2022/01/21 更新

写真a

カタオカ ジュン
片岡 淳
所属
理工学術院 先進理工学部
職名
教授

兼担

  • 理工学術院   大学院先進理工学研究科

学内研究所等

  • 2020年
    -
    2022年

    理工学術院総合研究所   兼任研究員

学歴

  • 1997年04月
    -
    2000年03月

    東京大学   大学院理学系研究科・物理学専攻  

  • 1995年04月
    -
    1997年03月

    東京大学   大学院理学系研究科・物理学専攻  

  • 1991年04月
    -
    1995年03月

    東京大学   理学部   物理学科  

学位

  • 東京大学   博士(理学)

経歴

  • 2017年04月
    -
     

    JAXA宇宙機応用工学研究系 客員教授

  • 2014年04月
    -
     

    早稲田大学理工学術院 教授

  • 2009年04月
    -
    2014年03月

    早稲田大学理工学術院 准教授

  • 2006年04月
    -
    2010年03月

    JST 先端計測技術開発プログラム・プロジェクトリーダー

  • 2007年04月
    -
    2009年03月

    東京工業大学 大学院理工学研究科 助教

  • 2001年04月
    -
    2007年03月

    東京工業大学 大学院理工学研究科 助手

  • 2000年04月
    -
    2001年03月

    日本学術振興会 特別研究員(PD)

  • 2000年04月
    -
    2001年03月

    日本学術振興会 特別研究員(PD)

  • 1997年04月
    -
    2000年03月

    日本学術振興会 特別研究員(DC1)

  • 1997年04月
    -
    2000年03月

    日本学術振興会 特別研究員(DC1)

▼全件表示

所属学協会

  •  
     
     

    医学物理学会

  •  
     
     

    日本天文学会

  •  
     
     

    日本物理学会

  •  
     
     

    日本応用物理学会

 

研究分野

  • 量子ビーム科学

  • 放射線科学

  • 医用システム

  • 天文学

  • 素粒子、原子核、宇宙線、宇宙物理にする理論

研究キーワード

  • 次世代放射線検出器開発

  • 放射線イメージング

  • 医学物理

  • 高エネルギー宇宙物理

研究シーズ

論文

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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]

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  • 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

  • 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]

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  • 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

  • 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]

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  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 「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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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 &gt; 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

  • 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 (&gt;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

  • 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

  • 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

  • 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  2016年08月  [査読有り]  [招待有り]

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

    <p>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。</p>

    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

    <p>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。</p>

    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

  • 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

  • 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.&#039; 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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 )  2015年09月

    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

  • 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

  • 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 &lt; 20 degrees and latitude 5 degrees less than or similar to vertical bar b vertical bar &lt; 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 &gt; 0 degrees) favors (ii), whereas that of the south (b &lt; 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

  • 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   77 - 89  2015年07月  [査読有り]

    DOI

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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 &lt; i &lt; 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 &lt; 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

  • 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 &lt; i &lt; 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 &lt; 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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 &lt; 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

  • “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

  • 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

  • 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

  • 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

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  • 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&quot; 1ES 0347-121 and the &quot;extreme blazar candidate&quot; 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

  • 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

  • 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 NGC≠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 NGC≠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 NGC≠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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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 )  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

  • 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

  • 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

  • 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

  • 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

  • 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 &gt;= 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

  • 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

  • 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

  • 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) &lt; 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) &lt; 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

  • 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

  • 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 &lt;= 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

  • 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 &gt; 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

  • 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. 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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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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 &lt;= 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 &lt;= 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

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  • 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

  • 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

  • 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

  • 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

  • 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]

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  • 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

  • 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]

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  • 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]

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  • CONSTRAINING THE HIGH-ENERGY EMISSION FROM GAMMA-RAY BURSTS WITH FERMI

    ASTROPHYSICAL JOURNAL   754 ( 2 )  2012年08月  [査読有り]

    DOI

  • 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.

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  • 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]

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  • 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.

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  • 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]

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  • 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

  • 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]

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  • 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

  • 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

  • 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.

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  • 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

  • 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

  • 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

  • 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

  • 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

  • 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 &gt; 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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   542 - 553  2012年

  • 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

  • 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

  • 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 )  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

  • 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]

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  • 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

  • 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

  • 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]

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  • 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

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  • 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]

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  • 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

  • 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

  • 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

  • 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

  • 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.

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  • 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]

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  • 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

  • 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.

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  • 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

  • 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]

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  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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 )  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 )  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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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) &lt; 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

  • 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.

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  • 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]

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  • 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]

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  • 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.

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  • 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.

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  • 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]

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  • 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]

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  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • Fermi Gamma-Ray Imaging of a Radio Galaxy

    SCIENCE   328 ( 5979 ) 725 - 729  2010年05月  [査読有り]

    DOI

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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.

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  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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]

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  • 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

  • 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]

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  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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 &gt; 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 (&gt;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 &lt; 3.72 x 10(-8) ph (&gt;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  [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 &gt; 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 &gt; 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  [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| &gt; 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| &lt; 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

  • 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

  • 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 (&gt;=-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  [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

  • 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 (&lt;= 10%) and low dark noise (&lt;= 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

  • 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

  • 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 &gt; 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  [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 &gt;= 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 &lt;= 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

  • 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

  • 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

  • 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

  • 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.

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  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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

  • Simultaneous Observations of PKS 2155-304 with HESS, Fermi, RXTE, and Atom: Spectral Energy Distributions and Variability in a Low State

    Aharonian et

    The Astrophysical Journal   696   L150  2009年  [査読有り]

  • Discovery of Pulsed γ-Rays from the Young Radio Pulsar PSR J1028&#8211;5819 with the Fermi Large Area Telescope

    Abdo et

    The Astrophysical Journal   695   L72  2009年  [査読有り]

  • 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

  • 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

  • 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

  • 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.

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  • 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

  • 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 (&lt; 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.

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  • 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

  • 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.

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  • 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.

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  • 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.

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  • 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

  • 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

  • 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.

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  • 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

  • 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

  • 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

  • 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  [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

  • 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

  • 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.

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  • 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.

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  • 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.

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  • 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.

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  • 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

  • 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

  • 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.

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  • 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.

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  • 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 (&gt;= 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.

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  • 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

  • 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.

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  • 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.

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  • 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.

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  • 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

  • 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

  • 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.

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  • 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.

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  • 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

  • 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 ( &gt;= 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

  • 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

  • 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

  • Wide Range Multifrequency Observations of Northern TeV Blazars

    Rugamer

    Astronomische Nachrichten   328   623  2007年

  • The X-ray Observatory Suzaku

    Mitsuda et

    PASJ   59   1  2007年  [査読有り]

  • Suzaku Observations of HESS J 1616-508: Evidence for a Dark Particle Accelerator

    Matsumoto e

    PASJ   59   199  2007年  [査読有り]

  • 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 RCW86

    Ueno et al

    PASJ   59   171  2007年  [査読有り]

  • 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

  • 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

  • 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

  • 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

  • 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

  • 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)&lt; 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  [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

  • 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

  • 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

  • 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

  • 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

  • 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 &quot;satellite core concept&quot; 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&#039;s future X-ray astronomy mission NeXT.

    DOI

  • 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 (&lt; 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

  • 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 &gt; 50 degrees and the expanding velocity of the shell as nu(shell) &gt; 1100 km s(-1).

    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

  • 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

  • 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 CdT