to be completely lineless, making this SNR ideally suited for a detailed study of the X-ray spectral shape formed through efficient particle acceleration at high-speed shocks. With a sensitive hard X-ray measurement from the HXD PIN aboard Suzaku, we determined the hard X-ray spectrum in the 12-40 keV range to be described by a power law with photon index of Gamma = 3.2 +/- 0.2, significantly steeper than the soft X-ray index of Gamma = 2.4 +/- 0.05 measured previously with ASCA and other missions. We find that a simple power law fails to describe the full spectral range of 0.4-40 keV, and instead a power-law with an exponential cutoff with a hard index of Gamma = 1.50 +/- 0.09 and a high-energy cutoff of epsilon(c) = 1.2 +/- 0.3 keV formally provides an excellent fit over the full bandpass. If we use the so-called SRCUT model, as an alternative model, it gives a best-fit rolloff energy of epsilon(roll) = 0.95 +/- 0.04 keV. Together with the TeV gamma-ray spectrum, ranging from 0.3 to 100 TeV, recently obtained by HESS observations, our Suzaku observations of RX J1713.7-3946 provide stringent constraints on the highest-energy particles accelerated in a supernova shock.

DOI
ガンマ線バースト硬X線偏光観測衛星「つばめ」の開発現状

戸泉貴裕, 津布久佳宏, 小林光吉, 下川辺隆史, 谷津陽一, 片岡淳, 河合誠之

日本天文学会年会講演予稿集 2008 2008年

J-GLOBAL
ブレーザー3C 454.3の“ガンマ線フレア”多波長同時観測

森由希, 片岡淳, 河合誠之, 石村拓人, 工藤佑允, 下川辺隆史, 谷津陽一, 高橋忠幸, 佐藤理江, TAVANINI M., TOSTI G., MADEJSKI G., GIOMMI P.

日本天文学会年会講演予稿集 2008 2008年

J-GLOBAL
MITSuME望遠鏡の無人自動観測・自動解析システム

下川辺隆史, 河合誠之, 片岡淳, 森由希, 工藤佑允, 中嶋英也, 吉田道利, 柳澤顕史, 長山省吾, 戸田博之, 黒田大介, 清水康広, 渡部潤一, 福島英雄, 森正樹

日本天文学会年会講演予稿集 2008 2008年

J-GLOBAL
23aSH-1 GeVガンマ線観測衛星GLASTの初期ステータス(23aSH X線・γ線,宇宙線・宇宙物理領域)

深沢泰司, 河合誠之, 片岡淳, 中森健之, 金井義和, 下川辺隆史, 高橋忠幸, 尾崎正伸, 大野雅功, 佐藤理江, 釜江常好, 大杉節, 田島宏康, 田中孝明, 奥村暁, 牧島一夫, GLASTチーム, 水野恒史, 片桐秀明, 高橋弘充, 安田創, 西野翔, 吉田広明, 花畑義隆

日本物理学会講演概要集 63 ( 0 ) 2008年

CiNii J-GLOBAL
Multiwavelength observations of the powerful gamma-ray quasar PKS 1510-089: Clues on the jet composition

J. Kataoka, G. Madejski, M. Sikora, P. Roming, M. M. Chester, D. Grupe, Y. Tsubuku, R. Sato, N. Kawai, G. Tosti, D. Impiombato, Y. Y. Kovalev, Y. A. Kovalev, P. G. Edwards, S. J. Wagner, R. Moderski, L. Stawarz, T. Takahashi, S. Watanabe

ASTROPHYSICAL JOURNAL 672 ( 2 ) 787 - 799 2008年01月

　概要を見る

We present the results from a multiwavelength campaign conducted in 2006 August of the powerful gamma-ray quasar PKS 1510-089 (z = 0.361). This campaign commenced with a deep Suzaku observation lasting 3 days for a total exposure time of 120 ks and continued with Swift monitoring over 18 days. Besides Swift observations, the campaign included ground-based optical and radio data and yielded a quasi-simultaneous broadband spectrum from 10(9) to 10(19) Hz. The Suzaku observation provided a high signal-to-noise ratio X-ray spectrum, which is well represented by an extremely hard power law with a photon index of Gamma similar or equal to 1.2, augmented by a soft component apparent below 1 keV, which is well described by a blackbody model with a temperature of kT similar or equal to 0.2 keV. Monitoring by Suzaku revealed temporal variability that differs between the low- and high-energy bands, again suggesting the presence of a second, variable component in addition to the primary power-law emission. We model the broadband spectrum, assuming that the high-energy spectral component results from Comptonization of infrared radiation produced by hot dust located in the surrounding molecular torus. The adopted internal shock scenario implies that the power of the jet is dominated by protons, but with a number of electrons and/or positrons that exceeds the number of protons by a factor of similar to 10. We also find that inhomogeneities responsible for the shock formation prior to the collision may produce bulk Compton radiation, which can explain the observed soft X-ray excess and possible excess at similar to 18 keV. We note, however, that the bulk Compton interpretation is not unique, as discussed briefly in the text.

DOI
Multiwavelength observations of the powerful gamma-ray quasar PKS 1510-089: Clues on the jet composition

J. Kataoka, G. Madejski, M. Sikora, P. Roming, M. M. Chester, D. Grupe, Y. Tsubuku, R. Sato, N. Kawai, G. Tosti, D. Impiombato, Y. Y. Kovalev, Y. A. Kovalev, P. G. Edwards, S. J. Wagner, R. Moderski, L. Stawarz, T. Takahashi, S. Watanabe

ASTROPHYSICAL JOURNAL 672 ( 2 ) 787 - 799 2008年01月

　概要を見る

We present the results from a multiwavelength campaign conducted in 2006 August of the powerful gamma-ray quasar PKS 1510-089 (z = 0.361). This campaign commenced with a deep Suzaku observation lasting 3 days for a total exposure time of 120 ks and continued with Swift monitoring over 18 days. Besides Swift observations, the campaign included ground-based optical and radio data and yielded a quasi-simultaneous broadband spectrum from 10(9) to 10(19) Hz. The Suzaku observation provided a high signal-to-noise ratio X-ray spectrum, which is well represented by an extremely hard power law with a photon index of Gamma similar or equal to 1.2, augmented by a soft component apparent below 1 keV, which is well described by a blackbody model with a temperature of kT similar or equal to 0.2 keV. Monitoring by Suzaku revealed temporal variability that differs between the low- and high-energy bands, again suggesting the presence of a second, variable component in addition to the primary power-law emission. We model the broadband spectrum, assuming that the high-energy spectral component results from Comptonization of infrared radiation produced by hot dust located in the surrounding molecular torus. The adopted internal shock scenario implies that the power of the jet is dominated by protons, but with a number of electrons and/or positrons that exceeds the number of protons by a factor of similar to 10. We also find that inhomogeneities responsible for the shock formation prior to the collision may produce bulk Compton radiation, which can explain the observed soft X-ray excess and possible excess at similar to 18 keV. We note, however, that the bulk Compton interpretation is not unique, as discussed briefly in the text.

DOI
Oxygen line mapping of SN 1006 with Suzaku

Aya Bamba, Hiroya Yamaguchi, KatsuJi Koyama, Junko S. Hiraga, Steve Holt, John P. Hughes, Hideaki Katagiri, Jun Kataoka, Satoru Katsuda, Shunji Kitamoto, Motohide Kokubun, Hironori Matsumoto, Emi Miyata, Koji Mori, Hiroshi Nakajima, Masanobu Ozaki, Rob Petre, Akiko Sekiguchi, Tadayuki Takahashi, Takaaki Tanaka, Yukikatsu Terada, Hiroshi Tomida, Yohko Tsuboi, Masahiro Tsujimoto, Hiroshi Tsunemi, Yasunobu Uchiyama, Masaru Ueno, Shin Watanabe

ADVANCES IN SPACE RESEARCH 41 ( 3 ) 411 - 415 2008年

　概要を見る

SN 1006 is one of the supernova remnants (SNRs) with relatively low-temperature electrons, considering the young age of just 1000 years. We carried out SN 1006 mapping observations with the X-ray Imaging Spectrometers (XIS) and the Hard X-ray Detector (HXD) onboard Suzaku, the fifth Japanese X-ray satellite. Thanks to the excellent spectral resolution of XIS in the soft X-ray band, H-like and He-like oxygen emission lines were clearly detected, and we could make a map of the line intensity, and as well as a flux and the photon index of nonthermal component. We found that these parameters have spatial dependences from region to region in the SNR; the north region is bright in nonthermal, while dim in thermal; the east region is bright in both nonthermal and thermal; the inner region shows dim nonthermal and bright thermal emission. The photon index is the smallest in the north region. (C) 2007 Published by Elsevier Ltd on behalf of COSPAR.

DOI
Environmental tests of the flight GLAST LAT tracker towers

R. Bagagli, L. Baldini, R. Bellazzini, G. Barblellini, F. Belli, T. Borden, A. Brez, M. Brigida, G. A. Caliandro, C. Cecchi, J. Cohen-Tanugi, A. De Angelis, P. Drell, C. Favuzzi, P. Fusco, F. Gargano, S. Germani, N. Giglietto, F. Giordano, J. Goodman, T. Himel, M. Hirayama, R. P. Johnson, H. Katagiri, J. Kataoka, N. Kawai, W. Kroeger, J. Ku, M. Kuss, L. Latronico, F. Longo, F. Loparco, P. Lubrano, B. Marangelli, F. Marcucci, M. Marchetti, M. M. Massai, M. N. Mazziotta, M. Minori, M. Minuti, N. Mirizzi, M. Mongelli, C. Monte, A. Morselli, D. Nelson, M. Nordby, N. Omodei, M. Pepe, M. Pesce-Rollins, S. Raino, R. Rando, M. Razzano, D. Rich, G. Scolieri, C. Sgro, G. Spandre, P. Spinelli, M. Sugizaki, H. Takahashi, A. Tenze, C. Young

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 584 ( 2-3 ) 358 - 373 2008年01月

　概要を見る

The Gamma-ray Large Area Space telescope (GLAST) is a gamma-ray satellite scheduled for launch in 2008. Before the assembly of the Tracker subsystem of the Large Area Telescope (LAT) science instrument of GLAST, every component (tray) and module (tower) has been subjected to extensive ground testing required to ensure successful launch and on-orbit operation. This paper describes the sequence and results of the environmental tests performed on an engineering model and all the flight hardware of the GLAST LAT Tracker. Environmental tests include vibration testing, thermal cycles and thermal-vacuum cycles of every tray and tower as well as the verification of their electrical performance. (C) 2007 Elsevier B.V. All rights reserved.

DOI CiNii
Oxygen line mapping of SN 1006 with Suzaku

Aya Bamba, Hiroya Yamaguchi, KatsuJi Koyama, Junko S. Hiraga, Steve Holt, John P. Hughes, Hideaki Katagiri, Jun Kataoka, Satoru Katsuda, Shunji Kitamoto, Motohide Kokubun, Hironori Matsumoto, Emi Miyata, Koji Mori, Hiroshi Nakajima, Masanobu Ozaki, Rob Petre, Akiko Sekiguchi, Tadayuki Takahashi, Takaaki Tanaka, Yukikatsu Terada, Hiroshi Tomida, Yohko Tsuboi, Masahiro Tsujimoto, Hiroshi Tsunemi, Yasunobu Uchiyama, Masaru Ueno, Shin Watanabe

ADVANCES IN SPACE RESEARCH 41 ( 3 ) 411 - 415 2008年

　概要を見る

SN 1006 is one of the supernova remnants (SNRs) with relatively low-temperature electrons, considering the young age of just 1000 years. We carried out SN 1006 mapping observations with the X-ray Imaging Spectrometers (XIS) and the Hard X-ray Detector (HXD) onboard Suzaku, the fifth Japanese X-ray satellite. Thanks to the excellent spectral resolution of XIS in the soft X-ray band, H-like and He-like oxygen emission lines were clearly detected, and we could make a map of the line intensity, and as well as a flux and the photon index of nonthermal component. We found that these parameters have spatial dependences from region to region in the SNR; the north region is bright in nonthermal, while dim in thermal; the east region is bright in both nonthermal and thermal; the inner region shows dim nonthermal and bright thermal emission. The photon index is the smallest in the north region. (C) 2007 Published by Elsevier Ltd on behalf of COSPAR.

DOI
Environmental tests of the flight GLAST LAT tracker towers

R. Bagagli, L. Baldini, R. Bellazzini, G. Barblellini, F. Belli, T. Borden, A. Brez, M. Brigida, G. A. Caliandro, C. Cecchi, J. Cohen-Tanugi, A. De Angelis, P. Drell, C. Favuzzi, P. Fusco, F. Gargano, S. Germani, N. Giglietto, F. Giordano, J. Goodman, T. Himel, M. Hirayama, R. P. Johnson, H. Katagiri, J. Kataoka, N. Kawai, W. Kroeger, J. Ku, M. Kuss, L. Latronico, F. Longo, F. Loparco, P. Lubrano, B. Marangelli, F. Marcucci, M. Marchetti, M. M. Massai, M. N. Mazziotta, M. Minori, M. Minuti, N. Mirizzi, M. Mongelli, C. Monte, A. Morselli, D. Nelson, M. Nordby, N. Omodei, M. Pepe, M. Pesce-Rollins, S. Raino, R. Rando, M. Razzano, D. Rich, G. Scolieri, C. Sgro, G. Spandre, P. Spinelli, M. Sugizaki, H. Takahashi, A. Tenze, C. Young

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 584 ( 2-3 ) 358 - 373 2008年01月

　概要を見る

The Gamma-ray Large Area Space telescope (GLAST) is a gamma-ray satellite scheduled for launch in 2008. Before the assembly of the Tracker subsystem of the Large Area Telescope (LAT) science instrument of GLAST, every component (tray) and module (tower) has been subjected to extensive ground testing required to ensure successful launch and on-orbit operation. This paper describes the sequence and results of the environmental tests performed on an engineering model and all the flight hardware of the GLAST LAT Tracker. Environmental tests include vibration testing, thermal cycles and thermal-vacuum cycles of every tray and tower as well as the verification of their electrical performance. (C) 2007 Elsevier B.V. All rights reserved.

DOI CiNii
Design and initial tests of the Tracker-converter of the Gamma-ray Large Area Space Telescope

W. B. Atwood, R. Bagagli, L. Baldini, R. Bellazzini, G. Barbiellini, F. Belli, T. Borden, A. Brez, M. Brigida, G. A. Caliandro, C. Cecchi, J. Cohen-Tanugi, A. De Angelis, P. Drell, C. Favuzzi, Y. Fukazawa, P. Fusco, F. Gargano, S. Germani, R. Giannitrapani, N. Giglietto, F. Giordano, T. Himel, M. Hirayama, R. P. Johnson, H. Katagiri, J. Kataoka, N. Kawai, W. Kroeger, M. Kuss, L. Latronico, F. Longo, F. Loparco, P. Lubrano, M. M. Massai, M. N. Mazziotta, M. Minuti, T. Mizuno, A. Morselli, D. Nelson, M. Nordby, T. Ohsugi, N. Omodei, M. Ozaki, M. Pepe, S. Raino, R. Rando, M. Razzano, D. Rich, H. F. -W. Sadrozinski, G. Scolieri, C. Sgro, G. Spandre, P. Spinelli, M. Sugizaki, H. Tajima, H. Takahashi, T. Takahashi, S. Yoshida, C. Young, M. Ziegler

ASTROPARTICLE PHYSICS 28 ( 4-5 ) 422 - 434 2007年12月

　概要を見る

The Tracker subsystem of the Large Area Telescope (LAT) science instrument of the Gamma-ray Large Area Space Telescope (GLAST) mission has been completed and tested. It is the central detector subsystem of the LAT and serves both to convert an incident gamma-ray into an electron-positron pair and to track the pair in order to measure the gamma-ray direction. It also provides the principal trigger for the LAT. The Tracker uses silicon strip detectors, read out by custom electronics, to detect charged particles. The detectors and electronics are packaged, along with tungsten converter foils, in 16 modular, high-precision carbon-composite structures. It is the largest silicon-strip detector system ever built for launch into space, and its aggressive design emphasizes very low power consumption, passive cooling, low noise, high efficiency, minimal dead area, and a structure that is highly transparent to charged particles. The test program has demonstrated that the system meets or surpasses all of its performance specifications as well as environmental requirements. It is now installed in the completed LAT, which is being prepared for launch in early 2008. (c) 2007 Elsevier B.V. All rights reserved.

DOI
Construction, test and calibration of the GLAST silicon tracker

C. Sgro, W. B. Atwood, L. Baldini, G. Barbiellini, R. Bellazzini, F. Belli, E. Bonamente, T. Borden, J. Bregeon, A. Brez, M. Brigida, G. A. Caliandro, C. Cecchi, J. Cohen-Tanugi, A. De Angelis, P. Drell, C. Favuzzi, Y. Fukazawa, P. Fusco, F. Gargano, S. Germani, N. Giglietto, F. Giordano, T. Himel, M. Hirayama, R. P. Johnson, H. Katagiri, J. Kataoka, N. Kawai, W. Kroeger, M. Kuss, L. Latronico, F. Longo, F. Loparco, P. Lubrano, M. M. Massai, M. N. Mazziotta, M. Minuti, T. Mizuno, A. Morselli, D. Nelson, M. Nordby, T. Ohsugi, N. Omodei, M. Ozaki, M. Pepe, S. Raino, R. Rando, M. Razzano, D. Rich, H. F. -W. Sadrozinski, G. Scolieri, G. Spandre, P. Spinelli, M. Sugizaki, H. Tajima, H. Takahashi, T. Takahashi, S. Yoshida, C. Young, M. Ziegler

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 583 ( 1 ) 9 - 13 2007年12月

　概要を見る

The Gamma-ray Large Area Space Telescope represents a great advance in space application of silicon detectors. With a surface of 80 m(2) and about 1 M readout channels it is the largest silicon tracker ever built for a space experiment.
GLAST is an astro-particle mission that will study the mostly unexplored, high energy (20 MeV-300 GeV) spectrum coming from active sources or diffused in the Universe. The detector integration and test phase is complete. The full instrument underwent environmental testing and the spacecraft integration phase has just started: the launch is foreseen in late 2007. In the meanwhile the spare modules are being used for instrument calibration and performance verification employing the CERN accelerator complex. A Calibration Unit has been exposed to photon, electron and hadron beams from a few GeV up to 300 GeV. We report on the status of the instrument and on the calibration campaign. (C) 2007 Elsevier B.V. All rights reserved.

DOI
Design and initial tests of the Tracker-converter of the Gamma-ray Large Area Space Telescope

W. B. Atwood, R. Bagagli, L. Baldini, R. Bellazzini, G. Barbiellini, F. Belli, T. Borden, A. Brez, M. Brigida, G. A. Caliandro, C. Cecchi, J. Cohen-Tanugi, A. De Angelis, P. Drell, C. Favuzzi, Y. Fukazawa, P. Fusco, F. Gargano, S. Germani, R. Giannitrapani, N. Giglietto, F. Giordano, T. Himel, M. Hirayama, R. P. Johnson, H. Katagiri, J. Kataoka, N. Kawai, W. Kroeger, M. Kuss, L. Latronico, F. Longo, F. Loparco, P. Lubrano, M. M. Massai, M. N. Mazziotta, M. Minuti, T. Mizuno, A. Morselli, D. Nelson, M. Nordby, T. Ohsugi, N. Omodei, M. Ozaki, M. Pepe, S. Raino, R. Rando, M. Razzano, D. Rich, H. F. -W. Sadrozinski, G. Scolieri, C. Sgro, G. Spandre, P. Spinelli, M. Sugizaki, H. Tajima, H. Takahashi, T. Takahashi, S. Yoshida, C. Young, M. Ziegler

ASTROPARTICLE PHYSICS 28 ( 4-5 ) 422 - 434 2007年12月

　概要を見る

The Tracker subsystem of the Large Area Telescope (LAT) science instrument of the Gamma-ray Large Area Space Telescope (GLAST) mission has been completed and tested. It is the central detector subsystem of the LAT and serves both to convert an incident gamma-ray into an electron-positron pair and to track the pair in order to measure the gamma-ray direction. It also provides the principal trigger for the LAT. The Tracker uses silicon strip detectors, read out by custom electronics, to detect charged particles. The detectors and electronics are packaged, along with tungsten converter foils, in 16 modular, high-precision carbon-composite structures. It is the largest silicon-strip detector system ever built for launch into space, and its aggressive design emphasizes very low power consumption, passive cooling, low noise, high efficiency, minimal dead area, and a structure that is highly transparent to charged particles. The test program has demonstrated that the system meets or surpasses all of its performance specifications as well as environmental requirements. It is now installed in the completed LAT, which is being prepared for launch in early 2008. (c) 2007 Elsevier B.V. All rights reserved.

DOI
Construction, test and calibration of the GLAST silicon tracker

C. Sgro, W. B. Atwood, L. Baldini, G. Barbiellini, R. Bellazzini, F. Belli, E. Bonamente, T. Borden, J. Bregeon, A. Brez, M. Brigida, G. A. Caliandro, C. Cecchi, J. Cohen-Tanugi, A. De Angelis, P. Drell, C. Favuzzi, Y. Fukazawa, P. Fusco, F. Gargano, S. Germani, N. Giglietto, F. Giordano, T. Himel, M. Hirayama, R. P. Johnson, H. Katagiri, J. Kataoka, N. Kawai, W. Kroeger, M. Kuss, L. Latronico, F. Longo, F. Loparco, P. Lubrano, M. M. Massai, M. N. Mazziotta, M. Minuti, T. Mizuno, A. Morselli, D. Nelson, M. Nordby, T. Ohsugi, N. Omodei, M. Ozaki, M. Pepe, S. Raino, R. Rando, M. Razzano, D. Rich, H. F. -W. Sadrozinski, G. Scolieri, G. Spandre, P. Spinelli, M. Sugizaki, H. Tajima, H. Takahashi, T. Takahashi, S. Yoshida, C. Young, M. Ziegler

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 583 ( 1 ) 9 - 13 2007年12月

　概要を見る

The Gamma-ray Large Area Space Telescope represents a great advance in space application of silicon detectors. With a surface of 80 m(2) and about 1 M readout channels it is the largest silicon tracker ever built for a space experiment.
GLAST is an astro-particle mission that will study the mostly unexplored, high energy (20 MeV-300 GeV) spectrum coming from active sources or diffused in the Universe. The detector integration and test phase is complete. The full instrument underwent environmental testing and the spacecraft integration phase has just started: the launch is foreseen in late 2007. In the meanwhile the spare modules are being used for instrument calibration and performance verification employing the CERN accelerator complex. A Calibration Unit has been exposed to photon, electron and hadron beams from a few GeV up to 300 GeV. We report on the status of the instrument and on the calibration campaign. (C) 2007 Elsevier B.V. All rights reserved.

DOI
Measuring energy dependent polarization in soft gamma-rays using compton scattering in PoGOLite

M. Axelsson, O. Engdegard, F. Ryde, S. Larsson, M. Pearce, L. Hjalmarsdotter, M. Kiss, C. Marini Bettolo, M. Arimoto, C. -I. Bjornsson, P. Carlson, Y. Fukazawa, T. Kamae, Y. Kanai, J. Kataoka, N. Kawal, W. Klamra, G. Madejski, T. Mizuno, J. Ng, H. Tajima, T. Takahashi, T. Tanaka, M. Ueno, G. Varner, K. Yamamoto

ASTROPARTICLE PHYSICS 28 ( 3 ) 327 - 337 2007年11月

　概要を見る

Linear polarization in X-and gamma-rays is an important diagnostic of many astrophysical sources, foremost giving information about their geometry, magnetic fields, and radiation mechanisms. However, very few X-ray polarization measurements have been made, and then only mono-energetic detections, whilst several objects are assumed to have energy dependent polarization signatures. In this paper, we investigate whether detection of energy dependent polarization from cosmic sources is possible using the Compton technique, in particular with the proposed PoGOLite balloon-experiment, in the 25-100 keV range. We use Geant4 simulations of a PoGOLite model and input photon spectra based on Cygnus X-1 and accreting magnetic pulsars (100 mCrab). Effective observing times of 6 and 35 h were simulated, corresponding to a standard and a long duration flight, respectively. Both smooth and sharp energy variations of the polarization are investigated and compared to constant polarization signals using chi-square statistics. We can reject constant polarization, with energy, for the Cygnus X-1 spectrum (in the hard state), if the reflected component is assumed to be completely polarized, whereas the distinction cannot be made for weaker polarization. For the accreting pulsar, constant polarization can be rejected in the case of polarization in a narrow energy band with at least 50% polarization, and similarly for a negative step distribution from 30% to 0% polarization. (c) 2007 Elsevier B.V. All rights reserved.

DOI
Development of wideband X-ray and gamma-ray spectrometer using transmission-type, large-area APD

S. Tanaka, J. Kataoka, Y. Kanai, Y. Yatsu, M. Arimoto, M. Koizumi, N. Kawai, Y. Ishikawa, S. Kawai, N. Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 582 ( 2 ) 562 - 568 2007年11月

　概要を見る

The avalanche photodiode (APD) is a high-performance and compact light sensor recently applied in various fields of experimental physics. Among several types of APDs, the reach-through APD offers an advantage in direct X-ray detection, thanks to its thick depletion layer (>= 100 mu m) in front of the amplification region. This type of APD is also sensitive to weak scintillation light from gamma ray scintillators with a high quantum efficiency of similar to 80% (at lambda similar or equal to 500 nm). In this paper, we propose a novel design of a compact X-rayto-gamma-ray detector widely applicable between 1 keV and several hundreds of keV. The prototype consists of a reach-through APD (transmission type) optically coupled with a cubic CsI(T1) crystal 4 x 4 x 4mm(3) in size. By applying the pulse shape discrimination technique to the APD output, we successfully discriminated the X-ray signals directly detected within the APD (1-40 keV), and gamma ray signals absorbed in a CsI(T1) scintillator (10-800 keV) located immediately behind the APD. Optimum FWHM energy resolutions of 15.1 +/- 0.2%, 6.6 +/- 0.4%, and 7.6 +/- 0.1% were obtained for 5.9 keV X-rays, 32 keV X-rays, and 662 keV gamma rays, respectively, measured at +20 degrees C. This stacked configuration is viable for various future applications in space science and nuclear medicine. (c) 2007 Elsevier B.V. All rights reserved.

DOI
Measuring energy dependent polarization in soft gamma-rays using compton scattering in PoGOLite

M. Axelsson, O. Engdegard, F. Ryde, S. Larsson, M. Pearce, L. Hjalmarsdotter, M. Kiss, C. Marini Bettolo, M. Arimoto, C. -I. Bjornsson, P. Carlson, Y. Fukazawa, T. Kamae, Y. Kanai, J. Kataoka, N. Kawal, W. Klamra, G. Madejski, T. Mizuno, J. Ng, H. Tajima, T. Takahashi, T. Tanaka, M. Ueno, G. Varner, K. Yamamoto

ASTROPARTICLE PHYSICS 28 ( 3 ) 327 - 337 2007年11月

　概要を見る

Linear polarization in X-and gamma-rays is an important diagnostic of many astrophysical sources, foremost giving information about their geometry, magnetic fields, and radiation mechanisms. However, very few X-ray polarization measurements have been made, and then only mono-energetic detections, whilst several objects are assumed to have energy dependent polarization signatures. In this paper, we investigate whether detection of energy dependent polarization from cosmic sources is possible using the Compton technique, in particular with the proposed PoGOLite balloon-experiment, in the 25-100 keV range. We use Geant4 simulations of a PoGOLite model and input photon spectra based on Cygnus X-1 and accreting magnetic pulsars (100 mCrab). Effective observing times of 6 and 35 h were simulated, corresponding to a standard and a long duration flight, respectively. Both smooth and sharp energy variations of the polarization are investigated and compared to constant polarization signals using chi-square statistics. We can reject constant polarization, with energy, for the Cygnus X-1 spectrum (in the hard state), if the reflected component is assumed to be completely polarized, whereas the distinction cannot be made for weaker polarization. For the accreting pulsar, constant polarization can be rejected in the case of polarization in a narrow energy band with at least 50% polarization, and similarly for a negative step distribution from 30% to 0% polarization. (c) 2007 Elsevier B.V. All rights reserved.

DOI
Development of wideband X-ray and gamma-ray spectrometer using transmission-type, large-area APD

S. Tanaka, J. Kataoka, Y. Kanai, Y. Yatsu, M. Arimoto, M. Koizumi, N. Kawai, Y. Ishikawa, S. Kawai, N. Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 582 ( 2 ) 562 - 568 2007年11月

　概要を見る

The avalanche photodiode (APD) is a high-performance and compact light sensor recently applied in various fields of experimental physics. Among several types of APDs, the reach-through APD offers an advantage in direct X-ray detection, thanks to its thick depletion layer (>= 100 mu m) in front of the amplification region. This type of APD is also sensitive to weak scintillation light from gamma ray scintillators with a high quantum efficiency of similar to 80% (at lambda similar or equal to 500 nm). In this paper, we propose a novel design of a compact X-rayto-gamma-ray detector widely applicable between 1 keV and several hundreds of keV. The prototype consists of a reach-through APD (transmission type) optically coupled with a cubic CsI(T1) crystal 4 x 4 x 4mm(3) in size. By applying the pulse shape discrimination technique to the APD output, we successfully discriminated the X-ray signals directly detected within the APD (1-40 keV), and gamma ray signals absorbed in a CsI(T1) scintillator (10-800 keV) located immediately behind the APD. Optimum FWHM energy resolutions of 15.1 +/- 0.2%, 6.6 +/- 0.4%, and 7.6 +/- 0.1% were obtained for 5.9 keV X-rays, 32 keV X-rays, and 662 keV gamma rays, respectively, measured at +20 degrees C. This stacked configuration is viable for various future applications in space science and nuclear medicine. (c) 2007 Elsevier B.V. All rights reserved.

DOI
22pZJ-13 全天X線監視装置MAXI/GSCの現状 : 来年度打ち上げに向けて(22pZJ X線・γ線,宇宙線・宇宙物理領域)

小浜光洋, 鈴木素子, 松岡勝, 川崎一義, 上野史郎, 冨田洋, 石川真木, 宮川雄大, 三原建弘, 磯部直樹, 河合誠之, 片岡淳, 田中議史, 吉田篤正, 根来均, 中島基樹, 森井幹雄

日本物理学会講演概要集 62 ( 2 ) 111 - 111 2007年08月

CiNii
次世代X線天文衛星NeXT搭載,硬X線撮像検出器(HXI)に向けた開発の現状

渡辺伸, 国分紀秀, 佐藤理江, 武田伸一郎, 石川真之介, 小高裕和, 青野博之, 高橋忠幸, 深沢泰司, 安田創, 田中琢也, 西野翔, 中澤知洋, 奥山翔, 田島宏康, 田中孝明, 片岡淳, 寺田幸功, 玉川徹

日本天文学会年会講演予稿集 2007 300 2007年08月

J-GLOBAL
The Suzaku observation of the nucleus of the radio-loud active galaxy Centaurus A: Constraints on abundances of the accreting material

A. Markowitz, T. Takahashi, S. Watanabe, K. Nakazawa, Y. Fukazawa, M. Kokubun, K. Makishima, H. Awaki, A. Bamba, N. Isobe, J. Kataoka, G. Madejski, R. Mushotzky, T. Okajima, A. Ptak, J. N. Reeves, Y. Ueda, T. Yamasaki, T. Yaqoob

ASTROPHYSICAL JOURNAL 665 ( 1 ) 209 - 224 2007年08月

　概要を見る

A Suzaku observation of the nucleus of the radio-loud AGN Centaurus A in 2005 has yielded a broadband spectrum spanning 0.3-250 keV. The net exposure times after screening were 70 ks per X-ray Imaging Spectrometer (XIS) camera, 60.8 ks for the Hard X- ray Detector (HXD) PIN, and 17.1 ks for the HXD GSO. The hard X- rays are fit by two power laws of the same slope, absorbed by columns of 1.5 and 7 x 10(23) cm(-2), respectively. The spectrum is consistent with previous suggestions that the power-law components are X- ray emission from the subparsec VLBI jet and from Bondi accretion at the core, but it is also consistent with a partial-covering interpretation. The soft band is dominated by thermal emission from the diffuse plasma and is fit well by a two-temperature VAPEC model, plus a third power-law component to account for scattered nuclear emission, jet emission, and emission from X- ray binaries and other point sources. Narrow fluorescent emission lines from Fe, Si, S, Ar, Ca, and Ni are detected. The Fe K proportional to line width yields a 200 lt-day lower limit on the distance from the black hole to the line-emitting gas. Fe, Ca, and S K-shell absorption edges are detected. Elemental abundances are constrained via absorption edge depths and strengths of the fluorescent and diffuse plasma emission lines. The high metallicity ([Fe/H] = +0.1) of the circumnuclear material suggests that it could not have originated in the relatively metal-poor outer halo unless enrichment by local star formation has occurred. Relative abundances are consistent with enrichment from Type II and Ia supernovae.

DOI
Low-energy cutoffs and hard X-ray spectra in high-z radio-loud quasars: The Suzaku view of RBS 315

F. Tavecchio, L. Maraschi, G. Ghisellini, J. Kataoka, L. Foschini, R. M. Sambruna, G. Tagliaferri

ASTROPHYSICAL JOURNAL 665 ( 2 ) 980 - 989 2007年08月

　概要を見る

We present the results from the Suzaku observation of the powerful radio-loud quasar RBS 315 (z = 2.69), for which a previous XMM-Newton observation showed an extremely flat X-ray continuum up to 10 keV ( photon index Gamma = 1.26) and indications of strong intrinsic absorption (N-H similar to 10(22) cm(-2), assuming neutral gas). The instrument for hard X-rays, HXD/PIN, allows us a detection of the source up to 50 keV. The broadband continuum (0.5-50 keV) can be well modeled with a power law with slope Gamma = 1.5 (definitively softer than the continuum measured by XMM-Newton) above 1 keV with strong deficit of soft photons. The low-energy cutoff can be well fitted, either with intrinsic absorption ( with column density N-H similar to 10(22) cm(-2) in the quasar rest frame) or with a break in the continuum, with an extremely hard (Gamma = 0.7) power law below 1 keV. We construct the spectral energy distribution of the source, using also optical-UV measurements obtained through a quasi-simultaneous observation with UVOT on board Swift observation. The shape of the SED is similar to that of other flat-spectrumradio quasars (FSRQs) with similar power, making this source an excellent candidate for the detection in gamma-rays by the Gamma-Ray Large Area Space Telescope ( GLAST). We model the SED with the synchrotron inverse Compton model usually applied to FSRQs, showing that the deficit of soft photons can be naturally interpreted as due to an intrinsic curvature of the spectrum near the low-energy end of the IC component, rather than to intrinsic absorption, although the latter possibility cannot be ruled out. We propose that in at least a fraction of the radio-loud QSOs at high redshift, the cutoff in the soft X-ray band can be explained in a similar way. Further studies are required to distinguish between the two alternatives.

DOI
The Suzaku observation of the nucleus of the radio-loud active galaxy Centaurus A: Constraints on abundances of the accreting material

A. Markowitz, T. Takahashi, S. Watanabe, K. Nakazawa, Y. Fukazawa, M. Kokubun, K. Makishima, H. Awaki, A. Bamba, N. Isobe, J. Kataoka, G. Madejski, R. Mushotzky, T. Okajima, A. Ptak, J. N. Reeves, Y. Ueda, T. Yamasaki, T. Yaqoob

ASTROPHYSICAL JOURNAL 665 ( 1 ) 209 - 224 2007年08月

　概要を見る

A Suzaku observation of the nucleus of the radio-loud AGN Centaurus A in 2005 has yielded a broadband spectrum spanning 0.3-250 keV. The net exposure times after screening were 70 ks per X-ray Imaging Spectrometer (XIS) camera, 60.8 ks for the Hard X- ray Detector (HXD) PIN, and 17.1 ks for the HXD GSO. The hard X- rays are fit by two power laws of the same slope, absorbed by columns of 1.5 and 7 x 10(23) cm(-2), respectively. The spectrum is consistent with previous suggestions that the power-law components are X- ray emission from the subparsec VLBI jet and from Bondi accretion at the core, but it is also consistent with a partial-covering interpretation. The soft band is dominated by thermal emission from the diffuse plasma and is fit well by a two-temperature VAPEC model, plus a third power-law component to account for scattered nuclear emission, jet emission, and emission from X- ray binaries and other point sources. Narrow fluorescent emission lines from Fe, Si, S, Ar, Ca, and Ni are detected. The Fe K proportional to line width yields a 200 lt-day lower limit on the distance from the black hole to the line-emitting gas. Fe, Ca, and S K-shell absorption edges are detected. Elemental abundances are constrained via absorption edge depths and strengths of the fluorescent and diffuse plasma emission lines. The high metallicity ([Fe/H] = +0.1) of the circumnuclear material suggests that it could not have originated in the relatively metal-poor outer halo unless enrichment by local star formation has occurred. Relative abundances are consistent with enrichment from Type II and Ia supernovae.

DOI
Low-energy cutoffs and hard X-ray spectra in high-z radio-loud quasars: The Suzaku view of RBS 315

F. Tavecchio, L. Maraschi, G. Ghisellini, J. Kataoka, L. Foschini, R. M. Sambruna, G. Tagliaferri

ASTROPHYSICAL JOURNAL 665 ( 2 ) 980 - 989 2007年08月

　概要を見る

We present the results from the Suzaku observation of the powerful radio-loud quasar RBS 315 (z = 2.69), for which a previous XMM-Newton observation showed an extremely flat X-ray continuum up to 10 keV ( photon index Gamma = 1.26) and indications of strong intrinsic absorption (N-H similar to 10(22) cm(-2), assuming neutral gas). The instrument for hard X-rays, HXD/PIN, allows us a detection of the source up to 50 keV. The broadband continuum (0.5-50 keV) can be well modeled with a power law with slope Gamma = 1.5 (definitively softer than the continuum measured by XMM-Newton) above 1 keV with strong deficit of soft photons. The low-energy cutoff can be well fitted, either with intrinsic absorption ( with column density N-H similar to 10(22) cm(-2) in the quasar rest frame) or with a break in the continuum, with an extremely hard (Gamma = 0.7) power law below 1 keV. We construct the spectral energy distribution of the source, using also optical-UV measurements obtained through a quasi-simultaneous observation with UVOT on board Swift observation. The shape of the SED is similar to that of other flat-spectrumradio quasars (FSRQs) with similar power, making this source an excellent candidate for the detection in gamma-rays by the Gamma-Ray Large Area Space Telescope ( GLAST). We model the SED with the synchrotron inverse Compton model usually applied to FSRQs, showing that the deficit of soft photons can be naturally interpreted as due to an intrinsic curvature of the spectrum near the low-energy end of the IC component, rather than to intrinsic absorption, although the latter possibility cannot be ruled out. We propose that in at least a fraction of the radio-loud QSOs at high redshift, the cutoff in the soft X-ray band can be explained in a similar way. Further studies are required to distinguish between the two alternatives.

DOI
Probing the disk-jet connection of the radio galaxy 3C 120 observed with Suzaku

Jun Kataoka, James N. Reeves, Kazushi Iwasawa, Alex G. Markowitz, Richard F. Mushotzky, Makoto Arimoto, Tadayuki Takahashi, Yoshihiro Tsubuku, Masayoshi Ushio, Shin Watanabe, Luigi C. Gallo, Greg M. Madejski, Yuichi Terashima, Naoki Isobe, Makoto S. Tashiro, Takayoshi Kohmura

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 ( 2 ) 279 - 297 2007年04月

　概要を見る

We report on deep (40 ks x 4) observations of the bright broad line radio galaxy 3C 120 using Suzaku. The observations were spaced one week apart, and sampled a range of continuum fluxes. An excellent broadband spectrum was obtained over two decades of frequency (0.6 to 50 keV) within each 40 ks exposure. We clearly resolved the iron K emission-line complex, finding that it consists of a narrow K alpha core (sigma similar or equal to 110 eV or an EW of 60 eV), a 6.9 keV line, and an underlying broad iron line. Our confirmation of the broad line contrasts with the XMM-Newton observation in 2003, where the broad line was not required. The most natural interpretation of the broadline is iron Kline emission from a face-on accretion disk that is truncated at similar to 10 r(g). Above 10 keV, a relatively weak Compton hump was detected (reflection fraction of R similar or equal to 0.6), superposed on the primary X-ray continuum of Gamma similar or equal to 1.75. Thanks to the good photon statistics and low background of the Suzaku data, we clearly confirm the spectral evolution of 3C 120, whereby the variability amplitude decreases with increasing energy. More strikingly, we discovered that the variability is caused by a steep power-law component of Gamma similar or equal to 2.7, possibly related to non-thermal jet emission. We discuss our findings in the context of similarities and differences between radio-loud/quiet objects.

DOI
Probing the disk-jet connection of the radio galaxy 3C 120 observed with Suzaku

Jun Kataoka, James N. Reeves, Kazushi Iwasawa, Alex G. Markowitz, Richard F. Mushotzky, Makoto Arimoto, Tadayuki Takahashi, Yoshihiro Tsubuku, Masayoshi Ushio, Shin Watanabe, Luigi C. Gallo, Greg M. Madejski, Yuichi Terashima, Naoki Isobe, Makoto S. Tashiro, Takayoshi Kohmura

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 ( 2 ) 279 - 297 2007年04月

　概要を見る

We report on deep (40 ks x 4) observations of the bright broad line radio galaxy 3C 120 using Suzaku. The observations were spaced one week apart, and sampled a range of continuum fluxes. An excellent broadband spectrum was obtained over two decades of frequency (0.6 to 50 keV) within each 40 ks exposure. We clearly resolved the iron K emission-line complex, finding that it consists of a narrow K alpha core (sigma similar or equal to 110 eV or an EW of 60 eV), a 6.9 keV line, and an underlying broad iron line. Our confirmation of the broad line contrasts with the XMM-Newton observation in 2003, where the broad line was not required. The most natural interpretation of the broadline is iron Kline emission from a face-on accretion disk that is truncated at similar to 10 r(g). Above 10 keV, a relatively weak Compton hump was detected (reflection fraction of R similar or equal to 0.6), superposed on the primary X-ray continuum of Gamma similar or equal to 1.75. Thanks to the good photon statistics and low background of the Suzaku data, we clearly confirm the spectral evolution of 3C 120, whereby the variability amplitude decreases with increasing energy. More strikingly, we discovered that the variability is caused by a steep power-law component of Gamma similar or equal to 2.7, possibly related to non-thermal jet emission. We discuss our findings in the context of similarities and differences between radio-loud/quiet objects.

DOI
Probing the disk-jet connection of the radio galaxy 3C 120 observed with Suzaku

Jun Kataoka, James N. Reeves, Kazushi Iwasawa, Alex G. Markowitz, Richard F. Mushotzky, Makoto Arimoto, Tadayuki Takahashi, Yoshihiro Tsubuku, Masayoshi Ushio, Shin Watanabe, Luigi C. Gallo, Greg M. Madejski, Yuichi Terashima, Naoki Isobe, Makoto S. Tashiro, Takayoshi Kohmura

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 ( 2 ) 279 - 297 2007年04月

　概要を見る

We report on deep (40 ks x 4) observations of the bright broad line radio galaxy 3C 120 using Suzaku. The observations were spaced one week apart, and sampled a range of continuum fluxes. An excellent broadband spectrum was obtained over two decades of frequency (0.6 to 50 keV) within each 40 ks exposure. We clearly resolved the iron K emission-line complex, finding that it consists of a narrow K alpha core (sigma similar or equal to 110 eV or an EW of 60 eV), a 6.9 keV line, and an underlying broad iron line. Our confirmation of the broad line contrasts with the XMM-Newton observation in 2003, where the broad line was not required. The most natural interpretation of the broadline is iron Kline emission from a face-on accretion disk that is truncated at similar to 10 r(g). Above 10 keV, a relatively weak Compton hump was detected (reflection fraction of R similar or equal to 0.6), superposed on the primary X-ray continuum of Gamma similar or equal to 1.75. Thanks to the good photon statistics and low background of the Suzaku data, we clearly confirm the spectral evolution of 3C 120, whereby the variability amplitude decreases with increasing energy. More strikingly, we discovered that the variability is caused by a steep power-law component of Gamma similar or equal to 2.7, possibly related to non-thermal jet emission. We discuss our findings in the context of similarities and differences between radio-loud/quiet objects.

DOI
Probing the disk-jet connection of the radio galaxy 3C 120 observed with Suzaku

Jun Kataoka, James N. Reeves, Kazushi Iwasawa, Alex G. Markowitz, Richard F. Mushotzky, Makoto Arimoto, Tadayuki Takahashi, Yoshihiro Tsubuku, Masayoshi Ushio, Shin Watanabe, Luigi C. Gallo, Greg M. Madejski, Yuichi Terashima, Naoki Isobe, Makoto S. Tashiro, Takayoshi Kohmura

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 ( 2 ) 279 - 297 2007年04月

　概要を見る

We report on deep (40 ks x 4) observations of the bright broad line radio galaxy 3C 120 using Suzaku. The observations were spaced one week apart, and sampled a range of continuum fluxes. An excellent broadband spectrum was obtained over two decades of frequency (0.6 to 50 keV) within each 40 ks exposure. We clearly resolved the iron K emission-line complex, finding that it consists of a narrow K alpha core (sigma similar or equal to 110 eV or an EW of 60 eV), a 6.9 keV line, and an underlying broad iron line. Our confirmation of the broad line contrasts with the XMM-Newton observation in 2003, where the broad line was not required. The most natural interpretation of the broadline is iron Kline emission from a face-on accretion disk that is truncated at similar to 10 r(g). Above 10 keV, a relatively weak Compton hump was detected (reflection fraction of R similar or equal to 0.6), superposed on the primary X-ray continuum of Gamma similar or equal to 1.75. Thanks to the good photon statistics and low background of the Suzaku data, we clearly confirm the spectral evolution of 3C 120, whereby the variability amplitude decreases with increasing energy. More strikingly, we discovered that the variability is caused by a steep power-law component of Gamma similar or equal to 2.7, possibly related to non-thermal jet emission. We discuss our findings in the context of similarities and differences between radio-loud/quiet objects.

DOI
26aSF-8 「すざく」とH.E.S.S/MAGICによるTeVブレーザーの多波長同時観測(26aSF X線・γ線,宇宙線・宇宙物理領域)

牛尾雅佳, 内山泰伸, 高橋忠幸, 渡辺伸, 田代信, 矢治裕一, 片岡淳, 林田将明, Aharonian F., Costamante L., Wagner S., MAGICチーム, H.E.S.Sチーム

日本物理学会講演概要集 62 ( 1 ) 95 - 95 2007年02月

CiNii
Hole multiplication in a reverse-type avalanche photodiode

Mitsuhiro Sato, Takayuki Yanagida, Akira Yoshikawa, Yoichi Yatsu, Jun Kataoka, Fumio Saito

2007 IEEE NUCLEAR SCIENCE SYMPOSIUM CONFERENCE RECORD, VOLS 1-11 1486 - + 2007年 [査読有り]

　概要を見る

This paper reports on hole multiplication processes, detected in a reverse-type avalanche photodiode (APD), Hamamatsu Photonics type S8664-55, which has a light sensitive area of 5 x 5 mm and a depletion layer thickness of similar to 40 mu m. When the APD was irradiated from a Am-241 isotope, the 13.9 keV and 17.6 keV X-rays produced spectral peaks, whose pulse height depended strongly on the bias voltage, whereas 57.5 keV photons produced another peak, whose the pulse height was much less bias sensitive. The former are identified with electron multiplication signals, whereas the latter with those due to hole multiplication. By measuring the electron and hole multiplication gains as a function of the bias voltage, the ratio of hole and electron ionization probabilities was determined as 0.0130 +/- 0.0010 at 20 degrees C, and 0.0153 +/- 0.0010 at -20 degrees C.
シミュレーションを用いた次世代ガンマ線天文衛星GLASTの感度評価

吉田広明, 大杉節, 深沢泰司, 片桐秀明, 水野恒史, 高橋弘充, 高橋拓也, 釜江常好, 田島宏康, 田中孝明, 河合誠之, 片岡淳, 植野優, 高橋忠幸, 尾崎正伸

日本天文学会年会講演予稿集 2007 2007年

J-GLOBAL
Beam test of a prototype phoswich detector assembly for the PoGOLite astronomical soft gamma-ray polarimeter

Y. Kanai, M. Ueno, J. Kataoka, M. Arimoto, N. Kawai, K. Yamamoto, T. Mizuno, Y. Fukazawa, M. Kiss, T. Ylinen, C. Marini Bettolo, P. Carlson, W. Klamra, M. Pearce, P. Chen, B. Craig, T. Kamae, G. Madejski, J. S. T. Ng, R. Rogers, H. Tajima, T. S. Thurston, Y. Saito, T. Takahashi, S. Gunji, C-I Bjornsson, S. Larsson, F. Ryde, G. Bogaert, S. Kishimoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 570 ( 1 ) 61 - 71 2007年01月

　概要を見る

We report about the beam test on a prototype of the balloon-based astronomical soft gamma-ray polarimeter, PoGOLite (Polarized Gamma-ray Observer-Light Version) conducted at KEK Photon Factory, a synchrotron radiation facility in Japan. The synchrotron beam was set at 30, 50, and 70 keV and its polarization was monitored by a calibrated polarimeter. The goal of the experiment was to validate the flight design of the polarimeter. PoGOLite is designed to measure polarization by detecting a Compton scattering and the subsequent photo-absorption in an array of 217 well-type phoswich detector cells (PDCs). The test setup included a first flight model PDC and a front-end electronics to select and reconstruct valid Compton scattering events. The experiment has verified that the flight PDC can detect recoil electrons and select valid Compton scattering events down to 30 keV from background. The measure azimuthal modulations (34.4%, 35.8% and 37.2% at 30, 50, and 70 keV, respectively) agreed within 10% (relative) with the predictions by Geant4 implemented with dependence on the initial and final photon polarizations. (c) 2006 Elsevier B.V. All rights reserved.

DOI
Wide Range Multifrequency Observations of Northern TeV Blazars

Rugamer

Astronomische Nachrichten 328 623 2007年
The X-ray observatory Suzaku

Kazuhisa Mitsuda, Mark Bautz, Hajime Inoue, Richard L. Kelley, Katsuji Koyama, Hideyo Kunieda, Kazuo Makshima, Yoshiaki Ogawara, Robert Petre, Tadayuki Takahashi, Hiroshi Tsunemi, Nicholas E. White, Naohisa Anabuki, Lorella Angelini, Keith Arnaud, Hisamitsu Awaki, Aya Bamba, Kevin Boyce, Gregory V. Brown, Kai-Wing Chan, Jean Cottam, Tadayasu Dotanli, John Doty, Ken Ebisawa, Yuichiro Ezoe, Andrew C. Fabian, Enectali Figueroa, Ryuichi Fujimoto, Yasushi Fukazawa, Tae Furusho, Akihiro Furuzawa, Keith Gendreau, Richard E. Griffiths, Yoshito Haba, Kenji Hamaguchi, Ilana Harrus, Gunther Hasinger, Isamu Hatsukade, Kiyoshi Hayashida, Patrick J. Henry, Junko S. Hiraga, Stephen S. Holt, Ann Hornschemeier, John P. Hughes, Una Hwang, Manabu Ishida, Yoshitaka Ishisaki, Naoki Isobe, Masayuki Itoh, Naoko Iyomoto, Steven M. Kahn, Tuneyoshi Kamae, Hideaki Katagiri, Jun Kataoka, Haruyoshi Katayama, Nobuyuki Kawai, Caroline Kilbourne, Kenzo Kinugasa, Steve Kissel, Shunji Kitamoto, Mitsuhiro Kohama, Takayoshi Kohmura, Motohide Kokubun, Taro Kotani, Jun'ichi Kotoku, Aya Kubota, Greg M. Madejski, Yoshitomo Maeda, Fumiyoshi Makino, Alex Markowitz, Chiho Matsumoto, Hironori Matsumoto, Masaru Matsuoka, Kyoko Matsushita, Dan McCammon, Tatehiko Mihara, Kazutami Misaki, Emi Miyata, Tsunefumi Mizuno, Koji Mori, Hideyuki Mori, Mikio Morii, Harvey Moseley, Koji Mukai, Hiroshi Murakami, Toshio Murakami, Richard Mushotzky, Fumiaki Nagase, Masaaki Namiki, Hitoshi Negoro, Kazubiro Nakazawa, John A. Nousek, Takashi Okajima, Yasushi Ogasaka, Takaya Ohashi, Tai Oshima, Naomi Ota, Masanobu Ozaki, Hideki Ozawa, Arvind N. Parmar, William D. Pence, F. Scott Porter, James N. Reeves, George R. Ricker, Ikuya Sakurai, Wilton T. Sanders, Atsushi Senda, Peter Serlemitsos, Ryo Shibata, Yang Soong, Randall Smith, Motoko Suzuki, Andrew E. Szymkowiak, Hiromitsu Takahashi, Torn Tamagawa, Keisuke Tamura, Takayuki Tamura, Yasuo Tanaka, Makoto Tashiro, Yuzuru Tawara, Yukikatsu Terada, Yuichi Terashima, Hiroshi Tomida, Ken'ichi Torii, Yohko Tsuboi, Masahiro Tsujimoto, Takeshi Go Tsuru, Martin J. L. Turner, Yoshihiro Ueda, Shiro Ueno, Masaru Ueno, Shin'ichiro Uno, Yuji Urata, Shin Watanabe, Norimasa Yamamoto, Kazutaka Yamaoka, Noriko Y. Yamasaki, Koujun Yamashita, Makoto Yamauchi, Shigeo Yamauchi, Tahir Yaqoob, Daisuke Yonetoku, Atsumasa Yoshida

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 ( 1 SPEC. ISS. ) S1 - S7 2007年01月

　概要を見る

High-sensitivity wide-band X-ray spectroscopy is the key feature of the Suzaku X-ray observatory, launched on 2005 July 10. This paper summarizes the spacecraft, in-orbit performance, operations, and data processing that are related to observations. The scientific instruments, the high-throughput X-ray telescopes, X-ray CCD cameras, non-imaging hard X-ray detector are also described.

DOI
Suzaku observations of HESS J1616-508: Evidence for a dark particle accelerator

Hironori Matsumoto, Masaru Ueno, Aya Bamba, Yoshiaki Hyodo, Hideyuki Mori, Hideki Uchiyama, Takeshi Go Tsuru, Katsuji Koyama, Jun Kataoka, Hideaki Katagiri, Tadayuki Takahashi, Junko Hiraga, Shigeo Yamauchi, John P. Hughes, Atsushi Senda, Motohide Kokubun, Takayoshi Kohmura, Frederick S. Porter

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 ( 1 SPEC. ISS. ) S199 - S208 2007年01月

　概要を見る

We observed the bright unidentified TeV gamma-ray source HESS J1616-508 with the X-ray Imaging Spectrometers onboard the Suzaku satellite. No X-ray counterpart was found to a limiting flux of 3.1 x 10(-13) erg s(-1) cm(-2) in the 2-10 keV band, which is some 60-times below the gamma-ray flux in the 1-10 TeV band. This object is bright in TeV gamma-rays, but very dim in the X-ray band, and thus is one of the best examples in the Galaxy of a "dark particle accelerator." We also detected soft thermal emission with kT similar to 0.3-0.6 keV near the location of HESS J1616-508. This may be due to a dust-grain scattering halo from the nearby bright supernova remnant RCW 103.

DOI
Iron and nickel line diagnostics for the Galactic Center diffuse emission

Katsuji Koyama, Yoshiaki Hyodo, Tatsuya Inui, Hiroshi Nakajima, Hironori Matsumoto, Takeshi Go Tsuru, Tadayuki Takahashi, Yoshitomo Maeda, Noriko Y. Yamazaki, Hiroshi Murakami, Shigeo Yamauchi, Yohko Tsuboi, Atsushi Senda, Jun Kataoka, Hiromitsu Takahashi, Stephen S. Holt, Gregory V. Brown

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 S245 - S255 2007年01月

　概要を見る

We have observed the diffuse X-ray emission from the Galactic Center (GC) using the X-ray Imaging Spectrometer (XIS) on Suzaku. The high-energy resolution and the low-background orbit provided excellent spectra of the GC diffuse X-rays (GCDX). The XIS found many emission lines in the GCDX near the energy of K-shell transitions of iron and nickel. The most pronounced features are Fe I K alpha at 6.4 keV and K-shell absorption edge at 7.1 keV, which are from neutral and/or low ionization states of iron, and the K-shell lines at 6.7 keV and 6.9 keV from He-like (Fe XXV K alpha) and hydrogenic (Fe XXVI Ly alpha) ions of iron. In addition, K alpha lines from neutral or low ionization nickel (Ni I K alpha) and He-like nickel (Ni XXVII K alpha), Fe I K beta, Fe XXV K beta, Fe XXVI Ly beta, Fe XXV K gamma, and Fe XXVI Ly gamma were detected for the first time. The line center energies and widths of Fe XXV K alpha and Fe XXVI Ly alpha favor a collisional excitation plasma for the origin of the GCDX. The electron temperature determined from the line flux ratio of Fe XXV K alpha/Fe XXV K beta is similar to the ionization temperature determined from that of Fe XXV K alpha/Fe XXVI Ly alpha. Thus it would appear that the GCDX plasma is close to ionization equilibrium. The 6.7 keV flux and temperature distribution to the galactic longitude is smooth and monotonic, in contrast to the integrated point source flux distribution. These facts support the hypothesis that the GCDX is truly diffuse emission rather than the integration of the outputs of a large number of unresolved point sources. In addition, our results demonstrate that the chemical composition of Fe in the interstellar gas near the GC is constrained to be about 3.5 times solar abundance.

DOI
Hard X-ray Detector (HXD) on board Suzaku

Tadayuki Takahashi, Keiichi Abe, Manabu Endo, Yasuhiko Endo, Yuuichiro Ezoe, Yasushi Fukazawa, Masahito Hamaya, Shinya Hirakuri, Soojing Hong, Michihiro Horii, Hokuto Inoue, Naoki Isobe, Takeshi Itoh, Naoko Iyomoto, Tuneyoshi Kamae, Daisuke Kasama, Jun Kataoka, Hiroshi Kato, Madoka Kawaharada, Naomi Kawano, Kengo Kawashima, Satoshi Kawasoe, Tetsuichi Kishishita, Takao Kitaguch, Yoshihito Kobayashi, Motohide Kokubun, Jun'ichi Kotoku, Manabu Kouda, Aya Kubota, Yoshikatsu Kuroda, Greg Madejski, Kazuo Makishima, Kazunori Masukama, Yukari Matsumoto, Takefumi Mitani, Ryohei Miyawaki, Tsunefumi Mizuno, Kunishiro Mori, Masanori Mori, Mio Murashima, Toshio Murakami, Kazuhiro Nakazawa, Hisako Niko, Masaharu Nomachi, Yuu Okada, Masanori Ohno, Kousuke Oonuki, Naomi Ota, Hideki Ozawa, Goro Sato, Shingo Shinoda, Masahiko Sugiho, Masaya Suzuki, Koji Taguchi, Hiromitsu Takahashi, Isao Takahashi, Shin'ichiro Takeda, Ken-ichi Tamura, Takayuki Tamura, Takaaki Tanaka, Chiharu Tanihata, Makoto Tashiro, Yukikatsu Terada, Shin'ya Tominaga, Yasunobu Uchiyama, Shin Watanabe, Kazutaka Yamaoka, Takayuki Yanagida, Daisuke Yonetoku

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 S35 - S51 2007年01月

　概要を見る

The Hard X-ray Detector (HXD) on board Suzaku covers a wide energy range from 10 keV to 600 keV by the combination of silicon PIN diodes and GSO scintillators. The HXD is designed to achieve an extremely low in-orbit background based on a combination of new techniques, including the concept of a well-type active shield counter. With an effective area of 142 cm(2) at 20 keV and 273 cm(2) at 150 keV, the background level at sea level reached similar to 1 X 10(-5) cts s(-1) cm(-2) keV(-1) at 30 keV for the PIN diodes, and similar to 2 X 10(-5) cts s(-1) cm(-2) keV(-1) at 100 keV, and similar to 7 X 10(-6) cts s(-1) cm(-2) keV(-1) at 200 keV for the phoswich counter. Tight active shielding of the HXD results in a large array of guard counters surrounding the main detector parts. These anti-coincidence counters, made of similar to 4 cm thick BGO crystals, have a large effective area for sub-MeV to MeV gamma-rays. They work as an excellent gamma-ray burst monitor with limited angular resolution (similar to 5 degrees). The on-board signal-processing system and the data transmitted to the ground are also described.

DOI
A Suzaku observation of the low-ionization Fe-Line emission from RCW 86

Masaru Ueno, Rie Sato, Jun Kataoka, Aya Bamba, Ilana Harrus, Junko Hiraga, John P. Hughes, Caroline A. Kilbourne, Katsuji Koyama, Motohide Kokubun, Hiroshi Nakajima, Masanobu Ozaki, Robert Petre, Tadayuki Takahashi, Takaaki Tanaka, Hiroshi Tomida, Hiroya Yaniaguchi

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 ( 1 SPEC. ISS. ) S171 - S176 2007年01月

　概要を見る

The newly operational X-ray satellite Suzaku observed the southwestern quadrant of the supernova remnant RCW 86 in 2006 February to study the nature of the 6.4 keV emission line first detected with the Advanced Satellite for Cosmology and Astronomy (ASCA). The new data confirm the existence of the line, localizing it for the first time; most of the line emission is adjacent and interior to the forward shock, and not at the locus of the continuum hard emission. We also report the first detection of a 7.1 keV line, which we interpret as K beta emission from low-ionization iron. The Fe K line features are consistent with a non-equilibrium plasma of Fe-rich ejecta with n(e)t less than or similar to 10(9) cm(-3) s and kT(e) similar to 5 keV. This combination of low n(e)t and high kT(e) suggests collisionless electron heating in an SNR shock. The Fe K alpha line shows evidence for intrinsic broadening, with a width of 47 (34-59) eV (99% error region). The difference in the spatial distributions of the hard continuum above 3 keV and the Fe K line emission supports a synchrotron origin for the hard continuum.

DOI
Beam test of a prototype phoswich detector assembly for the PoGOLite astronomical soft gamma-ray polarimeter

Y. Kanai, M. Ueno, J. Kataoka, M. Arimoto, N. Kawai, K. Yamamoto, T. Mizuno, Y. Fukazawa, M. Kiss, T. Ylinen, C. Marini Bettolo, P. Carlson, W. Klamra, M. Pearce, P. Chen, B. Craig, T. Kamae, G. Madejski, J. S. T. Ng, R. Rogers, H. Tajima, T. S. Thurston, Y. Saito, T. Takahashi, S. Gunji, C-I Bjornsson, S. Larsson, F. Ryde, G. Bogaert, S. Kishimoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 570 ( 1 ) 61 - 71 2007年01月

　概要を見る

We report about the beam test on a prototype of the balloon-based astronomical soft gamma-ray polarimeter, PoGOLite (Polarized Gamma-ray Observer-Light Version) conducted at KEK Photon Factory, a synchrotron radiation facility in Japan. The synchrotron beam was set at 30, 50, and 70 keV and its polarization was monitored by a calibrated polarimeter. The goal of the experiment was to validate the flight design of the polarimeter. PoGOLite is designed to measure polarization by detecting a Compton scattering and the subsequent photo-absorption in an array of 217 well-type phoswich detector cells (PDCs). The test setup included a first flight model PDC and a front-end electronics to select and reconstruct valid Compton scattering events. The experiment has verified that the flight PDC can detect recoil electrons and select valid Compton scattering events down to 30 keV from background. The measure azimuthal modulations (34.4%, 35.8% and 37.2% at 30, 50, and 70 keV, respectively) agreed within 10% (relative) with the predictions by Geant4 implemented with dependence on the initial and final photon polarizations. (c) 2006 Elsevier B.V. All rights reserved.

DOI
Wide Range Multifrequency Observations of Northern TeV Blazars

Rugamer

Astronomische Nachrichten 328 623 2007年
The X-ray observatory Suzaku

Kazuhisa Mitsuda, Mark Bautz, Hajime Inoue, Richard L. Kelley, Katsuji Koyama, Hideyo Kunieda, Kazuo Makshima, Yoshiaki Ogawara, Robert Petre, Tadayuki Takahashi, Hiroshi Tsunemi, Nicholas E. White, Naohisa Anabuki, Lorella Angelini, Keith Arnaud, Hisamitsu Awaki, Aya Bamba, Kevin Boyce, Gregory V. Brown, Kai-Wing Chan, Jean Cottam, Tadayasu Dotanli, John Doty, Ken Ebisawa, Yuichiro Ezoe, Andrew C. Fabian, Enectali Figueroa, Ryuichi Fujimoto, Yasushi Fukazawa, Tae Furusho, Akihiro Furuzawa, Keith Gendreau, Richard E. Griffiths, Yoshito Haba, Kenji Hamaguchi, Ilana Harrus, Gunther Hasinger, Isamu Hatsukade, Kiyoshi Hayashida, Patrick J. Henry, Junko S. Hiraga, Stephen S. Holt, Ann Hornschemeier, John P. Hughes, Una Hwang, Manabu Ishida, Yoshitaka Ishisaki, Naoki Isobe, Masayuki Itoh, Naoko Iyomoto, Steven M. Kahn, Tuneyoshi Kamae, Hideaki Katagiri, Jun Kataoka, Haruyoshi Katayama, Nobuyuki Kawai, Caroline Kilbourne, Kenzo Kinugasa, Steve Kissel, Shunji Kitamoto, Mitsuhiro Kohama, Takayoshi Kohmura, Motohide Kokubun, Taro Kotani, Jun'ichi Kotoku, Aya Kubota, Greg M. Madejski, Yoshitomo Maeda, Fumiyoshi Makino, Alex Markowitz, Chiho Matsumoto, Hironori Matsumoto, Masaru Matsuoka, Kyoko Matsushita, Dan McCammon, Tatehiko Mihara, Kazutami Misaki, Emi Miyata, Tsunefumi Mizuno, Koji Mori, Hideyuki Mori, Mikio Morii, Harvey Moseley, Koji Mukai, Hiroshi Murakami, Toshio Murakami, Richard Mushotzky, Fumiaki Nagase, Masaaki Namiki, Hitoshi Negoro, Kazubiro Nakazawa, John A. Nousek, Takashi Okajima, Yasushi Ogasaka, Takaya Ohashi, Tai Oshima, Naomi Ota, Masanobu Ozaki, Hideki Ozawa, Arvind N. Parmar, William D. Pence, F. Scott Porter, James N. Reeves, George R. Ricker, Ikuya Sakurai, Wilton T. Sanders, Atsushi Senda, Peter Serlemitsos, Ryo Shibata, Yang Soong, Randall Smith, Motoko Suzuki, Andrew E. Szymkowiak, Hiromitsu Takahashi, Torn Tamagawa, Keisuke Tamura, Takayuki Tamura, Yasuo Tanaka, Makoto Tashiro, Yuzuru Tawara, Yukikatsu Terada, Yuichi Terashima, Hiroshi Tomida, Ken'ichi Torii, Yohko Tsuboi, Masahiro Tsujimoto, Takeshi Go Tsuru, Martin J. L. Turner, Yoshihiro Ueda, Shiro Ueno, Masaru Ueno, Shin'ichiro Uno, Yuji Urata, Shin Watanabe, Norimasa Yamamoto, Kazutaka Yamaoka, Noriko Y. Yamasaki, Koujun Yamashita, Makoto Yamauchi, Shigeo Yamauchi, Tahir Yaqoob, Daisuke Yonetoku, Atsumasa Yoshida

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 S1 - S7 2007年01月

　概要を見る

High-sensitivity wide-band X-ray spectroscopy is the key feature of the Suzaku X-ray observatory, launched on 2005 July 10. This paper summarizes the spacecraft, in-orbit performance, operations, and data processing that are related to observations. The scientific instruments, the high-throughput X-ray telescopes, X-ray CCD cameras, non-imaging hard X-ray detector are also described.

DOI
Suzaku observations of HESS J1616-508: Evidence for a dark particle accelerator

Hironori Matsumoto, Masaru Ueno, Aya Bamba, Yoshiaki Hyodo, Hideyuki Mori, Hideki Uchiyama, Takeshi Go Tsuru, Katsuji Koyama, Jun Kataoka, Hideaki Katagiri, Tadayuki Takahashi, Junko Hiraga, Shigeo Yamauchi, John P. Hughes, Atsushi Senda, Motohide Kokubun, Takayoshi Kohmura, Frederick S. Porter

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 S199 - S208 2007年01月

　概要を見る

We observed the bright unidentified TeV gamma-ray source HESS J1616-508 with the X-ray Imaging Spectrometers onboard the Suzaku satellite. No X-ray counterpart was found to a limiting flux of 3.1 x 10(-13) erg s(-1) cm(-2) in the 2-10 keV band, which is some 60-times below the gamma-ray flux in the 1-10 TeV band. This object is bright in TeV gamma-rays, but very dim in the X-ray band, and thus is one of the best examples in the Galaxy of a "dark particle accelerator." We also detected soft thermal emission with kT similar to 0.3-0.6 keV near the location of HESS J1616-508. This may be due to a dust-grain scattering halo from the nearby bright supernova remnant RCW 103.

DOI
Iron and nickel line diagnostics for the Galactic Center diffuse emission

Katsuji Koyama, Yoshiaki Hyodo, Tatsuya Inui, Hiroshi Nakajima, Hironori Matsumoto, Takeshi Go Tsuru, Tadayuki Takahashi, Yoshitomo Maeda, Noriko Y. Yamazaki, Hiroshi Murakami, Shigeo Yamauchi, Yohko Tsuboi, Atsushi Senda, Jun Kataoka, Hiromitsu Takahashi, Stephen S. Holt, Gregory V. Brown

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 S245 - S255 2007年01月

　概要を見る

We have observed the diffuse X-ray emission from the Galactic Center (GC) using the X-ray Imaging Spectrometer (XIS) on Suzaku. The high-energy resolution and the low-background orbit provided excellent spectra of the GC diffuse X-rays (GCDX). The XIS found many emission lines in the GCDX near the energy of K-shell transitions of iron and nickel. The most pronounced features are Fe I K alpha at 6.4 keV and K-shell absorption edge at 7.1 keV, which are from neutral and/or low ionization states of iron, and the K-shell lines at 6.7 keV and 6.9 keV from He-like (Fe XXV K alpha) and hydrogenic (Fe XXVI Ly alpha) ions of iron. In addition, K alpha lines from neutral or low ionization nickel (Ni I K alpha) and He-like nickel (Ni XXVII K alpha), Fe I K beta, Fe XXV K beta, Fe XXVI Ly beta, Fe XXV K gamma, and Fe XXVI Ly gamma were detected for the first time. The line center energies and widths of Fe XXV K alpha and Fe XXVI Ly alpha favor a collisional excitation plasma for the origin of the GCDX. The electron temperature determined from the line flux ratio of Fe XXV K alpha/Fe XXV K beta is similar to the ionization temperature determined from that of Fe XXV K alpha/Fe XXVI Ly alpha. Thus it would appear that the GCDX plasma is close to ionization equilibrium. The 6.7 keV flux and temperature distribution to the galactic longitude is smooth and monotonic, in contrast to the integrated point source flux distribution. These facts support the hypothesis that the GCDX is truly diffuse emission rather than the integration of the outputs of a large number of unresolved point sources. In addition, our results demonstrate that the chemical composition of Fe in the interstellar gas near the GC is constrained to be about 3.5 times solar abundance.

DOI
Hard X-ray Detector (HXD) on board Suzaku

Tadayuki Takahashi, Keiichi Abe, Manabu Endo, Yasuhiko Endo, Yuuichiro Ezoe, Yasushi Fukazawa, Masahito Hamaya, Shinya Hirakuri, Soojing Hong, Michihiro Horii, Hokuto Inoue, Naoki Isobe, Takeshi Itoh, Naoko Iyomoto, Tuneyoshi Kamae, Daisuke Kasama, Jun Kataoka, Hiroshi Kato, Madoka Kawaharada, Naomi Kawano, Kengo Kawashima, Satoshi Kawasoe, Tetsuichi Kishishita, Takao Kitaguch, Yoshihito Kobayashi, Motohide Kokubun, Jun'ichi Kotoku, Manabu Kouda, Aya Kubota, Yoshikatsu Kuroda, Greg Madejski, Kazuo Makishima, Kazunori Masukama, Yukari Matsumoto, Takefumi Mitani, Ryohei Miyawaki, Tsunefumi Mizuno, Kunishiro Mori, Masanori Mori, Mio Murashima, Toshio Murakami, Kazuhiro Nakazawa, Hisako Niko, Masaharu Nomachi, Yuu Okada, Masanori Ohno, Kousuke Oonuki, Naomi Ota, Hideki Ozawa, Goro Sato, Shingo Shinoda, Masahiko Sugiho, Masaya Suzuki, Koji Taguchi, Hiromitsu Takahashi, Isao Takahashi, Shin'ichiro Takeda, Ken-ichi Tamura, Takayuki Tamura, Takaaki Tanaka, Chiharu Tanihata, Makoto Tashiro, Yukikatsu Terada, Shin'ya Tominaga, Yasunobu Uchiyama, Shin Watanabe, Kazutaka Yamaoka, Takayuki Yanagida, Daisuke Yonetoku

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 S35 - S51 2007年01月

　概要を見る

The Hard X-ray Detector (HXD) on board Suzaku covers a wide energy range from 10 keV to 600 keV by the combination of silicon PIN diodes and GSO scintillators. The HXD is designed to achieve an extremely low in-orbit background based on a combination of new techniques, including the concept of a well-type active shield counter. With an effective area of 142 cm(2) at 20 keV and 273 cm(2) at 150 keV, the background level at sea level reached similar to 1 X 10(-5) cts s(-1) cm(-2) keV(-1) at 30 keV for the PIN diodes, and similar to 2 X 10(-5) cts s(-1) cm(-2) keV(-1) at 100 keV, and similar to 7 X 10(-6) cts s(-1) cm(-2) keV(-1) at 200 keV for the phoswich counter. Tight active shielding of the HXD results in a large array of guard counters surrounding the main detector parts. These anti-coincidence counters, made of similar to 4 cm thick BGO crystals, have a large effective area for sub-MeV to MeV gamma-rays. They work as an excellent gamma-ray burst monitor with limited angular resolution (similar to 5 degrees). The on-board signal-processing system and the data transmitted to the ground are also described.

DOI
A Suzaku observation of the low-ionization Fe-Line emission from RCW 86

Masaru Ueno, Rie Sato, Jun Kataoka, Aya Bamba, Ilana Harrus, Junko Hiraga, John P. Hughes, Caroline A. Kilbourne, Katsuji Koyama, Motohide Kokubun, Hiroshi Nakajima, Masanobu Ozaki, Robert Petre, Tadayuki Takahashi, Takaaki Tanaka, Hiroshi Tomida, Hiroya Yaniaguchi

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 59 S171 - S176 2007年01月

　概要を見る

The newly operational X-ray satellite Suzaku observed the southwestern quadrant of the supernova remnant RCW 86 in 2006 February to study the nature of the 6.4 keV emission line first detected with the Advanced Satellite for Cosmology and Astronomy (ASCA). The new data confirm the existence of the line, localizing it for the first time; most of the line emission is adjacent and interior to the forward shock, and not at the locus of the continuum hard emission. We also report the first detection of a 7.1 keV line, which we interpret as K beta emission from low-ionization iron. The Fe K line features are consistent with a non-equilibrium plasma of Fe-rich ejecta with n(e)t less than or similar to 10(9) cm(-3) s and kT(e) similar to 5 keV. This combination of low n(e)t and high kT(e) suggests collisionless electron heating in an SNR shock. The Fe K alpha line shows evidence for intrinsic broadening, with a width of 47 (34-59) eV (99% error region). The difference in the spatial distributions of the hard continuum above 3 keV and the Fe K line emission supports a synchrotron origin for the hard continuum.

DOI
Pre-flight performance and radiation hardness of the Tokyo Tech pico-satellite Cute-1.7

J. Kotoku, J. Kataoka, Y. Kuramoto, Y. Tsubuku, Y. Yatsu, R. Sato, T. Ikagawa, T. Saito, N. Kawai, K. Konoue, N. Miyashita, M. Iai, K. Omagari, M. Kashiwa, H. Yabe, K. Imai, Miyamoto, K. Fujiwara, S. Masumoto, T. Usuda, T. Iljic, A. Konda, S. Sugita, T. Yamanaka, D. Matsuura, T. Sagami, S. Kajiwara, Y. Funaki, S. Matsunaga, T. Shima, S. Kishimoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 565 ( 2 ) 677 - 685 2006年09月

　概要を見る

The Cute-1.7 was launched successfully in February 2006 as a piggyback satellite of the Astro-F mission. The Cute-1.7 dimensions are 10 x 10 x 20 cm(3) box with a total mass of 3.6kg. It is the second pico-satellite to have been developed completely by students of the Tokyo Institute of Technology (Tokyo Tech.) after the successful launch of the CUTE-I in June 2003. The goals of the Cute-1.7 mission are two-fold: (1) to validate high-performance, commercially available products for the first time in space. We particularly use personal digital assistants (PDAs) as a main computer in orbit (2) to demonstrate new potential uses for small satellites in various space studies, as proposed by the "satellite-core" concept. For the Cute-1.7 mission, we will carry avalanche photo diodes (APDs) as a high-count particle monitor in low-Earth orbit. Here we present details of various ground tests and pre-flight performance of the Cute-1.7 immediately before the launch. Results of the Cute-1.7 mission will provide quick feedback for space applications of APDs in Japan's future X-ray astronomy mission NeXT. (c) 2006 Elsevier B.V. All rights reserved.

DOI CiNii
Pre-flight performance and radiation hardness of the Tokyo Tech pico-satellite Cute-1.7

J. Kotoku, J. Kataoka, Y. Kuramoto, Y. Tsubuku, Y. Yatsu, R. Sato, T. Ikagawa, T. Saito, N. Kawai, K. Konoue, N. Miyashita, M. Iai, K. Omagari, M. Kashiwa, H. Yabe, K. Imai, Miyamoto, K. Fujiwara, S. Masumoto, T. Usuda, T. Iljic, A. Konda, S. Sugita, T. Yamanaka, D. Matsuura, T. Sagami, S. Kajiwara, Y. Funaki, S. Matsunaga, T. Shima, S. Kishimoto

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 565 ( 2 ) 677 - 685 2006年09月

　概要を見る

The Cute-1.7 was launched successfully in February 2006 as a piggyback satellite of the Astro-F mission. The Cute-1.7 dimensions are 10 x 10 x 20 cm(3) box with a total mass of 3.6kg. It is the second pico-satellite to have been developed completely by students of the Tokyo Institute of Technology (Tokyo Tech.) after the successful launch of the CUTE-I in June 2003. The goals of the Cute-1.7 mission are two-fold: (1) to validate high-performance, commercially available products for the first time in space. We particularly use personal digital assistants (PDAs) as a main computer in orbit (2) to demonstrate new potential uses for small satellites in various space studies, as proposed by the "satellite-core" concept. For the Cute-1.7 mission, we will carry avalanche photo diodes (APDs) as a high-count particle monitor in low-Earth orbit. Here we present details of various ground tests and pre-flight performance of the Cute-1.7 immediately before the launch. Results of the Cute-1.7 mission will provide quick feedback for space applications of APDs in Japan's future X-ray astronomy mission NeXT. (c) 2006 Elsevier B.V. All rights reserved.

DOI CiNii
23pSH-13 宇宙ガンマ線衛星GLASTの最終組み上げ試験と現状(23pSH X線・γ線,宇宙線・宇宙物理領)

高橋弘充, 大杉節, 深沢泰司, 水野恒史, 片桐秀明, 川端弘治, 河本卓也, 釜江常好, 田島宏康, 河合誠之, 片岡淳, 高橋忠幸, GLASTチーム

日本物理学会講演概要集 61 ( 2 ) 79 - 79 2006年08月

CiNii
An active gain-control system for avalanche photo-diodes under moderate temperature variations

J. Kataoka, R. Sato, T. Ikagawa, J. Kotoku, Y. Kuramoto, Y. Tsubuku, T. Saito, Y. Yatsu, N. Kawai, Y. Ishikawa, N. Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 564 ( 1 ) 300 - 307 2006年08月

　概要を見る

Avalanche photodiodes (APDs) are a promising light sensor for various fields of experimental physics. It has been argued, however, that variation of APD gain with temperature could be a serious problem preventing APDs from replacing traditional photomultiplier tubes (PMTs) in some applications. Here we develop an active gain-control system to keep the APD gain stable under moderate temperature variations. As a performance demonstration of the proposed system, we have tested the response of a scintillation photon detector consisting of a 5 x 5 mm 2 reverse-type APD optically coupled with a CsI(Tl) crystal. We show that the APD gain was successfully controlled under a temperature variation of Delta T = 20 degrees C, within a time-cycle of 6000 s. The best FWHM energy resolution of 6.1 +/- 0.2 % was obtained for 662 keV gamma-rays, and the energy threshold was as low as 6.5 keV, by integrating data from +20 degrees C-0 degrees C cycles. The corresponding values for -20 degrees C-0 degrees C cycles were 6.9 +/- 0.2% and 5.2 keV, respectively. These results are comparable, or only slightly worse than that obtained at a fixed temperature. Our results suggest new potential uses for APDs in various space researches and nuclear physics. As examples, we briefly introduce the NeXT and Cute-1.7 satellite missions that will carry the APDs as scientific instruments for the first time. (c) 2006 Elsevier B.V. All rights reserved.

DOI
An active gain-control system for avalanche photo-diodes under moderate temperature variations

J. Kataoka, R. Sato, T. Ikagawa, J. Kotoku, Y. Kuramoto, Y. Tsubuku, T. Saito, Y. Yatsu, N. Kawai, Y. Ishikawa, N. Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 564 ( 1 ) 300 - 307 2006年08月

　概要を見る

Avalanche photodiodes (APDs) are a promising light sensor for various fields of experimental physics. It has been argued, however, that variation of APD gain with temperature could be a serious problem preventing APDs from replacing traditional photomultiplier tubes (PMTs) in some applications. Here we develop an active gain-control system to keep the APD gain stable under moderate temperature variations. As a performance demonstration of the proposed system, we have tested the response of a scintillation photon detector consisting of a 5 x 5 mm 2 reverse-type APD optically coupled with a CsI(Tl) crystal. We show that the APD gain was successfully controlled under a temperature variation of Delta T = 20 degrees C, within a time-cycle of 6000 s. The best FWHM energy resolution of 6.1 +/- 0.2 % was obtained for 662 keV gamma-rays, and the energy threshold was as low as 6.5 keV, by integrating data from +20 degrees C-0 degrees C cycles. The corresponding values for -20 degrees C-0 degrees C cycles were 6.9 +/- 0.2% and 5.2 keV, respectively. These results are comparable, or only slightly worse than that obtained at a fixed temperature. Our results suggest new potential uses for APDs in various space researches and nuclear physics. As examples, we briefly introduce the NeXT and Cute-1.7 satellite missions that will carry the APDs as scientific instruments for the first time. (c) 2006 Elsevier B.V. All rights reserved.

DOI
Study of avalanche photodiodes for soft X-ray detection below 20 keV

Y. Yatsu, Y. Kuramoto, J. Kataoka, J. Kotoku, T. Saito, T. Ikagawa, R. Sato, N. Kawai, S. Kishimoto, K. Mori, T. Kamae, Y. Ishikawa, N. Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 564 ( 1 ) 134 - 143 2006年08月

　概要を見る

The performance of the large area reach-through avalanche photodiode (APD), manufactured by Hamamatsu Photonics, K.K. as a high resolution X-ray detector is presented. The mentioned APD has an area of 3 mm 0, a fast time response for signal carrier collection and its thick depletion layer of 130 pm shows a potential to be used as an effective X-ray absorber below 20 keV. Having a capacitance of similar to 10 pF and a low dark current of 5 nA for a gain of 15, at room temperature, this APD had demonstrated one of the best energy resolutions within this kind of devices: 6.4% (FWHM) for 5.9 keV photons with a minimum detectable energy of 0.3 keV, measured at -20 degrees C. The experiments for the timing property were made in a synchrotron beam facility using an 8 keV X-ray beam; the reached count rate was above 108 counts/s, corresponding to a very short dead time of 4.5 ns/pulse. In order to test the radiation hardness of the APD, the device was irradiated at a Ring Cyclotron Facility with a 53.5 MeV proton beam. The total dose was of 11.3 krad and no fatal damage was found in the APD, although the dark current of the APD had shown an increase of one order of magnitude. Finally, the obtained results allow us to affirm that the reach-through APD has the potential to become an excellent X-ray detector, especially in the space mission application. (c) 2006 Elsevier B.V. All rights reserved.

DOI CiNii
Dynamics and high-energy emission of the flaring HST-1 knot in the M 87 jet

L. Stawarz, F. Aharonian, J. Kataoka, M. Ostrowski, A. Siemiginowska, M. Sikora

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 370 ( 2 ) 981 - 992 2006年08月

　概要を見る

Stimulated by recent observations of a giant radio-to-X-ray synchrotron flare from Hubble Space Telescope (HST)-1, the innermost knot of the M 87 jet, as well as by the detection of a very high energy gamma-ray emission from M 87, we investigated the dynamics and multiwavelength emission of the HST-1 region. We study thermal pressure of the hot interstellar medium in M 87 and argue for the presence of a gaseous condensation in its central parts. We postulate that this additional feature is linked to the observed central stellar cusp of the elliptical host. Interaction of the jet with such a feature is likely to result in the formation of a stationary converging/diverging reconfinement/reflected shock structure in the innermost parts of the M 87 jet. We show that for a realistic set of the outflow parameters, a stationary and a flaring part of the HST-1 knot located similar to 100 pc away from the active centre can be associated with the decelerated portion of the jet matter placed immediately downstream of the point where the reconfinement shock reaches the jet axis. We discuss a possible scenario explaining a broad-band brightening of the HST-1 region related to the variable activity of the central core. In particular, we show that assuming a previous epoch of the high central black hole activity resulting in ejection of excess particles and photons down along the jet, one may first expect a high-energy flare of HST-1 due to inverse-Comptonization of the nuclear radiation, followed after a few years by an increase in the synchrotron continuum of this region. The synchrotron flare itself could be accompanied by a subsequent inverse-Compton brightening due to upscattering of the ambient (mostly starlight) photons. If this is the case, then the recently observed order-of-magnitude increase in the knot luminosity in all spectral bands could be regarded as an unusual echo of the order-of-magnitude outburst that had happened previously (and could be eventually observed some similar to 40 yr ago) in the highly relativistic active core of the M 87 radio galaxy. We show that very high energy gamma-ray fluxes expected in a framework of the proposed scenario are consistent with the observed ones.

DOI
An active gain-control system for avalanche photo-diodes under moderate temperature variations

J. Kataoka, R. Sato, T. Ikagawa, J. Kotoku, Y. Kuramoto, Y. Tsubuku, T. Saito, Y. Yatsu, N. Kawai, Y. Ishikawa, N. Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 564 ( 1 ) 300 - 307 2006年08月

　概要を見る

Avalanche photodiodes (APDs) are a promising light sensor for various fields of experimental physics. It has been argued, however, that variation of APD gain with temperature could be a serious problem preventing APDs from replacing traditional photomultiplier tubes (PMTs) in some applications. Here we develop an active gain-control system to keep the APD gain stable under moderate temperature variations. As a performance demonstration of the proposed system, we have tested the response of a scintillation photon detector consisting of a 5 x 5 mm 2 reverse-type APD optically coupled with a CsI(Tl) crystal. We show that the APD gain was successfully controlled under a temperature variation of Delta T = 20 degrees C, within a time-cycle of 6000 s. The best FWHM energy resolution of 6.1 +/- 0.2 % was obtained for 662 keV gamma-rays, and the energy threshold was as low as 6.5 keV, by integrating data from +20 degrees C-0 degrees C cycles. The corresponding values for -20 degrees C-0 degrees C cycles were 6.9 +/- 0.2% and 5.2 keV, respectively. These results are comparable, or only slightly worse than that obtained at a fixed temperature. Our results suggest new potential uses for APDs in various space researches and nuclear physics. As examples, we briefly introduce the NeXT and Cute-1.7 satellite missions that will carry the APDs as scientific instruments for the first time. (c) 2006 Elsevier B.V. All rights reserved.

DOI CiNii
Study of avalanche photodiodes for soft X-ray detection below 20 keV

Y. Yatsu, Y. Kuramoto, J. Kataoka, J. Kotoku, T. Saito, T. Ikagawa, R. Sato, N. Kawai, S. Kishimoto, K. Mori, T. Kamae, Y. Ishikawa, N. Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 564 ( 1 ) 134 - 143 2006年08月

　概要を見る

The performance of the large area reach-through avalanche photodiode (APD), manufactured by Hamamatsu Photonics, K.K. as a high resolution X-ray detector is presented. The mentioned APD has an area of 3 mm 0, a fast time response for signal carrier collection and its thick depletion layer of 130 pm shows a potential to be used as an effective X-ray absorber below 20 keV. Having a capacitance of similar to 10 pF and a low dark current of 5 nA for a gain of 15, at room temperature, this APD had demonstrated one of the best energy resolutions within this kind of devices: 6.4% (FWHM) for 5.9 keV photons with a minimum detectable energy of 0.3 keV, measured at -20 degrees C. The experiments for the timing property were made in a synchrotron beam facility using an 8 keV X-ray beam; the reached count rate was above 108 counts/s, corresponding to a very short dead time of 4.5 ns/pulse. In order to test the radiation hardness of the APD, the device was irradiated at a Ring Cyclotron Facility with a 53.5 MeV proton beam. The total dose was of 11.3 krad and no fatal damage was found in the APD, although the dark current of the APD had shown an increase of one order of magnitude. Finally, the obtained results allow us to affirm that the reach-through APD has the potential to become an excellent X-ray detector, especially in the space mission application. (c) 2006 Elsevier B.V. All rights reserved.

DOI CiNii
Dynamics and high-energy emission of the flaring HST-1 knot in the M 87 jet

L. Stawarz, F. Aharonian, J. Kataoka, M. Ostrowski, A. Siemiginowska, M. Sikora

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 370 ( 2 ) 981 - 992 2006年08月

　概要を見る

Stimulated by recent observations of a giant radio-to-X-ray synchrotron flare from Hubble Space Telescope (HST)-1, the innermost knot of the M 87 jet, as well as by the detection of a very high energy gamma-ray emission from M 87, we investigated the dynamics and multiwavelength emission of the HST-1 region. We study thermal pressure of the hot interstellar medium in M 87 and argue for the presence of a gaseous condensation in its central parts. We postulate that this additional feature is linked to the observed central stellar cusp of the elliptical host. Interaction of the jet with such a feature is likely to result in the formation of a stationary converging/diverging reconfinement/reflected shock structure in the innermost parts of the M 87 jet. We show that for a realistic set of the outflow parameters, a stationary and a flaring part of the HST-1 knot located similar to 100 pc away from the active centre can be associated with the decelerated portion of the jet matter placed immediately downstream of the point where the reconfinement shock reaches the jet axis. We discuss a possible scenario explaining a broad-band brightening of the HST-1 region related to the variable activity of the central core. In particular, we show that assuming a previous epoch of the high central black hole activity resulting in ejection of excess particles and photons down along the jet, one may first expect a high-energy flare of HST-1 due to inverse-Comptonization of the nuclear radiation, followed after a few years by an increase in the synchrotron continuum of this region. The synchrotron flare itself could be accompanied by a subsequent inverse-Compton brightening due to upscattering of the ambient (mostly starlight) photons. If this is the case, then the recently observed order-of-magnitude increase in the knot luminosity in all spectral bands could be regarded as an unusual echo of the order-of-magnitude outburst that had happened previously (and could be eventually observed some similar to 40 yr ago) in the highly relativistic active core of the M 87 radio galaxy. We show that very high energy gamma-ray fluxes expected in a framework of the proposed scenario are consistent with the observed ones.

DOI
An active gain-control system for avalanche photo-diodes under moderate temperature variations

J. Kataoka, R. Sato, T. Ikagawa, J. Kotoku, Y. Kuramoto, Y. Tsubuku, T. Saito, Y. Yatsu, N. Kawai, Y. Ishikawa, N. Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 564 ( 1 ) 300 - 307 2006年08月

　概要を見る

Avalanche photodiodes (APDs) are a promising light sensor for various fields of experimental physics. It has been argued, however, that variation of APD gain with temperature could be a serious problem preventing APDs from replacing traditional photomultiplier tubes (PMTs) in some applications. Here we develop an active gain-control system to keep the APD gain stable under moderate temperature variations. As a performance demonstration of the proposed system, we have tested the response of a scintillation photon detector consisting of a 5 x 5 mm 2 reverse-type APD optically coupled with a CsI(Tl) crystal. We show that the APD gain was successfully controlled under a temperature variation of Delta T = 20 degrees C, within a time-cycle of 6000 s. The best FWHM energy resolution of 6.1 +/- 0.2 % was obtained for 662 keV gamma-rays, and the energy threshold was as low as 6.5 keV, by integrating data from +20 degrees C-0 degrees C cycles. The corresponding values for -20 degrees C-0 degrees C cycles were 6.9 +/- 0.2% and 5.2 keV, respectively. These results are comparable, or only slightly worse than that obtained at a fixed temperature. Our results suggest new potential uses for APDs in various space researches and nuclear physics. As examples, we briefly introduce the NeXT and Cute-1.7 satellite missions that will carry the APDs as scientific instruments for the first time. (c) 2006 Elsevier B.V. All rights reserved.

DOI CiNii
The spectral energy distribution of PKS 2004-447: a compact steep-spectrum source and possible radio-loud narrow-line Seyfert 1 galaxy

L. C. Gallo, P. G. Edwards, E. Ferrero, J. Kataoka, D. R. Lewis, S. P. Ellingsen, Z. Misanovic, W. F. Welsh, M. Whiting, Th. Boller, W. Brinkmann, J. Greenhill, A. Oshlack

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 370 ( 1 ) 245 - 254 2006年07月

　概要を見る

An investigation of the spectral energy distribution ( SED) of the compact steep-spectrum (CSS) source and possible radio-loud narrow-line Seyfert 1 galaxy (NLS1), PKS 2004-447, is presented. Five out of six well-studied radio-loud NLS1 share this dual classification [optically defined as an NLS1 with radio definition of a CSS or gigahertz-peaked spectrum (GPS) source], suggesting that the connection could have a physical origin. The SED is created from simultaneous observations (within 24 h) at radio (from Australia Telescope Compact Array), optical/near-infrared (NIR) (from Siding Spring) and UV/X-ray (from XMM-Newton) wave-lengths. The X-ray data show evidence of short-term variability (primarily a similar to 30 per cent increase in the final 4 ks of the observation), a possible soft excess and negligible absorption. Together with the rest of the SED, the X-ray emission is excessive in comparison to synchrotron plus synchrotron self-Compton (SSC) models. The SED can be described with a two-component model consisting of extended synchrotron/SSC emission with Comptonization in the X-rays, though SSC models with a very high electron-to-magnetic energy density ratio cannot be excluded either. The peak emission in the SED appears to be in the NIR, which can be attributed to thermal emission (T approximate to 1000 K) from a dusty torus. Analysis of a. non-contemporaneous, low-resolution optical spectrum suggests that the narrow-line region (NLR) is much more reddened than the X-ray emitting region suggesting that the gas-to-dust ratio in PKS 2004-447 may be very different than in our own Galaxy. This could be achieved if the radio jets in PKS 2004-447 deposits material from the nucleus into the NLR. Long-term radio monitoring of PKS 2004-447 shows a rather constant light curve over nearly a six-month period with the exception of one outburst when the 6.65-GHz flux increased by similar to 35 per cent over 19 d. It is not possible to differentiate between intrinsic or extrinsic (i.e. interstellar scintillation) origins for this outburst, but the detection of the rare event demonstrates the importance of intensive monitoring campaigns. In comparison to general samples of GPS sources, which appear to be X-ray weak, NLS1-CSS/GPS sources possess stronger X-ray emission relative to radio ( comparable to normal radio-loud AGN). In addition, NLS1-CSS/GPS sources also exhibit lower intrinsic absorption than GPS sources of similar X-ray luminosity. This is consistent with the additional X-ray component required for PKS 2004-447, but larger samples of NLS1-CSS/GPS are needed before any conclusive remarks can be made.

DOI
The spectral energy distribution of PKS 2004-447: a compact steep-spectrum source and possible radio-loud narrow-line Seyfert 1 galaxy

L. C. Gallo, P. G. Edwards, E. Ferrero, J. Kataoka, D. R. Lewis, S. P. Ellingsen, Z. Misanovic, W. F. Welsh, M. Whiting, Th. Boller, W. Brinkmann, J. Greenhill, A. Oshlack

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 370 ( 1 ) 245 - 254 2006年07月

　概要を見る

An investigation of the spectral energy distribution ( SED) of the compact steep-spectrum (CSS) source and possible radio-loud narrow-line Seyfert 1 galaxy (NLS1), PKS 2004-447, is presented. Five out of six well-studied radio-loud NLS1 share this dual classification [optically defined as an NLS1 with radio definition of a CSS or gigahertz-peaked spectrum (GPS) source], suggesting that the connection could have a physical origin. The SED is created from simultaneous observations (within 24 h) at radio (from Australia Telescope Compact Array), optical/near-infrared (NIR) (from Siding Spring) and UV/X-ray (from XMM-Newton) wave-lengths. The X-ray data show evidence of short-term variability (primarily a similar to 30 per cent increase in the final 4 ks of the observation), a possible soft excess and negligible absorption. Together with the rest of the SED, the X-ray emission is excessive in comparison to synchrotron plus synchrotron self-Compton (SSC) models. The SED can be described with a two-component model consisting of extended synchrotron/SSC emission with Comptonization in the X-rays, though SSC models with a very high electron-to-magnetic energy density ratio cannot be excluded either. The peak emission in the SED appears to be in the NIR, which can be attributed to thermal emission (T approximate to 1000 K) from a dusty torus. Analysis of a. non-contemporaneous, low-resolution optical spectrum suggests that the narrow-line region (NLR) is much more reddened than the X-ray emitting region suggesting that the gas-to-dust ratio in PKS 2004-447 may be very different than in our own Galaxy. This could be achieved if the radio jets in PKS 2004-447 deposits material from the nucleus into the NLR. Long-term radio monitoring of PKS 2004-447 shows a rather constant light curve over nearly a six-month period with the exception of one outburst when the 6.65-GHz flux increased by similar to 35 per cent over 19 d. It is not possible to differentiate between intrinsic or extrinsic (i.e. interstellar scintillation) origins for this outburst, but the detection of the rare event demonstrates the importance of intensive monitoring campaigns. In comparison to general samples of GPS sources, which appear to be X-ray weak, NLS1-CSS/GPS sources possess stronger X-ray emission relative to radio ( comparable to normal radio-loud AGN). In addition, NLS1-CSS/GPS sources also exhibit lower intrinsic absorption than GPS sources of similar X-ray luminosity. This is consistent with the additional X-ray component required for PKS 2004-447, but larger samples of NLS1-CSS/GPS are needed before any conclusive remarks can be made.

DOI
The X-ray jet in Centaurus A: Clues to the jet structure and particle acceleration

J Kataoka, L Stawarz, F Aharonian, F Takahara, M Ostrowski, PG Edwards

ASTROPHYSICAL JOURNAL 641 ( 1 ) 158 - 168 2006年04月

　概要を見る

We report detailed studies of the X-ray emission from the kiloparsec-scale jet in the nearest active galaxy, Centaurus A. By analyzing the highest quality X-ray data obtained with the Chandra ACIS-S, 41 compact sources (mostly bright jet knots) were found within the jet on angular scales less than 400, 13 of which were newly identified. We construct the luminosity function for the detected jet knots and argue that the remaining emission is most likely to be truly diffuse, rather than resulting from the sum of many unresolved fainter knots. We subtracted the contributions of the bright knots from the total X-ray jet flux, and show that the remaining extended emission has a relatively flat-topped intensity profile in the transverse jet direction, with the intensity peaking at the jet boundaries between 5000 and 17000. We note that limb-brightened morphologies have been observed previously at radio frequencies in a few FR I and FR II jet sources, but never so clearly at higher photon energies. Our result therefore supports a stratified jet model, consisting of a relativistic outflow including a boundary layer with a velocity shear. In addition, we found that the X-ray spectrum of the diffuse component is almost uniform across and along the jet, with an X-ray energy spectral index of alpha(X)approximate to 1, similar to those observed in the compact knots. We discuss this spectral behavior within a framework of shock and stochastic particle acceleration processes, connected with the turbulent, supersonic, and nonsteady nature of the relativistic outflow. We note some evidence for a possible spectral hardening at the outer sheath of the jet, and manifesting itself in observed X-ray spectra of alpha(X)< 0.5 in the most extreme cases. Due to the limited photon statistics of the present data, further deep observations of Centaurus A are required to determine the reality of this finding; however, we note that the existence of the hard X-ray features at outer jet boundaries would provide an important challenge to theories for the evolution of ultrarelativistic particles within extragalactic jets.

DOI
The X-ray jet in Centaurus A: Clues to the jet structure and particle acceleration

J Kataoka, L Stawarz, F Aharonian, F Takahara, M Ostrowski, PG Edwards

ASTROPHYSICAL JOURNAL 641 ( 1 ) 158 - 168 2006年04月

　概要を見る

We report detailed studies of the X-ray emission from the kiloparsec-scale jet in the nearest active galaxy, Centaurus A. By analyzing the highest quality X-ray data obtained with the Chandra ACIS-S, 41 compact sources (mostly bright jet knots) were found within the jet on angular scales less than 400, 13 of which were newly identified. We construct the luminosity function for the detected jet knots and argue that the remaining emission is most likely to be truly diffuse, rather than resulting from the sum of many unresolved fainter knots. We subtracted the contributions of the bright knots from the total X-ray jet flux, and show that the remaining extended emission has a relatively flat-topped intensity profile in the transverse jet direction, with the intensity peaking at the jet boundaries between 5000 and 17000. We note that limb-brightened morphologies have been observed previously at radio frequencies in a few FR I and FR II jet sources, but never so clearly at higher photon energies. Our result therefore supports a stratified jet model, consisting of a relativistic outflow including a boundary layer with a velocity shear. In addition, we found that the X-ray spectrum of the diffuse component is almost uniform across and along the jet, with an X-ray energy spectral index of alpha(X)approximate to 1, similar to those observed in the compact knots. We discuss this spectral behavior within a framework of shock and stochastic particle acceleration processes, connected with the turbulent, supersonic, and nonsteady nature of the relativistic outflow. We note some evidence for a possible spectral hardening at the outer sheath of the jet, and manifesting itself in observed X-ray spectra of alpha(X)< 0.5 in the most extreme cases. Due to the limited photon statistics of the present data, further deep observations of Centaurus A are required to determine the reality of this finding; however, we note that the existence of the hard X-ray features at outer jet boundaries would provide an important challenge to theories for the evolution of ultrarelativistic particles within extragalactic jets.

DOI
The X-ray jet in Centaurus A: Clues to the jet structure and particle acceleration

J Kataoka, L Stawarz, F Aharonian, F Takahara, M Ostrowski, PG Edwards

ASTROPHYSICAL JOURNAL 641 ( 1 ) 158 - 168 2006年04月

　概要を見る

We report detailed studies of the X-ray emission from the kiloparsec-scale jet in the nearest active galaxy, Centaurus A. By analyzing the highest quality X-ray data obtained with the Chandra ACIS-S, 41 compact sources (mostly bright jet knots) were found within the jet on angular scales less than 400, 13 of which were newly identified. We construct the luminosity function for the detected jet knots and argue that the remaining emission is most likely to be truly diffuse, rather than resulting from the sum of many unresolved fainter knots. We subtracted the contributions of the bright knots from the total X-ray jet flux, and show that the remaining extended emission has a relatively flat-topped intensity profile in the transverse jet direction, with the intensity peaking at the jet boundaries between 5000 and 17000. We note that limb-brightened morphologies have been observed previously at radio frequencies in a few FR I and FR II jet sources, but never so clearly at higher photon energies. Our result therefore supports a stratified jet model, consisting of a relativistic outflow including a boundary layer with a velocity shear. In addition, we found that the X-ray spectrum of the diffuse component is almost uniform across and along the jet, with an X-ray energy spectral index of alpha(X)approximate to 1, similar to those observed in the compact knots. We discuss this spectral behavior within a framework of shock and stochastic particle acceleration processes, connected with the turbulent, supersonic, and nonsteady nature of the relativistic outflow. We note some evidence for a possible spectral hardening at the outer sheath of the jet, and manifesting itself in observed X-ray spectra of alpha(X)< 0.5 in the most extreme cases. Due to the limited photon statistics of the present data, further deep observations of Centaurus A are required to determine the reality of this finding; however, we note that the existence of the hard X-ray features at outer jet boundaries would provide an important challenge to theories for the evolution of ultrarelativistic particles within extragalactic jets.

DOI
The parsec-scale jet of PKS 0637-752

Philip G. Edwards, B. Glenn Piner, Steven J. Tingay, James E. J. Lovell, Jun Kataoka, Roopesh Ojha, Yasuhiro Murata

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 58 ( 2 ) 233 - 241 2006年04月

　概要を見る

Chandra observations of the quasar PKS 0637-752 during its checkout phase resulted in the unexpected detection of a luminous kiloparsec-scale X-ray jet. The apparent superluminal speed of this jet on the parsec-scale, based on two VSOP and four ground-based observations, has proven crucial to understanding the X-ray production in the arcsec-scale jet. We present here for the first time the full details of the ground-based observations used to determine the parsec-scale jet speed, describe the results of a third VSOP observation, and examine the reported jet speed in the light of more recent ground-based VLBI observations. We find some evidence of increased source activity coincident with extrapolated epochs of jet component ejection, although the monitoring of the source is relatively sparse and the ejection epochs are not tightly constrained. We also construct the spectral energy distribution for the nucleus of PKS 0637-752 and show that it can be modelled well in terms of a one-zone synchrotron self-Compton model of an electron-positron jet with a Doppler factor of similar to 10, consistent with the results of the VLBI observations.

DOI
The X-ray jet in Centaurus A: Clues to the jet structure and particle acceleration

J Kataoka, L Stawarz, F Aharonian, F Takahara, M Ostrowski, PG Edwards

ASTROPHYSICAL JOURNAL 641 ( 1 ) 158 - 168 2006年04月

　概要を見る

We report detailed studies of the X-ray emission from the kiloparsec-scale jet in the nearest active galaxy, Centaurus A. By analyzing the highest quality X-ray data obtained with the Chandra ACIS-S, 41 compact sources (mostly bright jet knots) were found within the jet on angular scales less than 400, 13 of which were newly identified. We construct the luminosity function for the detected jet knots and argue that the remaining emission is most likely to be truly diffuse, rather than resulting from the sum of many unresolved fainter knots. We subtracted the contributions of the bright knots from the total X-ray jet flux, and show that the remaining extended emission has a relatively flat-topped intensity profile in the transverse jet direction, with the intensity peaking at the jet boundaries between 5000 and 17000. We note that limb-brightened morphologies have been observed previously at radio frequencies in a few FR I and FR II jet sources, but never so clearly at higher photon energies. Our result therefore supports a stratified jet model, consisting of a relativistic outflow including a boundary layer with a velocity shear. In addition, we found that the X-ray spectrum of the diffuse component is almost uniform across and along the jet, with an X-ray energy spectral index of alpha(X)approximate to 1, similar to those observed in the compact knots. We discuss this spectral behavior within a framework of shock and stochastic particle acceleration processes, connected with the turbulent, supersonic, and nonsteady nature of the relativistic outflow. We note some evidence for a possible spectral hardening at the outer sheath of the jet, and manifesting itself in observed X-ray spectra of alpha(X)< 0.5 in the most extreme cases. Due to the limited photon statistics of the present data, further deep observations of Centaurus A are required to determine the reality of this finding; however, we note that the existence of the hard X-ray features at outer jet boundaries would provide an important challenge to theories for the evolution of ultrarelativistic particles within extragalactic jets.

DOI
The parsec-scale jet of PKS 0637-752

Philip G. Edwards, B. Glenn Piner, Steven J. Tingay, James E. J. Lovell, Jun Kataoka, Roopesh Ojha, Yasuhiro Murata

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 58 ( 2 ) 233 - 241 2006年04月

　概要を見る

Chandra observations of the quasar PKS 0637-752 during its checkout phase resulted in the unexpected detection of a luminous kiloparsec-scale X-ray jet. The apparent superluminal speed of this jet on the parsec-scale, based on two VSOP and four ground-based observations, has proven crucial to understanding the X-ray production in the arcsec-scale jet. We present here for the first time the full details of the ground-based observations used to determine the parsec-scale jet speed, describe the results of a third VSOP observation, and examine the reported jet speed in the light of more recent ground-based VLBI observations. We find some evidence of increased source activity coincident with extrapolated epochs of jet component ejection, although the monitoring of the source is relatively sparse and the ejection epochs are not tightly constrained. We also construct the spectral energy distribution for the nucleus of PKS 0637-752 and show that it can be modelled well in terms of a one-zone synchrotron self-Compton model of an electron-positron jet with a Doppler factor of similar to 10, consistent with the results of the VLBI observations.

DOI
30aSD-2 大学小型衛星Cute-1.7によるAPDの宇宙動作実証(30aSD X線・γ線,宇宙線・宇宙物理領域)

古徳純一, 片岡淳, 河合誠之, 倉本祐介, 谷津陽一, 津布久佳宏, および工学部松永研究室

日本物理学会講演概要集 61 ( 1 ) 103 - 103 2006年03月

CiNii
28pTF-5 天体硬X線偏光計PoGOの開発(II)(28pTF X線・γ線,宇宙線・宇宙物理領域)

植野優, 金井義和, 有元誠, 片岡淳, 河合誠之, 水野恒史, 山本和英, 深沢泰司, Ylinen Tomi P., Kiss Mozsi, 釜江常好, 田島宏康, Apte Zachary, 郡司修一, 高橋忠幸, 斉藤芳隆

日本物理学会講演概要集 61 ( 1 ) 97 - 97 2006年03月

CiNii
明野ガンマ線バースト観測用50cm望遠鏡の開発

下川辺隆史, 河合誠之, 片岡淳, 小谷太郎, 佐藤理江, 谷津陽一, 有元誠, 渡部潤一, 福島英雄, 柳澤顕史, 清水康広, 吉田道利, 長山省吾, 太田耕司, 吉田篤正, 黒田大介, 戸田博之

日本天文学会年会講演予稿集 2006 214 2006年02月

J-GLOBAL
すざく衛星によるTeV γ線天体HESS J1616‐508の観測

松本浩典, 片桐秀明, 鶴剛, 小山勝二, 馬場彩, 千田篤史, 平賀純子, 高橋忠幸, 植野優, 片岡淳

日本天文学会年会講演予稿集 2006 148 2006年02月

J-GLOBAL
すざく衛星による超新星残骸RX J1713.7‐3946の観測

田中孝明, 高橋忠幸, 中澤知洋, 平賀純子, 渡辺伸, 馬場彩, 高橋弘充, 片岡淳

日本天文学会年会講演予稿集 2006 149 2006年02月

J-GLOBAL
「三つ目」望遠鏡の3色同時撮像カメラの更新

長山省吾, 柳澤顕史, 沖田喜一, 清水康広, 吉田道利, 河合誠之, 戸田博之, 小谷太郎, 片岡淳, 佐藤理江, 鈴木素子, 谷津陽一, 有元誠, 下河辺隆史, 太田耕司, 渡部潤一, 黒田大介, 吉田篤正

日本天文学会年会講演予稿集 2006 215 2006年02月

J-GLOBAL
Kiloparsec-scale jets in FR I radio galaxies and the gamma-ray background

L Stawarz, TM Kneiske, J Kataoka

ASTROPHYSICAL JOURNAL 637 ( 2 ) 693 - 698 2006年02月

　概要を見る

We discuss the contribution of kiloparsec- scale jets in FR I radio galaxies to the diffuse gamma- ray background radiation. The analyzed gamma- ray emission comes from inverse- Compton scattering of starlight photon fields by the ultrarelativistic electrons whose synchrotron radiation is detected from such sources at radio, optical, and X- ray energies. We find that these objects, under the minimum- power hypothesis ( corresponding to a magnetic field of 300 mu G in the brightest knots of these jets), can contribute about one percent to the extragalactic gamma- ray background measured by EGRET. We point out that this result already indicates that the magnetic fields in kiloparsec- scale jets of low- power radio galaxies are not likely to be smaller than 10 mu G on average, as otherwise the extragalactic gamma- ray background would be overproduced.

DOI
Kiloparsec-scale jets in FR I radio galaxies and the gamma-ray background

L Stawarz, TM Kneiske, J Kataoka

ASTROPHYSICAL JOURNAL 637 ( 2 ) 693 - 698 2006年02月

　概要を見る

We discuss the contribution of kiloparsec- scale jets in FR I radio galaxies to the diffuse gamma- ray background radiation. The analyzed gamma- ray emission comes from inverse- Compton scattering of starlight photon fields by the ultrarelativistic electrons whose synchrotron radiation is detected from such sources at radio, optical, and X- ray energies. We find that these objects, under the minimum- power hypothesis ( corresponding to a magnetic field of 300 mu G in the brightest knots of these jets), can contribute about one percent to the extragalactic gamma- ray background measured by EGRET. We point out that this result already indicates that the magnetic fields in kiloparsec- scale jets of low- power radio galaxies are not likely to be smaller than 10 mu G on average, as otherwise the extragalactic gamma- ray background would be overproduced.

DOI
Cute-1.7搭載APDモジュールの放射線耐性と性能評価

津布久佳宏, 谷津陽一, 古徳純一, 片岡淳, 河合誠之, 尾曲邦之, 根田康実, 芦田宏樹

日本天文学会年会講演予稿集 2006 2006年

J-GLOBAL
27pTF-7 ガンマ線バースト残光観測望遠鏡「三つ目」の開発(27pTF 高エネルギーガンマ線・ニュートリノ,宇宙線・宇宙物理領域)

谷津陽一, 黒田大介, 戸田博之, 吉田道利, 太田耕司, 渡辺潤一, 吉田篤正, 清水康広, 沖田喜一, 下川辺隆史, 河合誠之, 小谷太郎, 片岡淳, 佐藤理江, 有元誠, 柳澤顕史, 長山省吾

日本物理学会講演概要集 61 ( 0 ) 2006年

CiNii
超小型衛星Cute1.7+APD 搭載のAPD センサー技術

片岡淳

OplusE 特集 ~宇宙における光学~ 10月号 ( vol.28 ) 1037 2006年
Suzaku observations of iron lines and reflection in AGN

J. N. Reeves, A. C. Fabian, J. Kataoka, H. Kunieda, A. Markowitz, G. Miniutti, T. Okajima, P. Serlemitsos, T. Takahashi, Y. Terashima, T. Yaqoob

ASTRONOMISCHE NACHRICHTEN 327 ( 10 ) 1079 - 1086 2006年

　概要を見る

Initial results on the iron K-shell line and reflection component in several AGN observed as part of the Suzaku Guaranteed Time program are reviewed. This paper discusses a small sample of Compton-thin Seyferts observed to date with Suzaku; namely MCG-5-23-16, MCG-6-30-15, NGC4051, NGC3516, NGC2110, 3C120 and NGC2992. The broad iron K alpha emission line appears to be present in all but one of these Seyfert galaxies, while the narrow core of the line from distant matter is ubiquitous in all the observations. The iron line in MCG-6-30-15 shows the most extreme relativistic blurring of all the objects, the red-wing of the line requires the inner accretion disk to extend inwards to within 2.2R(g) of the black hole, in agreement with the XMM-Newton observations. Strong excess emission in the Hard X-ray Detector (HXD) above 10 keV is observed in many of these Seyfert galaxies, consistent with the presence of a reflection component from reprocessing in Compton-thick matter (e.g. the accretion disk). Only one Seyfert galaxy (NGC 2110) shows neither a broad iron line nor a reflection component. The spectral variability of MCG-6-30-15, MCG-5-23-16 and NGC 4051 is also discussed. In all 3 cases, the spectra appear harder when the source is fainter, while there is little variability of the iron line or reflection component with source flux. This agrees with a simple two component spectral model, whereby the variable emission is the primary power-law, while the iron line and reflection component remain relatively constant. (c) 2006 WILEY-VCH Verlag GmbH&Co. KGaA, Weinheim.

DOI
Development of 2cm-square Hamamatsu avalanche photodiodes for high-resolution X-rays and gamma-rays detection

R Sato, J Kataoka, Y Kanai, Y Ishikawa, N Kawabata, T Ikagawa, T Saito, Y Kuramoto, N Kawai

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 556 ( 2 ) 535 - 542 2006年01月

　概要を見る

The avalanche photodiodes (APDs) have attracted considerable attention in various field of experimental physics, but their uses are still limited in only a few experiments, possibly due to their small surface areas. Here, we report the development of the large-area (similar to 20 mm square) APDs, for future applications to high-resolution X-rays and gamma-rays detection. We have made two prototypes of reverse-type APDs based on different concepts, one consists of a 2 x 2 array of 10 x 10 mm(2) pixels (APD1) and the other is a monolithic pixel of 19 x 19mm(2) size (APD2) to achieve a large effective area. By comparing the dark current and gain characteristics at room temperature (+20 degrees C) and lightly cooled environment (-20 degrees C), we quantitatively discussed the origin of predominant noise source at different temperatures. As a performance demonstration of newly developed APDs. we made a scintillation gamma-ray detector consisting of a 20 x 20 x 5mm(3) CsI(Tl) crystal and a 2cm-square APD. The best FWHM energy resolution of 8.5 +/- 0.2% were obtained for 662 keV gamma-rays at room temperature. Similarly, the best FWHM energy resolution of 8.5 0.2% were obtained for 122 keV gamma-rays at lightly cooled environment. We showed that the minimum detectable energy for scintillation light was 15 keV at 20 degrees C and less than 5 keV at -20 degrees C. (c) 2005 Elsevier B.V. All rights reserved.

DOI CiNii
Suzaku observations of iron lines and reflection in AGN

J. N. Reeves, A. C. Fabian, J. Kataoka, H. Kunieda, A. Markowitz, G. Miniutti, T. Okajima, P. Serlemitsos, T. Takahashi, Y. Terashima, T. Yaqoob

ASTRONOMISCHE NACHRICHTEN 327 ( 10 ) 1079 - 1086 2006年

　概要を見る

Initial results on the iron K-shell line and reflection component in several AGN observed as part of the Suzaku Guaranteed Time program are reviewed. This paper discusses a small sample of Compton-thin Seyferts observed to date with Suzaku; namely MCG-5-23-16, MCG-6-30-15, NGC4051, NGC3516, NGC2110, 3C120 and NGC2992. The broad iron K alpha emission line appears to be present in all but one of these Seyfert galaxies, while the narrow core of the line from distant matter is ubiquitous in all the observations. The iron line in MCG-6-30-15 shows the most extreme relativistic blurring of all the objects, the red-wing of the line requires the inner accretion disk to extend inwards to within 2.2R(g) of the black hole, in agreement with the XMM-Newton observations. Strong excess emission in the Hard X-ray Detector (HXD) above 10 keV is observed in many of these Seyfert galaxies, consistent with the presence of a reflection component from reprocessing in Compton-thick matter (e.g. the accretion disk). Only one Seyfert galaxy (NGC 2110) shows neither a broad iron line nor a reflection component. The spectral variability of MCG-6-30-15, MCG-5-23-16 and NGC 4051 is also discussed. In all 3 cases, the spectra appear harder when the source is fainter, while there is little variability of the iron line or reflection component with source flux. This agrees with a simple two component spectral model, whereby the variable emission is the primary power-law, while the iron line and reflection component remain relatively constant. (c) 2006 WILEY-VCH Verlag GmbH&Co. KGaA, Weinheim.

DOI
Development of 2cm-square Hamamatsu avalanche photodiodes for high-resolution X-rays and gamma-rays detection

R Sato, J Kataoka, Y Kanai, Y Ishikawa, N Kawabata, T Ikagawa, T Saito, Y Kuramoto, N Kawai

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 556 ( 2 ) 535 - 542 2006年01月

　概要を見る

The avalanche photodiodes (APDs) have attracted considerable attention in various field of experimental physics, but their uses are still limited in only a few experiments, possibly due to their small surface areas. Here, we report the development of the large-area (similar to 20 mm square) APDs, for future applications to high-resolution X-rays and gamma-rays detection. We have made two prototypes of reverse-type APDs based on different concepts, one consists of a 2 x 2 array of 10 x 10 mm(2) pixels (APD1) and the other is a monolithic pixel of 19 x 19mm(2) size (APD2) to achieve a large effective area. By comparing the dark current and gain characteristics at room temperature (+20 degrees C) and lightly cooled environment (-20 degrees C), we quantitatively discussed the origin of predominant noise source at different temperatures. As a performance demonstration of newly developed APDs. we made a scintillation gamma-ray detector consisting of a 20 x 20 x 5mm(3) CsI(Tl) crystal and a 2cm-square APD. The best FWHM energy resolution of 8.5 +/- 0.2% were obtained for 662 keV gamma-rays at room temperature. Similarly, the best FWHM energy resolution of 8.5 0.2% were obtained for 122 keV gamma-rays at lightly cooled environment. We showed that the minimum detectable energy for scintillation light was 15 keV at 20 degrees C and less than 5 keV at -20 degrees C. (c) 2005 Elsevier B.V. All rights reserved.

DOI CiNii
Design and performance of the soft gamma-ray detector for the NeXT mission

H Tajima, T Kamae, G Madejski, Mitani, I, K Nakazawa, T Tanaka, T Takahashi, S Watanabe, Y Fukazawa, T Ikagawa, J Kataoka, M Kokubun, K Makishima, Y Terada, M Nomachi, M Tashiro

IEEE TRANSACTIONS ON NUCLEAR SCIENCE 52 ( 6 ) 2749 - 2757 2005年12月

　概要を見る

The soft gamma-ray detector (SGD) onboard the Japanese future high energy astrophysics mission (NeXT) is a Compton telescope with narrow field of view, which utilizes Compton kinematics to enhance its background rejection capabilities. It is realized as a hybrid semiconductor gamma-ray detector which consists of silicon and cadmium telluride (CdTe) detectors. It can detect photons in a wide energy band (0.05-1 MeV) at a background level of 5 x 10(-7) counts/s/cm(2) /keV; the silicon layers are required to improve the performance at a lower energy band (< 0.3 MeV). Excellent energy resolution is the key feature of the SGD, allowing it to achieve both high angular resolution and good background rejection capability. An additional capability of the SGD, its ability to measure gamma-ray polarization, opens up a new window to study properties of astronomical objects. We will present the development of key technologies to realize the SGD: high quality CdTe, low noise front-end application-specific integrated circuit, and bump bonding technology. Energy resolutions of 1.7 keV (full-width at half-maximum) for CdTe pixel detectors and 1.1 keV for Si strip detectors have been measured. We also present the validation of Monte Carlo simulation used to evaluate the performance of the SGD.

DOI CiNii
Design and performance of the soft gamma-ray detector for the NeXT mission

H Tajima, T Kamae, G Madejski, Mitani, I, K Nakazawa, T Tanaka, T Takahashi, S Watanabe, Y Fukazawa, T Ikagawa, J Kataoka, M Kokubun, K Makishima, Y Terada, M Nomachi, M Tashiro

IEEE TRANSACTIONS ON NUCLEAR SCIENCE 52 ( 6 ) 2749 - 2757 2005年12月

　概要を見る

The soft gamma-ray detector (SGD) onboard the Japanese future high energy astrophysics mission (NeXT) is a Compton telescope with narrow field of view, which utilizes Compton kinematics to enhance its background rejection capabilities. It is realized as a hybrid semiconductor gamma-ray detector which consists of silicon and cadmium telluride (CdTe) detectors. It can detect photons in a wide energy band (0.05-1 MeV) at a background level of 5 x 10(-7) counts/s/cm(2) /keV; the silicon layers are required to improve the performance at a lower energy band (< 0.3 MeV). Excellent energy resolution is the key feature of the SGD, allowing it to achieve both high angular resolution and good background rejection capability. An additional capability of the SGD, its ability to measure gamma-ray polarization, opens up a new window to study properties of astronomical objects. We will present the development of key technologies to realize the SGD: high quality CdTe, low noise front-end application-specific integrated circuit, and bump bonding technology. Energy resolutions of 1.7 keV (full-width at half-maximum) for CdTe pixel detectors and 1.1 keV for Si strip detectors have been measured. We also present the validation of Monte Carlo simulation used to evaluate the performance of the SGD.

DOI CiNii
Chandra observation of the interaction between the hot plasma nebula RCW 89 and the pulsar jet of PSR B1509-58

Y. Yatsu, N. Kawai, J. Kataoka, T. Kotani, K. Tamura, W. Brinkmann

Astrophysical Journal 631 ( 1 I ) 312 - 319 2005年09月

　概要を見る

We present a Chandra observation of the H II region RCW 89. The nebula lies 10′ north from the central pulsar PSR B1509-58, and it has been suggested that the nebula is irradiated by the pulsar jet. We performed a spectral analysis of the seven brightest emitting regions aligned in a "horseshoe" shape and found that the temperature of the knots increases along the horseshoe in the clockwise direction, while, in contrast, the ionization parameter net decreases. This strongly supports a picture of energy transfer via the precessing pulsar jet. We examined the energy budget assuming that RCW 89 is powered by the pulsar jet and confirmed that the pulsar rotational energy loss is sufficient to drive the nebula. The rate of energy injection into RCW 89 by the jet was estimated from the synchrotron radiation flux. We obtained a heating timescale of 1400 yr, which is consistent with the pulsar characteristic age of 1700 yr. To explain the temperature gradient, we discuss the cooling process for plasma clouds in RCW 89. We argue that the plasma clouds can be cooled down by the adiabatic expansion within 70 yr and form the temperature gradient reflecting the sequential heating by the precessing pulsar jet. We also determined the velocities of the individual plasma clouds by spectral fitting. The plasma clouds in RCW 89 are moving away at 240-860 km s-1, which constrains the inclination angle of the pulsar spin axis i &gt
50° and the expanding velocity of the shell as vshell &gt
1100 km s-1. © 2005. The American Astronomical Society. All rights reserved.

DOI
Chandra observation of the interaction between the hot plasma nebula RCW 89 and the pulsar jet of PSR B1509-58

Y Yatsu, N Kawai, J Kataoka, T Kotani, K Tamura, W Brinkmann

ASTROPHYSICAL JOURNAL 631 ( 1 ) 312 - 319 2005年09月

　概要を見る

We present a Chandra observation of the H (II) region RCW 89. The nebula lies 10' north from the central pulsar PSR B1509-58, and it has been suggested that the nebula is irradiated by the pulsar jet. We performed a spectral analysis of the seven brightest emitting regions aligned in a "horseshoe'' shape and found that the temperature of the knots increases along the horseshoe in the clockwise direction, while, in contrast, the ionization parameter net decreases. This strongly supports a picture of energy transfer via the precessing pulsar jet. We examined the energy budget assuming that RCW 89 is powered by the pulsar jet and confirmed that the pulsar rotational energy loss is sufficient to drive the nebula. The rate of energy injection into RCW 89 by the jet was estimated from the synchrotron radiation flux. We obtained a heating timescale of 1400 yr, which is consistent with the pulsar characteristic age of 1700 yr. To explain the temperature gradient, we discuss the cooling process for plasma clouds in RCW 89. We argue that the plasma clouds can be cooled down by the adiabatic expansion within 70 yr and form the temperature gradient reflecting the sequential heating by the precessing pulsar jet. We also determined the velocities of the individual plasma clouds by spectral fitting. The plasma clouds in RCW 89 are moving away at 240-860 km s(-1), which constrains the inclination angle of the pulsar spin axis i > 50 degrees and the expanding velocity of the shell as nu(shell) > 1100 km s(-1).

DOI
「三つ目」岡山50cm望遠鏡の試験観測 II

柳澤顕史, 河合誠之, 太田耕司, 清水康広, 吉田道利, 長山省吾, 沖田喜一, 岡田隆史, 黒田大介, 戸田博之, 小谷太郎, 片岡淳, 佐藤理江, 鈴木素子, 谷津陽一, 有元誠, 下河辺隆史, 渡部潤一, 吉田篤正

日本天文学会年会講演予稿集 2005 261 2005年08月

J-GLOBAL
VLSIを用いたAPD多チャンネル読み出しシステムの開発

斉藤孝男, 植野優, 片岡淳, 河合誠之, 高島健, 田中孝明, 三谷烈史, 高橋忠幸

日本天文学会年会講演予稿集 2005 323 2005年08月

J-GLOBAL
15pSA-8 宇宙ガンマ線衛星GLASTの地上較正実験(15pSA X線・γ線 : X線・衛星γ,宇宙線・宇宙物理領域)

高橋弘充, 大杉節, 深沢泰司, 水野恒史, 川端弘治, 大石理子, 河本卓也, 釜江常好, 田島宏康, 河合誠之, 片岡淳, 高橋忠幸

日本物理学会講演概要集 60 ( 2 ) 40 - 40 2005年08月

CiNii
X-ray emission properties of large-scale jets, hot spots, and lobes in active galactic nuclei

Jun Kataoka, Łukasz Stawarz

Astrophysical Journal 622 ( 2 I ) 797 - 810 2005年04月

　概要を見る

We examine a systematic comparison of jet knots, hot spots, and radio lobes recently observed with Chandra and ASCA. This report discusses the origin of their X-ray emissions and investigates the dynamics of the jets. The data were compiled at well-sampled radio (5 GHz) and X-ray (1 keV) frequencies for more than 40 radio galaxies. We examine three models for the X-ray production: synchrotron (SYN), synchrotron self-Compton (SSC), and external Compton (EC) on cosmic microwave background (CMB) photons. For the SYN sources - mostly jet knots in nearby low-luminosity radio galaxies - X-ray photons are produced by ultrarelativistic electrons with energies 10-100 TeV that must be accelerated in situ. For the other objects, conservatively classified as SSC or EC sources, a simple formulation of calculating the "expected" X-ray fluxes under an equipartition hypothesis is presented. We confirm that the observed X-ray fluxes are close to the expected ones for nonrelativistic emitting plasma velocities in the case of radio lobes and the majority of hot spots, whereas a considerable fraction of jet knots are too bright in X-rays to be explained in this way. We examine two possibilities to account for the discrepancy in a framework of the inverse Compton model: (1) the magnetic field is much smaller than the equipartition value, and (2) the jets are highly relativistic on kiloparsec and megaparsec scales. We conclude that if the inverse Compton model is the case, the X-ray-bright jet knots are most likely far from the minimum-power condition. We also briefly discuss the other possibility, namely, that the observed X-ray emission from all the jet knots is synchrotron in origin. © 2005. The American Astronomical Society. All rights reserved.

DOI
Recent progress of avalanche photodiodes in high-resoution X-rays and gamma-rays detection

J Kataoka, T Saito, Y Kuramoto, T Ikagawa, Y Yatsu, J Kotoku, M Arimoto, N Kawai, Y Ishikawa, N Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 541 ( 1-2 ) 398 - 404 2005年04月

　概要を見る

We have studied the performance of large area avalanche photodiodes (APDs) recently developed by Hamamatsu Photonics K.K, in high-resolution X-rays and gamma-rays detections. We show that reach-through APD can be an excellent soft X-ray detector operating at room temperature or moderately cooled environment. We obtain the best energy resolution ever achieved with APDs, 6.4% for 5.9 keV X-rays, and obtain the energy threshold as low as 0.5 keV measured at -20 degrees C. Thanks to its fast timing response, signal carriers in the APD device are collected within a short time interval of 1.9 ns (FWHM). This type of APDs can therefore be used as a low-energy, high-counting particle monitor onboard the forthcoming Pico-satellite Cute1.7. As a scintillation photon detector, reverse-type APDs have a good advantage of reducing the dark noise significantly. The best FWHM energy resolutions of 9.4 +/- 0.3% and 4.9 +/- 0.2% were obtained for 59.5 and 662 keV gamma-rays, respectively, as measured with a CsI(T1) crystal. Combination of APDs with various other scintillators (BGO, GSO, and YAP) also showed better results than that obtained with a photomultiplier tube (PMT). These results suggest that APD could be a promising device for replacing traditional PMT usage in some applications. In particular 2-dim, APD array, which we present in this paper, will be a promising device for a wide-band X-ray and x-ray imaging detector in future space research and nuclear medicine. (c) 2005 Elsevier B.V. All rights reserved.

DOI
Recent progress of avalanche photodiodes in high-resoution X-rays and gamma-rays detection

J Kataoka, T Saito, Y Kuramoto, T Ikagawa, Y Yatsu, J Kotoku, M Arimoto, N Kawai, Y Ishikawa, N Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 541 ( 1-2 ) 398 - 404 2005年04月

　概要を見る

We have studied the performance of large area avalanche photodiodes (APDs) recently developed by Hamamatsu Photonics K.K, in high-resolution X-rays and gamma-rays detections. We show that reach-through APD can be an excellent soft X-ray detector operating at room temperature or moderately cooled environment. We obtain the best energy resolution ever achieved with APDs, 6.4% for 5.9 keV X-rays, and obtain the energy threshold as low as 0.5 keV measured at -20 degrees C. Thanks to its fast timing response, signal carriers in the APD device are collected within a short time interval of 1.9 ns (FWHM). This type of APDs can therefore be used as a low-energy, high-counting particle monitor onboard the forthcoming Pico-satellite Cute1.7. As a scintillation photon detector, reverse-type APDs have a good advantage of reducing the dark noise significantly. The best FWHM energy resolutions of 9.4 +/- 0.3% and 4.9 +/- 0.2% were obtained for 59.5 and 662 keV gamma-rays, respectively, as measured with a CsI(T1) crystal. Combination of APDs with various other scintillators (BGO, GSO, and YAP) also showed better results than that obtained with a photomultiplier tube (PMT). These results suggest that APD could be a promising device for replacing traditional PMT usage in some applications. In particular 2-dim, APD array, which we present in this paper, will be a promising device for a wide-band X-ray and x-ray imaging detector in future space research and nuclear medicine. (c) 2005 Elsevier B.V. All rights reserved.

DOI
X-ray emission properties of large-scale jets, hot spots, and lobes in active galactic nuclei

J Kataoka, L Stawarz

ASTROPHYSICAL JOURNAL 622 ( 2 ) 797 - 810 2005年04月

　概要を見る

We examine a systematic comparison of jet knots, hot spots, and radio lobes recently observed with Chandra and ASCA. This report discusses the origin of their X-ray emissions and investigates the dynamics of the jets. The data were compiled at well-sampled radio (5 GHz) and X-ray (1 keV) frequencies for more than 40 radio galaxies. We examine three models for the X-ray production: synchrotron (SYN), synchrotron self-Compton (SSC), and external Compton (EC) on cosmic microwave background (CMB) photons. For the SYN sources-mostly jet knots in nearby low-luminosity radio galaxies-X-ray photons are produced by ultrarelativistic electrons with energies 10 100 TeV that must be accelerated in situ. For the other objects, conservatively classified as SSC or EC sources, a simple formulation of calculating the "expected'' X-ray fluxes under an equipartition hypothesis is presented. We confirm that the observed X-ray fluxes are close to the expected ones for nonrelativistic emitting plasma velocities in the case of radio lobes and the majority of hot spots, whereas a considerable fraction of jet knots are too bright in X-rays to be explained in this way. We examine two possibilities to account for the discrepancy in a framework of the inverse Compton model: ( 1) the magnetic field is much smaller than the equipartition value, and ( 2) the jets are highly relativistic on kiloparsec and megaparsec scales. We conclude that if the inverse Compton model is the case, the X-ray-bright jet knots are most likely far from the minimum-power condition. We also briefly discuss the other possibility, namely, that the observed X-ray emission from all the jet knots is synchrotron in origin.

DOI
Recent progress of avalanche photodiodes in high-resoution X-rays and gamma-rays detection

J Kataoka, T Saito, Y Kuramoto, T Ikagawa, Y Yatsu, J Kotoku, M Arimoto, N Kawai, Y Ishikawa, N Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 541 ( 1-2 ) 398 - 404 2005年04月

　概要を見る

We have studied the performance of large area avalanche photodiodes (APDs) recently developed by Hamamatsu Photonics K.K, in high-resolution X-rays and gamma-rays detections. We show that reach-through APD can be an excellent soft X-ray detector operating at room temperature or moderately cooled environment. We obtain the best energy resolution ever achieved with APDs, 6.4% for 5.9 keV X-rays, and obtain the energy threshold as low as 0.5 keV measured at -20 degrees C. Thanks to its fast timing response, signal carriers in the APD device are collected within a short time interval of 1.9 ns (FWHM). This type of APDs can therefore be used as a low-energy, high-counting particle monitor onboard the forthcoming Pico-satellite Cute1.7. As a scintillation photon detector, reverse-type APDs have a good advantage of reducing the dark noise significantly. The best FWHM energy resolutions of 9.4 +/- 0.3% and 4.9 +/- 0.2% were obtained for 59.5 and 662 keV gamma-rays, respectively, as measured with a CsI(T1) crystal. Combination of APDs with various other scintillators (BGO, GSO, and YAP) also showed better results than that obtained with a photomultiplier tube (PMT). These results suggest that APD could be a promising device for replacing traditional PMT usage in some applications. In particular 2-dim, APD array, which we present in this paper, will be a promising device for a wide-band X-ray and x-ray imaging detector in future space research and nuclear medicine. (c) 2005 Elsevier B.V. All rights reserved.

DOI
Application of CdTe for the NeXT mission

T Takahashi, K Nakazawa, S Watanabe, G Sato, T Mitani, T Tanaka, K Oonuki, K Tamura, H Tajima, T Kamae, G Madejski, M Nomachi, Y Fukazawa, K Makishima, M Kokubun, Y Terada, J Kataoka, M Tashiro

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 541 ( 1-2 ) 332 - 341 2005年04月

　概要を見る

Cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) have been regarded as promising semiconductor materials for hard X-ray and gamma-ray detection. The high-atomic number of the materials (Z(Cd) = 48, Z(Te) = 52) gives a high quantum efficiency in comparison with Si. The large band-gap energy (E-g = 1.5 eV) allows to operate the detector at room temperature. Based on recent achievements in high-resolution CdTe detectors, in the technology of ASICs and in bump-bonding, we have proposed the novel hard X-ray and gamma-ray detectors for the NeXT mission in Japan. The high-energy response of the super mirror onboard NeXT will enable us to perform the first sensitive imaging observations up to 80keV. The focal plane detector, which combines a fully depleted X-ray CCD and a pixellated CdTe detector, will provide spectra and images in the wide energy range from 0.5 to 80keV. In the soft gamma-ray band up to similar to 1 MeV, a narrow field-of-view Compton gamma-ray telescope utilizing several tens of layers of thin Si or CdTe detector will provide precise spectra with much higher sensitivity than present instruments. The continuum sensitivity will reach several x 10(-8) photons(-1) keV(-1) cm(-1) in the hard X-ray region and a few X 10(-7) photons(-1) keV(-1) cm(-2) in the soft gamma-ray region. (c) 2005 Elsevier B.V. All rights reserved.

DOI
X-ray emission properties of large-scale jets, hot spots, and lobes in active galactic nuclei

Jun Kataoka, Łukasz Stawarz

Astrophysical Journal 622 ( 2 I ) 797 - 810 2005年04月

　概要を見る

We examine a systematic comparison of jet knots, hot spots, and radio lobes recently observed with Chandra and ASCA. This report discusses the origin of their X-ray emissions and investigates the dynamics of the jets. The data were compiled at well-sampled radio (5 GHz) and X-ray (1 keV) frequencies for more than 40 radio galaxies. We examine three models for the X-ray production: synchrotron (SYN), synchrotron self-Compton (SSC), and external Compton (EC) on cosmic microwave background (CMB) photons. For the SYN sources - mostly jet knots in nearby low-luminosity radio galaxies - X-ray photons are produced by ultrarelativistic electrons with energies 10-100 TeV that must be accelerated in situ. For the other objects, conservatively classified as SSC or EC sources, a simple formulation of calculating the "expected" X-ray fluxes under an equipartition hypothesis is presented. We confirm that the observed X-ray fluxes are close to the expected ones for nonrelativistic emitting plasma velocities in the case of radio lobes and the majority of hot spots, whereas a considerable fraction of jet knots are too bright in X-rays to be explained in this way. We examine two possibilities to account for the discrepancy in a framework of the inverse Compton model: (1) the magnetic field is much smaller than the equipartition value, and (2) the jets are highly relativistic on kiloparsec and megaparsec scales. We conclude that if the inverse Compton model is the case, the X-ray-bright jet knots are most likely far from the minimum-power condition. We also briefly discuss the other possibility, namely, that the observed X-ray emission from all the jet knots is synchrotron in origin. © 2005. The American Astronomical Society. All rights reserved.

DOI
Recent progress of avalanche photodiodes in high-resoution X-rays and gamma-rays detection

J Kataoka, T Saito, Y Kuramoto, T Ikagawa, Y Yatsu, J Kotoku, M Arimoto, N Kawai, Y Ishikawa, N Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 541 ( 1-2 ) 398 - 404 2005年04月

　概要を見る

We have studied the performance of large area avalanche photodiodes (APDs) recently developed by Hamamatsu Photonics K.K, in high-resolution X-rays and gamma-rays detections. We show that reach-through APD can be an excellent soft X-ray detector operating at room temperature or moderately cooled environment. We obtain the best energy resolution ever achieved with APDs, 6.4% for 5.9 keV X-rays, and obtain the energy threshold as low as 0.5 keV measured at -20 degrees C. Thanks to its fast timing response, signal carriers in the APD device are collected within a short time interval of 1.9 ns (FWHM). This type of APDs can therefore be used as a low-energy, high-counting particle monitor onboard the forthcoming Pico-satellite Cute1.7. As a scintillation photon detector, reverse-type APDs have a good advantage of reducing the dark noise significantly. The best FWHM energy resolutions of 9.4 +/- 0.3% and 4.9 +/- 0.2% were obtained for 59.5 and 662 keV gamma-rays, respectively, as measured with a CsI(T1) crystal. Combination of APDs with various other scintillators (BGO, GSO, and YAP) also showed better results than that obtained with a photomultiplier tube (PMT). These results suggest that APD could be a promising device for replacing traditional PMT usage in some applications. In particular 2-dim, APD array, which we present in this paper, will be a promising device for a wide-band X-ray and x-ray imaging detector in future space research and nuclear medicine. (c) 2005 Elsevier B.V. All rights reserved.

DOI
Application of CdTe for the NeXT mission

Tadayuki Takahashi, Kazuhiro Nakazawa, Shin Watanabe, Goro Sato, Takefumi Mitani, Takaaki Tanaka, Kousuke Oonuki, Ken'Ichi Tamura, Hiroyasu Tajima, Tuneyoshi Kamae, Greg Madejski, Masaharu Nomachi, Yasushi Fukazawa, Kazuo Makishima, Motohide Kokubun, Yukikatsu Terada, Jun Kataoka, Makoto Tashiro

Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 541 ( 1-2 ) 332 - 341 2005年04月

　概要を見る

Cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) have been regarded as promising semiconductor materials for hard X-ray and γ-ray detection. The high-atomic number of the materials (ZCd=48,ZTe=52) gives a high quantum efficiency in comparison with Si. The large band-gap energy (Eg=1.5eV) allows to operate the detector at room temperature. Based on recent achievements in high-resolution CdTe detectors, in the technology of ASICs and in bump-bonding, we have proposed the novel hard X-ray and γ-ray detectors for the NeXT mission in Japan. The high-energy response of the super mirror onboard NeXT will enable us to perform the first sensitive imaging observations up to 80 keV. The focal plane detector, which combines a fully depleted X-ray CCD and a pixellated CdTe detector, will provide spectra and images in the wide energy range from 0.5 to 80 keV. In the soft γ-ray band up to ∼1MeV, a narrow field-of-view Compton γ-ray telescope utilizing several tens of layers of thin Si or CdTe detector will provide precise spectra with much higher sensitivity than present instruments. The continuum sensitivity will reach several ×10-8photons-1keV-1cm-2 in the hard X-ray region and a few ×10-7photons-1keV-1cm-2 in the soft γ-ray region. © 2005 Elsevier B.V. All rights reserved.

DOI
明野ガンマ線バースト観測用50cm望遠鏡の開発

谷津陽一, 河合誠之, 片岡淳, 小谷太郎, 鈴木素子, 佐藤理江, 有元誠, 下川辺隆史, 渡辺潤一, 福島英雄, 柳澤顕史, 清水康広, 吉田道利, 長山省吾, 太田耕司, 吉田篤正, 黒田大介, 戸田博之

日本天文学会年会講演予稿集 2005 224 2005年02月

J-GLOBAL
Study of large area Hamamatsu avalanche photodiode in a gamma-ray scintillation detector

T Ikagawa, J Kataoka, Y Yatsu, T Saita, Y Kuramoto, N Kawai, M Kokubun, T Kamae, Y Ishikawa, N Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 538 ( 1-3 ) 640 - 650 2005年02月

　概要を見る

We have carried out study of a large area (10 x 10 mm(2)), reverse-type avalanche photodiode (APD) recently developed by Hamamatsu photonics. It has low dark current of 3 nA at room temperature, and the gain stability was almost the same as prototypical APDs reported in our previous paper. We studied the performance as a gamma-ray detector with four scintillators, CsI(Tl), BGO, GSO(Ce), and YAP(Ce) crystals. For example we obtained the best energy resolution of 4.9 +/- 0.2 % (FWHM) for 662 keV gamma-rays, as measured with a 10 x 10 x 10 mm 3 CsI(Tl) crystal. The minimum detectable energy was as low as 10 keV at 20degreesC and 3.1 keV at -20degreesC. Thanks to its large effective area, this APD can effectively read out photons from larger size scintillators. When coupling to a 300 x 48 mm(2) BGO plate of 3 mm thickness, an FWHM energy resolution of 20.9 +/- 0.2% was obtained for 662 keV gamma-rays, with the minimum detectable energy of about 60 keV at -15degreesC. These results suggest that our prototype APD can be a promising device for various applications replacing traditional PMTs such as use in space for Japan's future X-ray astronomy mission NeXT. (C) 2004 Elsevier B.V. All rights reserved.

DOI
Study of large area Hamamatsu avalanche photodiode in a gamma-ray scintillation detector

T Ikagawa, J Kataoka, Y Yatsu, T Saita, Y Kuramoto, N Kawai, M Kokubun, T Kamae, Y Ishikawa, N Kawabata

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 538 ( 1-3 ) 640 - 650 2005年02月

　概要を見る

We have carried out study of a large area (10 x 10 mm(2)), reverse-type avalanche photodiode (APD) recently developed by Hamamatsu photonics. It has low dark current of 3 nA at room temperature, and the gain stability was almost the same as prototypical APDs reported in our previous paper. We studied the performance as a gamma-ray detector with four scintillators, CsI(Tl), BGO, GSO(Ce), and YAP(Ce) crystals. For example we obtained the best energy resolution of 4.9 +/- 0.2 % (FWHM) for 662 keV gamma-rays, as measured with a 10 x 10 x 10 mm 3 CsI(Tl) crystal. The minimum detectable energy was as low as 10 keV at 20degreesC and 3.1 keV at -20degreesC. Thanks to its large effective area, this APD can effectively read out photons from larger size scintillators. When coupling to a 300 x 48 mm(2) BGO plate of 3 mm thickness, an FWHM energy resolution of 20.9 +/- 0.2% was obtained for 662 keV gamma-rays, with the minimum detectable energy of about 60 keV at -15degreesC. These results suggest that our prototype APD can be a promising device for various applications replacing traditional PMTs such as use in space for Japan's future X-ray astronomy mission NeXT. (C) 2004 Elsevier B.V. All rights reserved.

DOI
高エネルギー天体からの硬X線偏光検出器PoGOの開発

金井義和, 片岡淳, 有元誠

宇宙科学シンポジウム 5 312 - 315 2005年01月

CiNii
ガンマ線バースト偏光X線観測用小型衛星「燕」の開発

斉藤孝男, 有元誠, 片岡淳

宇宙科学シンポジウム 5 309 - 311 2005年01月

CiNii
大学小型衛星Cute-1.7フライトモデルの開発現状

古徳純一, 倉本祐輔, 片岡淳, 谷津陽一, 津布久佳宏, 河合誠之, 斎藤孝男

日本天文学会年会講演予稿集 2005 2005年

J-GLOBAL
アバランシェ・フォトダイオードの宇宙利用と放射線耐性

五十川知子, 片岡淳, 谷津陽一, 齊藤孝男, 倉本祐輔, 古徳純一, 河合誠之, 石川嘉隆, 川端信行, 岸本俊二, 嶋達志

日本天文学会年会講演予稿集 2005 2005年

J-GLOBAL
ガンマ線バースト偏光X線観測用小型衛星「燕」の開発

斉藤孝男, 有元誠, 片岡淳, 倉本祐輔, 谷津陽一, 古徳純一, 五十川知子, 河合誠之, 今井勝俊, 宮本径, 矢部秀幸, 飯沼大, 船木勇佑, 臼田武史, 藤原謙, 桝本晋嗣, 尾曲邦之, 浅見正, 宮澤航, 松永三郎

日本天文学会年会講演予稿集 2005 2005年

J-GLOBAL
Low energy response of a prototype detector array for the PoGO astronomical hard X-ray polarimeter

J. Kataoka, M. Kanal, T. Arimoto, T. Ikagawa, M. Saito, N. Ueno, R. Kawai, P. Blandford, T. Chen, G. Kamae, T. Madejski, J. Mizuno, H. Ng, T. Tajima, L. Thurston, A. Barbier, J. Harding, S. Krizmanic, J. Hunter, R. Mitchell, E. Streitmatter, R. Groth, D. Fernholtz, Y. Marlow, T. Saito, S. Takahashi, H. Gunji, Y. Sakurai, V. Fukazawa, P. Anderson, W. Carlson, M. Klamra, M. Pearce, S. Suhonen, F. Larsson, C. I. Ryde, G. Bjornsson, S. Bogaert, Kishimoto

Proceedings of SPIE - The International Society for Optical Engineering 5898 1 - 11 2005年

　概要を見る

The Polarized Gamma-ray Observer (PoGO) is a new balloon-borne instrument designed to measure polarization from astrophysical objects in the 30-200 keV range. It is under development for the first flight anticipated in 2008. PoGO is designed to minimize the background by an improved phoswich configuration, which enables a detection of 10 % polarization in a 100 mCrab source in a 6-8 hour observation. To achieve such high sensitivity, low energy response of the detector is important because the source count rate is generally dominated by the lowest energy photons. We have developed new PMT assemblies specifically designed for PoGO to read-out weak scintillation light of one photoelectron (1 p.e.) level. A beam test of a prototype detector array was conducted at the KEK Photon Factory, Tsukuba in Japan. The experimental data confirm that PoGO can detect polarization of 80-85 % polarized beam down to 30 keV with a modulation factor 0.25 ± 0.05.

DOI
X-Ray Emission Properties of Large-Scale Jets, HotSpots, and Lobes in Active Galactic Nuclei

J.Kataoka &amp, L.Stawarz

The Astrophysical Journal 622 797 2005年

DOI
Low energy response of a prototype detector array for the PoGO astronomical hard X-ray polarimeter

J. Kataoka, M. Kanal, T. Arimoto, T. Ikagawa, M. Saito, N. Ueno, R. Kawai, P. Blandford, T. Chen, G. Kamae, T. Madejski, J. Mizuno, H. Ng, T. Tajima, L. Thurston, A. Barbier, J. Harding, S. Krizmanic, J. Hunter, R. Mitchell, E. Streitmatter, R. Groth, D. Fernholtz, Y. Marlow, T. Saito, S. Takahashi, H. Gunji, Y. Sakurai, V. Fukazawa, P. Anderson, W. Carlson, M. Klamra, M. Pearce, S. Suhonen, F. Larsson, C. I. Ryde, G. Bjornsson, S. Bogaert, Kishimoto

Proceedings of SPIE - The International Society for Optical Engineering 5898 1 - 11 2005年

　概要を見る

The Polarized Gamma-ray Observer (PoGO) is a new balloon-borne instrument designed to measure polarization from astrophysical objects in the 30-200 keV range. It is under development for the first flight anticipated in 2008. PoGO is designed to minimize the background by an improved phoswich configuration, which enables a detection of 10 % polarization in a 100 mCrab source in a 6-8 hour observation. To achieve such high sensitivity, low energy response of the detector is important because the source count rate is generally dominated by the lowest energy photons. We have developed new PMT assemblies specifically designed for PoGO to read-out weak scintillation light of one photoelectron (1 p.e.) level. A beam test of a prototype detector array was conducted at the KEK Photon Factory, Tsukuba in Japan. The experimental data confirm that PoGO can detect polarization of 80-85 % polarized beam down to 30 keV with a modulation factor 0.25 ± 0.05.

DOI
活動銀河核の大規模ジェット：Ｘ線で探る構造とダイナミクス

片岡淳

天文月報 10月号 ( vol.98 ) 680 2005年
Near-infrared, optical, and X-ray observations of the anomalous X-ray pulsar 4U 0142+61

M Morii, N Kawai, J Kataoka, Y Yatsu, N Kobayashi, H Terada

YOUNG NEUTRON STARS AND SUPERNOVA REMNANTS 35 ( 6 ) 1177 - 1180 2005年

　概要を見る

We present results from the simultaneous observations of an anomalous X-ray pulsar (AXP) 4U 0142 + 61 on Sep. 2003. We used RXTE, Subaru, and UH88 telescopes to cover X-ray, near-infrared (NIR) (JHK'), and optical (BVRI) bands, respectively. We obtained a simultaneous broadband spectrum for the first time among AXPs. We found NIR excess in the spectrum, which may be another component different from the optical one. We also found a R band dip. We discuss the broadband spectrum covering the optical and X-ray bands in the framework of a self absorbed synchrotron emission from the magnetosphere of magnetar. We also discuss about the R band dip feature, which could put a restriction on the emission models of magnetars. (c) 2005 Published by Elsevier Ltd on behalf of COSPAR.

DOI
Low energy response of a prototype detector array for the PoGO astronomical hard X-ray polarimeter

J. Kataoka, M. Kanal, T. Arimoto, T. Ikagawa, M. Saito, N. Ueno, R. Kawai, P. Blandford, T. Chen, G. Kamae, T. Madejski, J. Mizuno, H. Ng, T. Tajima, L. Thurston, A. Barbier, J. Harding, S. Krizmanic, J. Hunter, R. Mitchell, E. Streitmatter, R. Groth, D. Fernholtz, Y. Marlow, T. Saito, S. Takahashi, H. Gunji, Y. Sakurai, V. Fukazawa, P. Anderson, W. Carlson, M. Klamra, M. Pearce, S. Suhonen, F. Larsson, C. I. Ryde, G. Bjornsson, S. Bogaert, Kishimoto

Proceedings of SPIE - The International Society for Optical Engineering 5898 1 - 11 2005年

　概要を見る

The Polarized Gamma-ray Observer (PoGO) is a new balloon-borne instrument designed to measure polarization from astrophysical objects in the 30-200 keV range. It is under development for the first flight anticipated in 2008. PoGO is designed to minimize the background by an improved phoswich configuration, which enables a detection of 10 % polarization in a 100 mCrab source in a 6-8 hour observation. To achieve such high sensitivity, low energy response of the detector is important because the source count rate is generally dominated by the lowest energy photons. We have developed new PMT assemblies specifically designed for PoGO to read-out weak scintillation light of one photoelectron (1 p.e.) level. A beam test of a prototype detector array was conducted at the KEK Photon Factory, Tsukuba in Japan. The experimental data confirm that PoGO can detect polarization of 80-85 % polarized beam down to 30 keV with a modulation factor 0.25 ± 0.05.

DOI
Chandra observation of the interaction between the plasma nebula RCW89 and the pulsar jet of PSR B1509-58

Y Yatsu, J Kataoka, N Kawai, K Tamura, W Brinkmann

YOUNG NEUTRON STARS AND SUPERNOVA REMNANTS 35 ( 6 ) 1066 - 1069 2005年

　概要を見る

We present a Chandra observation of the H II region RCW89. The nebula lies 10' north from the central pulsar PSR 131509-58, and it has been suggested that the nebula is irradiated by the pulsar jet. We performed a spectral analysis of the seven brightest emitting regions aligned in a horse-shoe like shape, and found that the temperature of the knots increases along the horse-shoe in the clockwise direction, while, in contrast, the ionization parameter n(e)t decreases. This result implies that RCW89 was heated in sequence. We examined the energy budget assuming that RCW89 is powered by the pulsar jet. The rate of energy injection into RCW89 by the jet was estimated from the synchrotron radiation flux. We obtained a heating time-scale of 1400 yr, which is consistent with the pulsar characteristic age of 1700 yr. To explain the temperature gradient, we discuss the cooling process for plasma clouds in RCW89. We argue that the plasma clumps can be cooled down by the adiabatic expansion within 250 yr, and form the temperature gradient reflecting the sequential heating by the precessing pulsar jet. (c) 2005 COSPAR. Published by Elsevier Ltd. All rights reserved.

DOI
BGO readout with photodiodes as a soft gamma-ray detector at -30 deg

Nakamoto et

Nuclear Instruments and Method section-A 2005 536 - 136 2005年

DOI
HETE-2 localization and observations of the gamma-ray burst GRB 020813

Rie Sato, Takanori Sakamoto, Jun Kataoka, Atsumasa Yoshida, Motoko Suzuki, Junichi Kotoku, Yuji Urata, Yoshihisa Yamamoto, Makoto Arimoto, Toru Tamagawa, Yuji Shirasaki, Ken'ichi Torii, Masaru Matsuoka, Yujin Nakagawa, Toru Yamazaki, Kaoru Tanaka, Miki Maetou, Makoto Yamauchi, Kunio Takagishi, Donald Q. Lamb, Jean-Luc Atteia, Roland Vanderspek, Carlo Graziani, Gregory Prigozhin, Joel Villasenor, J. Garrett Jernigan, Geoffrey B. Crew, Kevin Hurley, George R. Ricker, Stanford E. Woosley, Nat Butler, Al Levine, John P. Doty, Timothy Q. Donaghy, Edward E. Fenimore, Mark Galassi, Michel Boer, Jean-Pascal Dezalay, Jean-François Olive, Joao Braga, Ravi Manchanda, Graziella Pizzichini, Nobuyuki Kawai

Publications of the Astronomical Society of Japan 57 ( 6 ) 1031 - 1039 2005年

　概要を見る

A bright, long gamma-ray burst (GRB) was detected and localized by the instruments on board the High Energy Transient Explorer 2 satellite (HETE-2) at 02:44:19.17 UTC (9859.17 s UT) on 2002 August 13. The location was reported to the GRB Coordinates Network (GCN) about 4 min after the burst. In the prompt emission, the burst had a duration of approximately 125 s, and more than four peaks. We analyzed the time-resolved 2-400 keV energy spectra of the prompt emission of GRB 020813 using the Wide Field X-Ray Monitor (WXM) and the French Gamma Telescope (FREGATE) in detail. We found that the early part of the burst (17-52 s after the burst trigger) shows a depletion of low-energy photons below about 50 keV. It is difficult to explain the depletion by either synchrotron self-absorption or Comptonization. One possibility is that the low-energy depletion may be understood as a mixture of "jitter" radiation with the usual synchrotron radiation component. © 2005. Astronomical Society of Japan.

DOI
Near-infrared, optical, and X-ray observations of the anomalous X-ray pulsar 4U 0142+61

M Morii, N Kawai, J Kataoka, Y Yatsu, N Kobayashi, H Terada

YOUNG NEUTRON STARS AND SUPERNOVA REMNANTS 35 ( 6 ) 1177 - 1180 2005年

　概要を見る

We present results from the simultaneous observations of an anomalous X-ray pulsar (AXP) 4U 0142 + 61 on Sep. 2003. We used RXTE, Subaru, and UH88 telescopes to cover X-ray, near-infrared (NIR) (JHK'), and optical (BVRI) bands, respectively. We obtained a simultaneous broadband spectrum for the first time among AXPs. We found NIR excess in the spectrum, which may be another component different from the optical one. We also found a R band dip. We discuss the broadband spectrum covering the optical and X-ray bands in the framework of a self absorbed synchrotron emission from the magnetosphere of magnetar. We also discuss about the R band dip feature, which could put a restriction on the emission models of magnetars. (c) 2005 Published by Elsevier Ltd on behalf of COSPAR.

DOI
Low energy response of a prototype detector array for the PoGO astronomical hard X-ray polarimeter

J. Kataoka, M. Kanal, T. Arimoto, T. Ikagawa, M. Saito, N. Ueno, R. Kawai, P. Blandford, T. Chen, G. Kamae, T. Madejski, J. Mizuno, H. Ng, T. Tajima, L. Thurston, A. Barbier, J. Harding, S. Krizmanic, J. Hunter, R. Mitchell, E. Streitmatter, R. Groth, D. Fernholtz, Y. Marlow, T. Saito, S. Takahashi, H. Gunji, Y. Sakurai, V. Fukazawa, P. Anderson, W. Carlson, M. Klamra, M. Pearce, S. Suhonen, F. Larsson, C. I. Ryde, G. Bjornsson, S. Bogaert, Kishimoto

Proceedings of SPIE - The International Society for Optical Engineering 5898 1 - 11 2005年

　概要を見る

The Polarized Gamma-ray Observer (PoGO) is a new balloon-borne instrument designed to measure polarization from astrophysical objects in the 30-200 keV range. It is under development for the first flight anticipated in 2008. PoGO is designed to minimize the background by an improved phoswich configuration, which enables a detection of 10 % polarization in a 100 mCrab source in a 6-8 hour observation. To achieve such high sensitivity, low energy response of the detector is important because the source count rate is generally dominated by the lowest energy photons. We have developed new PMT assemblies specifically designed for PoGO to read-out weak scintillation light of one photoelectron (1 p.e.) level. A beam test of a prototype detector array was conducted at the KEK Photon Factory, Tsukuba in Japan. The experimental data confirm that PoGO can detect polarization of 80-85 % polarized beam down to 30 keV with a modulation factor 0.25 ± 0.05.

DOI
Chandra observation of the interaction between the plasma nebula RCW89 and the pulsar jet of PSR B1509-58

Y Yatsu, J Kataoka, N Kawai, K Tamura, W Brinkmann

YOUNG NEUTRON STARS AND SUPERNOVA REMNANTS 35 ( 6 ) 1066 - 1069 2005年

　概要を見る

We present a Chandra observation of the H II region RCW89. The nebula lies 10' north from the central pulsar PSR 131509-58, and it has been suggested that the nebula is irradiated by the pulsar jet. We performed a spectral analysis of the seven brightest emitting regions aligned in a horse-shoe like shape, and found that the temperature of the knots increases along the horse-shoe in the clockwise direction, while, in contrast, the ionization parameter n(e)t decreases. This result implies that RCW89 was heated in sequence. We examined the energy budget assuming that RCW89 is powered by the pulsar jet. The rate of energy injection into RCW89 by the jet was estimated from the synchrotron radiation flux. We obtained a heating time-scale of 1400 yr, which is consistent with the pulsar characteristic age of 1700 yr. To explain the temperature gradient, we discuss the cooling process for plasma clouds in RCW89. We argue that the plasma clumps can be cooled down by the adiabatic expansion within 250 yr, and form the temperature gradient reflecting the sequential heating by the precessing pulsar jet. (c) 2005 COSPAR. Published by Elsevier Ltd. All rights reserved.

DOI
BGO readout with photodiodes as a soft gamma-ray detector at -30 deg

Nakamoto et

Nuclear Instruments and Method section-A 2005 536 - 136 2005年

DOI
HETE-2 localization and observations of the gamma-ray burst GRB 020813

Rie Sato, Takanori Sakamoto, Jun Kataoka, Atsumasa Yoshida, Motoko Suzuki, Junichi Kotoku, Yuji Urata, Yoshihisa Yamamoto, Makoto Arimoto, Toru Tamagawa, Yuji Shirasaki, Ken'ichi Torii, Masaru Matsuoka, Yujin Nakagawa, Toru Yamazaki, Kaoru Tanaka, Miki Maetou, Makoto Yamauchi, Kunio Takagishi, Donald Q. Lamb, Jean-Luc Atteia, Roland Vanderspek, Carlo Graziani, Gregory Prigozhin, Joel Villasenor, J. Garrett Jernigan, Geoffrey B. Crew, Kevin Hurley, George R. Ricker, Stanford E. Woosley, Nat Butler, Al Levine, John P. Doty, Timothy Q. Donaghy, Edward E. Fenimore, Mark Galassi, Michel Boer, Jean-Pascal Dezalay, Jean-François Olive, Joao Braga, Ravi Manchanda, Graziella Pizzichini, Nobuyuki Kawai

Publications of the Astronomical Society of Japan 57 ( 6 ) 1031 - 1039 2005年

　概要を見る

A bright, long gamma-ray burst (GRB) was detected and localized by the instruments on board the High Energy Transient Explorer 2 satellite (HETE-2) at 02:44:19.17 UTC (9859.17 s UT) on 2002 August 13. The location was reported to the GRB Coordinates Network (GCN) about 4 min after the burst. In the prompt emission, the burst had a duration of approximately 125 s, and more than four peaks. We analyzed the time-resolved 2-400 keV energy spectra of the prompt emission of GRB 020813 using the Wide Field X-Ray Monitor (WXM) and the French Gamma Telescope (FREGATE) in detail. We found that the early part of the burst (17-52 s after the burst trigger) shows a depletion of low-energy photons below about 50 keV. It is difficult to explain the depletion by either synchrotron self-absorption or Comptonization. One possibility is that the low-energy depletion may be understood as a mixture of "jitter" radiation with the usual synchrotron radiation component. © 2005. Astronomical Society of Japan.

DOI
Design and performance of soft Gamma-ray detector for NeXT mission

H. Tajima, T. Kamae, G. Madejski, T. Mitani, K. Nakazawa, T. Tanaka, T. Takahashi, S. Watanabe, Y. Fukazawa, T. Ikagawa, J. Kataoka, M. Kokubun, K. Makishima, Y. Terada, M. Nomachi, M. Tashiro

IEEE Nuclear Science Symposium Conference Record 1 314 - 321 2004年12月

　概要を見る

The Soft Gamma-ray Detector (SGD) on board NeXT (Japanese future high energy astrophysics mission) is a Compton telescope with narrow field of view (FOV), which utilizes Compton kinematics to enhance its background rejection capabilities. It is realized as a hybrid semiconductor gamma-ray detector which consists of silicon and CdTe (Cadmium Telluride) detectors. It can detect photons in a wide energy band (0.05-1 MeV) at a background level of 5 × 10-7counts/s/cm2/keV; the silicon layers are required to improve the performance at a lower energy band (<0.3 MeV). Excellent energy resolution is the key feature of the SGD, allowing to achieve both high angular resolution and good background rejection capability. An additional capability of the SGD, its ability to measure gamma-ray polarization opens up a new window to study properties of astronomical objects. We will present the development of key technologies to realize the SGD; high quality CdTe, low noise front-end ASIC and bump bonding tecnology. Energy resolutions of 1.7 keV (FWHM) for CdTe pixel detectors and 1.1 keV for Si strip detectors have been measured. We also present the validation of MC simulation used to evaluate the performance of the SGD. © 2004 IEEE.
28pSD-4 硬 X 線偏光計 PoGO の開発と気球実験への応用 (II)(X 線, 宇宙線)

山下祐一郎, 郡司修一, 河合誠之, 片岡淳, 有元誠, 釜江常好, 水野恒史, 斉藤芳隆, 高橋忠幸, 深沢泰司, Mitchell John W, Streimatter Robert, Marlow Daniel

日本物理学会講演概要集 59 ( 2 ) 79 - 79 2004年08月

CiNii
27aZE-4 Chandra衛星による高温プラズマ雲RCW89とパルサージェットの相互作用の観測(X線)(宇宙線)

谷津陽一, 小谷太郎, 片岡淳, 河合誠之, 田村啓輔

日本物理学会講演概要集 59 ( 1 ) 78 - 78 2004年03月

CiNii
Evolution of the synchrotron spectrum in Markarian 421 during the 1998 campaign

C Tanihata, J Kataoka, T Takahashi, GM Madejski

ASTROPHYSICAL JOURNAL 601 ( 2 ) 759 - 770 2004年02月

　概要を見る

The uninterrupted 7 day ASCA observations of the TeV blazar Mrk 421 in 1998 have clearly revealed that X-ray flares occur repeatedly. In this paper, we present the results of the time-resolved spectral analysis of the combined data taken by ASCA, RXTE, BeppoSAX, and the Extreme Ultraviolet Explorer (EUVE). In this object-and in many other TeV blazars-the precise measurement of the shape of the X-ray spectrum, which reflects the high-energy portion of the synchrotron component, is crucial in determining the high-energy cutoff of the accelerated electrons in the jet. Thanks to the simultaneous broadband coverage, we measured the 0.1-25 keV spectrum resolved on timescales as short as several hours, providing a great opportunity to investigate the detailed spectral evolution at the flares. By analyzing the time-subdivided observations, we parameterize the evolution of the synchrotron peak, where the radiation power dominates, by fitting the combined spectra with a quadratic form [where the nuF(nu) flux at the energy E obeys log nuF(nu)( E)=log (nuF(nu), (peak))-const(log E-log E-peak)(2)]. In this case, we show that there is an overall trend that the peak energy E-peak and peak flux nuF(nu,pea)k increase or decrease together. The relation of the two parameters is best described as E-peak proportional to nuF(nu,peak)(0.7) for the 1998 campaign. Similar results were derived for the 1997 observations, while the relation gave a smaller index when both 1997 and 1998 data were included. On the other hand, we show that this relation, and also the detailed spectral variations, differs from flare to flare within the 1998 campaign. We suggest that the observed features are consistent with the idea that flares are due to the appearance of a new spectral component. With the availability of the simultaneous TeV data, we also show that there exists a clear correlation between the synchrotron peak flux and the TeV flux.

DOI
Evolution of the synchrotron spectrum in Markarian 421 during the 1998 campaign

C Tanihata, J Kataoka, T Takahashi, GM Madejski

ASTROPHYSICAL JOURNAL 601 ( 2 ) 759 - 770 2004年02月

　概要を見る

The uninterrupted 7 day ASCA observations of the TeV blazar Mrk 421 in 1998 have clearly revealed that X-ray flares occur repeatedly. In this paper, we present the results of the time-resolved spectral analysis of the combined data taken by ASCA, RXTE, BeppoSAX, and the Extreme Ultraviolet Explorer (EUVE). In this object-and in many other TeV blazars-the precise measurement of the shape of the X-ray spectrum, which reflects the high-energy portion of the synchrotron component, is crucial in determining the high-energy cutoff of the accelerated electrons in the jet. Thanks to the simultaneous broadband coverage, we measured the 0.1-25 keV spectrum resolved on timescales as short as several hours, providing a great opportunity to investigate the detailed spectral evolution at the flares. By analyzing the time-subdivided observations, we parameterize the evolution of the synchrotron peak, where the radiation power dominates, by fitting the combined spectra with a quadratic form [where the nuF(nu) flux at the energy E obeys log nuF(nu)( E)=log (nuF(nu), (peak))-const(log E-log E-peak)(2)]. In this case, we show that there is an overall trend that the peak energy E-peak and peak flux nuF(nu,pea)k increase or decrease together. The relation of the two parameters is best described as E-peak proportional to nuF(nu,peak)(0.7) for the 1998 campaign. Similar results were derived for the 1997 observations, while the relation gave a smaller index when both 1997 and 1998 data were included. On the other hand, we show that this relation, and also the detailed spectral variations, differs from flare to flare within the 1998 campaign. We suggest that the observed features are consistent with the idea that flares are due to the appearance of a new spectral component. With the availability of the simultaneous TeV data, we also show that there exists a clear correlation between the synchrotron peak flux and the TeV flux.

DOI
NeXTが目指すサイエンス:活動銀河ジェットの物理

片岡淳, 田代信, 深沢泰司

宇宙科学シンポジウム 4 43 - 46 2004年01月

CiNii
宇宙用アバランシェ・フォトダイオードの開発とNeXT衛星への応用

五十川知子, 片岡淳, 谷津陽一

宇宙科学シンポジウム 4 81 - 83 2004年01月

CiNii
Well-type硬X線偏光計PoGOの開発と気球実験への応用

谷津陽一, 片岡淳, 五十川知子

宇宙科学シンポジウム 4 453 - 455 2004年01月

CiNii
学生主導の小型衛星の開発~展工大Cute1.7の現状~

倉本祐輔, 谷津陽一, 片岡淳, 古徳純一, 河合誠之, 五十川知子, 斎藤孝男

日本天文学会年会講演予稿集 2004 2004年

J-GLOBAL
Earliest detection of the optical afterglow of GRB 030329 and its variability

R Sato, N Kawai, M Suzuki, Y Yatsu, J Kataoka, R Takagi, K Yanagisawa, H Yamaoka

GAMMA-RAY BURSTS: 30 YEARS OF DISCOVERY 727 ( No. ) 307 - 311 2004年

　概要を見る

We report the earliest detection of an extremely bright optical afterglow of the gamma-ray burst GRB 030329 using a 30 cm telescope at the Tokyo Institute of Technology (Tokyo, Japan). Our observation started 67 minutes after the burst and continued for two succeeding nights. Combining our data with those reported in GCN Circulars. we find that the early afterglow light curve of the first half day is described by a broken power-law (proportional to t(-alpha)) function with indices alpha(1) = 0.88 +/- 0.01 (0.047 days < t < t(b1)), alpha(2) = 1.18 +/- 0.01 (t(b1) < t < t(b2)), and alpha(3) = 1.81 +/- 0.04 (t(b2) < t < 1.2 days), where t(b1) similar to 0.26 days and t(b2) similar to 0.54 days. respectively. The change of the power-law index at the first break at t similar to 0.26 days is consistent with that expected from a "cooling break".
岡山天体物理観測所のガンマ線バーストフォローアップ50cm望遠鏡

柳澤顕史, 河合誠之, 太田耕司, 渡部潤一, 吉田篤正, 清水康広, 吉田道利, 長山省吾, 稲田素子, 服部尭, 沖田喜一, 岡田隆史, 渡邊悦二, 黒田大介, 戸田博之, 小谷太郎, 片岡淳, 佐藤理江, 鈴木素子, 谷津陽一

日本天文学会年会講演予稿集 2004 231 2004年

J-GLOBAL
宇宙用アバランシェ・フォトダイオードの開発:衛星搭載と撮像への応用

五十川知子, 片岡淳, 斎藤孝男, 谷津陽一, 倉本祐輔, 河合誠之, 深沢泰司, 高橋忠幸, 三谷烈史, 石川嘉隆

日本天文学会年会講演予稿集 2004 260 2004年

J-GLOBAL
Performance of the most recent avalanche photodiodes for future X-ray and gamma-ray astronomy

J Kataoka, T Ikagawa, Y Yatsu, Y Kuramoto, T Saito, N Kawai, Y Serino, J Kotoku, Y Ishikawa, N Kawabata

HIGH-ENERGY DETECTORS IN ASTRONOMY 5501 249 - 260 2004年

　概要を見る

We report on the performance of the most recent avalanche photodiodes produced by Hamamatsu Photonics, as low-energy X-rays and gamma-rays detectors. APDs share good features of both photo diodes and PMTs, as they are very compact, produce an internal gain of 10-100, and have high quantum efficiency close to 100% in the visible right. Until very recently, however, APDs were limited to very small surfaces, and were mainly used as a digital device for light communication. We have developed large area (up to 10x10 mm(2)) APDs which can be used in the physics experiments. The best energy resolution of 6.4% (FWHM) was obtained in direct detection of 5.9 keV X-rays. The FWHM results of 9.4% and 4.9% were obtained for 59.5 keV and 662 keV gamma-rays respectively, as measured with the CsI(Tl) crystal. The minimum detectable energy for the scintillation light was as low as 1 keV at lightly cooled environment (-20degreesC). Note that our results are the best records ever achieved with APDs. Various applications of APDs are presented for future space research and nuclear medicine. In particular 2-dimensional APD arrays will be a promising device for a wide-band X-ray and gamma-ray imaging detector.

DOI
Ground Support Electronics for testing the preflight performance of the MAXI-GSC

J Kataoka, Y Serino, N Kawai, T Arakuni, A Yoshida, M Uzawa, M Kohama, Sakurai, I, T Mihara, H Negoro, N Isobe, H Katayama, K Kawasaki, N Kuramata, M Matsuoka, H Tomida, S Ueno, T Yokota, E Miyata, M Nomachi, H Tsunemi

X-RAY AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY XIII 5165 375 - 386 2004年

　概要を見る

MAXI is an X-ray all-sky monitor which will be mounted on the Japanese Experimental Module (JEM) of the International Space Station (ISS) in 2008. The Gas Slit Camera (GSC) consists of 12 one-dimensional position sensitive proportional counters and the sensitivity will be as high as 1 mCrab for a one-week accumulation in the 2-30 keV band. In order to calibrate the detectors and electronic systems thoroughly before the launch, a fast and versatile Ground Support Electronic (GSE) system is necessary. We have developed a new GSE based on VME I/O boards for a Linux workstation. These boards carry reconfigurable FPGAs of 100,000 gates, together with 16 Mbytes of SDRAM. As a demonstration application of using this GSE, we have tested the positional response of a GSC engineering counter. We present a schematic view of the GSE highlighting the functional design, together with a future vision of the ground testing of the GSC flight counters and digital associated processor.

DOI
Performance of the most recent avalanche photodiodes for future X-ray and gamma-ray astronomy

J Kataoka, T Ikagawa, Y Yatsu, Y Kuramoto, T Saito, N Kawai, Y Serino, J Kotoku, Y Ishikawa, N Kawabata

HIGH-ENERGY DETECTORS IN ASTRONOMY 5501 249 - 260 2004年

　概要を見る

We report on the performance of the most recent avalanche photodiodes produced by Hamamatsu Photonics, as low-energy X-rays and gamma-rays detectors. APDs share good features of both photo diodes and PMTs, as they are very compact, produce an internal gain of 10-100, and have high quantum efficiency close to 100% in the visible right. Until very recently, however, APDs were limited to very small surfaces, and were mainly used as a digital device for light communication. We have developed large area (up to 10x10 mm(2)) APDs which can be used in the physics experiments. The best energy resolution of 6.4% (FWHM) was obtained in direct detection of 5.9 keV X-rays. The FWHM results of 9.4% and 4.9% were obtained for 59.5 keV and 662 keV gamma-rays respectively, as measured with the CsI(Tl) crystal. The minimum detectable energy for the scintillation light was as low as 1 keV at lightly cooled environment (-20degreesC). Note that our results are the best records ever achieved with APDs. Various applications of APDs are presented for future space research and nuclear medicine. In particular 2-dimensional APD arrays will be a promising device for a wide-band X-ray and gamma-ray imaging detector.

DOI
Ground Support Electronics for testing the preflight performance of the MAXI-GSC

J Kataoka, Y Serino, N Kawai, T Arakuni, A Yoshida, M Uzawa, M Kohama, Sakurai, I, T Mihara, H Negoro, N Isobe, H Katayama, K Kawasaki, N Kuramata, M Matsuoka, H Tomida, S Ueno, T Yokota, E Miyata, M Nomachi, H Tsunemi

X-RAY AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY XIII 5165 375 - 386 2004年

　概要を見る

MAXI is an X-ray all-sky monitor which will be mounted on the Japanese Experimental Module (JEM) of the International Space Station (ISS) in 2008. The Gas Slit Camera (GSC) consists of 12 one-dimensional position sensitive proportional counters and the sensitivity will be as high as 1 mCrab for a one-week accumulation in the 2-30 keV band. In order to calibrate the detectors and electronic systems thoroughly before the launch, a fast and versatile Ground Support Electronic (GSE) system is necessary. We have developed a new GSE based on VME I/O boards for a Linux workstation. These boards carry reconfigurable FPGAs of 100,000 gates, together with 16 Mbytes of SDRAM. As a demonstration application of using this GSE, we have tested the positional response of a GSC engineering counter. We present a schematic view of the GSE highlighting the functional design, together with a future vision of the ground testing of the GSC flight counters and digital associated processor.

DOI
Performance of the most recent avalanche photodiodes for future X-ray and gamma-ray astronomy

J Kataoka, T Ikagawa, Y Yatsu, Y Kuramoto, T Saito, N Kawai, Y Serino, J Kotoku, Y Ishikawa, N Kawabata

HIGH-ENERGY DETECTORS IN ASTRONOMY 5501 249 - 260 2004年

　概要を見る

We report on the performance of the most recent avalanche photodiodes produced by Hamamatsu Photonics, as low-energy X-rays and gamma-rays detectors. APDs share good features of both photo diodes and PMTs, as they are very compact, produce an internal gain of 10-100, and have high quantum efficiency close to 100% in the visible right. Until very recently, however, APDs were limited to very small surfaces, and were mainly used as a digital device for light communication. We have developed large area (up to 10x10 mm(2)) APDs which can be used in the physics experiments. The best energy resolution of 6.4% (FWHM) was obtained in direct detection of 5.9 keV X-rays. The FWHM results of 9.4% and 4.9% were obtained for 59.5 keV and 662 keV gamma-rays respectively, as measured with the CsI(Tl) crystal. The minimum detectable energy for the scintillation light was as low as 1 keV at lightly cooled environment (-20degreesC). Note that our results are the best records ever achieved with APDs. Various applications of APDs are presented for future space research and nuclear medicine. In particular 2-dimensional APD arrays will be a promising device for a wide-band X-ray and gamma-ray imaging detector.

DOI
Ground Support Electronics for testing the preflight performance of the MAXI-GSC

J Kataoka, Y Serino, N Kawai, T Arakuni, A Yoshida, M Uzawa, M Kohama, Sakurai, I, T Mihara, H Negoro, N Isobe, H Katayama, K Kawasaki, N Kuramata, M Matsuoka, H Tomida, S Ueno, T Yokota, E Miyata, M Nomachi, H Tsunemi

X-RAY AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY XIII 5165 375 - 386 2004年

　概要を見る

MAXI is an X-ray all-sky monitor which will be mounted on the Japanese Experimental Module (JEM) of the International Space Station (ISS) in 2008. The Gas Slit Camera (GSC) consists of 12 one-dimensional position sensitive proportional counters and the sensitivity will be as high as 1 mCrab for a one-week accumulation in the 2-30 keV band. In order to calibrate the detectors and electronic systems thoroughly before the launch, a fast and versatile Ground Support Electronic (GSE) system is necessary. We have developed a new GSE based on VME I/O boards for a Linux workstation. These boards carry reconfigurable FPGAs of 100,000 gates, together with 16 Mbytes of SDRAM. As a demonstration application of using this GSE, we have tested the positional response of a GSC engineering counter. We present a schematic view of the GSE highlighting the functional design, together with a future vision of the ground testing of the GSC flight counters and digital associated processor.

DOI
Performance of the most recent avalanche photodiodes for future X-ray and gamma-ray astronomy

J Kataoka, T Ikagawa, Y Yatsu, Y Kuramoto, T Saito, N Kawai, Y Serino, J Kotoku, Y Ishikawa, N Kawabata

HIGH-ENERGY DETECTORS IN ASTRONOMY 5501 249 - 260 2004年

　概要を見る

We report on the performance of the most recent avalanche photodiodes produced by Hamamatsu Photonics, as low-energy X-rays and gamma-rays detectors. APDs share good features of both photo diodes and PMTs, as they are very compact, produce an internal gain of 10-100, and have high quantum efficiency close to 100% in the visible right. Until very recently, however, APDs were limited to very small surfaces, and were mainly used as a digital device for light communication. We have developed large area (up to 10x10 mm(2)) APDs which can be used in the physics experiments. The best energy resolution of 6.4% (FWHM) was obtained in direct detection of 5.9 keV X-rays. The FWHM results of 9.4% and 4.9% were obtained for 59.5 keV and 662 keV gamma-rays respectively, as measured with the CsI(Tl) crystal. The minimum detectable energy for the scintillation light was as low as 1 keV at lightly cooled environment (-20degreesC). Note that our results are the best records ever achieved with APDs. Various applications of APDs are presented for future space research and nuclear medicine. In particular 2-dimensional APD arrays will be a promising device for a wide-band X-ray and gamma-ray imaging detector.

DOI
Ground Support Electronics for testing the preflight performance of the MAXI-GSC

J Kataoka, Y Serino, N Kawai, T Arakuni, A Yoshida, M Uzawa, M Kohama, Sakurai, I, T Mihara, H Negoro, N Isobe, H Katayama, K Kawasaki, N Kuramata, M Matsuoka, H Tomida, S Ueno, T Yokota, E Miyata, M Nomachi, H Tsunemi

X-RAY AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY XIII 5165 375 - 386 2004年

　概要を見る

MAXI is an X-ray all-sky monitor which will be mounted on the Japanese Experimental Module (JEM) of the International Space Station (ISS) in 2008. The Gas Slit Camera (GSC) consists of 12 one-dimensional position sensitive proportional counters and the sensitivity will be as high as 1 mCrab for a one-week accumulation in the 2-30 keV band. In order to calibrate the detectors and electronic systems thoroughly before the launch, a fast and versatile Ground Support Electronic (GSE) system is necessary. We have developed a new GSE based on VME I/O boards for a Linux workstation. These boards carry reconfigurable FPGAs of 100,000 gates, together with 16 Mbytes of SDRAM. As a demonstration application of using this GSE, we have tested the positional response of a GSC engineering counter. We present a schematic view of the GSE highlighting the functional design, together with a future vision of the ground testing of the GSC flight counters and digital associated processor.

DOI
Earliest detection of the optical afterglow of GRB 030329 and its variability

R Sato, N Kawai, M Suzuki, Y Yatsu, J Kataoka, R Takagi, K Yanagisawa, H Yamaoka

ASTROPHYSICAL JOURNAL 599 ( 1 ) L9 - L12 2003年12月

　概要を見る

We report the earliest detection of an extremely bright optical afterglow of the gamma-ray burst GRB 030329 using a 30 cm telescope at the Tokyo Institute of Technology ( Tokyo, Japan). Our observation started 67 minutes after the burst and continued for two succeeding nights until the afterglow faded below the sensitivity limit of the telescope (approximately 18 mag). Combining our data with those reported in GCN Circulars, we find that the early afterglow light curve of the first half-day is described by a broken power-law (proportional to(-alpha)) function with indices alpha(1) = 0.88 +/- 0.01 (0.047 days < t <t(b,1)), alpha(2) = 1.18 +/- 0.01 (t(b,1) < t <t(b,2)), and alpha(3) = 1.81 +/- 0.04 (t(b,2) < t < 1.2 days), where t(b,1) similar to 0.26 days and t(b,2) similar to 0.54 days, respectively. The change of the power- law index at the first break at days is consistent with that expected from a " cooling break" when the cooling frequency crossed the optical band. If the interpretation is correct, the decay index before the cooling break implies a uniform interstellar medium environment.

DOI
Earliest detection of the optical afterglow of GRB 030329 and its variability

R Sato, N Kawai, M Suzuki, Y Yatsu, J Kataoka, R Takagi, K Yanagisawa, H Yamaoka

ASTROPHYSICAL JOURNAL 599 ( 1 ) L9 - L12 2003年12月

　概要を見る

We report the earliest detection of an extremely bright optical afterglow of the gamma-ray burst GRB 030329 using a 30 cm telescope at the Tokyo Institute of Technology ( Tokyo, Japan). Our observation started 67 minutes after the burst and continued for two succeeding nights until the afterglow faded below the sensitivity limit of the telescope (approximately 18 mag). Combining our data with those reported in GCN Circulars, we find that the early afterglow light curve of the first half-day is described by a broken power-law (proportional to(-alpha)) function with indices alpha(1) = 0.88 +/- 0.01 (0.047 days < t <t(b,1)), alpha(2) = 1.18 +/- 0.01 (t(b,1) < t <t(b,2)), and alpha(3) = 1.81 +/- 0.04 (t(b,2) < t < 1.2 days), where t(b,1) similar to 0.26 days and t(b,2) similar to 0.54 days, respectively. The change of the power- law index at the first break at days is consistent with that expected from a " cooling break" when the cooling frequency crossed the optical band. If the interpretation is correct, the decay index before the cooling break implies a uniform interstellar medium environment.

DOI
Chandra discovery of an X-ray jet and lobes in 3C 15

J Kataoka, JP Leahy, PG Edwards, M Kino, F Takahara, Y Serino, N Kawai, AR Martel

ASTRONOMY & ASTROPHYSICS 410 ( 3 ) 833 - 845 2003年11月

　概要を見る

We report the Chandra detection of an X-ray jet in 3C 15. The peak of the X-ray emission in the jet is 4.1" ( a projected distance of 5.1 kpc) from the nucleus, and coincident with a component previously identified in the radio and optical jets. We construct the spectral energy distribution ( SED) for this component, optical knot C, and find that X-ray flux is well below the extrapolation of the radio-to-optical continuum. We examine four models for the X-ray jet emission: (I) weak synchrotron cooling in equipartition, (II) moderate synchrotron cooling in equipartition, ( III) weak synchrotron plus synchrotron self-Compton (SSC) cooling, and (IV) moderate synchrotron plus SSC cooling. Given weak evidence for a concave feature in the X-ray spectrum, we argue that case (II) can most reasonably explain the overall emission from knot C. Case (III) is also possible, but requires a large departure from equipartition and for the jet power to be comparable to that of the brightest quasars. In all models, (I)-(IV), electrons must be accelerated up to gamma(max) greater than or similar to 10(7), suggesting that re-acceleration is necessary in knot C of the 3C 15 jet. Diffuse X-ray emission has also been detected, distributed widely over the full extent (63 kpc x 25 kpc) of the radio lobes. The X-ray spectrum of the diffuse emission is described by a two-component model, consisting of soft thermal plasma emission from the host galaxy halo and a hard nonthermal power-law component. The hard component can be ascribed to the inverse Comptonization of cosmic microwave background (CMB) photons by the synchrotron emitting electrons in the radio lobes. We compare the total energy contained in the lobes with the jet power estimated from knot C, and discuss the energetic link between the jet and the lobes. We argue that the fueling time (t(fuel)) and the source age (t(src)) are comparable for case (II), whereas t(fuel) << t(src) is likely for case (III). The latter may imply that the jet has a very small filling factor, similar to 10(-3). We consider the pressure balance between the thermal galaxy halo and non-thermal relativistic electrons in the radio lobes. Finally, we show that the X-ray emission from the nucleus is not adequately fitted by a simple absorbed power-law model, but needs an additional power-law with heavy absorption (N-H similar or equal to 10(22-23) cm(-2)) intrinsic to the source. Such a high column density is consistent with the presence of a dense, dusty torus which obscures the quasar nucleus.

DOI
Chandra discovery of an X-ray jet and lobes in 3C 15

J Kataoka, JP Leahy, PG Edwards, M Kino, F Takahara, Y Serino, N Kawai, AR Martel

ASTRONOMY & ASTROPHYSICS 410 ( 3 ) 833 - 845 2003年11月

　概要を見る

We report the Chandra detection of an X-ray jet in 3C 15. The peak of the X-ray emission in the jet is 4.1" ( a projected distance of 5.1 kpc) from the nucleus, and coincident with a component previously identified in the radio and optical jets. We construct the spectral energy distribution ( SED) for this component, optical knot C, and find that X-ray flux is well below the extrapolation of the radio-to-optical continuum. We examine four models for the X-ray jet emission: (I) weak synchrotron cooling in equipartition, (II) moderate synchrotron cooling in equipartition, ( III) weak synchrotron plus synchrotron self-Compton (SSC) cooling, and (IV) moderate synchrotron plus SSC cooling. Given weak evidence for a concave feature in the X-ray spectrum, we argue that case (II) can most reasonably explain the overall emission from knot C. Case (III) is also possible, but requires a large departure from equipartition and for the jet power to be comparable to that of the brightest quasars. In all models, (I)-(IV), electrons must be accelerated up to gamma(max) greater than or similar to 10(7), suggesting that re-acceleration is necessary in knot C of the 3C 15 jet. Diffuse X-ray emission has also been detected, distributed widely over the full extent (63 kpc x 25 kpc) of the radio lobes. The X-ray spectrum of the diffuse emission is described by a two-component model, consisting of soft thermal plasma emission from the host galaxy halo and a hard nonthermal power-law component. The hard component can be ascribed to the inverse Comptonization of cosmic microwave background (CMB) photons by the synchrotron emitting electrons in the radio lobes. We compare the total energy contained in the lobes with the jet power estimated from knot C, and discuss the energetic link between the jet and the lobes. We argue that the fueling time (t(fuel)) and the source age (t(src)) are comparable for case (II), whereas t(fuel) << t(src) is likely for case (III). The latter may imply that the jet has a very small filling factor, similar to 10(-3). We consider the pressure balance between the thermal galaxy halo and non-thermal relativistic electrons in the radio lobes. Finally, we show that the X-ray emission from the nucleus is not adequately fitted by a simple absorbed power-law model, but needs an additional power-law with heavy absorption (N-H similar or equal to 10(22-23) cm(-2)) intrinsic to the source. Such a high column density is consistent with the presence of a dense, dusty torus which obscures the quasar nucleus.

DOI
Chandra discovery of an X-ray jet and lobes in 3C 15

J Kataoka, JP Leahy, PG Edwards, M Kino, F Takahara, Y Serino, N Kawai, AR Martel

ASTRONOMY & ASTROPHYSICS 410 ( 3 ) 833 - 845 2003年11月

　概要を見る

We report the Chandra detection of an X-ray jet in 3C 15. The peak of the X-ray emission in the jet is 4.1" ( a projected distance of 5.1 kpc) from the nucleus, and coincident with a component previously identified in the radio and optical jets. We construct the spectral energy distribution ( SED) for this component, optical knot C, and find that X-ray flux is well below the extrapolation of the radio-to-optical continuum. We examine four models for the X-ray jet emission: (I) weak synchrotron cooling in equipartition, (II) moderate synchrotron cooling in equipartition, ( III) weak synchrotron plus synchrotron self-Compton (SSC) cooling, and (IV) moderate synchrotron plus SSC cooling. Given weak evidence for a concave feature in the X-ray spectrum, we argue that case (II) can most reasonably explain the overall emission from knot C. Case (III) is also possible, but requires a large departure from equipartition and for the jet power to be comparable to that of the brightest quasars. In all models, (I)-(IV), electrons must be accelerated up to gamma(max) greater than or similar to 10(7), suggesting that re-acceleration is necessary in knot C of the 3C 15 jet. Diffuse X-ray emission has also been detected, distributed widely over the full extent (63 kpc x 25 kpc) of the radio lobes. The X-ray spectrum of the diffuse emission is described by a two-component model, consisting of soft thermal plasma emission from the host galaxy halo and a hard nonthermal power-law component. The hard component can be ascribed to the inverse Comptonization of cosmic microwave background (CMB) photons by the synchrotron emitting electrons in the radio lobes. We compare the total energy contained in the lobes with the jet power estimated from knot C, and discuss the energetic link between the jet and the lobes. We argue that the fueling time (t(fuel)) and the source age (t(src)) are comparable for case (II), whereas t(fuel) << t(src) is likely for case (III). The latter may imply that the jet has a very small filling factor, similar to 10(-3). We consider the pressure balance between the thermal galaxy halo and non-thermal relativistic electrons in the radio lobes. Finally, we show that the X-ray emission from the nucleus is not adequately fitted by a simple absorbed power-law model, but needs an additional power-law with heavy absorption (N-H similar or equal to 10(22-23) cm(-2)) intrinsic to the source. Such a high column density is consistent with the presence of a dense, dusty torus which obscures the quasar nucleus.

DOI
Chandra discovery of an X-ray jet and lobes in 3C 15

J Kataoka, JP Leahy, PG Edwards, M Kino, F Takahara, Y Serino, N Kawai, AR Martel

ASTRONOMY & ASTROPHYSICS 410 ( 3 ) 833 - 845 2003年11月

　概要を見る

We report the Chandra detection of an X-ray jet in 3C 15. The peak of the X-ray emission in the jet is 4.1" ( a projected distance of 5.1 kpc) from the nucleus, and coincident with a component previously identified in the radio and optical jets. We construct the spectral energy distribution ( SED) for this component, optical knot C, and find that X-ray flux is well below the extrapolation of the radio-to-optical continuum. We examine four models for the X-ray jet emission: (I) weak synchrotron cooling in equipartition, (II) moderate synchrotron cooling in equipartition, ( III) weak synchrotron plus synchrotron self-Compton (SSC) cooling, and (IV) moderate synchrotron plus SSC cooling. Given weak evidence for a concave feature in the X-ray spectrum, we argue that case (II) can most reasonably explain the overall emission from knot C. Case (III) is also possible, but requires a large departure from equipartition and for the jet power to be comparable to that of the brightest quasars. In all models, (I)-(IV), electrons must be accelerated up to gamma(max) greater than or similar to 10(7), suggesting that re-acceleration is necessary in knot C of the 3C 15 jet. Diffuse X-ray emission has also been detected, distributed widely over the full extent (63 kpc x 25 kpc) of the radio lobes. The X-ray spectrum of the diffuse emission is described by a two-component model, consisting of soft thermal plasma emission from the host galaxy halo and a hard nonthermal power-law component. The hard component can be ascribed to the inverse Comptonization of cosmic microwave background (CMB) photons by the synchrotron emitting electrons in the radio lobes. We compare the total energy contained in the lobes with the jet power estimated from knot C, and discuss the energetic link between the jet and the lobes. We argue that the fueling time (t(fuel)) and the source age (t(src)) are comparable for case (II), whereas t(fuel) << t(src) is likely for case (III). The latter may imply that the jet has a very small filling factor, similar to 10(-3). We consider the pressure balance between the thermal galaxy halo and non-thermal relativistic electrons in the radio lobes. Finally, we show that the X-ray emission from the nucleus is not adequately fitted by a simple absorbed power-law model, but needs an additional power-law with heavy absorption (N-H similar or equal to 10(22-23) cm(-2)) intrinsic to the source. Such a high column density is consistent with the presence of a dense, dusty torus which obscures the quasar nucleus.

DOI
Variability timescale and jet power of 3C 273

Jun Kataoka, Nobuyuki Kawai

New Astronomy Reviews 47 ( 6-7 ) 685 - 687 2003年10月

書評論文，書評，文献紹介等

　概要を見る

We present the results of a long-look monitoring of 3C 273 with RXTE between 1996 and 2000. A total of 230 observations amounts to a net exposure of 845 ks, with this spectral and variability analysis of 3C 273 covering the longest observation period available at hard X-ray energies. Our new observations imply that 3C 273 is a unique object whose hard X-ray emission occasionally contains a component which is not related to a beamed emission (Seyfert like), but most hard X-rays are likely to originate in inverse Compton radiation from the relativistic jet (blazar like). We consider the 'power balance' (both radiative and kinetic) between the accretion disk, sub-pc-scale jet, and the 10 kpc-scale jet. © 2003 Elsevier B.V. All rights reserveed.

DOI
Chandra observation of the anomalous X-ray pulsar 1E 1841-045

M Morii, R Sato, J Kataoka, N Kawai

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 55 ( 3 ) L45 - L48 2003年06月

　概要を見る

We present the results from a Chandra ACIS CC mode observation of an anomalous X-ray pulsar (AXP) 1E 1841-045. This was the first observation in which the pulsar spectrum over a wide energy range was spatially discriminated from the surrounding SNR, Kes 73. Like other AXPs, the phase-integrated spectrum was fitted well with a power-law plus blackbody model. The spectral parameters are Gamma = 2.0 +/- 0.3, kT(BB) = 0.44 +/- 0.02 keV, and N-H = 2.54(-0.13)(+0.15) x 10(22)cm(-2). This photon index is the flattest among AXPs, and resembles soft gamma-ray repeaters (SGRs) in a quiescent state. The pulse profile is double-peaked, and we found that the second peak has a significantly hard spectrum. The spectra of all phases are consistent with a power-law plus blackbody model with a constant temperature and photon index. When fitted with a two-blackbody model, we obtained a similarly good fit. These results can be interpreted by saying that there are two emission regions with different energy spectra.

DOI
Chandra detection of hotspot and knots of 3C 303

J Kataoka, P Edwards, M Georganopoulos, F Takahara, S Wagner

ASTRONOMY & ASTROPHYSICS 399 ( 1 ) 91 - 97 2003年02月

　概要を見る

We report the detection at X-rays of the radio/optical hotspot and knots of 3C 303 from a short (15 ksec) Chandra exposure in 2001 March. The X-ray morphology is similar to that of the radio/optical emission with peaks in the X-ray emission found at 5.5" (knot B), 9" (knot C) and 17" (hotspot) from the core of 3C 303. Despite the limited signal-to-noise ratio of the short Chandra exposure, the X-ray photon spectrum was measured for the hotspot. We construct the spectral energy distribution (SED) and find that the X-ray flux is well below the extrapolation of the radio-to-optical continuum, which we interpret as resulting from the production of X-rays via inverse Compton scattering of both synchrotron photons (SSC) and cosmic microwave background photons (EC/CMB). The magnetic field strength, region size, and the maximum energy of electrons are self-consistently determined for the hotspot to be B similar or equal to 4.3 muG, R similar or equal to 6.5 x 10(21) cm, and gamma(max) similar or equal to 1.4 x 10(7). This implies a magnetic field strength a factor of similar to30 below the equipartition value; B-eq 150 muG. The origin of this large departure from equipartition is still uncertain, but the discrepancy is reduced if the plasma in the hotspot is moving with mildly relativistic speeds. Our observation of 3C 303, as well as recent Chandra detections of large scale jets and hotspots in a number of radio galaxies, confirm that particles are accelerated very efficiently in radio galaxies.

DOI
Implications of variability patterns observed in TeV blazars on the structure of the inner jet

C Tanihata, T Takahashi, J Kataoka, GM Madejski

ASTROPHYSICAL JOURNAL 584 ( 1 ) 153 - 163 2003年02月

　概要を見る

The recent long-look X-ray observations of TeV blazars have revealed many important new features concerning their time variability. In this paper we suggest a physical interpretation for those features based on the framework of the internal and external shock scenarios. We present a simplified model applicable to TeV blazars and investigate through simulations how each of the model parameters would affect the observed light curve or spectrum. In particular, we show that the internal shock scenario naturally leads to all the observed variability properties, including the structure function, but for it to be applicable, the fractional fluctuation of the initial bulk Lorentz factors must be small, sigma'(Gamma) = sigma(Gamma)/Gamma(avg) << 0.01. This implies very low dynamical efficiency of the internal shock scenario. We also suggest that several observational quantities such as the characteristic timescale, the relative amplitude of flares as compared to the steady ("offset") component, and the slope of the structure function can be used to probe the inner jet. The results are applied to the TeV blazar Mrk 421, and this, within the context of the model, leads to the determination of several physical parameters: the ejection of a shell with average thickness of similar to10(13) cm occurs on average every 10 minutes, and the shells collide similar to10(17) cm away from the central source.

DOI
Chandra detection of hotspot and knots of 3C 303

J Kataoka, P Edwards, M Georganopoulos, F Takahara, S Wagner

ASTRONOMY & ASTROPHYSICS 399 ( 1 ) 91 - 97 2003年02月

　概要を見る

We report the detection at X-rays of the radio/optical hotspot and knots of 3C 303 from a short (15 ksec) Chandra exposure in 2001 March. The X-ray morphology is similar to that of the radio/optical emission with peaks in the X-ray emission found at 5.5" (knot B), 9" (knot C) and 17" (hotspot) from the core of 3C 303. Despite the limited signal-to-noise ratio of the short Chandra exposure, the X-ray photon spectrum was measured for the hotspot. We construct the spectral energy distribution (SED) and find that the X-ray flux is well below the extrapolation of the radio-to-optical continuum, which we interpret as resulting from the production of X-rays via inverse Compton scattering of both synchrotron photons (SSC) and cosmic microwave background photons (EC/CMB). The magnetic field strength, region size, and the maximum energy of electrons are self-consistently determined for the hotspot to be B similar or equal to 4.3 muG, R similar or equal to 6.5 x 10(21) cm, and gamma(max) similar or equal to 1.4 x 10(7). This implies a magnetic field strength a factor of similar to30 below the equipartition value; B-eq 150 muG. The origin of this large departure from equipartition is still uncertain, but the discrepancy is reduced if the plasma in the hotspot is moving with mildly relativistic speeds. Our observation of 3C 303, as well as recent Chandra detections of large scale jets and hotspots in a number of radio galaxies, confirm that particles are accelerated very efficiently in radio galaxies.

DOI
50kg級ガンマ線バースト観測衛星の概念設計

山本佳久, 片岡淳, 河合誠之

宇宙科学シンポジウム 3 507 - 514 2003年01月

CiNii
Chandra Detection of Hot Spot and Knots of 3C303

J.Kataoka

399 91 2003年
Performance of Large Area Avalanche Photodiode as a Low Signal Photon Detector

Ikagawa et

Nuclear Instruments and Method section-A 515 663 2003年
Performance of Large Area Avalanche Photodiode as a Low Signal Photon Detector

Ikagawa et

Nuclear Instruments and Method section-A 515 663 2003年
Implications of Variability Patterns Observed in TeV Blazars on the Structure of the Inner Jet

Tanihata et

The Astrophysical Journal 584 153 2003年

DOI
Chandra Observation of the Anomalous X-Ray Pulsar 1E 1841-045

PASJ

Morii et al. 55 ( 3 ) L45 - 48 2003年

CiNii
Chandra Detection of Hot Spot and Knots of 3C303

J.Kataoka

399 91 2003年
RXTE observations of 3C 273 between 1996 and 2000: variability time-scale and jet power

J Kataoka, C Tanihata, N Kawai, F Takahara, T Takahashi, PG Edwards, F Makino

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 336 ( 3 ) 932 - 944 2002年11月

　概要を見る

We present the results of a long-look monitoring of 3C 273 with RXTE between 1996 and 2000. A total of 230 observations amounts to a net exposure of 845 ks, with this spectral and variability analysis of 3C 273 covering the longest observation period available at hard X-ray energies. Flux variations by a factor of 4 have been detected over 4 yr, whereas flux variations of less than 30 per cent have been observed for individual flares on time-scales of similar to3 d. Two temporal methods, the power spectrum density (PSD) and the structure function (SF), have been used to study the variability characteristics of 3C 273. The hard X-ray photon spectra generally show a power-law shape with a differential photon index of Gamma similar or equal to 1.6 +/- 0.1. In 10 of 261 data segments, exceptions to power-law behaviour have been found: (i) an additional soft excess below 4 keV; and (ii) a broad Fe fluorescent line feature with EW similar to 100-200 eV. Our new observations of these previously reported X-ray features may imply that 3C 273 is a unique object whose hard X-ray emission occasionally contains a component that is not related to a beamed emission (Seyfert-like), but most hard X-rays are likely to originate in inverse Compton radiation from the relativistic jet (blazar-like). Multifrequency spectra from radio to gamma-rays are presented in addition to our RXTE results. The X-ray time variability and spectral evolution are discussed in the framework of the beamed, synchrotron self-Compton picture. We consider the 'power balance' (both radiative and kinetic) between the accretion disc, the sub-parsec-scale jet and the 10-kpc-scale jet.

DOI
RXTE observations of 3C 273 between 1996 and 2000: variability time-scale and jet power

J Kataoka, C Tanihata, N Kawai, F Takahara, T Takahashi, PG Edwards, F Makino

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 336 ( 3 ) 932 - 944 2002年11月

　概要を見る

We present the results of a long-look monitoring of 3C 273 with RXTE between 1996 and 2000. A total of 230 observations amounts to a net exposure of 845 ks, with this spectral and variability analysis of 3C 273 covering the longest observation period available at hard X-ray energies. Flux variations by a factor of 4 have been detected over 4 yr, whereas flux variations of less than 30 per cent have been observed for individual flares on time-scales of similar to3 d. Two temporal methods, the power spectrum density (PSD) and the structure function (SF), have been used to study the variability characteristics of 3C 273. The hard X-ray photon spectra generally show a power-law shape with a differential photon index of Gamma similar or equal to 1.6 +/- 0.1. In 10 of 261 data segments, exceptions to power-law behaviour have been found: (i) an additional soft excess below 4 keV; and (ii) a broad Fe fluorescent line feature with EW similar to 100-200 eV. Our new observations of these previously reported X-ray features may imply that 3C 273 is a unique object whose hard X-ray emission occasionally contains a component that is not related to a beamed emission (Seyfert-like), but most hard X-rays are likely to originate in inverse Compton radiation from the relativistic jet (blazar-like). Multifrequency spectra from radio to gamma-rays are presented in addition to our RXTE results. The X-ray time variability and spectral evolution are discussed in the framework of the beamed, synchrotron self-Compton picture. We consider the 'power balance' (both radiative and kinetic) between the accretion disc, the sub-parsec-scale jet and the 10-kpc-scale jet.

DOI
Observation of gamma rays greater than 10 TeV from Markarian 421

K Okumura, A Asahara, GV Bicknell, PG Edwards, R Enomoto, S Gunji, S Hara, T Hara, S Hayashi, C Itoh, S Kabuki, F Kajino, H Katagiri, J Kataoka, A Kawachi, T Kifune, H Kubo, J Kushida, S Maeda, A Maeshiro, Y Matsubara, Y Mizumoto, M Mori, M Moriya, H Muraishi, Y Muraki, T Naito, T Nakase, K Nishijima, M Ohishi, Patterson, JR, K Sakurazawa, R Suzuki, DL Swaby, K Takano, T Takano, T Tanimori, F Tokanai, K Tsuchiya, H Tsunoo, K Uruma, A Watanabe, S Yanagita, T Yoshida, T Yoshikoshi

ASTROPHYSICAL JOURNAL 579 ( 1 ) L9 - L12 2002年11月

　概要を見る

We have observed Markarian 421 in 2001 January and March with the CANGAROO-II imaging Cerenkov telescope during an extraordinarily high state at TeV energies. From 14 hr of observations at very large zenith angles, similar to70degrees, a signal of 298 +/- 52 gamma-ray-like events (5.7 sigma) was detected at E > 10 TeV, where a higher sensitivity is achieved than those of usual observations near the zenith, owing to a greatly increased collecting area. Under the assumption of an intrinsic power-law spectrum, we derived a differential energy spectrum dN/dE p (3.3 +/- 0.9(stat) +/- 0.3(syst)) x 10(-13) (E/10 TeV)(-(4.0+/-0.60.9, stat +/-0.3syst)) photons cm(-2) s(-1) TeV-1, which is steeper than those previously measured around 1 TeV and supports the evidence for a cutoff in the spectrum of Mrk 421. However, the 4 sigma excess at energies greater than 20 TeV in our data favors a cutoff energy of similar to8 TeV, at the upper end of the range previously reported from measurements at TeV energies.

DOI
Observation of gamma rays greater than 10 TeV from Markarian 421

K Okumura, A Asahara, GV Bicknell, PG Edwards, R Enomoto, S Gunji, S Hara, T Hara, S Hayashi, C Itoh, S Kabuki, F Kajino, H Katagiri, J Kataoka, A Kawachi, T Kifune, H Kubo, J Kushida, S Maeda, A Maeshiro, Y Matsubara, Y Mizumoto, M Mori, M Moriya, H Muraishi, Y Muraki, T Naito, T Nakase, K Nishijima, M Ohishi, Patterson, JR, K Sakurazawa, R Suzuki, DL Swaby, K Takano, T Takano, T Tanimori, F Tokanai, K Tsuchiya, H Tsunoo, K Uruma, A Watanabe, S Yanagita, T Yoshida, T Yoshikoshi

ASTROPHYSICAL JOURNAL 579 ( 1 ) L9 - L12 2002年11月

　概要を見る

We have observed Markarian 421 in 2001 January and March with the CANGAROO-II imaging Cerenkov telescope during an extraordinarily high state at TeV energies. From 14 hr of observations at very large zenith angles, similar to70degrees, a signal of 298 +/- 52 gamma-ray-like events (5.7 sigma) was detected at E > 10 TeV, where a higher sensitivity is achieved than those of usual observations near the zenith, owing to a greatly increased collecting area. Under the assumption of an intrinsic power-law spectrum, we derived a differential energy spectrum dN/dE p (3.3 +/- 0.9(stat) +/- 0.3(syst)) x 10(-13) (E/10 TeV)(-(4.0+/-0.60.9, stat +/-0.3syst)) photons cm(-2) s(-1) TeV-1, which is steeper than those previously measured around 1 TeV and supports the evidence for a cutoff in the spectrum of Mrk 421. However, the 4 sigma excess at energies greater than 20 TeV in our data favors a cutoff energy of similar to8 TeV, at the upper end of the range previously reported from measurements at TeV energies.

DOI
15pRA-4 宇宙ステーション搭載「全天X線監視装置」MAXI(マキシー)の現状(X線,宇宙線)

三原建弘, 根来均, 小浜光洋, 桜井郁也, 中島基樹, 牧島一夫, 松岡勝, 上野史郎, 冨田洋, 磯部直樹, 河合誠之, 片岡淳, 吉田篤正, 常深博, 宮田恵美

日本物理学会講演概要集 57 ( 2 ) 78 - 78 2002年08月

CiNii
Performance of the ASTRO-E hard X-ray detector

M Tashiro, T Kamae, K Makishima, T Takahashi, T Murakami, Y Fukazawa, M Kokubun, K Nakazawa, M Nomachi, A Yoshida, Y Ezoe, N Isobe, N Iyomoto, J Kataoka, J Kotoku, M Kouda, S Kubo, A Kubota, Y Matsumoto, T Mizuno, GM Madejski, Y Okada, N Ota, H Ozawa, G Sato, M Sugiho, M Sugizaki, Takahashi, I, H Takahashi, T Tamura, C Tanihata, Y Terada, Y Uchiyama, S Watanabe, K Yamaoka, D Yonetoku

IEEE TRANSACTIONS ON NUCLEAR SCIENCE 49 ( 4 ) 1893 - 1897 2002年08月

　概要を見る

This paper summarizes the design and performance of the hard X-ray detector constructed for the ASTRO-E satellite. The detector utilizes the GSO/BGO well-type phoswich counters in a compound-eye configuration to achieve an extremely low background level of a few x 10(-5) counts s(-1) cm(-2)keV(-1) [1]. The GSO scintillators installed in the BGO active shield wells are sensitive to 30-600 keV photons, while the 2-mm-thick silicon PIN diodes, placed in front of each GSO crystal, cover the 10-60 keV energy band with a spectral resolution of similar to3.5-keV full-width at half-maximum. The design goals, of both low background and high energy resolution, in the hard X-ray bands were verified through the preflight calibration experiments.

DOI
Performance of the ASTRO-E hard X-ray detector

M Tashiro, T Kamae, K Makishima, T Takahashi, T Murakami, Y Fukazawa, M Kokubun, K Nakazawa, M Nomachi, A Yoshida, Y Ezoe, N Isobe, N Iyomoto, J Kataoka, J Kotoku, M Kouda, S Kubo, A Kubota, Y Matsumoto, T Mizuno, GM Madejski, Y Okada, N Ota, H Ozawa, G Sato, M Sugiho, M Sugizaki, Takahashi, I, H Takahashi, T Tamura, C Tanihata, Y Terada, Y Uchiyama, S Watanabe, K Yamaoka, D Yonetoku

IEEE TRANSACTIONS ON NUCLEAR SCIENCE 49 ( 4 ) 1893 - 1897 2002年08月

　概要を見る

This paper summarizes the design and performance of the hard X-ray detector constructed for the ASTRO-E satellite. The detector utilizes the GSO/BGO well-type phoswich counters in a compound-eye configuration to achieve an extremely low background level of a few x 10(-5) counts s(-1) cm(-2)keV(-1) [1]. The GSO scintillators installed in the BGO active shield wells are sensitive to 30-600 keV photons, while the 2-mm-thick silicon PIN diodes, placed in front of each GSO crystal, cover the 10-60 keV energy band with a spectral resolution of similar to3.5-keV full-width at half-maximum. The design goals, of both low background and high energy resolution, in the hard X-ray bands were verified through the preflight calibration experiments.

DOI
ブレーザーの多波長同時観測と粒子加速への示唆

片岡淳, 高橋忠幸, 谷畑千春, 窪秀利

天文月報 95 ( 8 ) 418 - 425 2002年07月

CiNii
The acceleration of cosmic-ray protons in the supernova remnant RX J1713.7-3946

R Enomoto, T Tanimori, T Naito, T Yoshida, S Yanagita, M Mori, PG Edwards, A Asahara, GV Bicknell, S Gunji, S Hara, T Hara, S Hayashi, C Itoh, S Kabuki, F Kajino, H Katagiri, J Kataoka, A Kawachi, T Kifune, H Kubo, J Kushida, S Maeda, A Maeshiro, Y Matsubara, Y Mizumoto, M Moriya, H Muraishi, Y Muraki, T Nakase, K Nishijima, M Ohishi, K Okumura, Patterson, JR, K Sakurazawa, R Suzuki, DL Swaby, K Takano, T Takano, F Tokanai, K Tsuchiya, H Tsunoo, K Uruma, A Watanabe, T Yoshikoshi

NATURE 416 ( 6883 ) 823 - 826 2002年04月

　概要を見る

Protons with energies up to similar to10(15) eV are the main component(1) of cosmic rays, but evidence for the specific locations where they could have been accelerated to these energies has been lacking(2). Electrons are known to be accelerated to cosmic-ray energies in supernova remnants(3,4), and the shock waves associated with such remnants, when they hit the surrounding interstellar medium, could also provide the energy to accelerate protons. The signature of such a process would be the decay of pions (pi(0)), which are generated when the protons collide with atoms and molecules in an interstellar cloud: pion decay results in gamma-rays with a particular spectral-energy distribution(5,6). Here we report the observation of cascade showers of optical photons resulting from g-rays at energies of similar to10(12) eV hitting Earth's upper atmosphere, in the direction of the supernova remnant RX J1713.7-3946. The spectrum is a good match to that predicted by pion decay, and cannot be explained by other mechanisms.

DOI PubMed CiNii
The acceleration of cosmic-ray protons in the supernova remnant RX J1713.7-3946

R Enomoto, T Tanimori, T Naito, T Yoshida, S Yanagita, M Mori, PG Edwards, A Asahara, GV Bicknell, S Gunji, S Hara, T Hara, S Hayashi, C Itoh, S Kabuki, F Kajino, H Katagiri, J Kataoka, A Kawachi, T Kifune, H Kubo, J Kushida, S Maeda, A Maeshiro, Y Matsubara, Y Mizumoto, M Moriya, H Muraishi, Y Muraki, T Nakase, K Nishijima, M Ohishi, K Okumura, Patterson, JR, K Sakurazawa, R Suzuki, DL Swaby, K Takano, T Takano, F Tokanai, K Tsuchiya, H Tsunoo, K Uruma, A Watanabe, T Yoshikoshi

NATURE 416 ( 6883 ) 823 - 826 2002年04月

　概要を見る

Protons with energies up to similar to10(15) eV are the main component(1) of cosmic rays, but evidence for the specific locations where they could have been accelerated to these energies has been lacking(2). Electrons are known to be accelerated to cosmic-ray energies in supernova remnants(3,4), and the shock waves associated with such remnants, when they hit the surrounding interstellar medium, could also provide the energy to accelerate protons. The signature of such a process would be the decay of pions (pi(0)), which are generated when the protons collide with atoms and molecules in an interstellar cloud: pion decay results in gamma-rays with a particular spectral-energy distribution(5,6). Here we report the observation of cascade showers of optical photons resulting from g-rays at energies of similar to10(12) eV hitting Earth's upper atmosphere, in the direction of the supernova remnant RX J1713.7-3946. The spectrum is a good match to that predicted by pion decay, and cannot be explained by other mechanisms.

DOI PubMed CiNii
ブレーザーの他波長同時か観測と粒子加速への示唆

片岡淳他

天文月報 8月号 ( vol.95 ) 373 2002年
RXTE observations of 3C 273 between 1996 and 2000:Variability Timescale and Jet Power

Kataoka et

Mon. Not. Roy. Astron. Soc. 336 932 2002年

DOI
Design study of CANGAROO-III, stereoscopic imaging atmospheric Cherenkov telescopes for sub-TeV gamma-ray detection

R Enomoto, S Hara, A Asahara, GV Bicknell, PG Edwards, S Gunji, T Hara, J Jimbo, F Kajino, H Katagiri, J Kataoka, A Kawachi, T Kifune, H Kubo, J Kushida, Y Matsubara, Y Mizumoto, M Mori, M Moriya, H Muraishi, Y Muraki, T Naito, T Nakase, K Nishijima, K Okumura, Patterson, JR, K Sakurazawa, DL Swaby, K Takano, T Tanimori, T Tamura, K Tsuchiya, K Uruma, S Yanagita, T Yoshida, T Yoshikoshi, A Yuki

ASTROPARTICLE PHYSICS 16 ( 3 ) 235 - 244 2002年01月

　概要を見る

CANGAROO-III is an imaging atmospheric Cherenkov telescope array of four 10-m telescopes for very high energy (sub-TeV) gamma-ray astronomy. A design study of the CANGAROO-III telescope system was carried out using the Monte Carlo technique in order to optimize the pixel size and the telescope spacing. Studies were also made of observations at low elevation angles. (C) 2002 Elsevier Science B.V. All rights reserved.

DOI
RXTE observations of 3C 273 between 1996 and 2000:Variability Timescale and Jet Power

J.Kataoka

Mon. Not. Roy. Astron. Soc. 336 932 2002年

DOI
Design study of CANGAROO-III, stereoscopic imaging atmospheric Cherenkov telescopes for sub-TeV gamma-ray detection

R Enomoto, S Hara, A Asahara, GV Bicknell, PG Edwards, S Gunji, T Hara, J Jimbo, F Kajino, H Katagiri, J Kataoka, A Kawachi, T Kifune, H Kubo, J Kushida, Y Matsubara, Y Mizumoto, M Mori, M Moriya, H Muraishi, Y Muraki, T Naito, T Nakase, K Nishijima, K Okumura, Patterson, JR, K Sakurazawa, DL Swaby, K Takano, T Tanimori, T Tamura, K Tsuchiya, K Uruma, S Yanagita, T Yoshida, T Yoshikoshi, A Yuki

ASTROPARTICLE PHYSICS 16 ( 3 ) 235 - 244 2002年01月

　概要を見る

CANGAROO-III is an imaging atmospheric Cherenkov telescope array of four 10-m telescopes for very high energy (sub-TeV) gamma-ray astronomy. A design study of the CANGAROO-III telescope system was carried out using the Monte Carlo technique in order to optimize the pixel size and the telescope spacing. Studies were also made of observations at low elevation angles. (C) 2002 Elsevier Science B.V. All rights reserved.

DOI
Variability timescales of TeV blazars observed in the ASCA continuous long-look X-ray monitoring

C Tanihata, CM Urry, T Takahashi, J Kataoka, SJ Wagner, GM Madejski, M Tashiro, M Kouda

ASTROPHYSICAL JOURNAL 563 ( 2 ) 569 - 581 2001年12月

　概要を見る

Three uninterrupted, long (lasting respectively 7, 10, and 10 days) ASCA observations of the well-studied TeV-bright blazars Mrk 421, Mrk 501, and PKS 2155-304 all show continuous strong X-ray flaring. Despite the relatively faint intensity states in two of the three sources, there was no identifiable quiescent period in any of the observations. Structure function analysis shows that all blazars have a characteristic timescale of similar to1 day, comparable to the recurrence time and to the timescale of the stronger flares. On the other hand, examination of these flares in more detail reveals that each of the strong flares is not a smooth increase and decrease but exhibits substructures of shorter flares having timescales of similar to 10 ks. We verify via simulations that in order to explain the observed structure function, these shorter flares ("shots") are unlikely to be fully random, but in some way are correlated with each other. The energy dependent cross-correlation analysis shows that interband lags are not universal in TeV blazars. This is important since in the past only positive detections of lags were reported. In this work, we determine that the sign of a lag may differ from flare to flare; significant lags of both signs were detected from several flares, while no significant lag was detected from others. However, we also argue that the nature of the underlying component can affect these values. The facts that all flares are nearly symmetric and that fast variability shorter than the characteristic timescale is strongly suppressed, support the scenario where the light crossing time dominates the variability timescales of the day-scale flares.

DOI
Variability timescales of TeV blazars observed in the ASCA continuous long-look X-ray monitoring

C Tanihata, CM Urry, T Takahashi, J Kataoka, SJ Wagner, GM Madejski, M Tashiro, M Kouda

ASTROPHYSICAL JOURNAL 563 ( 2 ) 569 - 581 2001年12月

　概要を見る

Three uninterrupted, long (lasting respectively 7, 10, and 10 days) ASCA observations of the well-studied TeV-bright blazars Mrk 421, Mrk 501, and PKS 2155-304 all show continuous strong X-ray flaring. Despite the relatively faint intensity states in two of the three sources, there was no identifiable quiescent period in any of the observations. Structure function analysis shows that all blazars have a characteristic timescale of similar to1 day, comparable to the recurrence time and to the timescale of the stronger flares. On the other hand, examination of these flares in more detail reveals that each of the strong flares is not a smooth increase and decrease but exhibits substructures of shorter flares having timescales of similar to 10 ks. We verify via simulations that in order to explain the observed structure function, these shorter flares ("shots") are unlikely to be fully random, but in some way are correlated with each other. The energy dependent cross-correlation analysis shows that interband lags are not universal in TeV blazars. This is important since in the past only positive detections of lags were reported. In this work, we determine that the sign of a lag may differ from flare to flare; significant lags of both signs were detected from several flares, while no significant lag was detected from others. However, we also argue that the nature of the underlying component can affect these values. The facts that all flares are nearly symmetric and that fast variability shorter than the characteristic timescale is strongly suppressed, support the scenario where the light crossing time dominates the variability timescales of the day-scale flares.

DOI
Characteristic X-ray variability of TeV blazars: Probing the link between the jet and the central engine

J Kataoka, T Takahashi, SJ Wagner, N Iyomoto, PG Edwards, K Hayashida, S Inoue, GM Madejski, F Takahara, C Tanihata, N Kawai

ASTROPHYSICAL JOURNAL 560 ( 2 ) 659 - 674 2001年10月

　概要を見る

We have studied the rapid X-ray variability of three extragalactic TeV gamma -ray sources : Mrk 421, Mrk 501, and PKS 2155-304. Analyzing the X-ray light curves obtained from ASCA and/or Rossi X-Ray Timing Explorer observations between 1993 and 1998, we have investigated the variability in the time domain from 10(3) to 10(8) s. For all three sources, both the power spectrum density (PSD) and the structure function (SF) show a rollover with a timescale of the order of 1 day or longer, which may be interpreted as the typical timescale of successive flare events. Although the exact shape of turnover is not well constrained and the low-frequency (long timescale) behavior is still unclear, the high-frequency (short timescale) behavior is clearly resolved. We found that, on timescales shorter than 1 day, there is only small power in the variability, as indicated by a steep power spectrum density of f(-2 similar to -3). This is very different from other types of mass-accreting black hole systems, for which the short-timescale variability is well characterized by a fractal, flickering-noise PSD (f(-1 similar to -2)). The steep PSD index and the characteristic timescale of flares imply that the X-ray-emitting site in the jet is of limited spatial extent : D greater than or equal to 10(17) cm distant from the base of the jet, which corresponds to greater than or equal to 10(2) Schwarzschild radii for 10(7-10) M-circle dot black hole systems.

DOI
Characteristic X-ray variability of TeV blazars: Probing the link between the jet and the central engine

J Kataoka, T Takahashi, SJ Wagner, N Iyomoto, PG Edwards, K Hayashida, S Inoue, GM Madejski, F Takahara, C Tanihata, N Kawai

ASTROPHYSICAL JOURNAL 560 ( 2 ) 659 - 674 2001年10月

　概要を見る

We have studied the rapid X-ray variability of three extragalactic TeV gamma -ray sources : Mrk 421, Mrk 501, and PKS 2155-304. Analyzing the X-ray light curves obtained from ASCA and/or Rossi X-Ray Timing Explorer observations between 1993 and 1998, we have investigated the variability in the time domain from 10(3) to 10(8) s. For all three sources, both the power spectrum density (PSD) and the structure function (SF) show a rollover with a timescale of the order of 1 day or longer, which may be interpreted as the typical timescale of successive flare events. Although the exact shape of turnover is not well constrained and the low-frequency (long timescale) behavior is still unclear, the high-frequency (short timescale) behavior is clearly resolved. We found that, on timescales shorter than 1 day, there is only small power in the variability, as indicated by a steep power spectrum density of f(-2 similar to -3). This is very different from other types of mass-accreting black hole systems, for which the short-timescale variability is well characterized by a fractal, flickering-noise PSD (f(-1 similar to -2)). The steep PSD index and the characteristic timescale of flares imply that the X-ray-emitting site in the jet is of limited spatial extent : D greater than or equal to 10(17) cm distant from the base of the jet, which corresponds to greater than or equal to 10(2) Schwarzschild radii for 10(7-10) M-circle dot black hole systems.

DOI
Characteristic X-ray variability of TeV blazars: Probing the link between the jet and the central engine

J Kataoka, T Takahashi, SJ Wagner, N Iyomoto, PG Edwards, K Hayashida, S Inoue, GM Madejski, F Takahara, C Tanihata, N Kawai

ASTROPHYSICAL JOURNAL 560 ( 2 ) 659 - 674 2001年10月

　概要を見る

We have studied the rapid X-ray variability of three extragalactic TeV gamma -ray sources : Mrk 421, Mrk 501, and PKS 2155-304. Analyzing the X-ray light curves obtained from ASCA and/or Rossi X-Ray Timing Explorer observations between 1993 and 1998, we have investigated the variability in the time domain from 10(3) to 10(8) s. For all three sources, both the power spectrum density (PSD) and the structure function (SF) show a rollover with a timescale of the order of 1 day or longer, which may be interpreted as the typical timescale of successive flare events. Although the exact shape of turnover is not well constrained and the low-frequency (long timescale) behavior is still unclear, the high-frequency (short timescale) behavior is clearly resolved. We found that, on timescales shorter than 1 day, there is only small power in the variability, as indicated by a steep power spectrum density of f(-2 similar to -3). This is very different from other types of mass-accreting black hole systems, for which the short-timescale variability is well characterized by a fractal, flickering-noise PSD (f(-1 similar to -2)). The steep PSD index and the characteristic timescale of flares imply that the X-ray-emitting site in the jet is of limited spatial extent : D greater than or equal to 10(17) cm distant from the base of the jet, which corresponds to greater than or equal to 10(2) Schwarzschild radii for 10(7-10) M-circle dot black hole systems.

DOI
Characteristic X-ray variability of TeV blazars: Probing the link between the jet and the central engine

J Kataoka, T Takahashi, SJ Wagner, N Iyomoto, PG Edwards, K Hayashida, S Inoue, GM Madejski, F Takahara, C Tanihata, N Kawai

ASTROPHYSICAL JOURNAL 560 ( 2 ) 659 - 674 2001年10月

　概要を見る

We have studied the rapid X-ray variability of three extragalactic TeV gamma -ray sources : Mrk 421, Mrk 501, and PKS 2155-304. Analyzing the X-ray light curves obtained from ASCA and/or Rossi X-Ray Timing Explorer observations between 1993 and 1998, we have investigated the variability in the time domain from 10(3) to 10(8) s. For all three sources, both the power spectrum density (PSD) and the structure function (SF) show a rollover with a timescale of the order of 1 day or longer, which may be interpreted as the typical timescale of successive flare events. Although the exact shape of turnover is not well constrained and the low-frequency (long timescale) behavior is still unclear, the high-frequency (short timescale) behavior is clearly resolved. We found that, on timescales shorter than 1 day, there is only small power in the variability, as indicated by a steep power spectrum density of f(-2 similar to -3). This is very different from other types of mass-accreting black hole systems, for which the short-timescale variability is well characterized by a fractal, flickering-noise PSD (f(-1 similar to -2)). The steep PSD index and the characteristic timescale of flares imply that the X-ray-emitting site in the jet is of limited spatial extent : D greater than or equal to 10(17) cm distant from the base of the jet, which corresponds to greater than or equal to 10(2) Schwarzschild radii for 10(7-10) M-circle dot black hole systems.

DOI
25pSG-3 X線全天監視装置 (MAXI) のデータプロセッサー (DP)

小浜光洋, 三原建弘, 根来均, 山岡和貴, 河合誠之, 片岡淳, 吉田篤正, 松岡勝, 田中剛彦, 山口勝, 田中勲

日本物理学会講演概要集 56 ( 2 ) 47 - 47 2001年09月

CiNii
Evidence for a characteristic time-scale in the X-ray light curves of TeV blazars

Jun Kataoka, Tadayuki Takahashi, Philip G. Edwards, Stefan J. Wagner, Susumu Inoue, Fumio Takahara

AIP Conference Proceedings 558 660 - 663 2001年 [査読有り] [ 国際誌 ] [国際共著]

記事・総説・解説・論説等（国際会議プロシーディングズ）

　概要を見る

We have studied the rapid X-ray variability of four TeV blazars, Mrk 421, Mrk 501, PKS 2155-304 and 1ES 2344+514. Analyzing the X-ray light curves obtained from ASCA and/or RXTE observations, we have investigated the variability in the time domain from 103 to 107 sec. The structure functions show a roll-over around 1 day, which can be interpreted as the typical time-scale of day-by-day flare events. On time-scales shorter than 1 day, variability is significantly suppressed, indicating a steep power spectrum density (PSD) of f-2~-3. This is very different from other types of mass-accreting black-hole systems for which the short timescale variability is well characterized by a fractal, flickering noise (f-1~-2). Importantly, the steep PSD index and the characteristic time-scale of day-by-day flares imply that the X-ray emitting site in the jet is of limited spatial extent; D~=1017-18 cm distant from the base of the jet, which corresponds to ~=102-4Rg for 107-9Msolar black-hole systems.

DOI
活動銀河核からの高エネルギー放射：相対論的ジェットの物理

片岡淳

日本物理学会誌 vol.56 no.3 ( 3 ) 189 - 194 2001年

　概要を見る

近年,米国の天文衛星CGR0は270を越える天体からのガンマ線放射を検出し,高エネルギー宇宙物理の新しい窓を開いた.このうち66天体がブレーザーと呼ばれる活動銀河核である.ブレーザーでは磁場を伴うジェット内部で電子が相対論的速度まで加速され,その非熱的放射がビーミング効果で強められて観測される.本稿では近年の多波長同時観測の成果を中心に,相対論的ジェットにおける物理過程について解説する.

DOI CiNii
Rapid synchrotron flares from BL Lacertae detected by ASCA and RXTE

C Tanihata, T Takahashi, J Kataoka, GM Madejski, S Inoue, H Kubo, F Makino, Mattox, JR, N Kawai

ASTROPHYSICAL JOURNAL 543 ( 1 ) 124 - 130 2000年11月

　概要を見る

We report the variable X-ray emission from BL Lacertae detected in the ASCA ToO observation conducted during the EGRET and RXTE pointings, coincident with the 1997 July outburst. The source showed a historically high state of X-ray, optical, and gamma -ray emission, with its 2-10 keV flux peaking at similar to3.3 x 10(-11) ergs cm(-2) s(-1). This is more than 3 times higher than the value measured by ASCA in 1995. Ne detected two rapid flares that occurred only in the soft X-ray band, while the hard X-ray flux also increased, but decayed with a much longer timescale. Together with the requirement of a very steep and varying power law dominating the soft X-ray band in addition to the hard power law, we suggest that both the high-energy end of the synchrotron spectrum and the hard inverse Compton spectrum were visible in this source during the outburst. We discuss the possible origins of the observed variability timescales, and interpret the short timescales of the soft X-ray variability as reflecting the size of the emission region.

DOI
Rapid synchrotron flares from BL Lacertae detected by ASCA and RXTE

C Tanihata, T Takahashi, J Kataoka, GM Madejski, S Inoue, H Kubo, F Makino, Mattox, JR, N Kawai

ASTROPHYSICAL JOURNAL 543 ( 1 ) 124 - 130 2000年11月

　概要を見る

We report the variable X-ray emission from BL Lacertae detected in the ASCA ToO observation conducted during the EGRET and RXTE pointings, coincident with the 1997 July outburst. The source showed a historically high state of X-ray, optical, and gamma -ray emission, with its 2-10 keV flux peaking at similar to3.3 x 10(-11) ergs cm(-2) s(-1). This is more than 3 times higher than the value measured by ASCA in 1995. Ne detected two rapid flares that occurred only in the soft X-ray band, while the hard X-ray flux also increased, but decayed with a much longer timescale. Together with the requirement of a very steep and varying power law dominating the soft X-ray band in addition to the hard power law, we suggest that both the high-energy end of the synchrotron spectrum and the hard inverse Compton spectrum were visible in this source during the outburst. We discuss the possible origins of the observed variability timescales, and interpret the short timescales of the soft X-ray variability as reflecting the size of the emission region.
Complex spectral variability from intensive multiwavelength monitoring of Markarian 421 in 1998

T Takahashi, J Kataoka, G Madejski, J Mattox, CM Urry, S Wagner, F Aharonian, M Catanese, L Chiappetti, P Coppi, B Degrange, G Fossati, H Kubo, H Krawczynski, F Makino, H Marshall, L Maraschi, F Piron, R Remillard, F Takahara, M Tashiro, H Terasranta, T Weekes

ASTROPHYSICAL JOURNAL 542 ( 2 ) L105 - L109 2000年10月

　概要を見る

We conducted a multifrequency campaign for the TeV blazar Markarian 421 in 1998 April. The campaign started from a pronounced high-amplitude flare recorded by BeppoSAX and Whipple; the ASCA observation started 3 days later. In the X-ray data, we detected multiple flares, occurring on timescales of about 1 day. ASCA data clearly reveal spectral variability. The comparison of the data from ASCA, the Extreme Ultraviolet Explorer, and the Rossi X-Ray Timing Explorer indicates that the variability amplitudes in the low-energy synchrotron component are larger at higher photon energies. In TeV gamma -rays, large intraday variations-which were correlated with the X-ray flux-were observed when results from three Cerenkov telescopes were combined. The rms variability of TeV gamma -rays was similar to that observed in hard X-rays, above 10 keV. The X-ray light curve reveals flares that are almost symmetric for most cases, implying that the dominant timescale is the light crossing time through the emitting region. The structure function analysis based on the continuous X-ray light curve of 7 days indicates that the characteristic timescale is similar to0.5 days. The analysis of ASCA light curves in various energy bands appears to show both soft (positive) and hard (negative) lags. These may not be real, as systematic effects could also produce these lags, which are all much smaller than an orbit. If the lags of both signs are red, these imply that the particle acceleration and X-ray cooling timescales are similar.

DOI
Complex spectral variability from intensive multiwavelength monitoring of Markarian 421 in 1998

T Takahashi, J Kataoka, G Madejski, J Mattox, CM Urry, S Wagner, F Aharonian, M Catanese, L Chiappetti, P Coppi, B Degrange, G Fossati, H Kubo, H Krawczynski, F Makino, H Marshall, L Maraschi, F Piron, R Remillard, F Takahara, M Tashiro, H Terasranta, T Weekes

ASTROPHYSICAL JOURNAL 542 ( 2 ) L105 - L109 2000年10月

　概要を見る

We conducted a multifrequency campaign for the TeV blazar Markarian 421 in 1998 April. The campaign started from a pronounced high-amplitude flare recorded by BeppoSAX and Whipple; the ASCA observation started 3 days later. In the X-ray data, we detected multiple flares, occurring on timescales of about 1 day. ASCA data clearly reveal spectral variability. The comparison of the data from ASCA, the Extreme Ultraviolet Explorer, and the Rossi X-Ray Timing Explorer indicates that the variability amplitudes in the low-energy synchrotron component are larger at higher photon energies. In TeV gamma -rays, large intraday variations-which were correlated with the X-ray flux-were observed when results from three Cerenkov telescopes were combined. The rms variability of TeV gamma -rays was similar to that observed in hard X-rays, above 10 keV. The X-ray light curve reveals flares that are almost symmetric for most cases, implying that the dominant timescale is the light crossing time through the emitting region. The structure function analysis based on the continuous X-ray light curve of 7 days indicates that the characteristic timescale is similar to0.5 days. The analysis of ASCA light curves in various energy bands appears to show both soft (positive) and hard (negative) lags. These may not be real, as systematic effects could also produce these lags, which are all much smaller than an orbit. If the lags of both signs are red, these imply that the particle acceleration and X-ray cooling timescales are similar.
Variability pattern and the spectral evolution of the BL lacertae object PKS 2155-304

J Kataoka, T Takahashi, F Makino, S Inoue, GM Madejski, M Tashiro, CM Urry, H Kubo

ASTROPHYSICAL JOURNAL 528 ( 1 ) 243 - 253 2000年01月

　概要を見る

The TeV blazar PKS 2155 - 304 was monitored with the X-ray satellite ASCA in 1994 May as part of a multiwavelength campaign from the radio to X-ray bands. At the beginning of the two-day continuous observation, we detected a lame flare, in which the 2-10 keV flux changed by a factor of 2 on a timescale of 3 x 10(4) s. During the hare, the increase in the hard X-ray flux clearly preceded that observed in the soft X-rays, with the spectral evolution tracking a "clockwise loop" in the flux versus photon index plane. Ascribing the energy-dependent variability to differential synchrotron cooling of relativistic electrons, we estimate the magnetic field B in the emission region. We tested two different methods of comparing the time series in various X-ray bands: (1) fitting the light curves to a Gaussian function and searching for the time shift of the peak of the flare, and (2) calculating the discrete correlation function. Both methods yielded a consistent solution of B similar to 0.1 G; We also found that the flare amplitude becomes larger as the photon energy increases, while the duration of the flare stays roughly constant throughout the ASCA energy band (0.7-7.5 keV). In the framework of the time-dependent synchrotron self-Compton model in a homogeneous region, we consider a flare where the maximum Lorentz factor (gamma(max)) of the injected electrons increases uniformly throughout the emission volume. The temporal evolution of spectra as well as the light curves were reproduced with the physical parameters self-consistently determined from seven observables. We obtained B similar to 0.1-0.2 G and a region size R similar to 10(-2) pc for relativistic beaming with a Doppler factor of delta similar to 20-30. We discuss the significance of light-travel time effects.
A study of high energy emission from the TeV blazar Mrk 501 during multiwavelength observations in 1996

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartmann, GM Madejski, P Sreekumar, SJ Wagner

BROAD BAND X-RAY SPECTRA OF COSMIC SOURCES 25 ( 3-4 ) 737 - 740 2000年

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in March 1996 with ASCA. EGRET, Whipple, and optical telescopes. We report here for the first time the detection of GeV gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). Higher flux was also observed in April/May 1996, with 4.0 sigma for E > 100 MeV, and 5.2 sigma for E > 500 MeV. We find that the multiband spectrum in March 1996 is consistent with that calculated from a one-zone SSC model, except for the extremely 'flat' TeV spectrum. We show that this flat spectrum cannot be explained by either 2nd order Comptonization or the contribution of the 'seed' IR photons from the host galaxy. (C) 2000 COSPAR. Published by Elsevier Science Ltd.
Variability pattern and the spectral evolution of the BL lacertae object PKS 2155-304

J Kataoka, T Takahashi, F Makino, S Inoue, GM Madejski, M Tashiro, CM Urry, H Kubo

ASTROPHYSICAL JOURNAL 528 ( 1 ) 243 - 253 2000年01月

　概要を見る

The TeV blazar PKS 2155 - 304 was monitored with the X-ray satellite ASCA in 1994 May as part of a multiwavelength campaign from the radio to X-ray bands. At the beginning of the two-day continuous observation, we detected a lame flare, in which the 2-10 keV flux changed by a factor of 2 on a timescale of 3 x 10(4) s. During the hare, the increase in the hard X-ray flux clearly preceded that observed in the soft X-rays, with the spectral evolution tracking a "clockwise loop" in the flux versus photon index plane. Ascribing the energy-dependent variability to differential synchrotron cooling of relativistic electrons, we estimate the magnetic field B in the emission region. We tested two different methods of comparing the time series in various X-ray bands: (1) fitting the light curves to a Gaussian function and searching for the time shift of the peak of the flare, and (2) calculating the discrete correlation function. Both methods yielded a consistent solution of B similar to 0.1 G; We also found that the flare amplitude becomes larger as the photon energy increases, while the duration of the flare stays roughly constant throughout the ASCA energy band (0.7-7.5 keV). In the framework of the time-dependent synchrotron self-Compton model in a homogeneous region, we consider a flare where the maximum Lorentz factor (gamma(max)) of the injected electrons increases uniformly throughout the emission volume. The temporal evolution of spectra as well as the light curves were reproduced with the physical parameters self-consistently determined from seven observables. We obtained B similar to 0.1-0.2 G and a region size R similar to 10(-2) pc for relativistic beaming with a Doppler factor of delta similar to 20-30. We discuss the significance of light-travel time effects.

DOI
A study of high energy emission from the TeV blazar Mrk 501 during multiwavelength observations in 1996

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartmann, GM Madejski, P Sreekumar, SJ Wagner

BROAD BAND X-RAY SPECTRA OF COSMIC SOURCES 25 ( 3-4 ) 737 - 740 2000年

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in March 1996 with ASCA. EGRET, Whipple, and optical telescopes. We report here for the first time the detection of GeV gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). Higher flux was also observed in April/May 1996, with 4.0 sigma for E > 100 MeV, and 5.2 sigma for E > 500 MeV. We find that the multiband spectrum in March 1996 is consistent with that calculated from a one-zone SSC model, except for the extremely 'flat' TeV spectrum. We show that this flat spectrum cannot be explained by either 2nd order Comptonization or the contribution of the 'seed' IR photons from the host galaxy. (C) 2000 COSPAR. Published by Elsevier Science Ltd.
Variability pattern and the spectral evolution of the BL lacertae object PKS 2155-304

J Kataoka, T Takahashi, F Makino, S Inoue, GM Madejski, M Tashiro, CM Urry, H Kubo

ASTROPHYSICAL JOURNAL 528 ( 1 ) 243 - 253 2000年01月

　概要を見る

The TeV blazar PKS 2155 - 304 was monitored with the X-ray satellite ASCA in 1994 May as part of a multiwavelength campaign from the radio to X-ray bands. At the beginning of the two-day continuous observation, we detected a lame flare, in which the 2-10 keV flux changed by a factor of 2 on a timescale of 3 x 10(4) s. During the hare, the increase in the hard X-ray flux clearly preceded that observed in the soft X-rays, with the spectral evolution tracking a "clockwise loop" in the flux versus photon index plane. Ascribing the energy-dependent variability to differential synchrotron cooling of relativistic electrons, we estimate the magnetic field B in the emission region. We tested two different methods of comparing the time series in various X-ray bands: (1) fitting the light curves to a Gaussian function and searching for the time shift of the peak of the flare, and (2) calculating the discrete correlation function. Both methods yielded a consistent solution of B similar to 0.1 G; We also found that the flare amplitude becomes larger as the photon energy increases, while the duration of the flare stays roughly constant throughout the ASCA energy band (0.7-7.5 keV). In the framework of the time-dependent synchrotron self-Compton model in a homogeneous region, we consider a flare where the maximum Lorentz factor (gamma(max)) of the injected electrons increases uniformly throughout the emission volume. The temporal evolution of spectra as well as the light curves were reproduced with the physical parameters self-consistently determined from seven observables. We obtained B similar to 0.1-0.2 G and a region size R similar to 10(-2) pc for relativistic beaming with a Doppler factor of delta similar to 20-30. We discuss the significance of light-travel time effects.
A study of high energy emission from the TeV blazar Mrk 501 during multiwavelength observations in 1996

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartmann, GM Madejski, P Sreekumar, SJ Wagner

BROAD BAND X-RAY SPECTRA OF COSMIC SOURCES 25 ( 3-4 ) 737 - 740 2000年

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in March 1996 with ASCA. EGRET, Whipple, and optical telescopes. We report here for the first time the detection of GeV gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). Higher flux was also observed in April/May 1996, with 4.0 sigma for E > 100 MeV, and 5.2 sigma for E > 500 MeV. We find that the multiband spectrum in March 1996 is consistent with that calculated from a one-zone SSC model, except for the extremely 'flat' TeV spectrum. We show that this flat spectrum cannot be explained by either 2nd order Comptonization or the contribution of the 'seed' IR photons from the host galaxy. (C) 2000 COSPAR. Published by Elsevier Science Ltd.
Variability Pattern and the Spectral Evolution of the BL Lacertae Object PKS 2155-304

J.Kataoka

The Astrophysical Journal 528 ( 1 ) 243 - 253 2000年

DOI
A study of high energy emission from the TeV blazar Mrk 501 during multiwavelength observations in 1996

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartmann, GM Madejski, P Sreekumar, SJ Wagner

BROAD BAND X-RAY SPECTRA OF COSMIC SOURCES 25 ( 3-4 ) 737 - 740 2000年

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in March 1996 with ASCA. EGRET, Whipple, and optical telescopes. We report here for the first time the detection of GeV gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). Higher flux was also observed in April/May 1996, with 4.0 sigma for E > 100 MeV, and 5.2 sigma for E > 500 MeV. We find that the multiband spectrum in March 1996 is consistent with that calculated from a one-zone SSC model, except for the extremely 'flat' TeV spectrum. We show that this flat spectrum cannot be explained by either 2nd order Comptonization or the contribution of the 'seed' IR photons from the host galaxy. (C) 2000 COSPAR. Published by Elsevier Science Ltd.
Thick and large area PIN diodes for hard X-ray astronomy

N Ota, T Murakami, M Sugizaki, H Kaneda, T Tamura, H Ozawa, T Kamae, K Makishima, T Takahashi, M Tashiro, Y Fukazawa, J Kataoka, K Yamaoka, S Kubo, C Tanihata, Y Uchiyama, K Matsuzaki, N Iyomoto, M Kokubun, T Nakazawa, A Kubota, T Mizuno, Y Matsumoto, N Isobe, Y Terada, M Sugiho, T Onishi, H Kubo, H Ikeda, M Nomachi, T Ohsugi, M Muramatsu, H Akahori

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 436 ( 1-2 ) 291 - 296 1999年10月

　概要を見る

Thick and large area PIN diodes for the hard X-ray astronomy in the 10-60 keV range are developed. To cover this energy range in a room temperature and in a low background environment, Si PIN junction diodes of 2 mm in thickness with 2.5 cm(2) in effective area were developed, and will be used in the bottom of the Phoswich Hard X-ray Detector (HXD), on-board the ASTRO-E satellite. Problems related to a high purity Si and a thick depletion layer during our development and performance of the PIN diodes are presented in detail. (C) 1999 Elsevier Science B.V. All rights reserved.

DOI CiNii
Thick and large area PIN diodes for hard X-ray astronomy

N Ota, T Murakami, M Sugizaki, H Kaneda, T Tamura, H Ozawa, T Kamae, K Makishima, T Takahashi, M Tashiro, Y Fukazawa, J Kataoka, K Yamaoka, S Kubo, C Tanihata, Y Uchiyama, K Matsuzaki, N Iyomoto, M Kokubun, T Nakazawa, A Kubota, T Mizuno, Y Matsumoto, N Isobe, Y Terada, M Sugiho, T Onishi, H Kubo, H Ikeda, M Nomachi, T Ohsugi, M Muramatsu, H Akahori

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 436 ( 1-2 ) 291 - 296 1999年10月

　概要を見る

Thick and large area PIN diodes for the hard X-ray astronomy in the 10-60 keV range are developed. To cover this energy range in a room temperature and in a low background environment, Si PIN junction diodes of 2 mm in thickness with 2.5 cm(2) in effective area were developed, and will be used in the bottom of the Phoswich Hard X-ray Detector (HXD), on-board the ASTRO-E satellite. Problems related to a high purity Si and a thick depletion layer during our development and performance of the PIN diodes are presented in detail. (C) 1999 Elsevier Science B.V. All rights reserved.

DOI CiNii
Multiwavelength observations of the TeV blazar Mrk 501 in March 1996. The first report of the detection by EGRET

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartman, GM Madejski, P Sreekumar, SJ Wagner

ASTROPARTICLE PHYSICS 11 ( 1-2 ) 149 - 151 1999年06月

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in March 1996 with ASCA, EGRET, Whipple, and optical telescopes. We report here for the first time the detection of a GeV gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). A higher flux was also observed in April/May 1996, with 4.0 sigma significance for E > 100 MeV, and 5.2 sigma significance for E > 500 MeV. We find that the multiband spectrum in March 1996 is consistent with that calculated from a one-zone SSC model, except for the extremely 'flat' TeV spectrum. We show that the discrepancy cannot be explained by either second order Comptonization or the contribution of the 'seed' IR photons from the host galaxy. (C) 1999 Elsevier Science B.V. All rights reserved.
Multiwavelength observations of the TeV blazar Mrk 501 in March 1996. The first report of the detection by EGRET

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartman, GM Madejski, P Sreekumar, SJ Wagner

ASTROPARTICLE PHYSICS 11 ( 1-2 ) 149 - 151 1999年06月

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in March 1996 with ASCA, EGRET, Whipple, and optical telescopes. We report here for the first time the detection of a GeV gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). A higher flux was also observed in April/May 1996, with 4.0 sigma significance for E > 100 MeV, and 5.2 sigma significance for E > 500 MeV. We find that the multiband spectrum in March 1996 is consistent with that calculated from a one-zone SSC model, except for the extremely 'flat' TeV spectrum. We show that the discrepancy cannot be explained by either second order Comptonization or the contribution of the 'seed' IR photons from the host galaxy. (C) 1999 Elsevier Science B.V. All rights reserved.
Multiwavelength observations of the TeV blazar Mrk 501 in March 1996. The first report of the detection by EGRET

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartman, GM Madejski, P Sreekumar, SJ Wagner

ASTROPARTICLE PHYSICS 11 ( 1-2 ) 149 - 151 1999年06月

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in March 1996 with ASCA, EGRET, Whipple, and optical telescopes. We report here for the first time the detection of a GeV gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). A higher flux was also observed in April/May 1996, with 4.0 sigma significance for E > 100 MeV, and 5.2 sigma significance for E > 500 MeV. We find that the multiband spectrum in March 1996 is consistent with that calculated from a one-zone SSC model, except for the extremely 'flat' TeV spectrum. We show that the discrepancy cannot be explained by either second order Comptonization or the contribution of the 'seed' IR photons from the host galaxy. (C) 1999 Elsevier Science B.V. All rights reserved.
Multiwavelength observations of the TeV blazar Mrk 501 in March 1996. The first report of the detection by EGRET

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartman, GM Madejski, P Sreekumar, SJ Wagner

ASTROPARTICLE PHYSICS 11 ( 1-2 ) 149 - 151 1999年06月

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in March 1996 with ASCA, EGRET, Whipple, and optical telescopes. We report here for the first time the detection of a GeV gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). A higher flux was also observed in April/May 1996, with 4.0 sigma significance for E > 100 MeV, and 5.2 sigma significance for E > 500 MeV. We find that the multiband spectrum in March 1996 is consistent with that calculated from a one-zone SSC model, except for the extremely 'flat' TeV spectrum. We show that the discrepancy cannot be explained by either second order Comptonization or the contribution of the 'seed' IR photons from the host galaxy. (C) 1999 Elsevier Science B.V. All rights reserved.
High-energy emission from the TeV blazar Markarian 501 during multiwavelength observations in 1996

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartman, GM Madejski, P Sreekumar, SJ Wagner

ASTROPHYSICAL JOURNAL 514 ( 1 ) 138 - 147 1999年03月

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in 1996 March with ASCA, EGRET, Whipple, and optical telescopes. The X-ray flux observed with ASCA was 5 times higher than the quiescent level and gradually decreased by a factor of 2 during the observation in 1996 March. In the X-ray band, a spectral break was observed around 2 keV. We report here for the first time the detection of high-energy gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). Higher flux was also observed in 1996 April-May, with 4.0 sigma significance for E > 100 MeV and 5.2 sigma significance for E > 500 MeV. The gamma-ray spectrum was measured to be flatter than most of the gamma-ray blazars. We find that the multiband spectrum in 1996 is consistent with that calculated from a one-zone synchrotron self-Compton (SSC) model in which X-rays are produced via synchrotron emission and gamma-rays are produced via inverse Compton scattering of synchrotron photons in a homogeneous region. The flux of TeV gamma-rays is consistent with the predictions of the model if the decrease of the Compton scattering cross section in the Klein-Nishina regime is considered. In the context of this model, we investigate the values of the magnetic field strength and the beaming factor allowed by the observational results. We compare the 1996 March multiwavelength spectrum with that in the flare state in 1997 April. Between these two epochs, the TeV flux increase is well correlated with that observed in keV range. The keV and TeV amplitudes during the 1997 April hare are accurately reproduced by a one-zone SSC model, assuming that the population of synchrotron photons in 1996 are scattered by newly injected relativistic electrons having maximum energies of gamma(max) similar to 6 x 10(6). However, the TeV spectrum observed during the 1996 March campaign is flatter than predicted by our models. We find that this cannot be explained by either higher order Comptonization or the contribution of the "seed" IR photons from the host galaxy for the first-order external radiation. Comptonization, but we cannot exclude possible effects of the IR photons that may arise in the parsec-size tori postulated to exist in active galactic nuclei.

DOI
High-energy emission from the TeV blazar Markarian 501 during multiwavelength observations in 1996

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartman, GM Madejski, P Sreekumar, SJ Wagner

ASTROPHYSICAL JOURNAL 514 ( 1 ) 138 - 147 1999年03月

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in 1996 March with ASCA, EGRET, Whipple, and optical telescopes. The X-ray flux observed with ASCA was 5 times higher than the quiescent level and gradually decreased by a factor of 2 during the observation in 1996 March. In the X-ray band, a spectral break was observed around 2 keV. We report here for the first time the detection of high-energy gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). Higher flux was also observed in 1996 April-May, with 4.0 sigma significance for E > 100 MeV and 5.2 sigma significance for E > 500 MeV. The gamma-ray spectrum was measured to be flatter than most of the gamma-ray blazars. We find that the multiband spectrum in 1996 is consistent with that calculated from a one-zone synchrotron self-Compton (SSC) model in which X-rays are produced via synchrotron emission and gamma-rays are produced via inverse Compton scattering of synchrotron photons in a homogeneous region. The flux of TeV gamma-rays is consistent with the predictions of the model if the decrease of the Compton scattering cross section in the Klein-Nishina regime is considered. In the context of this model, we investigate the values of the magnetic field strength and the beaming factor allowed by the observational results. We compare the 1996 March multiwavelength spectrum with that in the flare state in 1997 April. Between these two epochs, the TeV flux increase is well correlated with that observed in keV range. The keV and TeV amplitudes during the 1997 April hare are accurately reproduced by a one-zone SSC model, assuming that the population of synchrotron photons in 1996 are scattered by newly injected relativistic electrons having maximum energies of gamma(max) similar to 6 x 10(6). However, the TeV spectrum observed during the 1996 March campaign is flatter than predicted by our models. We find that this cannot be explained by either higher order Comptonization or the contribution of the "seed" IR photons from the host galaxy for the first-order external radiation. Comptonization, but we cannot exclude possible effects of the IR photons that may arise in the parsec-size tori postulated to exist in active galactic nuclei.
High-energy emission from the TeV blazar Markarian 501 during multiwavelength observations in 1996

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartman, GM Madejski, P Sreekumar, SJ Wagner

ASTROPHYSICAL JOURNAL 514 ( 1 ) 138 - 147 1999年03月

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in 1996 March with ASCA, EGRET, Whipple, and optical telescopes. The X-ray flux observed with ASCA was 5 times higher than the quiescent level and gradually decreased by a factor of 2 during the observation in 1996 March. In the X-ray band, a spectral break was observed around 2 keV. We report here for the first time the detection of high-energy gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). Higher flux was also observed in 1996 April-May, with 4.0 sigma significance for E > 100 MeV and 5.2 sigma significance for E > 500 MeV. The gamma-ray spectrum was measured to be flatter than most of the gamma-ray blazars. We find that the multiband spectrum in 1996 is consistent with that calculated from a one-zone synchrotron self-Compton (SSC) model in which X-rays are produced via synchrotron emission and gamma-rays are produced via inverse Compton scattering of synchrotron photons in a homogeneous region. The flux of TeV gamma-rays is consistent with the predictions of the model if the decrease of the Compton scattering cross section in the Klein-Nishina regime is considered. In the context of this model, we investigate the values of the magnetic field strength and the beaming factor allowed by the observational results. We compare the 1996 March multiwavelength spectrum with that in the flare state in 1997 April. Between these two epochs, the TeV flux increase is well correlated with that observed in keV range. The keV and TeV amplitudes during the 1997 April hare are accurately reproduced by a one-zone SSC model, assuming that the population of synchrotron photons in 1996 are scattered by newly injected relativistic electrons having maximum energies of gamma(max) similar to 6 x 10(6). However, the TeV spectrum observed during the 1996 March campaign is flatter than predicted by our models. We find that this cannot be explained by either higher order Comptonization or the contribution of the "seed" IR photons from the host galaxy for the first-order external radiation. Comptonization, but we cannot exclude possible effects of the IR photons that may arise in the parsec-size tori postulated to exist in active galactic nuclei.
High-energy emission from the TeV blazar Markarian 501 during multiwavelength observations in 1996

J Kataoka, Mattox, JR, J Quinn, H Kubo, F Makino, T Takahashi, S Inoue, RC Hartman, GM Madejski, P Sreekumar, SJ Wagner

ASTROPHYSICAL JOURNAL 514 ( 1 ) 138 - 147 1999年03月

　概要を見る

We present the results of a multiwavelength campaign for Mrk 501 performed in 1996 March with ASCA, EGRET, Whipple, and optical telescopes. The X-ray flux observed with ASCA was 5 times higher than the quiescent level and gradually decreased by a factor of 2 during the observation in 1996 March. In the X-ray band, a spectral break was observed around 2 keV. We report here for the first time the detection of high-energy gamma-ray flux from Mrk 501 with EGRET with 3.5 sigma significance (E > 100 MeV). Higher flux was also observed in 1996 April-May, with 4.0 sigma significance for E > 100 MeV and 5.2 sigma significance for E > 500 MeV. The gamma-ray spectrum was measured to be flatter than most of the gamma-ray blazars. We find that the multiband spectrum in 1996 is consistent with that calculated from a one-zone synchrotron self-Compton (SSC) model in which X-rays are produced via synchrotron emission and gamma-rays are produced via inverse Compton scattering of synchrotron photons in a homogeneous region. The flux of TeV gamma-rays is consistent with the predictions of the model if the decrease of the Compton scattering cross section in the Klein-Nishina regime is considered. In the context of this model, we investigate the values of the magnetic field strength and the beaming factor allowed by the observational results. We compare the 1996 March multiwavelength spectrum with that in the flare state in 1997 April. Between these two epochs, the TeV flux increase is well correlated with that observed in keV range. The keV and TeV amplitudes during the 1997 April hare are accurately reproduced by a one-zone SSC model, assuming that the population of synchrotron photons in 1996 are scattered by newly injected relativistic electrons having maximum energies of gamma(max) similar to 6 x 10(6). However, the TeV spectrum observed during the 1996 March campaign is flatter than predicted by our models. We find that this cannot be explained by either higher order Comptonization or the contribution of the "seed" IR photons from the host galaxy for the first-order external radiation. Comptonization, but we cannot exclude possible effects of the IR photons that may arise in the parsec-size tori postulated to exist in active galactic nuclei.
Preflight performance of the ASTRO-E hard-x-ray detector

OTA Naomi, Tanihata, C, Kataoka, J, Murakami, T, Ota, N, Ozawa, H, Takahashi, T, Tamura, T, Uchiyama, Y, Watanabe, S, Yamaoka, K, Yonetoku, D, Ezoe, Y, Fukazawa, Y, Isobe, N, Iyomoto, N

Proc. SPIE 3765 645 - 663 1999年

　概要を見る

The Hard X-ray Detector (HXD) is one of the three experiments of the Astro-E mission, the fifth Japanese X-ray satellite devoted to studies of high energy phenomena in the universe in the X-ray to soft gamma-ray region. Prepared for launch at the beginning of 2000 via the newly developed M-V launch vehicle of the Institute of Space and Astronautical Science, the Astro-E is to be thrown into a near-circular orbit of 550 km altitude, with an inclination of 31 degrees. The flight model has been finished assembled this year, and we carried out various tests to verify the performance. We acquired the background spectrum at sea level, and confirmed that our system is operating effectively in reducing the background level. The HXD will observe photons in the energy range of 10-600 keV, and the calculations based on the preflight calibration suggest that the HXD will have the highest sensitivity ever achieved in this energy range. We also verified that our electronic system will maintain its performance against charged particle events expected in orbit.
Activation of the ASTRO-E hard X-ray detector in low earth orbit

M. Kokubun, Y. Fukazawa, E. Idesawa, J. Kataoka, T. Kamae, K. Matsuzaki, T. Mizuno, Y. Saito, T. Takahashi, K. Takizawa, M. Tashiro, T. Tamura, A. Yoshida

IEEE Transactions on Nuclear Science 46 ( 3 ) 371 - 376 1999年

　概要を見る

ASTRO-E Hard X-ray Detector (HXD) is characterized by well-type phoswich counters[1] in a compound-eye configuration which reduce the detector background to lower level than any other past hard X-ray mission. When operating in Low Earth Orbit, the expected background of the HXD is an order of 10 -5 counts/s/kcV/cm 2, mainly caused from the radioactivity induced within the detector materials by geomagnetically trapped protons. Results are presented from measurements of induced radioactivity in two phoswich scintillators, GSO (Gd 2SiO 5:Ce 0.5% mol) and BGO (Bi 4Ge 3O 12), irradiated by mono-energetic protons at an accelerator facility. Radiation transport computer codes are used to build the detector response functions for emissions from decays of spallation products. Based on the comparison between experimental and simulation results, the activation background level of HXD in the orbit is estimated. © 1999 IEEE.

DOI CiNii
Activation of the ASTRO-E hard X-ray detector in low earth orbit

M. Kokubun, Y. Fukazawa, E. Idesawa, J. Kataoka, T. Kamae, K. Matsuzaki, T. Mizuno, Y. Saito, T. Takahashi, K. Takizawa, M. Tashiro, T. Tamura, A. Yoshida

IEEE Transactions on Nuclear Science 46 ( 3 ) 371 - 376 1999年

　概要を見る

ASTRO-E Hard X-ray Detector (HXD) is characterized by well-type phoswich counters[1] in a compound-eye configuration which reduce the detector background to lower level than any other past hard X-ray mission. When operating in Low Earth Orbit, the expected background of the HXD is an order of 10 -5 counts/s/kcV/cm 2, mainly caused from the radioactivity induced within the detector materials by geomagnetically trapped protons. Results are presented from measurements of induced radioactivity in two phoswich scintillators, GSO (Gd 2SiO 5:Ce 0.5% mol) and BGO (Bi 4Ge 3O 12), irradiated by mono-energetic protons at an accelerator facility. Radiation transport computer codes are used to build the detector response functions for emissions from decays of spallation products. Based on the comparison between experimental and simulation results, the activation background level of HXD in the orbit is estimated. © 1999 IEEE.

DOI CiNii
2a-J-5 ASTRO-E搭載硬X線検出器アナログ処理回路の開発(phoswich-I)

谷畑千春, 片岡淳, 寺田幸功, 水野恒史, 江澤元, 田代信, 深沢泰司, 高橋忠幸, 牧島一夫, 釜江常好, 森國城

日本物理学会講演概要集 53 ( 1 ) 80 - 80 1998年03月

CiNii
30p-H-2 宇宙硬X線用井戸型フォスウイッチカウンターに用いるフォトチューブの評価試験

寺田幸功, 水野恒史, 深沢泰司, 牧島一夫, 釜江常好, 高橋忠幸, 片岡淳, 谷畑千春, HXDチーム

日本物理学会講演概要集 53 ( 1 ) 56 - 56 1998年03月

CiNii
Verification of the Astro-E Hard X-ray Detector based on newly developed Ground Support Equipment

J Kataoka, M Nomachi, T Takahashi, G Kawaguchi, Y Terada, T Murakami, C Tanihata, Y Uchiyama, K Yamaoka, Y Fukazawa, T Kamae, K Makishima, M Tashiro, H Kubo

EUV, X-RAY, AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY IX 3445 143 - 154 1998年

　概要を見る

We report the first results of the ground test of the Hard X-ray Detector (HXD) on board the Astro-E mission, by means of the newly developed Ground Support Equipment (GSE). Astro-E will be launched in 2000 by a Japanese M-V rocket. In order to verify the detector system during the limited time before launch, fast and versatile GSE is necessary. For this, we have developed a flexible test system based on nine VME I/O boards for a SUN workstation. These boards carry reconfigurable Field Programmable Gate Arrays (FPGAs) with 50,000 gates, together with 1 Mbyte SRAM devices tightly coupled to each FPGA device. As an application of using this GSE, we have tested the performance of a phoswich unit of the Flight Model of the HXD. In this paper, we present a schematic view of the GSE highlighting the functional design, and the results of our ground test of the HXD-sensor under the high count rate environment (similar to 10 kHz/unit) expected in orbit.
Verification of the Astro-E Hard X-ray Detector based on newly developed Ground Support Equipment

J Kataoka, M Nomachi, T Takahashi, G Kawaguchi, Y Terada, T Murakami, C Tanihata, Y Uchiyama, K Yamaoka, Y Fukazawa, T Kamae, K Makishima, M Tashiro, H Kubo

EUV, X-RAY, AND GAMMA-RAY INSTRUMENTATION FOR ASTRONOMY IX 3445 143 - 154 1998年

　概要を見る

We report the first results of the ground test of the Hard X-ray Detector (HXD) on board the Astro-E mission, by means of the newly developed Ground Support Equipment (GSE). Astro-E will be launched in 2000 by a Japanese M-V rocket. In order to verify the detector system during the limited time before launch, fast and versatile GSE is necessary. For this, we have developed a flexible test system based on nine VME I/O boards for a SUN workstation. These boards carry reconfigurable Field Programmable Gate Arrays (FPGAs) with 50,000 gates, together with 1 Mbyte SRAM devices tightly coupled to each FPGA device. As an application of using this GSE, we have tested the performance of a phoswich unit of the Flight Model of the HXD. In this paper, we present a schematic view of the GSE highlighting the functional design, and the results of our ground test of the HXD-sensor under the high count rate environment (similar to 10 kHz/unit) expected in orbit.
30p-YM-8 天体硬X線検出器用無機シンチレーターGSO, BGOの放射化実験

国分紀秀, 出澤恵理子, 片岡淳, 釜江常好, 斎藤芳隆, 高橋忠幸, 滝沢京子, 田代信, 深沢泰司, 牧島一夫, 松崎恵一, 水野恒史, 吉田篤正, HXDチーム

日本物理学会講演概要集 52 ( 1 ) 74 - 74 1997年03月

CiNii
30p-YM-7 Astro-E衛星搭載硬X線検出器の放射化実験

滝沢京子, 出澤恵理子, 片岡淳, 釜江常好, 国分紀秀, 齋藤芳隆, 高橋忠幸, 田代信, 深沢泰司, 牧島一夫, 松崎恵一, 水野恒史, 吉田篤正, HXDチーム

日本物理学会講演概要集 52 ( 1 ) 74 - 74 1997年03月

CiNii
30p-YM-9 Astro-E搭載硬X線検出器(HXD)用のGSOscintillatorsの性能評価

大曽根聡子, 片岡淳, 山岡和貴, 高橋忠幸, HXDチーム, 久保田あや, 松崎恵一, 釜江常好, 深沢泰司, 齋藤芳隆, 江沢元, 国分紀秀, 水野恒史

日本物理学会講演概要集 52 ( 0 ) 1997年

CiNii
Development of the hard X-ray detector for the ASTRO-E mission

T Takahashi, H Ezawa, Y Fukazawa, M Hirayama, E Idesawa, H Ikeda, Y Ishisaki, N Iyomoto, T Kamae, J Kataoka, H Kaneda, H Kubo, K Makishima, K Matsushita, K Matsuzaki, T Mizuno, T Murakami, K Nagata, S Nakamae, M Nomachi, H Obayashi, T Ohtsuka, H Ozawa, Y Saito, M Sugizaki, T Tamura, M Tashiro, N Tsuchida, K Tsukada, A Yoshida

ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES 120 ( 4 ) C645 - C648 1996年12月

　概要を見る

The Hard X-ray Detector (HXD) is one of three instruments on the fifth Japanese X-ray astronomy satellite, ASTRO-E, scheduled for launch in 2000. The HXD consists of a 4x4 = 16 modular assembly of identical counters, each consisting of a combination of YAP(or GSO)/BGO well-type phoswich counters and silicon PIN diodes. The field of view of the detector for high energy photons is restricted to 4 degrees x 4 degrees by active collimators made of BGO and the fov for low energy photons is restricted to 0.5 degrees x 0.5 degrees by the fine passive collimators made of phosphor bronze. The detector is characterized by a low background reaching severalx10(-6) c/s/cm(2)/keV. Combined with the other two instruments for soft X-ray observations (0.5-12 keV), the ASTRO-E mission will cover the entire range of soft and hard X-rays with the highest sensitivity ever achieved. Furthermore, thick EGO counters which surround the 4x4 matrix of well-type phoswich counters act as a gamma-ray burst detector in the energy band of 100-2000 keV.
Development of the hard X-ray detector for the ASTRO-E mission

T Takahashi, H Ezawa, Y Fukazawa, M Hirayama, E Idesawa, H Ikeda, Y Ishisaki, N Iyomoto, T Kamae, J Kataoka, H Kaneda, H Kubo, K Makishima, K Matsushita, K Matsuzaki, T Mizuno, T Murakami, K Nagata, S Nakamae, M Nomachi, H Obayashi, T Ohtsuka, H Ozawa, Y Saito, M Sugizaki, T Tamura, M Tashiro, N Tsuchida, K Tsukada, A Yoshida

ASTRONOMY & ASTROPHYSICS SUPPLEMENT SERIES 120 ( 4 ) C645 - C648 1996年12月

　概要を見る

The Hard X-ray Detector (HXD) is one of three instruments on the fifth Japanese X-ray astronomy satellite, ASTRO-E, scheduled for launch in 2000. The HXD consists of a 4x4 = 16 modular assembly of identical counters, each consisting of a combination of YAP(or GSO)/BGO well-type phoswich counters and silicon PIN diodes. The field of view of the detector for high energy photons is restricted to 4 degrees x 4 degrees by active collimators made of BGO and the fov for low energy photons is restricted to 0.5 degrees x 0.5 degrees by the fine passive collimators made of phosphor bronze. The detector is characterized by a low background reaching severalx10(-6) c/s/cm(2)/keV. Combined with the other two instruments for soft X-ray observations (0.5-12 keV), the ASTRO-E mission will cover the entire range of soft and hard X-rays with the highest sensitivity ever achieved. Furthermore, thick EGO counters which surround the 4x4 matrix of well-type phoswich counters act as a gamma-ray burst detector in the energy band of 100-2000 keV.
ASCA observation of an X-ray/TeV flare from the BL Lacertae object Markarian 421

T Takahashi, M Tashiro, G Madejski, H Kubo, T Kamae, J Kataoka, T Kii, F Makino, K Makishima, N Yamasaki

ASTROPHYSICAL JOURNAL 470 ( 2 ) L89 - L92 1996年10月

　概要を見る

We observed the BL Lac object Mrk 421 with the X-ray satellite ASCA in 1994 as part of a multifrequency observation. The 24 hr observation was conducted 1 day after the onset of a TeV flare detected by the Whipple Observatory and detected an X-ray flare, with no apparent variability in the optical, UV, and EGRET GeV flux. The ASCA 2-10 keV flux peaked at 3.7 x 10(-10) ergs cm(-2) s(-1) and then decreased to 1.8 x 10(-10) ergs cm(-2) s(-1) with a doubling timescale of similar to 12 hr. The shape of the X-ray spectrum varied during the observation, such that the hard X-rays always led the soft X-rays, both in brightening and dimming of the source, with a lag of the 0.5-1 keV photons versus those in the 2-7.5 keV band of similar to 1 hr. The rapid TeV variability indicates a compact TeV-producing region, suggesting relativistic beaming with a Doppler factor delta greater than or equal to 5. The correlation of the flux in the X-ray and the TeV bands indicates that a high-energy tail of a single electron population is responsible for both X-rays and TeV gamma-rays, with radio, IR, UV and X-rays produced via the synchrotron process and GeV and TeV gamma-rays produced via Comptonization. Under the assumption that the ''soft lag'' observed in the X-ray band is due to the synchrotron-lifetime effects, with delta = 5, we calculate the magnetic field for the X-ray-producing region to be similar to 0.2 G. The Lorentz factors gamma(el) of the electrons responsible for the emission in the keV and TeV bands are similar to 10(6), consistent with the values implied by the Klein-Nishina limit.
ASCA observation of an X-ray/TeV flare from the BL Lacertae object Markarian 421

T Takahashi, M Tashiro, G Madejski, H Kubo, T Kamae, J Kataoka, T Kii, F Makino, K Makishima, N Yamasaki

ASTROPHYSICAL JOURNAL 470 ( 2 ) L89 - L92 1996年10月

　概要を見る

We observed the BL Lac object Mrk 421 with the X-ray satellite ASCA in 1994 as part of a multifrequency observation. The 24 hr observation was conducted 1 day after the onset of a TeV flare detected by the Whipple Observatory and detected an X-ray flare, with no apparent variability in the optical, UV, and EGRET GeV flux. The ASCA 2-10 keV flux peaked at 3.7 x 10(-10) ergs cm(-2) s(-1) and then decreased to 1.8 x 10(-10) ergs cm(-2) s(-1) with a doubling timescale of similar to 12 hr. The shape of the X-ray spectrum varied during the observation, such that the hard X-rays always led the soft X-rays, both in brightening and dimming of the source, with a lag of the 0.5-1 keV photons versus those in the 2-7.5 keV band of similar to 1 hr. The rapid TeV variability indicates a compact TeV-producing region, suggesting relativistic beaming with a Doppler factor delta greater than or equal to 5. The correlation of the flux in the X-ray and the TeV bands indicates that a high-energy tail of a single electron population is responsible for both X-rays and TeV gamma-rays, with radio, IR, UV and X-rays produced via the synchrotron process and GeV and TeV gamma-rays produced via Comptonization. Under the assumption that the ''soft lag'' observed in the X-ray band is due to the synchrotron-lifetime effects, with delta = 5, we calculate the magnetic field for the X-ray-producing region to be similar to 0.2 G. The Lorentz factors gamma(el) of the electrons responsible for the emission in the keV and TeV bands are similar to 10(6), consistent with the values implied by the Klein-Nishina limit.

DOI
ASCA Observations of X-ray/TeV Flare from Mkn 421

Takahashi et a

Mem. Della Soc.Astr. Ital. 67 533 1996年
ASCA Observations of X-ray/TeV Flare from Mkn 421

Takahashi et a

Mem. Della Soc.Astr. Ital. 67 533 1996年
A SEARCH FOR MASSIVE NEUTRAL BOSONS IN ORTHOPOSITRONIUM DECAY

T MAENO, M FUJIKAWA, J KATAOKA, Y NISHIHARA, S ORITO, K SHIGEKUNI, Y WATANABE

PHYSICS LETTERS B 351 ( 4 ) 574 - 578 1995年06月

　概要を見る

We have searched for an exotic decay of orthopositronium into a single photon and a short-lived neutral boson in the hitherto unexplored mass region above 900 keV/c(2), by noting that this decay is one of few remaining candidates which could explain the discrepancy of the orthopositronium decay rate. A high-resolution measurement of the associated photon energy spectrum was carried out with a germanium detector to search for a sharp peak from this two-body decay. Our negative result provides an upper limit of 2.0 x 10(-4) on the branching ratio of such a decay in the mass region from 847 to 1013 keV/c(2), and excludes the possibility of this decay mode explaining the discrepancy in the orthopositronium decay rate.

DOI CiNii
A SEARCH FOR MASSIVE NEUTRAL BOSONS IN ORTHOPOSITRONIUM DECAY

T MAENO, M FUJIKAWA, J KATAOKA, Y NISHIHARA, S ORITO, K SHIGEKUNI, Y WATANABE

PHYSICS LETTERS B 351 ( 4 ) 574 - 578 1995年06月

　概要を見る

We have searched for an exotic decay of orthopositronium into a single photon and a short-lived neutral boson in the hitherto unexplored mass region above 900 keV/c(2), by noting that this decay is one of few remaining candidates which could explain the discrepancy of the orthopositronium decay rate. A high-resolution measurement of the associated photon energy spectrum was carried out with a germanium detector to search for a sharp peak from this two-body decay. Our negative result provides an upper limit of 2.0 x 10(-4) on the branching ratio of such a decay in the mass region from 847 to 1013 keV/c(2), and excludes the possibility of this decay mode explaining the discrepancy in the orthopositronium decay rate.

DOI CiNii
Temperature effects in reverse-type avalanche photodiodes

Mitsuhiro Sato, Takayuki Yanagida, Akira Yoshikawa, Yoichi Yatsu, Jun Kataoka, Fumio Saito

2007 IEEE NUCLEAR SCIENCE SYMPOSIUM CONFERENCE RECORD, VOLS 1-11 1491 - + 1905年06月 [査読有り]

　概要を見る

These The present paper shows ionization coefficient ratios, k-values, k(1) and k(eff), of reverse-type Si avalanche photodiode. Both of k(eff) and k(1), tend to increase when APDs are cooled down. The results for k(eff) are 0.0023 +/- 0.0002 at 20 degrees C, 0.0027 +/- 0.0003 at 0 degrees C, and 0.0049 +/- 0.0007 at -20 degrees C. With the result of k(1), temperature dependency of k-values indicates mean free paths of the carriers for phonon scattering shows different temperature dependency, which is considered to reflect the inner structure of APDs.

▼全件表示

産業財産権

放射性物質の三次元分布を計測する方法及びその装置

片岡淳, 岩本康弘, 岸本彩

特許権
コンプトンカメラ

6191957

片岡淳, 西山徹

特許権
コンプトンカメラ

5991519

岸本彩, 加藤卓也, 片岡淳

特許権
放射線検出器

6145248

片岡淳, 岸本彩

特許権
携帯型放射線検出器

片岡淳

特許権

その他

Scientific...

　概要を見る

Scientific Organizing Committe for
(1) "15-years of Chandra", Nov. Harvard Center for Astrophysics, Boston, USA, Nov, 2014
(2) "The Many Faces of Centaurus A",r June-July 2009, Sydney, Australia
(3) "Radio Galaxies in Chandra Era", July, 2008, Cambridge, USA
(4) "Workshop on Blazar Variability across the Electromagnetic Spectrum", Apri, 2008, Paris, France

現在担当している科目

理工学基礎実験１Ｂ　IIブロック

基幹理工学部

2024年秋学期
理工学基礎実験１Ａ　IIブロック

基幹理工学部

2024年春学期
理工学基礎実験１Ｂ　IIブロック

創造理工学部

2024年秋学期
力学Ｃ　経営(1)

創造理工学部

2024年春学期
理工学基礎実験１Ａ　IIブロック

創造理工学部

2024年春学期
Scientific Research

先進理工学部

2024年春学期
宇宙素粒子実験学概論

先進理工学部

2024年秋学期
物理実験Ｂ　　【前年度成績S評価者用】

先進理工学部

2024年通年
Current Topics in Physics

先進理工学部

2024年秋学期
物理実験Ｂ

先進理工学部

2024年通年
卒業研究【前年度成績S評価者用】

先進理工学部

2024年通年
卒業研究

先進理工学部

2024年通年
物理入門　（物理）　【前年度成績S評価者用】

先進理工学部

2024年春学期
物理入門　（物理）

先進理工学部

2024年春学期
理工学基礎実験１Ａ　IIブロック

先進理工学部

2024年春学期
理工学基礎実験１Ｂ　IIブロック

先進理工学部

2024年秋学期
宇宙素粒子実験学概論

先進理工学部

2024年秋学期
Current Topics in Physics

先進理工学部

2024年秋学期
応用物理学実験Ｂ

先進理工学部

2024年通年
応用物理学実験Ｂ　【前年度成績S評価者用】

先進理工学部

2024年通年
卒業研究　　【前年度成績S評価者用】

先進理工学部

2024年通年
卒業研究

先進理工学部

2024年通年
物理入門　（応物）　【前年度成績S評価者用】

先進理工学部

2024年春学期
物理実験Ａ

先進理工学部

2024年通年
物理入門　（応物）

先進理工学部

2024年春学期
Graduation Thesis Fall [S Grade]

先進理工学部

2024年秋学期
Graduation Thesis Fall

先進理工学部

2024年秋学期
Graduation Thesis Spring [S Grade]

先進理工学部

2024年春学期
Graduation Thesis Spring

先進理工学部

2024年春学期
Current Topics in Physics [S Grade]

先進理工学部

2024年秋学期
Current Topics in Physics

先進理工学部

2024年秋学期
Research on Applied Radiation Physics

大学院先進理工学研究科

2024年通年
Seminar on Applied Radiation Physics C

大学院先進理工学研究科

2024年春学期
放射線応用物理学演習Ｄ

大学院先進理工学研究科

2024年秋学期
放射線応用物理学演習Ｃ

大学院先進理工学研究科

2024年春学期
放射線応用物理学研究

大学院先進理工学研究科

2024年通年
Master's Thesis (Department of Pure and Applied Physics)

大学院先進理工学研究科

2024年通年
修士論文（物理応物）

大学院先進理工学研究科

2024年通年
Seminar on Applied Radiation Physics D

大学院先進理工学研究科

2024年秋学期
物理学及応用物理学海外特別演習Ｃ

大学院先進理工学研究科

2024年通年
物理学及応用物理学海外特別演習Ｂ

大学院先進理工学研究科

2024年通年
物理学及応用物理学海外特別演習Ｄ

大学院先進理工学研究科

2024年通年
物理学及応用物理学海外特別演習Ａ

大学院先進理工学研究科

2024年通年
放射線応用物理学研究

大学院先進理工学研究科

2024年通年

▼全件表示

他学部・他研究科等兼任情報

理工学術院大学院先進理工学研究科

学内研究所・附属機関兼任歴

2022年

-

2024年

理工学術院総合研究所兼任研究員