2021/06/25 更新

写真b

ヤマダ シンヤ
山田 真也
YAMADA Shinya
*大学が定期的に情報更新している項目(その他は、researchmapの登録情報を転載)
所属*
理学部 物理学科
理学研究科 物理学専攻博士課程後期課程
理学研究科 物理学専攻博士課程前期課程
職名*
准教授
学位
理学博士 ( 東京大学 )
研究テーマ*
  • 宇宙X線観測衛星の開発、X線観測装置の開発、およびそれを用いた高エネルギー宇宙物理学の研究を進めている。また、将来の精密X線分光観測に向けて、超電導検出器の開発と地上応用実験も進めており、宇宙の大規模構造のような大スケールの理解から身の回りの物質の理解まで、幅広く宇宙の成り立ちを解明することを目標としている。

  • 研究キーワード
  • 超伝導検出器

  • ブラックホール

  • X線検出器

  • X線天文学

  • 学内職務経歴*
    • 2020年4月 - 現在 
      理学部   物理学科   准教授
    • 2020年4月 - 現在 
      理学研究科   物理学専攻博士課程後期課程   准教授
    • 2020年4月 - 現在 
      理学研究科   物理学専攻博士課程前期課程   准教授
    プロフィール

    (2020年度より) 立教大学 理学部物理学科 准教授

    (2019年度まで) 首都大学東京 宇宙物理実験室 助教

     

    研究分野

    • 自然科学一般 / 素粒子、原子核、宇宙線、宇宙物理にする理論  / X-ray astronomy

    • 自然科学一般 / 天文学  / X線天文学

    経歴

    • 2020年4月 - 現在 
      立教大学   理学部 物理学科   准教授

      詳細を見る

    • 2014年4月 - 2020年3月 
      首都大学東京   理学部物理学科宇宙物理実験室   助教

      詳細を見る

    • 2011年4月 - 2014年3月 
      理化学研究所   玉川宇宙物理研究室   基礎科学特別研究員

      詳細を見る

    学歴

    • 2006年4月 - 2011年3月 
      東京大学   理学系研究科   物理学科

      詳細を見る

      国名: 日本国

      researchmap

    • 2002年4月 - 2006年3月 
      東京大学   理学部   物理学科

      詳細を見る

    論文

    • Transition-Edge Sensor Optimization for Hard X-ray Applications

      Daikang Yan, Joel C. Weber, Kelsey M. Morgan, Abigail L. Wessels, Douglas A. Bennett, Christine G. Pappas, John A. Mates, Johnathon D. Gard, Dan T. Becker, Joseph W. Fowler, Daniel S. Swetz, Dan R. Schmidt, Joel N. Ullom, Takuma Okumura, Tadaaki Isobe, Toshiyuki Azuma, Shinya Yamada, Shinji Okada, Tadashi Hashimoto, Nancy Paul, Guojie Bian, Paul Indelicato

      IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY31 ( 5 )   2021年8月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC  

      Arrays of superconducting transition-edge sensor (TES) microcalorimeters are attractive for someX-ray experiments where the combination of higher collection efficiency than crystal spectrometers and much better energy resolution than semiconductor detectors is enabling. For hard X-ray (>2 keV) applications, a TESis often integratedwith an extra absorber to extend its dynamic range, quantum efficiency and collecting area. For >100 keV applications, millimeter size absorbers have been manually attached to TES pixels after fabrication. At lower energies, the absorber size needs to be much smaller, because a large heat capacity degrades energy resolution. In that case, the absorber is directly electroplated or evaporated on the TES during the fabrication process. In this work, we present TES microcalorimeters optimized for the intermediate hard X-ray energy region (20 keV similar to 100 keV) that have thick absorbers directly deposited during the TES fabrication process. This microcalorimeter is designed to measure high-resolution muonic atom transition X-ray spectra as a method to study quantum electrodynamics (QED) effects. The absorber is comprised of evaporated gold and electroplated bismuth layers and is designed to optimize dynamic range, collecting efficiency, and energy resolution in the 20 keV to 45 keVenergy range. Aprototype with pure gold absorbers has been fabricated and characterized, in order to obtain a first experimental reference in the detector development process.

      DOI: 10.1109/TASC.2021.3059972

      researchmap

    • Broadband high-energy resolution hard x-ray spectroscopy using transition edge sensors at SPring-8

      Shinya Yamada, Yuto Ichinohe, Hideyuki Tatsuno, Ryota Hayakawa, Hirotaka Suda, Takaya Ohashi, Yoshitaka Ishisaki, Tomoya Uruga, Oki Sekizawa, Kiyofumi Nitta, Yoshio Takahashi, Takaaki Itai, Hiroki Suga, Makoto Nagasawa, Masato Tanaka, Minako Kurisu, Tadashi Hashimoto, Douglas Bennett, Ed Denison, William Bertrand Doriese, Malcolm Durkin, Joseph Fowler, Galen O’Neil, Kelsey Morgan, Dan Schmidt, Daniel Swetz, Joel Ullom, Leila Vale, Shinji Okada, Takuma Okumura, Toshiyuki Azuma, Toru Tamagawa, Tadaaki Isobe, Satoshi Kohjiro, Hirofumi Noda, Keigo Tanaka, Akimichi Taguchi, Yuki Imai, Kosuke Sato, Tasuku Hayashi, Teruhiko Kashiwabara, Kohei Sakata

      Review of Scientific Instruments   2021年1月1日

      詳細を見る

      掲載種別:研究論文(学術雑誌)  

      DOI: 10.1063/5.0020642

      researchmap

    • Low-noise microwave SQUID multiplexed readout of 38 x-ray transition-edge sensor microcalorimeters

      Y. Nakashima, F. Hirayama, S. Kohjiro, H. Yamamori, S. Nagasawa, A. Sato, S. Yamada, R. Hayakawa, N. Y. Yamasaki, K. Mitsuda, K. Nagayoshi, H. Akamatsu, L. Gottardi, E. Taralli, M. P. Bruijn, M. L. Ridder, J. R. Gao, J. W. A. den Herder

      Applied Physics Letters   2020年9月21日

      詳細を見る

      掲載種別:研究論文(学術雑誌)  

      DOI: 10.1063/5.0016333

      researchmap

    • Coevolution of the Technology on Transition-Edge-Sensor Spectrometer and Its Application to Fundamental Science 査読有り

      S. Yamada, H. Tatsuno, S. Okada, T. Hashimoto

      Journal of Low Temperature Physics200 ( 5-6 ) 418 - 427   2020年9月

      詳細を見る

      担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Springer Science and Business Media LLC  

      DOI: 10.1007/s10909-020-02441-2

      researchmap

      その他リンク: http://link.springer.com/article/10.1007/s10909-020-02441-2/fulltext.html

    • X-ray Spectroscopy of Muonic Atoms Isolated in Vacuum with Transition Edge Sensors 査読有り

      S. Okada, T. Azuma, D. A. Bennett, P. Caradonna, W. B. Doriese, M. S. Durkin, J. W. Fowler, J. D. Gard, T. Hashimoto, R. Hayakawa, G. C. Hilton, Y. Ichinohe, P. Indelicato, T. Isobe, S. Kanda, M. Katsuragawa, N. Kawamura, Y. Kino, Y. Miyake, K. M. Morgan, K. Ninomiya, H. Noda, G. C. O’Neil, T. Okumura, C. D. Reintsema, D. R. Schmidt, K. Shimomura, P. Strasser, D. S. Swetz, T. Takahashi, S. Takeda, S. Takeshita, H. Tatsuno, Y. Ueno, J. N. Ullom, S. Watanabe, S. Yamada

      Journal of Low Temperature Physics   2020年6月13日

      詳細を見る

      掲載種別:研究論文(学術雑誌)   出版者・発行元:Springer Science and Business Media LLC  

      DOI: 10.1007/s10909-020-02476-5

      researchmap

      その他リンク: http://link.springer.com/article/10.1007/s10909-020-02476-5/fulltext.html

    • Mitigating the Effects of Charged Particle Strikes on TES Arrays for Exotic Atom X-ray Experiments 査読有り

      H. Tatsuno, D. A. Bennett, W. B. Doriese, M. S. Durkin, J. W. Fowler, J. D. Gard, T. Hashimoto, R. Hayakawa, T. Hayashi, G. C. Hilton, Y. Ichinohe, H. Noda, G. C. O’Neil, S. Okada, C. D. Reintsema, D. R. Schmidt, D. S. Swetz, J. N. Ullom, S. Yamada

      Journal of Low Temperature Physics   2020年6月10日

      詳細を見る

      掲載種別:研究論文(学術雑誌)   出版者・発行元:Springer Science and Business Media LLC  

      DOI: 10.1007/s10909-020-02484-5

      researchmap

      その他リンク: http://link.springer.com/article/10.1007/s10909-020-02484-5/fulltext.html

    • High Energy Background Event Identification Using Local Group Trigger in a 240-pixel X-ray TES Array 査読有り

      S. Yamada, R. Hayakawa, H. Tatsuno, J. W. Fowler, D. S. Swetz, D. A. Bennett, M. Durkin, G. C. O’Neil, J. N. Ullom, W. B. Doriese, C. D. Reintsema, J. D. Gard, S. Okada, T. Hashimoto, Y. Ichinohe, H. Noda, T. Hayashi

      Journal of Low Temperature Physics   2020年5月29日

      詳細を見る

      掲載種別:研究論文(学術雑誌)   出版者・発行元:Springer Science and Business Media LLC  

      DOI: 10.1007/s10909-020-02468-5

      researchmap

      その他リンク: http://link.springer.com/article/10.1007/s10909-020-02468-5/fulltext.html

    • Integration of a TES-based X-ray spectrometer in a kaonic atom experiment 査読有り

      T. Hashimoto, D. A. Bennett, W. B. Doriese, M. S. Durkin, J. W. Fowler, J. D. Gard, R. Hayakawa, T. Hayashi, G. C. Hilton, Y. Ichinohe, S. Ishimoto, K. M. Morgan, H. Noda, G. C. O’Neil, S. Okada, C. D. Reintsema, D. R. Schmidt, S. Suzuki, D. S. Swetz, H. Tatsuno, J. N. Ullom, S. Yamada

      Journal of Low Temperature Physics199 ( 3-4 ) 1018 - 1026   2020年5月

      詳細を見る

      掲載種別:研究論文(学術雑誌)   出版者・発行元:Springer Science and Business Media LLC  

      DOI: 10.1007/s10909-020-02434-1

      researchmap

      その他リンク: http://link.springer.com/article/10.1007/s10909-020-02434-1/fulltext.html

    • Waveform Analysis of a 240-Pixel TES Array for X-Rays and Charged Particles Using a Function of Triggering Neighboring Pixels 査読有り

      R. Hayakawa, S. Yamada, H. Tatsuno, J. W. Fowler, D. S. Swetz, D. A. Bennett, M. Durkin, G. C. O’Neil, J. N. Ullom, W. B. Doriese, C. D. Reintsema, J. D. Gard, S. Okada, T. Hashimoto, Y. Ichinohe, H. Noda, T. Hayashi

      Journal of Low Temperature Physics   2020年4月13日

      詳細を見る

      掲載種別:研究論文(学術雑誌)   出版者・発行元:Springer Science and Business Media LLC  

      DOI: 10.1007/s10909-020-02449-8

      researchmap

      その他リンク: http://link.springer.com/article/10.1007/s10909-020-02449-8/fulltext.html

    • Poisson vs. Gaussian statistics for sparse X-ray data: Application to the soft X-ray spectrometer

      Shinya Yamada, Magnus Axelsson, Yoshitaka Ishisaki, Saori Konami, Nozomi Takemura, Richard L. Kelley, Caroline A. Kilbourne, Maurice A. Leutenegger, F. Scott Porter, Megan E. Eckart, Andrew Szymkowiak

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN71 ( 4 )   2019年8月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      Reliable results when fitting X-ray data require proper consideration of the statistics involved. We probe the impact of Gaussian versus Poisson statistics at low count levels using both the standard chi(2) method and maximum likelihood based on Poisson (C) statistics. The difference is studied and quantified through simulated spectra with known properties. We then test the results through analysis of Mn K alpha calibration data taken with the flight spare microcalorimeter for the Hitomi soft X-ray spectrometer. Through comparison with simulations, our results show that the chi(2) method tends to give overly optimistic estimates of the detector energy resolution, in particular when there are few counts. Given an energy resolution of similar to 5eV and a line with about 100 photons, the line width becomes similar to 10% lower in the chi(2) method than in Poisson statistics. This is a consequence of the uncertainties being dominated by counting statistics, and therefore highlights the need to choose the appropriate fit statistic.

      DOI: 10.1093/pasj/psz053

      researchmap

    • Study of Surface Roughness Effect on Super–Normal Transition of Ti/Au Transition Edge Sensor Calorimeters

      K. Kengo, Y. Ezoe, S. Kitazawa, R. Hayakawa, K. Nunomura, T. Ohashi, Y. Ishisaki, S. Yamada, M. Hidaka, T. Satoh, K. Mitsuda

      Journal of Low Temperature Physics193   1 - 7   2018年6月26日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)  

      © 2018, Springer Science+Business Media, LLC, part of Springer Nature. We are developing transition edge sensor (TES) X-ray microcalorimeters for the future Japanese mission DIOS. It adopts microstrip readout wiring for low pixel-to-pixel crosstalk. In past samples, TES films composed of Ti and Au have not shown proper super–normal transition when it is deposited on the wiring. Assuming that surface roughness of the substrate can influence the transition, we reduced the surface roughness of the underneath layer before deposition of the TES film by using chemical mechanical polishing. We then found that the substrate becomes much smoother with a roughness of <1 nm rms and the TES film shows a proper transition.

      DOI: 10.1007/s10909-018-1995-z

      Scopus

      researchmap

    • Hitomi X-ray observation of the pulsar wind nebula G21.5-0.9 査読有り

      Hitomi Collaboration, Aharonian F, Akamatsu H, Akimoto F, Allen S. et al, Yamada S, th author out, authors

      Publications of the Astronomical Society of Japanvol.70   38   2018年6月

      詳細を見る

    • Super DIOS: Future X-ray Spectroscopic Mission to Search for Dark Baryons 査読有り

      S. Yamada, T. Ohashi, Y. Ishisaki, Y. Ezoe, Y. Ichinohe, S. Kitazawa, K. Kosaka, R. Hayakawa, K. Nunomura, K. Mitsuda, N. Y. Yamasaki, T. Kikuchi, T. Hayashi, H. Muramatsu, Y. Nakashima, Y. Tawara, I. Mitsuishi, Y. Babazaki, D. Seki, K. Otsuka, M. Ishihara, K. Osato, N. Ota, M. Tomariguchi, D. Nagai, E. Lau, K. Sato, the DIOS team

      Journal of Low Temperature Physics   1 - 8   2018年4月24日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Springer New York LLC  

      The updated program of the future Japanese X-ray satellite mission Diffuse Intergalactic Oxygen Surveyor (DIOS), called as Super DIOS, is planned to search for dark baryons in the form of warm–hot intergalactic medium (WHIM) with high-resolution X-ray spectroscopy. The mission will detect redshifted emission lines from OVII, OVIII and other ions, leading to an overall understanding of the physical nature and spatial distribution of dark baryons as a function of cosmological timescale. We have started the conceptual design of the satellite and onboard instruments, focusing on the era of 2030s. The major change will be an improved angular resolution of the X-ray telescope. Super DIOS will have a 10-arcsec resolution, which is an improvement by a factor of about 20 over DIOS. With this resolution, most of the contaminating X-ray sources will be separated, and the level of the diffuse X-ray background will be much reduced after subtraction of point sources. This will give us higher sensitivity to map out the WHIM in emission.

      DOI: 10.1007/s10909-018-1918-z

      Scopus

      researchmap

    • Neural network-based preprocessing to estimate the parameters of the X-ray emission of a single-temperature thermal plasma 査読有り

      Y. Ichinohe, S. Yamada, N. Miyazaki, S. Saito

      Monthly Notices of the Royal Astronomical Society475 ( 4 ) 4739 - 4744   2018年4月21日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Oxford University Press  

      We present data preprocessing based on an artificial neural network to estimate the parameters of the X-ray emission spectra of a single-temperature thermal plasma. The method finds appropriate parameters close to the global optimum. The neural network is designed to learn the parameters of the thermal plasma (temperature, abundance, normalization and redshift) of the input spectra. After training using 9000 simulated X-ray spectra, the network has grown to predict all the unknown parameters with uncertainties of about a fewper cent. The performance dependence on the network structure has been studied. We applied the neural network to an actual high-resolution spectrum obtained with Hitomi. The predicted plasma parameters agree with the known best-fitting parameters of the Perseus cluster within uncertainties of ≲10 per cent. The result shows that neural networks trained by simulated data might possibly be used to extract a feature built in the data. This would reduce human-intensive preprocessing costs before detailed spectral analysis, and would help us make the best use of the large quantities of spectral data that will be available in the coming decades.

      DOI: 10.1093/mnras/sty161

      Scopus

      researchmap

    • Resolve Instrument on X-ray Astronomy Recovery Mission (XARM) 査読有り

      Y. Ishisaki, Y. Ezoe, S. Yamada, Y. Ichinohe, R. Fujimoto, Y. Takei, S. Yasuda, M. Ishida, N. Y. Yamasaki, Y. Maeda, M. Tsujimoto, R. Iizuka, S. Koyama, H. Noda, T. Tamagawa, M. Sawada, K. Sato, S. Kitamoto, A. Hoshino, G. V. Brown, M. E. Eckart, T. Hayashi, R. L. Kelley, C. A. Kilbourne, M. A. Leutenegger, H. Mori, T. Okajima, F. S. Porter, Y. Soong, D. McCammon, A. E. Szymkowiak, The XARM Resolve Team

      Journal of Low Temperature Physics   1 - 5   2018年4月19日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Springer New York LLC  

      The X-ray Astronomy Recovery Mission (XARM) is a recovery mission of ASTRO-H/Hitomi, which is expected to be launched in Japanese Fiscal Year of 2020 at the earliest. The Resolve instrument on XARM consists of an array of 6 × 6 silicon-thermistor microcalorimeters cooled down to 50 mK and a high-throughput X-ray mirror assembly with the focal length of 5.6 m. Hitomi was launched into orbit in February 2016 and observed several celestial objects, although the operation of Hitomi was terminated in April 2016. The soft X-ray spectrometer (SXS) on Hitomi demonstrated high-resolution X-ray spectroscopy of ~ 5 eV FWHM in orbit for most of the pixels. The Resolve instrument is planned to mostly be a copy of the Hitomi SXS and soft X-ray telescope designs, though several changes are planned based on the lessons learned from Hitomi. We report a brief summary of the SXS performance and the status of the Resolve instrument.

      DOI: 10.1007/s10909-018-1913-4

      Scopus

      researchmap

    • Ground calibration of the Astro-H (Hitomi) soft x-ray spectrometer 査読有り

      Megan E. Eckart, Joseph S. Adams, Kevin R. Boyce, Gregory V. Brown, Meng P. Chiao, Ryuichi Fujimoto, Daniel Haas, Jan-Willem Den Herder, Akio Hoshino, Yoshitaka Ishisaki, Caroline A. Kilbourne, Shunji Kitamoto, Maurice A. Leutenegger, Dan McCammon, Kazuhisa Mitsuda, F. Scott Porter, Kosuke Sato, Makoto Sawada, Hiromi Seta, Gary A. Sneiderman, Andrew E. Szymkowiak, Yoh Takei, Makoto S. Tashiro, Masahiro Tsujimoto, Cor P. De Vries, Tomomi Watanabe, Shinya Yamada, Noriko Y. Yamasaki

      Journal of Astronomical Telescopes, Instruments, and Systems4 ( 2 ) 021406   2018年4月1日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPIE  

      The Astro-H (Hitomi) Soft X-ray Spectrometer (SXS) was a pioneering imaging x-ray spectrometer with 5 eV energy resolution at 6 keV. The instrument used a microcalorimeter array at the focus of a high-Throughput soft x-ray telescope to enable high-resolution nondispersive spectroscopy in the soft x-ray waveband (0.3 to 12 keV). We present the suite of ground calibration measurements acquired from 2012 to 2015, including characterization of the detector system, anti-coincidence detector, optical blocking filters, and filter-wheel filters. The calibration of the 36-pixel silicon thermistor microcalorimeter array includes parameterizations of the energy gain scale and line-spread function for each event grade over a range of instrument operating conditions, as well as quantum efficiency measurements. The x-ray transmission of the set of five Al/polyimide thin-film optical blocking filters mounted inside the SXS dewar has been modeled based on measurements at synchrotron beamlines, including with high spectral resolution at the C, N, O, and Al K-edges. In addition, we present the x-ray transmission of the dewar gate valve and of the filters mounted on the SXS filter wheel (external to the dewar), including beryllium, polyimide, and neutral density filters.

      DOI: 10.1117/1.JATIS.4.2.021406

      Scopus

      researchmap

    • HITOMI (ASTRO-H) X-ray astronomy satellite 査読有り

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

      Journal of Astronomical Telescopes, Instruments, and Systems4 ( 2 ) 021402   2018年4月

      詳細を見る

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

      DOI: 10.1117/1.JATIS.4.2.021402

      Scopus

      researchmap

    • In-Orbit Performance of the Digital Electronics for the X-Ray Microcalorimeter Onboard the Hitomi Satellite 査読有り

      M. Tsujimoto, M. S. Tashiro, Y. Ishisaki, S. Yamada, H. Seta, K. Mitsuda, K. R. Boyce, M. E. Eckart, C. A. Kilbourne, M. A. Leutenegger, F. S. Porter, R. L. Kelley

      Journal of Low Temperature Physics   1 - 7   2018年3月8日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Springer New York LLC  

      The pulse shape processor is the onboard digital electronics unit of the X-ray microcalorimeter instrument—the soft X-ray spectrometer—onboard the Hitomi satellite. It processes X-ray events using the optimum filtering with limited resources. It was operated for 36 days in orbit continuously without issues and met the requirement of processing a (Formula presented.) event rate during the observation of bright sources. Here, we present the results obtained in orbit, focusing on its performance as the onboard digital signal processing unit of an X-ray microcalorimeter.

      DOI: 10.1007/s10909-018-1861-z

      Scopus

      researchmap

    • Hitomi X-ray studies of giant radio pulses from the Crab pulsar 査読有り

      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 Japan70 ( 2 ) 15   2018年3月1日

      詳細を見る

      掲載種別:研究論文(学術雑誌)  

      © The Author(s) 2017. Published by Oxford University Press on behalf of the Astronomical Society of Japan. 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.

      DOI: 10.1093/pasj/psx083

      Scopus

      researchmap

    • Atmospheric gas dynamics in the Perseus cluster observed with Hitomi 査読有り

      Hitomi Collaboration, Aharonian F, Akamatsu H, Akimoto F, Allen S. et al, Yamada S, th author out, authors

      Publications of the Astronomical Society of Japanvol.70   9   2018年3月

      詳細を見る

    • Atomic data and spectral modeling constraints from high-resolution X-ray observations of the Perseus cluster with Hitomi 査読有り

      Hitomi Collaboration, Aharonian F, Akamatsu H, Akimoto F, Allen S. et al, Yamada S, th author out, authors

      Publications of the Astronomical Society of Japanvol.70   12   2018年3月

      詳細を見る

    • Glimpse of the highly obscured HMXB IGR J16318-4848 with Hitomi 査読有り

      Hitomi Collaboration, Aharonian F, Akamatsu H, Akimoto F, Allen S. et al, Yamada S, th author out, authors

      Publications of the Astronomical Society of Japanvol.70   17   2018年3月

      詳細を見る

    • Hitomi observation of radio galaxy NGC 1275: The first X-ray microcalorimeter spectroscopy of Fe-K\ensuremath\alpha line emission from an active galactic nucleus 査読有り

      Hitomi Collaboration, Aharonian F, Akamatsu H, Akimoto F, Allen S. et al, Yamada S, th author out, authors

      Publications of the Astronomical Society of Japanvol.70   13   2018年3月

      詳細を見る

    • Hitomi observations of the LMC SNR N 132 D: Highly redshifted X-ray emission from iron ejecta 査読有り

      Hitomi Collaboration, Aharonian F, Akamatsu H, Akimoto F, Allen S. et al, Yamada S, th author out, authors

      Publications of the Astronomical Society of Japanvol.70   16   2018年3月

      詳細を見る

    • In-flight calibration of Hitomi Soft X-ray Spectrometer. (1) Background 査読有り

      Kilbourne C, Sawada M, Tsujimoto M, Angellini L, Boyce K. et al, Yamada S, th author out o, authors

      Publications of the Astronomical Society of Japanvol.70   18   2018年3月

      詳細を見る

    • Measurements of resonant scattering in the Perseus Cluster core with Hitomi SXS 査読有り

      Hitomi Collaboration, Aharonian F, Akamatsu H, Akimoto F, Allen S. et al, Yamada S, th author out, authors

      Publications of the Astronomical Society of Japanvol.70   10   2018年3月

      詳細を見る

    • Search for thermal X-ray features from the Crab nebula with the Hitomi soft X-ray spectrometer 査読有り

      Hitomi Collaboration, Aharonian F, Akamatsu H, Akimoto F, Allen S. et al, Yamada S, th author out, authors

      Publications of the Astronomical Society of Japanvol.70   14   2018年3月

      詳細を見る

    • Temperature structure in the Perseus cluster core observed with Hitomi 査読有り

      Hitomi Collaboration, Aharonian F, Akamatsu H, Akimoto F, Allen S. et al, Yamada S, th author out, authors

      Publications of the Astronomical Society of Japanvol.70   11   2018年3月

      詳細を見る

    • In-flight performance of the soft x-ray spectrometer detector system on Astro-H 査読有り

      Frederick S. Porter, Kevin R. Boyce, Meng P. Chiao, Megan E. Eckart, Ryuichi Fujimoto, Yoshitaka Ishisaki, Caroline Anne Kilbourne, Maurice A. Leutenegger, Daniel McCammon, Kazuhisa Mitsuda, Kosuke Sato, Hiromi Seta, Makoto Sawada, Gary A. Sneiderman, Andrew E. Szymkowiak, Yoh Takei, Makoto S. Tashiro, Masahiro Tsujimoto, Tomomi Watanabe, Shinya Yamada

      Journal of Astronomical Telescopes, Instruments, and Systems4 ( 1 ) 011217   2018年1月1日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPIE  

      The soft x-ray spectrometer (SXS) instrument was launched aboard the Astro-H (Hitomi) observatory on February 17, 2016. The SXS is based on a high-sensitivity x-ray calorimeter detector system that has been successfully deployed in many ground and suborbital spectrometers. The instrument was to provide essential diagnostics for nearly every class of x-ray emitting objects from the atmosphere of Jupiter to the outskirts of galaxy clusters, without degradation for spatially extended objects. The SXS detector system consisted of a 36-pixel cryogenic microcalorimeter array operated at a heat sink temperature of 50 mK. In preflight testing, the detector system demonstrated a resolving power of better than 1300 at 6 keV with a simultaneous bandpass from below 0.3 keV to above 12 keV with a timing precision better than 100 μs. In addition, a solid-state anticoincidence detector was placed directly behind the detector array for background suppression. The detector error budget included the measured interference from the SXS cooling system and the spacecraft. Additional margin for on-orbit gain stability and on-orbit spacecraft interference were also included predicting an on-orbit performance that meets or exceeds the 7-eV FWHM at 6-keV requirement. The actual on-orbit spectral resolution was better than 5 eV FWHM at 6 keV, easily satisfying the instrument requirement. Here, we discuss the actual on-orbit performance of the SXS detector system and compare this to performance in preflight testing and the on-orbit predictions. We will also discuss the on-orbit gain stability, additional on-orbit interference, and measurements of the on-orbit background.

      DOI: 10.1117/1.JATIS.4.1.011218

      Scopus

      researchmap

    • In-flight performance of the soft x-ray spectrometer detector system on Astro-H 査読有り

      Frederick S. Porter, Kevin R. Boyce, Meng P. Chiao, Megan E. Eckart, Ryuichi Fujimoto, Yoshitaka Ishisaki, Caroline Anne Kilbourne, Maurice A. Leutenegger, Daniel McCammon, Kazuhisa Mitsuda, Kosuke Sato, Hiromi Seta, Makoto Sawada, Gary A. Sneiderman, Andrew E. Szymkowiak, Yoh Takei, Makoto S. Tashiro, Masahiro Tsujimoto, Tomomi Watanabe, Shinya Yamada

      Journal of Astronomical Telescopes, Instruments, and Systems4 ( 1 ) 011218   2018年1月1日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPIE  

      The soft x-ray spectrometer (SXS) instrument was launched aboard the Astro-H (Hitomi) observatory on February 17, 2016. The SXS is based on a high-sensitivity x-ray calorimeter detector system that has been successfully deployed in many ground and suborbital spectrometers. The instrument was to provide essential diagnostics for nearly every class of x-ray emitting objects from the atmosphere of Jupiter to the outskirts of galaxy clusters, without degradation for spatially extended objects. The SXS detector system consisted of a 36-pixel cryogenic microcalorimeter array operated at a heat sink temperature of 50 mK. In preflight testing, the detector system demonstrated a resolving power of better than 1300 at 6 keV with a simultaneous bandpass from below 0.3 keV to above 12 keV with a timing precision better than 100 μs. In addition, a solid-state anticoincidence detector was placed directly behind the detector array for background suppression. The detector error budget included the measured interference from the SXS cooling system and the spacecraft. Additional margin for on-orbit gain stability and on-orbit spacecraft interference were also included predicting an on-orbit performance that meets or exceeds the 7-eV FWHM at 6-keV requirement. The actual on-orbit spectral resolution was better than 5 eV FWHM at 6 keV, easily satisfying the instrument requirement. Here, we discuss the actual on-orbit performance of the SXS detector system and compare this to performance in preflight testing and the on-orbit predictions. We will also discuss the on-orbit gain stability, additional on-orbit interference, and measurements of the on-orbit background.

      DOI: 10.1117/1.JATIS.4.1.011218

      Scopus

      researchmap

    • In-orbit operation of the soft x-ray spectrometer onboard the Hitomi satellite 査読有り

      Masahiro Tsujimoto, Kazuhisa Mitsuda, Richard L. Kelley, Jan-Willem Den Herder, Thomas G. Bialas, Kevin R. Boyce, Meng P. Chiao, Cor P. De Vries, Michael J. Dipirro, Megan E. Eckart, Yuichiro Ezoe, Ryuichi Fujimoto, Akio Hoshino, Kumi Ishikawa, Yoshitaka Ishisaki, Caroline A. Kilbourne, Shu Koyama, Maurice A. Leutenegger, Candace M. Masters, Ikuyuki Mitsuishi, Hirofumi Noda, Takashi Okajima, Atsushi Okamoto, Frederic S. Porter, Kosuke Sato, Yohichi Sato, Joseph C. Savinell, Makoto Sawada, Hiromi Seta, Peter J. Shirron, Gary A. Sneiderman, Yoh Takei, Toru Tamagawa, Makoto S. Tashiro, Tomomi Watanabe, Shinya Yamada, Noriko Y. Yamasaki, Yoichi Yatsu

      Journal of Astronomical Telescopes, Instruments, and Systems4 ( 1 ) 011205   2018年1月1日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPIE  

      We summarize all of the in-orbit operations of the soft x-ray spectrometer (SXS) onboard the ASTRO-H (Hitomi) satellite. The satellite was launched on February 17, 2016, and the communication with the satellite ceased on March 26, 2016. The SXS was still in the commissioning phase, in which the set-ups were progressively changed. This paper is intended to serve as a concise reference of the events in orbit in order to properly interpret the SXS data taken during its short lifetime and as a test case for planning the in-orbit operation for future microcalorimeter missions.

      DOI: 10.1117/1.JATIS.4.1.011205

      Scopus

      researchmap

    • Performance of the helium dewar and the cryocoolers of the Hitomi soft x-ray spectrometer 査読有り

      Ryuichi Fujimoto, Yoh Takei, Kazuhisa Mitsuda, Noriko Y. Yamasaki, Masahiro Tsujimoto, Shu Koyama, Kumi Ishikawa, Hiroyuki Sugita, Yoichi Sato, Keisuke Shinozaki, Atsushi Okamoto, Shunji Kitamoto, Akio Hoshino, Kosuke Sato, Yuichiro Ezoe, Yoshitaka Ishisaki, Shinya Yamada, Hiromi Seta, Takaya Ohashi, Toru Tamagawa, Hirofumi Noda, Makoto Sawada, Makoto Tashiro, Yoichi Yatsu, Ikuyuki Mitsuishi, Kenichi Kanao, Seiji Yoshida, Mikio Miyaoka, Shoji Tsunematsu, Kiyomi Otsuka, Katsuhiro Narasaki, Michael J. DiPirro, Peter J. Shirron, Gary A. Sneiderman, Caroline A. Kilbourne, Frederick Scott Porter, Meng P. Chiao, Megan E. Eckart

      Journal of Astronomical Telescopes, Instruments, and Systems4 ( 1 ) 011208   2018年1月1日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPIE  

      The soft x-ray spectrometer (SXS) was a cryogenic high-resolution x-ray spectrometer onboard the Hitomi (ASTRO-H) satellite that achieved energy resolution of 5 eV at 6 keV, by operating the detector array at 50 mK using an adiabatic demagnetization refrigerator (ADR). The cooling chain from room temperature to the ADR heat sink was composed of two-stage Stirling cryocoolers, a 4He Joule-Thomson cryocooler, and superfluid liquid helium and was installed in a dewar. It was designed to achieve a helium lifetime of more than 3 years with a minimum of 30 L. The satellite was launched on February 17, 2016, and the SXS worked perfectly in orbit, until March 26 when the satellite lost its function. It was demonstrated that the heat load on the helium tank was about 0.7 mW, which would have satisfied the lifetime requirement. This paper describes the design, results of ground performance tests, prelaunch operations, and initial operation and performance in orbit of the flight dewar and the cryocoolers.

      DOI: 10.1117/1.JATIS.4.1.011208

      Scopus

      researchmap

    • Vibration isolation system for cryocoolers of soft x-ray spectrometer on-board ASTRO-H (Hitomi) 査読有り

      Yoh Takei, Susumu Yasuda, Kosei Ishimura, Naoko Iwata, Atsushi Okamoto, Yoichi Sato, Mina Ogawa, Makoto Sawada, Taro Kawano, Shingo Obara, Chikara Natsukari, Atsushi Wada, Shinya Yamada, Ryuichi Fujimoto, Motohide Kokubun, Noriko Y. Yamasaki, Hiroyuki Sugita, Kenji Minesugi, Yasuo Nakamura, Kazuhisa Mitsuda, Tadayuki Takahashi, Seiji Yoshida, Shoji Tsunematsu, Kenichi Kanao, Katsuhiro Narasaki, Kiyomi Otsuka, F. Scott Porter, Caroline A. Kilbourne, Meng P. Chiao, Megan E. Eckart, Gary A. Sneiderman, James T. Pontius, Dan McCammon, Paul Wilke, John Basile

      Journal of Astronomical Telescopes, Instruments, and Systems4 ( 1 ) 011216   2018年1月1日

      詳細を見る

      掲載種別:研究論文(学術雑誌)  

      © The Authors 2018. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI. The soft x-ray spectrometer (SXS) onboard ASTRO-H (named Hitomi after launch) is a microcalorimeter-type spectrometer, installed in a dewar to be cooled at 50 mK. The energy resolution of the SXS engineering model suffered from microvibration from cryocoolers mounted on the dewar. This is mitigated for the flight model (FM) by introducing vibration isolation systems between the cryocoolers and the dewar. The detector performance of the FM was verified before launch of the spacecraft in both ambient condition and thermal-vacuum condition, showing no detectable degradation in energy resolution. The in-orbit detector spectral performance and cryocooler cooling performance were also consistent with that on ground, indicating that the cryocoolers were not damaged by launch environment. The design and performance of the vibration isolation system along with the mechanism of how the microvibration could degrade the cryogenic detector is shown. Lessons learned from the development to mitigate unexpected issues are also described.

      DOI: 10.1117/1.JATIS.4.1.011216

      Scopus

      researchmap

    • Solar abundance ratios of the iron-peak elements in the Perseus cluster 査読有り

      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

      NATURE551 ( 7681 ) 478 - +   2017年11月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:NATURE PUBLISHING GROUP  

      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: 10.1038/nature24301

      researchmap

    • A Semi-analytical Model for Wind-fed Black Hole High-mass X-Ray Binaries: State Transition Triggered by Magnetic Fields from the Companion Star 査読有り

      Kentaro Yaji, Shinya Yamada, Kuniaki Masai

      ASTROPHYSICAL JOURNAL847 ( 2 ) 129   2017年10月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      We propose a mechanism of state transition in wind-fed black hole (BH) binaries (high-mass X-ray binaries) such as Cyg X-1 and LMC X-1. Modeling a line-driven stellar wind from the companion by two-dimensional hydrodynamical calculations, we investigate the processes of wind capture by, and accretion onto, the BH. We assume that the wind acceleration is terminated at the He II ionization front because ions responsible for line-driven acceleration are ionized within the front, i.e., the He III region. It is found that the mass accretion rate inferred from the luminosity is remarkably smaller than the capture rate. Considering the difference, we construct a model for the state transition based on the accretion flow being controlled by magnetorotational instability. The outer flow is torus-like, and plays an important role to trigger the transition. The model can explain why state transition does occur in Cyg X-1, while not in LMC X-1. Cyg X-1 exhibits a relatively low luminosity, and then the He II ionization front is located and can move between the companion and BH, depending on its ionizing photon flux. On the other hand, LMC X-1 exhibits too high luminosity for the front to move considerably; the front is too close to the companion atmosphere. The model also predicts that each state of high-soft or low-hard would last fairly long because the luminosity depends weakly on the wind velocity. In the context of the model, the state transition is triggered by a fluctuation of the magnetic field when its amplitude becomes comparable to the field strength in the torus-like outer flow.

      DOI: 10.3847/1538-4357/aa88d3

      researchmap

    • Black hole spin of Cygnus X-1 determined from the softest state ever observed 査読有り

      Takafumi Kawano, Chris Done, Shin'ya Yamada, Hiromitsu Takahashi, Magnus Axelsson, Yasushi Fukazawa

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN69 ( 2 ) 36   2017年4月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      We show the softest ever spectrum from Cyg X-1, detected in 2013 with Suzaku. This has the weakest high-energy Compton tail ever seen from this object, so should give the cleanest view of the underlying disk spectrum, and hence the best determination of black hole spin from disk continuum fitting. Using the standard model of a disk with simple non-thermal Comptonization to produce the weak high-energy tail gives a highspin black hole. However, we get a significantly better fit by including an additional, low-temperature thermal Comptonization component, which allows a much lower black hole spin. Corroboration of the existence of an additional Compton component comes from the frequency-dependent hard lags seen in the rapid variability in archival high/soft state data. These cannot be explained if the continuum is a single non-thermal Comptonization component, but are instead consistent with a radially stratified, multi-zone Comptonization spectrum, where the spectrum is softer further from the black hole. A complex multi-zone Comptonization continuum is required to explain both spectra and timing together, and this has an impact on the derived black hole spin.

      DOI: 10.1093/pasj/psx009

      researchmap

    • Hitomi Constraints on the 3.5 keV Line in the Perseus Galaxy Cluster 査読有り

      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 LETTERS837 ( 1 ) L15   2017年3月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      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: 10.3847/2041-8213/aa61fa

      researchmap

    • Study of the time-series of microvariability in Kepler blazar W2R 1926+42 査読有り

      Mahito Sasada, Shin Mineshige, Shinya Yamada, Hitoshi Negoro

      Galaxies5 ( 1 ) 13   2017年2月8日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:MDPI AG  

      One of the remarkable features of blazars is violent variability over a wide wavelength range. The variation mechanism causing the observed complex behavior is still under debate. The variability timescales range from less than a day to decades. Variation on timescales less than a day is known as "microvariability." Such short-term variations can provide insights regarding the origin of the variability after they are distinguished from longer-term variational components. We select about 195 microvariability events from the continuous light curve of blazar W2R 1926+42 with 1-min time resolution obtained by the Kepler spacecraft, and estimate the timescale and amplitude of each event. The rise and decay timescales of the events reveal random variations over short timescales less than a day, but they indicate systematic variations on timescales longer than several days. This result implies that the events are not independent, but rather mutually correlated.

      DOI: 10.3390/galaxies5010013

      Scopus

      researchmap

    • Understanding the general feature of microvariability in Kepler blazar W2R 1926+42 査読有り

      Mahito Sasada, Shin Mineshige, Shinya Yamada, Hitoshi Negoro

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN69 ( 1 ) 15   2017年2月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      We analyze the Kepler monitoring light curve of a blazar W2R 1926+42 to examine features of microvariability by means of the "shot analysis" technique. We select 195 intra-day, flare-like variations (shots) for the continuous light curve of Quarter 14 with a duration of 100 d. In the application of the shot analysis, an averaged profile of variations is assumed to converge with a universal profile which reflects a physical mechanism generating themicrovariability in a blazar jet, although light-variation profiles of selected shots show a variety. A mean profile, which is obtained by aligning the peaks of the 195 shots, is composed of a spiky-shaped shot component at +/-0.1 d (with respect to the time of the peak), and two slow varying components ranging from -0.50 d to -0.15 d and from 0.10 d to 0.45 d of the peak time. The former spiky feature is well represented by an exponential rise of 0.043 +/- 0.001 d and an exponential decay of 0.061 +/- 0.002 d. These timescales are consistent with that corresponding to a break frequency of a power spectrum density calculated from the obtained light curve. After verification with the Monte Carlo method, the exponential shape, but not the observed asymmetry, of the shot component can be explained by noise variation. The asymmetry is difficult to explain through a geometrical effect (i.e., changes of the geometry of the emitting region), but is more likely to be caused by the production and dissipation of high-energy accelerated particles in the jet. Additionally, the durations of the detected shots show a systematic variation with a dispersion caused by a statistical randomness. A comparison with the variability of Cygnus X-1 is also briefly discussed.

      DOI: 10.1093/pasj/psw119

      researchmap

    • Beamline test of a transition-edge-sensor spectrometer in preparation for kaonic-atom measurements 査読有り

      Hashimoto, T., Bazzi, M., Bennett, D.A., Berucci, C., Bosnar, D., Curceanu, C., Doriese, W.B., Fowler, J.W., Fujioka, H., Guaraldo, C., Parnefjord Gustafsson, F., Hayakawa, R., Hayano, R.S., Hays-Wehle, J.P., Hilton, G.C., Hiraiwa, T., Ichinohe, Y., Iio, M., Iliescu, M., Ishimoto, S., Ishisaki, Y., Itahashi, K., Iwasaki, M., Ma, Y., Noda, H., Noumi, H., O'Neil, G.C., Ohnishi, H., Okada, S., Outa, H., Piscicchia, K., Reintsema, C.D., Sada, Y., Sakuma, F., Sato, M., Schmidt, D.R., Scordo, A., Sekimoto, M., Shi, H., Sirghi, D., Sirghi, F., Suzuki, K., Swetz, D.S., Tanida, K., Tatsuno, H., Tokuda, M., Uhlig, J., Ullom, J.N., Yamada, S., Yamazaki, T., Zmeskal, J.

      IEEE Transactions on Applied Superconductivity27 ( 4 )   2017年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)  

      DOI: 10.1109/TASC.2016.2646374

      Scopus

      researchmap

    • The New Primary X-ray Spectral Component of IC4329A Confirmed with Suzaku and NuSTAR

      Miyake K, Noda H, Yamada S

      Proceedings of 7 years of MAXI: monitoring X-ray Transients 2017   229   2017年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

      researchmap

    • Matched-filtering line search methods applied to Suzaku data 査読有り

      Naoto Miyazaki, Shin'ya Yamada, Teruaki Enoto, Magnus Axelsson, Takaya Ohashi

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN68 ( 6 ) 100   2016年12月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      A detailed search for emission and absorption lines and an assessment of their upper limits are performed for Suzaku data. The method utilizes a matched-filtering approach to maximize the signal-to-noise ratio for a given energy resolution, which could be applicable to many types of line search. We first applied it to well-known active galactic nuclei spectra that have been reported to have ultra-fast outflows, and find that our results are consistent with previous findings at the similar to 3 sigma level. We proceeded to search for emission and absorption features in two bright magnetars 4U 0142+61 and 1RXS J1708-4009, applying the filtering method to Suzaku data. We found that neither source showed any significant indication of line features, even using long-term Suzaku observations or dividing their spectra into spin phases. The upper limits on the equivalent width of emission/absorption lines are constrained to be a few eV at similar to 1 keV and a few hundreds of eV at similar to 10 keV. This strengthens previous reports that persistently bright magnetars do not show proton cyclotron absorption features in soft X-rays and, even if they exist, they would be broadened or much weaker than below the detection limit of X-ray CCD.

      DOI: 10.1093/pasj/psw091

      researchmap

    • X-RAY and OPTICAL CORRELATION of TYPE i SEYFERT NGC 3516 STUDIED with SUZAKU and JAPANESE GROUND-BASED TELESCOPES 査読有り

      Hirofumi Noda, Takeo Minezaki, Makoto Watanabe, Mitsuru Kokubo, Kenji Kawaguchi, Ryosuke Itoh, Kumiko Morihana, Yoshihiko Saito, Hikaru Nakao, Masataka Imai, Yuki Moritani, Katsutoshi Takaki, Miho Kawabata, Tatsuya Nakaoka, Makoto Uemura, Koji Kawabata, Michitoshi Yoshida, Akira Arai, Yuhei Takagi, Tomoki Morokuma, Mamoru Doi, Yoichi Itoh, Shin'Ya Yamada, Kazuhiro Nakazawa, Yasushi Fukazawa, Kazuo Makishima

      Astrophysical Journal828 ( 2 ) 78   2016年9月10日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Institute of Physics Publishing  

      From 2013 April to 2014 April, we performed X-ray and optical simultaneous monitoring of the type 1.5 Seyfert galaxy NGC 3516. We employed Suzaku and five Japanese ground-based telescopes - the Pirka, Kiso Schmidt, Nayuta, MITSuME, and the Kanata telescopes. The Suzaku observations were conducted seven times with various intervals ranging from days or weeks to months, with an exposure of ∼50 ks each. The optical B-band observations not only covered those of Suzaku almost simultaneously, but also followed the source as frequently as possible. As a result, NGC 3516 was found in its faint phase with a 2-10 keV flux of 0.21-2.70 �10-11 erg s-1 cm-2. The 2-45 keV X-ray spectra were composed of a dominant variable hard power-law (PL) continuum with a photon index of ∼1.7 and a non-relativistic reflection component with a prominent Fe-Kα emission line. Producing the B-band light curve by differential image photometry, we found that the B-band flux changed by ∼2.7 �10-11 erg s-1 cm-2, which is comparable to the X-ray variation, and we detected a significant flux correlation between the hard PL component in X-rays and the B-band radiation, for the first time in NGC 3516. By examining their correlation, we found that the X-ray flux preceded that in the B band by 2.0-0.6+0.07 days (1σ error). Although this result supports the X-ray reprocessing model, the derived lag is too large to be explained by the standard view, which assumes a "lamppost"-type X-ray illuminator located near a standard accretion disk. Our results are better explained by assuming a hot accretion flow and a truncated disk.

      DOI: 10.3847/0004-637X/828/2/78

      Scopus

      researchmap

    • First application of superconducting transition-edge sensor microcalorimeters to hadronic atom X-ray spectroscopy 査読有り

      S. Okada, D. A. Bennett, C. Curceanu, W. B. Doriese, J. W. Fowler, J. D. Gard, F. P. Gustafsson, T. Hashimoto, R. S. Hayano, S. Hirenzaki, J. P. Hays-Wehle, G. C. Hilton, N. Ikeno, M. Iliescu, S. Ishimoto, K. Itahashi, M. Iwasaki, T. Koike, K. Kuwabara, Y. Ma, J. Marton, H. Noda, G. C. O'Neil, H. Outa, C. D. Reintsema, M. Sato, D. R. Schmidt, H. Shi, K. Suzuki, T. Suzuki, D. S. Swetz, H. Tatsuno, J. Uhlig, J. N. Ullom, E. Widmann, S. Yamada, J. Yamagata-Sekihara, J. Zmeskal

      PROGRESS OF THEORETICAL AND EXPERIMENTAL PHYSICSvol.2016 ( 9 ) 091D01   2016年9月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS INC  

      High-resolution pionic atom X-ray spectroscopy was performed with an X-ray spectrometer based on a 240 pixel array of superconducting transition-edge sensor (TES) microcalorimeters at the pi M1 beam line of the Paul Scherrer Institute. X-rays emitted by pionic carbon via the 4f -> 3d transition and the parallel 4d -> 3p transition were observed with a full width at half maximum energy resolution of 6.8 eV at 6.4 keV. The measured X-ray energies are consistent with calculated electromagnetic values which considered the strong interaction effect assessed via the Seki-Masutani potential for the 3p energy level, and favor the electronic population of two filled 1s electrons in the K-shell. Absolute energy calibration with an uncertainty of 0.1 eV was demonstrated under a high-rate hadron beam condition of 1.45 MHz. This is the first application of a TES spectrometer to hadronic atom X-ray spectroscopy and is an important milestone towards next-generation high-resolution kaonic atom X-ray spectroscopy.

      DOI: 10.1093/ptep/ptw130

      researchmap

    • X-RAY AND OPTICAL CORRELATION OF TYPE I SEYFERT NGC 3516 STUDIED WITH SUZAKU AND JAPANESE GROUND-BASED TELESCOPES 査読有り

      Hirofumi Noda, Takeo Minezaki, Makoto Watanabe, Mitsuru Kokubo, Kenji Kawaguchi, Ryosuke Itoh, Kumiko Morihana, Yoshihiko Saito, Hikaru Nakao, Masataka Imai, Yuki Moritani, Katsutoshi Takaki, Miho Kawabata, Tatsuya Nakaoka, Makoto Uemura, Koji Kawabata, Michitoshi Yoshida, Akira Arai, Yuhei Takagi, Tomoki Morokuma, Mamoru Doi, Yoichi Itoh, Shin'ya Yamada, Kazuhiro Nakazawa, Yasushi Fukazawa, Kazuo Makishima

      ASTROPHYSICAL JOURNAL828 ( 2 ) 78   2016年9月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      From 2013 April to 2014 April, we performed X-ray and optical simultaneous monitoring of the type 1.5 Seyfert galaxy NGC. 3516. We employed Suzaku and five Japanese ground-based telescopes-the Pirka, Kiso Schmidt, Nayuta, MITSuME, and the Kanata telescopes. The Suzaku observations were conducted seven times with various intervals ranging from days or weeks to months, with an exposure of similar to 50 ks each. The optical B-band observations not only covered those of Suzaku almost simultaneously, but also followed the source as frequently as possible. As a result, NGC. 3516 was found in its faint phase with a 2-10 keV flux of 0.21-2.70. x 10(-1)1 erg s(-1) cm(-2). The 2-45 keV X-ray spectra were composed of a dominant variable hard power-law (PL) continuum with a photon index of similar to 1.7 and a nonrelativistic reflection component with a prominent Fe-Ka emission line. Producing the B-band light curve by differential image photometry, we found that the B-band flux changed by similar to 2.7 x 10(-1)1 erg s(-1) cm(-2), which is comparable to the X-ray variation, and we detected a significant flux correlation between the hard PL component in X-rays and the B-band radiation, for the first time in NGC. 3516. By examining their correlation, we found that the X-ray flux preceded that in the B band by 2.0(-0.6)(+0.7) days (1 sigma error). Although this result supports the X-ray reprocessing model, the derived lag is too large to be explained by the standard view, which assumes a "lamppost"-type X-ray illuminator located near a standard accretion disk. Our results are better explained by assuming a hot accretion flow and a truncated disk.

      DOI: 10.3847/0004-637X/828/2/78

      researchmap

    • Absolute Energy Calibration of X-ray TESs with 0.04 eV Uncertainty at 6.4 keV in a Hadron-Beam Environment 査読有り

      H. Tatsuno, W. B. Doriese, D. A. Bennett, C. Curceanu, J. W. Fowler, J. Gard, F. P. Gustafsson, T. Hashimoto, R. S. Hayano, J. P. Hays-Wehle, G. C. Hilton, M. Iliescu, S. Ishimoto, K. Itahashi, M. Iwasaki, K. Kuwabara, Y. Ma, J. Marton, H. Noda, G. C. O'Neil, S. Okada, H. Outa, C. D. Reintsema, M. Sato, D. R. Schmidt, H. Shi, K. Suzuki, T. Suzuki, J. Uhlig, J. N. Ullom, E. Widmann, S. Yamada, J. Zmeskal, D. S. Swetz

      JOURNAL OF LOW TEMPERATURE PHYSICS184 ( 3-4 ) 930 - 937   2016年8月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER/PLENUM PUBLISHERS  

      A performance evaluation of superconducting transition-edge sensors (TESs) in the environment of a pion beam line at a particle accelerator is presented. Averaged across the 209 functioning sensors in the array, the achieved energy resolution is 5.2 eV FWHM at Co (6.9 keV) when the pion beam is off and 7.3 eV at a beam rate of 1.45 MHz. Absolute energy uncertainty of 0.04 eV is demonstrated for Fe (6.4 keV) with in-situ energy calibration obtained from other nearby known X-ray lines. To achieve this small uncertainty, it is essential to consider the non-Gaussian energy response of the TESs and thermal cross-talk pile-up effects due to charged particle hits in the silicon substrate of the TES array.

      DOI: 10.1007/s10909-016-1491-2

      researchmap

    • Future Japanese X-ray TES Calorimeter Satellite: DIOS (Diffuse Intergalactic Oxygen Surveyor) 査読有り

      S. Yamada, T. Ohashi, Y. Ishisaki, Y. Ezoe, N. Miyazaki, K. Kuwabara, G. Kuromaru, S. Suzuki, K. Mitsuda, N. Y. Yamasaki, Y. Takei, K. Sakai, K. Nagayoshi, R. Yamamoto, T. Hayashi, H. Muramatsu, Y. Tawara, I. Mitsuishi, Y. Babazaki, R. Nakamichi, A. Bandai, T. Yuasa, N. Ota

      JOURNAL OF LOW TEMPERATURE PHYSICS184 ( 3-4 ) 688 - 693   2016年8月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER/PLENUM PUBLISHERS  

      We present the latest update and progress on the future Japanese X-ray satellite mission Diffuse Intergalactic Oxygen Surveyor (DIOS). DIOS is proposed to JAXA as a small satellite mission, and would be launched with an Epsilon rocket. DIOS would carry on the legacy of ASTRO-H, which carries semiconductor-based microcalorimeters and is scheduled to be launched in 2016, in high-resolution X-ray spectroscopy. A 400-pixel array of transition-edge sensors (TESs) would be employed, so DIOS would also provide valuable lessons for the next ESA X-ray mission ATHENA on TES operation and cryogen-free cooling in space. We have been sophisticating the entire design of the satellite to meet the requirement for the Epsilon payload for the next call. The primary goal of the mission is to search for warm-hot intergalactic medium with high-resolution X-ray spectroscopy by detecting redshifted emission lines from OVII and OVIII ions. The results would have significant impacts on our understanding of the nature of "dark baryons," their total amount and spatial distribution, as well as their evolution over cosmological timescales.

      DOI: 10.1007/s10909-015-1362-2

      researchmap

    • Investigation of Surface Roughness Effect on Transition Edge Sensor Microcalorimeters Using Multilayer Readout Wiring 査読有り

      G. Kuromaru, K. Kuwabara, N. Miyazaki, S. Suzuki, S. Hosoya, Y. Koizumi, T. Ohashi, Y. Ishisaki, Y. Ezoe, S. Yamada, K. Mitsuda, M. Hidaka, T. Satoh

      JOURNAL OF LOW TEMPERATURE PHYSICS184 ( 1-2 ) 38 - 44   2016年7月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER/PLENUM PUBLISHERS  

      We are developing a transition edge sensor (TES) using multilayer readout wiring for future X-ray astronomy satellites. Although we fabricated a first full 2020 pixels TES array, we could not confirm transition of the TES. Considering possible causes, we focused on surface roughness of the TES film. We checked the fabrication process steps that can influence the surface roughness step by step, and changed wiring material (Al to Nb) and also a process condition of an ion milling. As a result, we succeeded to reduce the surface roughness from 4.5 to 2.5 nm rms at 1 m scale. However, the transition was not observed probably because the TES films in our samples with surface roughness more than nm rms tend not to show the transition. Therefore, to suppress the surface roughness even more, we discuss possible process effects and mitigations.

      DOI: 10.1007/s10909-016-1499-7

      researchmap

    • Temporal Gain Correction for X-ray Calorimeter Spectrometers 査読有り

      F. S. Porter, M. P. Chiao, M. E. Eckart, R. Fujimoto, Y. Ishisaki, R. L. Kelley, C. A. Kilbourne, M. A. Leutenegger, D. McCammon, K. Mitsuda, M. Sawada, A. E. Szymkowiak, Y. Takei, M. Tashiro, M. Tsujimoto, T. Watanabe, S. Yamada

      JOURNAL OF LOW TEMPERATURE PHYSICS184 ( 1-2 ) 498 - 504   2016年7月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER/PLENUM PUBLISHERS  

      Calorimetric X-ray detectors are very sensitive to their environment. The boundary conditions can have a profound effect on the gain including heat sink temperature, the local radiation temperature, bias, and the temperature of the readout electronics. Any variation in the boundary conditions can cause temporal variations in the gain of the detector and compromise both the energy scale and the resolving power of the spectrometer. Most production X-ray calorimeter spectrometers, both on the ground and in space, have some means of tracking the gain as a function of time, often using a calibration spectral line. For small gain changes, a linear stretch correction is often sufficient. However, the detectors are intrinsically non-linear and often the event analysis, i.e., shaping, optimal filters etc., add additional non-linearity. Thus for large gain variations or when the best possible precision is required, a linear stretch correction is not sufficient. Here, we discuss a new correction technique based on non-linear interpolation of the energy-scale functions. Using Astro-H/SXS calibration data, we demonstrate that the correction can recover the X-ray energy to better than 1 part in 10 over the entire spectral band to above 12 keV even for large-scale gain variations. This method will be used to correct any temporal drift of the on-orbit per-pixel gain using on-board calibration sources for the SXS instrument on the Astro-H observatory.

      DOI: 10.1007/s10909-016-1503-2

      researchmap

    • The quiescent intracluster medium in the core of the Perseus cluster 査読有り

      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, Francois 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, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian McNamara, Missagh Mehdipour, Eric Miller, Jon Miller, Shin Mineshige, Kazuhisa Mitsuda, Ikuyuki Mitsuishi, Takuya Miyazawa, Tsunefumi Mizuno, Hideyuki Mori, Koji Mori, Harvey Moseley, Koji Mukai, Hiroshi Murakami, Toshio Murakami, Richard Mushotzky, Ryo Nagino, Takao Nakagawa, Hiroshi Nakajima, Takeshi Nakamori, Toshio Nakano, Shinya Nakashima, Kazuhiro Nakazawa, Masayoshi Nobukawa, Hirofumi Noda, Masaharu Nomachi, Steve O'Dell, Hirokazu Odaka, Takaya Ohashi, Masanori Ohno, Takashi Okajima, Naomi Ota, Masanobu Ozaki, Frits Paerels, Stephane Paltani, Arvind Parmar, Robert Petre, Ciro Pinto, Martin Pohl, F. Scott Porter, Katja Pottschmidt, Brian Ramsey, Christopher Reynolds, Helen Russell, Samar Safi-Harb, Shinya Saito, Kazuhiro Sakai, Hiroaki Sameshima, Goro Sato, Kosuke Sato, Rie Sato, Makoto Sawada, Norbert Schartel, Peter Serlemitsos, Hiromi Seta, Megumi Shidatsu, Aurora Simionescu, Randall Smith, Yang Soong, Lukasz Stawarz, Yasuharu Sugawara, Satoshi Sugita, Andrew Szymkowiak, Hiroyasu Tajima, Hiromitsu Takahashi, Tadayuki Takahashi, Shin'ichiro Takeda, Yoh Takei, Toru Tamagawa, Keisuke Tamura, Takayuki Tamura, Takaaki Tanaka, Yasuo Tanaka, Yasuyuki Tanaka, Makoto Tashiro, Yuzuru Tawara, Yukikatsu Terada, Yuichi Terashima, Francesco Tombesi, Hiroshi Tomida, Yohko Tsuboi, Masahiro Tsujimoto, Hiroshi Tsunemi, Takeshi Tsuru, Hiroyuki Uchida, Hideki Uchiyama, Yasunobu Uchiyama, Shutaro Ueda, Yoshihiro Ueda, Shiro Ueno, Shin'ichiro Uno, Meg Urry, Eugenio Ursino, Cor De Vries, Shin Watanabe, Norbert Werner, Daniel Wik, Dan Wilkins, Brian Williams, Shinya Yamada, Hiroya Yamaguchi, Kazutaka Yamaoka, Noriko Y. Yamasaki, Makoto Yamauchi, Shigeo Yamauchi, Tahir Yaqoob, Yoichi Yatsu, Daisuke Yonetoku, Atsumasa Yoshida, Takayuki Yuasa, Irina Zhuravleva, Abderahmen Zoghbi

      NATURE535 ( 7610 ) 117 - +   2016年7月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:NATURE PUBLISHING GROUP  

      Clusters of galaxies are the most massive gravitationally bound objects in the Universe and are still forming. They are thus important probes(1) 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(2-6). 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: 10.1038/nature18627

      researchmap

    • SUZAKU OBSERVATION OF THE HIGH-INCLINATION BINARY EXO 0748-676 IN THE HARD STATE 査読有り

      Zhongli Zhang, Soki Sakurai, Kazuo Makishima, Kazuhiro Nakazawa, Ko Ono, Shin'ya Yamada, Haiguang Xu

      ASTROPHYSICAL JOURNAL823 ( 2 ) 131   2016年6月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      Utilizing archived Suzaku data acquired on 2007 December 25 for 46 ks, the X-ray spectroscopic properties of the dipping and eclipsing low-mass X-ray binary EXO 0748-676 were studied. At an assumed distance of 7.1 kpc, the data provided a persistent unabsorbed luminosity of 3.4 x 10(36) erg cm(-2) s(-1) in 0.6-55 keV. The source was in a relatively bright low/hard state, wherein the 0.6-55 keV spectrum can be successfully explained by a "double-seed" Comptonization model incorporating a common corona with an electron temperature of similar to 13 keV. The seed photons are thought to be supplied from both the neutron star surface and a cooler truncated disk. Compared to a sample of non-dipping, low-mass X-ray binaries in the low/hard state, the spectrum is subject to stronger Comptonization with a relatively larger Comptonizing y-parameter of similar to 1.4 and a larger coronal optical depth of similar to 5. This result, when attributed to the high inclination of EXO 0748-676, suggests that the Comptonizing corona may elongate along the disk plane and provide a longer path for the seed photons when viewed from edge-on inclinations.

      DOI: 10.3847/0004-637X/823/2/131

      researchmap

    • The new primary X-ray component confirmed in the Seyfert I galaxy IC 4329A 査読有り

      Katsuma Miyake, Hirofumi Noda, Shin'ya Yamada, Kazuo Makishima, Kazuhiro Nakazawa

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN68   S28   2016年6月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      The bright and highly variable Seyfert I active galactic nucleus IC 4329A was observed with Suzaku five times in 2007 August, with intervals of similar to 5 days and a net exposure of 24-31 ks each. Another longer observation was carried out in 2012 August with a net exposure of 118 ks. In the six observations, a source was detected in 2-45 keV with an average 2-10 keV fluxes of (0.67-1.2) x 10(-10) erg cm(-2) s(-1). Its intensity changed by a factor of 2 among the five observations in 2007, and 1.5 within the 2012 observation. A difference of spectrum among these observations revealed that the variability of IC4329A was carried mainly by a power-law component with a photon index Gamma similar to 2.0. However, in addition to this primary component and its associated reflection, the broad-band Suzaku data required another, harder, and less-variable component with Gamma similar to 1.4. The presence of this new continuum was also confirmed by analyzing the same six data sets through the spectral decomposition technique developed by Noda et al. (2013a, ApJ, 771, 100). This Gamma similar to 1.4 continuum is considered to be a new primary component that has not been recognized in the spectra of IC 4329A so far, although it was recently identified in those of several other Seyfert I galaxies (Noda et al. 2013a, ApJ, 771, 100; Noda et al. 2014, ApJ, 794, 2).

      DOI: 10.1093/pasj/psw025

      researchmap

    • TRANSITING PLANET CANDIDATES BEYOND THE SNOW LINE DETECTED BY VISUAL INSPECTION OF 7557 KEPLER OBJECTS OF INTEREST 査読有り

      Sho Uehara, Hajime Kawahara, Kento Masuda, Shin'ya Yamada, Masataka Aizawa

      ASTROPHYSICAL JOURNAL822 ( 1 ) 2   2016年5月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      We visually inspected the light curves of 7557 Kepler Objects of Interest (KOIs) to search for single. transit events (STEs) that were possibly due to long-period giant planets. We identified 28 STEs in 24 KOIs, among which 14 events are newly reported in this paper. We estimate the radius and orbital period of the objects causing STEs by fitting the STE light curves simultaneously with the transits of the other planets in the system or with. prior information on the host star density. As a result, we found that STEs in seven of those systems are consistent with Neptune- to Jupiter-sized objects of orbital periods ranging from a few to similar to 20 years. We also estimate that. greater than or similar to 20% of the compact multi-transiting systems host cool giant planets with periods greater than or similar to 3 years on the basis of their occurrence in the KOIs with multiple candidates, assuming the small mutual inclination between inner and outer planetary orbits.

      DOI: 10.3847/0004-637X/822/1/2

      researchmap

    • On-ground detection of an electron-positron annihilation line from thunderclouds 査読有り

      D. Umemoto, H. Tsuchiya, T. Enoto, S. Yamada, T. Yuasa, M. Kawaharada, T. Kitaguchi, K. Nakazawa, M. Kokubun, H. Kato, M. Okano, T. Tamagawa, K. Makishima

      Physical Review E93 ( 2 )   2016年2月16日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:American Physical Society  

      Thunderclouds can produce bremsstrahlung gamma-ray emission, and sometimes even positrons. At 00:27:00 (UT) on 13 January 2012, an intense burst of gamma rays from a thundercloud was detected by the GROWTH experiment, located in Japan, facing the Sea of Japan. The event started with a sharp gamma-ray flash with a duration of &lt
      300 ms coincident with an intracloud discharge, followed by a decaying longer gamma-ray emission lasting for ∼60 s. The spectrum of this prolonged emission reached ∼10 MeV, and contained a distinct line emission at 508±3(stat.)±5(sys.) keV, to be identified with an electron-positron annihilation line. The line was narrow within the instrumental energy resolution (∼80keV), and contained 520±50 photons which amounted to ∼10% of the total signal photons of 5340±190 detected over 0.1-10 MeV. As a result, the line equivalent width reached 280±40 keV, which implies a nontrivial result. The result suggests that a downward positron beam produced both the continuum and the line photons.

      DOI: 10.1103/PhysRevE.93.021201

      Scopus

      researchmap

      その他リンク: http://orcid.org/0000-0003-3529-3029

    • Calibration of the microcalorimeter spectrometer on-board the Hitomi (Astro-H) observatory 査読有り

      Eckart, M. E., Boyce, K. R., Brown, G. V., Chiao, M. P., Fujimoto, R., Haas, D., den Herder, J. -W., Ishisaki, Y., Kelley, R. L., Kilbourne, C. A., Leutenegger, M. A., McCammon, D., Mitsuda, K., Porter, F. S., Sawada, M., Sneiderman, G. A., Szymkowiak, A. E., Takei, Y., Tashiro, M., Tsujimoto, M., de Vries, C. P., Watanabe, T., Yamada, S., Yamasaki, N. Y.

      Review of Scientific Instruments87 ( 11 )   2016年

      詳細を見る

      掲載種別:研究論文(学術雑誌)  

      DOI: 10.1063/1.4961075

      researchmap

    • In-flight verification of the calibration and performance of the ASTRO-H (Hitomi) Soft X-ray Spectrometer 査読有り

      Maurice A. Leutenegger, Marc Audard, Kevin R. Boyce, Gregory V. Brown, Meng P. Chiao, Megan E. Eckart, Ryuichi Fujimoto, Akihiro Furuzawa, Matteo Guainazzi, Daniel Haas, Jan-Willem den Herder, Takayuki Hayashi, Ryo Iizuka, Manabu Ishida, Yoshitaka Ishisaki, Richard L. Kelley, Naomichi Kikuchig, Caroline A. Kilbourne, Shu Koyama, Sho Kurashima, Yoshitomo Maeda, Maxim Markevitch, Dan McCammon, Kazuhisa Mitsuda, Hideyuki Mori, Nozomi Nakaniwa, Takashi Okajima, Stephane Paltani, Robert Petre, F. Scott Porter, Kosuke Sato, Toshiki Sato, Makoto Sawada, Peter J. Serlemitsos, Hiromi Seta, Gary Sneiderman, Yang Soong, Satoshi Sugita, Andrew E. Szymkowiak, Yoh Takei, Makoto Tashiro, Yuzuru Tawara, Masahiro Tsujimoto, Cor P. de Vries, Tomomi Watanabe, Shinya Yamada, Noriko Yamasaki

      SPACE TELESCOPES AND INSTRUMENTATION 2016: ULTRAVIOLET TO GAMMA RAY9905   021407   2016年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:SPIE-INT SOC OPTICAL ENGINEERING  

      The Soft X-ray Spectrometer (SXS) onboard the Astro-H (Hitomi) orbiting x-ray observatory featured an array of 36 silicon thermistor x-ray calorimeters optimized to perform high spectral resolution x-ray imaging spectroscopy of astrophysical sources in the 0.3-12 keV band. Extensive pre-flight calibration measurements are the basis for our modeling of the pulse-height-energy relation and energy resolution for each pixel and event grade, telescope collecting area, detector efficiency, and pulse arrival time.
      Because of the early termination of mission operations, we needed to extract the maximum information from observations performed only days into the mission when the onboard calibration sources had not yet been commissioned and the dewar was still coming into thermal equilibrium, so our technique for reconstructing the per-pixel time-dependent pulse-height-energy relation had to be modified. The gain scale was reconstructed using a combination of an absolute energy scale calibration at a single time using a fiducial from an onboard radioactive source, and calibration of a dominant time-dependent gain drift component using a dedicated calibration pixel, as well as a residual time-dependent variation using spectra from the Perseus cluster of galaxies.
      The energy resolution was also measured using the onboard radioactive sources. It is consistent with instrument-level measurements accounting for the modest increase in noise due to spacecraft systems interference. We use observations of two pulsars to validate our models of the telescope area and detector efficiency, and to derive a more accurate value for the thickness of the gate valve Be window, which had not been opened by the time mission operations ceased. We use observations of the Crab pulsar to refine the pixel-to-pixel timing and validate the absolute timing.

      DOI: 10.1117/12.2234230

      researchmap

    • In-orbit operation of the ASTRO-H SXS 査読有り

      Masahiro Tsujimoto, Kazuhisa Mitsuda, Richard L. Kelley, Jan-Willem A. Den Herder, Hiroki Akamatsu, Thomas G. Bialas, Kevin R. Boyce, Gregory V. Brown, Meng P. Chiao, Elisa Costantini, Cor P. De Vries, Michael J. DiPirro, Megan E. Eckart, Yuichiro Ezoe, Ryuichi Fujimoto, Daniel Haas, Akio Hoshino, Kumi Ishikawa, Yoshitaka Ishisaki, Naoko Iyomoto, Caroline A. Kilbourne, Shunji Kitamoto, Shu Koyama, Maurice A. Leutenegger, Dan McCammon, Ikuyuki Mitsuishi, Hiroshi Murakami, Masahide Murakami, Hirofumi Noda, Mina Ogawa, Naomi Ota, Stéphane Paltani, Frederick S. Porter, Kosuke Sato, Yoichi Sato, Makoto Sawada, Hiromi Seta, Keisuke Shinozaki, Peter J. Shirron, Gary A. Sneiderman, Hiroyuki Sugita, Andrew E. Szymkowiak, Yoh Takei, Toru Tamagawa, Makoto S. Tashiro, Yukikatsu Terada, Shinya Yamada, Noriko Y. Yamasaki, Yoichi Yatsu

      Proceedings of SPIE - The International Society for Optical Engineering9905   2016年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:SPIE  

      We summarize all the in-orbit operations of the Soft X-ray Spectrometer (SXS) onboard the ASTRO-H (Hitomi) satellite. The satellite was launched on 2016/02/17 and the communication with the satellite ceased on 2016/03/26. The SXS was still in the commissioning phase, in which the setups were progressively changed. This article is intended to serve as a reference of the events in the orbit to properly interpret the SXS data taken during its short life time, and as a test case for planning the in-orbit operation for future micro-calorimeter missions.

      DOI: 10.1117/12.2231784

      Scopus

      researchmap

    • Performance of the helium dewar and cryocoolers of ASTRO-H SXS

      Ryuichi Fujimoto, Yoh Takei, Kazuhisa Mitsuda, Noriko Y. Yamasaki, Masahiro Tsujimoto, Shu Koyama, Kumi Ishikawa, Hiroyuki Sugita, Yoichi Sato, Keisuke Shinozaki, Atsushi Okamoto, Shunji Kitamoto, Akio Hoshino, Kosuke Sato, Yuichiro Ezoe, Yoshitaka Ishisaki, Shinya Yamada, Hiromi Seta, Takaya Ohashi, Toru Tamagawa, Hirofumi Noda, Makoto Sawada, Makoto Tashiro, Yoichi Yatsu, Ikuyuki Mitsuishi, Kenichi Kanao, Seiji Yoshida, Mikio Miyaoka, Shoji Tsunematsu, Kiyomi Otsuka, Katsuhiro Narasaki, Michael J. DiPirro, Peter J. Shirron, Gary A. Sneiderman, Caroline A. Kilbourne, F. Scott Porter, Meng P. Chiao, Megan E. Eckart, Richard L. Kelley

      SPACE TELESCOPES AND INSTRUMENTATION 2016: ULTRAVIOLET TO GAMMA RAY9905   99053S   2016年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:SPIE-INT SOC OPTICAL ENGINEERING  

      The Soft X-ray Spectrometer (SXS) is a cryogenic high-resolution X-ray spectrometer onboard the ASTRO-H satellite, that achieves energy resolution better than 7 eV at 6 keV, by operating the detector array at 50 mK using an adiabatic demagnetization refrigerator. The cooling chain from room temperature to the ADR heat sink is composed of 2-stage Stirling cryocoolers, a He-4 Joule-Thomson cryocooler, and superfluid liquid He, and is installed in a dewar. It is designed to achieve a helium lifetime of more than 3 years with a minimum of 30 liters. The satellite was launched on 2016 February 17, and the SXS worked perfectly in orbit, until March 26 when the satellite lost its function. It was demonstrated that the heat load on the He tank was about 0.7 mW, which would have satisfied the lifetime requirement. This paper describes the design, results of ground performance tests, prelaunch operations, and initial operation and performance in orbit of the flight dewar and cryocoolers.

      DOI: 10.1117/12.2232933

      researchmap

    • The ASTRO-H (Hitomi) X-ray astronomy satellite 査読有り

      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 Engineering9905   2016年

      詳細を見る

      掲載種別:研究論文(国際会議プロシーディングス)  

      © 2016 SPIE. 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: 10.1117/12.2232379

      Scopus

      researchmap

    • The Astro-H high resolution soft X-ray spectrometer 査読有り

      Richard L. Kelley, Hiroki Akamatsu, Phillipp Azzarell, Tom Bialas, Kevin R. Boyce, Gregory V. Brown, Edgar Canavan, Meng P. Chiao, Elisa Costantini, Michael J. DiPirro, Megan E. Eckart, Yuichiro Ezoe, Ryuichi Fujimoto, Daniel Haas, Jan-Willem Den Herder, Akio Hoshino, Kumi Ishikawa, Yoshitaka Ishisaki, Naoko Iyomoto, Caroline A. Kilbourne, Mark Kimball, Shunji Kitamoto, Saori Konami, Shu Koyama, Maurice A. Leutenegger, Dan McCammon, Joseph Miko, Kazuhisa Mitsuda, Ikuyuki Mitsuishi, Harvey Moseley, Hiroshi Murakami, Masahide Murakami, Hirofumi Noda, Mina Ogawa, Takaya Ohashi, Atsushi Okamoto, Naomi Ota, Stéphane Paltani, F. Scott Porter, Kazuhiro Sakai, Kosuke Sato, Yohichi Sato, Makoto Sawada, Hiromi Seta, Keisuke Shinozaki, Peter J. Shirron, Gary A. Sneiderman, Hiroyuki Sugita, Andrew E. Szymkowiak, Yoh Takei, Toru Tamagawa, Makoto Tashiro, Yukikatsu Terada, Masahiro Tsujimoto, Cor P. De Vries, Shinya Yamada, Noriko Y. Yamasaki, Yoichi Yatsu

      Proceedings of SPIE - The International Society for Optical Engineering9905   2016年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:SPIE  

      We present the overall design and performance of the Astro-H (Hitomi) Soft X-Ray Spectrometer (SXS). The instrument uses a 36-pixel array of x-ray microcalorimeters at the focus of a grazing-incidence x-ray mirror Soft X-Ray Telescope (SXT) for high-resolution spectroscopy of celestial x-ray sources. The instrument was designed to achieve an energy resolution better than 7 eV over the 0.3-12 keV energy range and operate for more than 3 years in orbit. The actual energy resolution of the instrument is 4-5 eV as demonstrated during extensive ground testing prior to launch and in orbit. The measured mass flow rate of the liquid helium cryogen and initial fill level at launch predict a lifetime of more than 4 years assuming steady mechanical cooler performance. Cryogen-free operation was successfully demonstrated prior to launch. The successful operation of the SXS in orbit, including the first observations of the velocity structure of the Perseus cluster of galaxies, demonstrates the viability and power of this technology as a tool for astrophysics.

      DOI: 10.1117/12.2232509

      Scopus

      researchmap

    • Vibration isolation system for cryocoolers of Soft X-ray Spectrometer (SXS) onboard ASTRO-H (Hitomi) 査読有り

      Yoh Takei, Susumu Yasuda, Kosei Ishimura, Naoko Iwata, Atsushi Okamoto, Yoichi Sato, Mina Ogawa, Makoto Sawada, Taro Kawano, Shingo Obara, Chikara Natsukari, Atsushi Wada, Shinya Yamada, Ryuichi Fujimoto, Motohide Kokubun, Noriko Y. Yamasaki, Hiroyuki Sugita, Kenji Minesugi, Yasuo Nakamura, Kazuhisa Mitsuda, Tadayuki Takahashi, Seiji Yoshida, Shoji Tsunematsu, Kenichi Kanao, Katsuhiro Narasaki, Kiyomi Otsuka, Richard L. Kelley, F. Scott Porter, Caroline A. Kilbourne, Meng P. Chiao, Megan E. Eckart, Gary A. Sneiderman, James T. Pontius, Dan McCammon, Paul Wilke, John Basile

      SPACE TELESCOPES AND INSTRUMENTATION 2016: ULTRAVIOLET TO GAMMA RAY9905   2016年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:SPIE-INT SOC OPTICAL ENGINEERING  

      Soft X-ray Spectrometer (SXS) onboard ASTRO-H (named Hitomi after launch) is a microcalorimeter-type spectrometer, installed in a dewar to be cooled at 50 mK. The energy resolution of the SXS engineering model suffered from micro-vibration from cryocoolers mounted on the dewar. This is mitigated for the flight model by introducing vibration isolation systems between the cryocoolers and the dewar. The detector performance of the flight model was verified before launch of the spacecraft in both ambient condition and thermal-vac condition, showing no detectable degradation in energy resolution. The in-orbit performance was also consistent with that on ground, indicating that the cryocoolers were not damaged by launch environment. The design and performance of the vibration isolation system along with the mechanism of how the micro-vibration could degrade the cryogenic detector is shown.

      DOI: 10.1117/12.2231832

      researchmap

    • Tapered edge readout wiring for transition edge sensor calorimeter arrays using ion milling

      Yuichiro Ezoe, Noriko Iijima, Seiya Yamaguchi, Naoto Miyazaki, Shinya Yamada, Yoshitaka Ishisaki, Takaya Ohashi, Kazuhisa Mitsuda, Tetsuro Satoh, Mutsuo Hidaka

      IEEE Transactions on Applied Superconductivity25 ( 3 )   2015年6月1日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Institute of Electrical and Electronics Engineers Inc.  

      We are developing transition edge sensor (TES) arrays using multilayer superconducting readout wiring for future X-ray astronomical missions. The TES pixels are formed on the multilayer readout wiring composed of hot and return wires sandwiching an insulation layer. The interface between the wiring and the TES is formed by patterning the topmost wiring layer followed by deposition of the TES layer. To mitigate problems found in a past device, edges of the upper readout wiring are tapered with an ion milling method to enhance an electrical contact between the TES film and the upper readout wiring. To verify this design, we fabricated a 400-pixel test array with the TES pixels on the tapered upper readout wiring. Good physical contact between the TES film and the readout wiring was confirmed with scanning electron microscope. Furthermore, a low transition temperature (~160 mK), a sharp transition edge and a low residual resistance (~1 mΩ) were observed in RT measurements of representative pixels. The critical current was small 10 ~ 30 μA, although it is still larger than the previous device (&lt
      10 μA). These results suggest that this method will enable a multilayer wiring TES array with good electrical properties.

      DOI: 10.1109/TASC.2014.2374415

      Scopus

      researchmap

    • Suzaku observation of X-ray variability in soft state LMCX-1 査読有り

      Shu Koyama, Shin'ya Yamada, Aya Kubota, Makoto S. Tashiro, Yukikatsu Terada, Kazuo Makishima

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN67 ( 3 ) 46   2015年6月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      This paper reports the results of Suzaku observation of the spectral variation of the black hole binary LMCX-1 in the soft state. The observation was carried out in 2009 from July 21 to 24. the obtained net count rate was similar to 30 counts s(-1) in the 0.5-50 keV band with similar to 10% peak-to-peak flux variation. The time-averaged X-ray spectrum cannot be described by a multi-color disk and single Compton component with its reflection, but requires additional Comptonized emissions. This double Compton component model allows a slightly larger inner radius of the multi-color disk, implying a lower spin parameter. Significant spectral evolution was observed above 8 keV along with a flux decrease on a timescale of similar to 10(4)-10(5) s. By spectral fitting, we show that this behavior is well explained by changes in the hard Comptonized emission component in contrast to the maintained disk and soft Comptonized emission.

      DOI: 10.1093/pasj/psv017

      researchmap

    • A Compton-thick AGN in the barred spiral galaxy NGC 4785 査読有り

      P. Gandhi, S. Yamada, C. Ricci, D. Asmus, R. F. Mushotzky, Y. Ueda, Y. Terashima, V. La Parola

      MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY449 ( 2 ) 1845 - 1855   2015年5月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      We present X-ray observations of the active galactic nucleus (AGN) in NGC 4785. The source is a local Seyfert 2 which has not been studied so far in much detail. It was recently detected with high significance in the 15-60 keV band in the 66-month Swift/BAT (Burst Array Telescope) all sky survey, but there have been no prior pointed X-ray observations of this object. With Suzaku, we clearly detect the source below 10 keV, and find it to have a flat continuum and prominent neutral iron fluorescence line with equivalent width greater than or similar to 1 keV. Fitting the broad-band spectra with physical reflection models shows the source to be a Compton-thick AGN with N-H of at least 2 x 10(24) cm(-2) and absorption-corrected 2-10 keV X-ray power L2-10 similar to few times 10(42) erg s(-1). Realistic uncertainties on L2-10 computed from the joint confidence interval on the intrinsic power-law continuum photon index and normalization are at least a factor of 10. The local bona fide Compton-thick AGN population is highly heterogeneous in terms of WISE mid-infrared source colours, and the nucleus of NGC 4785 appears especially sub-dominant in the mid-infrared when comparing to other Compton-thick AGN. Such sources would not be easily found using mid-infrared selection alone. The extent of host galaxy extinction to the nucleus is not clear, though NGC 4785 shows a complex core with a double bar and inner disc, adding to the list of known Compton-thick AGN in barred host galaxies.

      DOI: 10.1093/mnras/stv344

      researchmap

    • Repeated short-term spectral softening in the low/hard state of the Galactic black hole candidate Swift J1753.5-0127 査読有り

      Akifumi Yoshikawa, Shin'Ya Yamada, Satoshi Nakahira, Masaru Matsuoka, Hitoshi Negoro, Tatehiro Mihara, Toru Tamagawa

      Publications of the Astronomical Society of Japan67 ( 1 ) 11   2015年

      詳細を見る

      掲載種別:研究論文(学術雑誌)  

      © The Author 2014. We report MAXI and Swift observations of short-term spectral softenings of the Galactic black hole X-ray binary Swift J1753.5-0127 in the low/hard state. These softening events are characterized by a simultaneous increase of soft X-rays (2-4 keV) and a decrease of hard X-rays (15-50 keV) lasting for a few tens of days. The X-ray energy spectra during the softening periods can be reproduced with a model consisting of a multi-color disk blackbody and its Comptonized component. The fraction of the Comptonized component decreased from 0.30 to 0.15 when the spectrum became softer; meanwhile the inner disk temperature (Tin) increased from 0.2 to 0.45 keV. These results imply that the softening events are triggered by a short-term increase of the mass accretion rate. During the observed spectral softening events, the disk flux (Fdisk) and Tin did not obey the Fdisk ∝ (Tin )4 relation, suggesting that the inner disk radius does not reach the innermost stable circular orbit.

      DOI: 10.1093/pasj/psu140

      Scopus

      researchmap

    • SUZAKU STUDIES OF THE CENTRAL ENGINE IN THE TYPICAL TYPE I SEYFERT NGC 3227: DETECTION OF MULTIPLE PRIMARY X-RAY CONTINUA WITH DISTINCT PROPERTIES 査読有り

      Hirofumi Noda, Kazuo Makishima, Shin'ya Yamada, Kazuhiro Nakazawa, Soki Sakurai, Katsuma Miyake

      ASTROPHYSICAL JOURNAL794 ( 1 ) 2   2014年10月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      The type I Seyfert galaxy NGC 3227 was observed by Suzaku six times in 2008, with intervals of similar to 1 week and net exposures of similar to 50 ks each. Among the six observations, the source varied by nearly an order of magnitude; it was brightest in the first observation with a 2-10 keV luminosity of 1.2 x 10(42) erg s(-1), while faintest in the fourth observation with 2.9 x 10(41) erg s(-1). As it became fainter, the continuum in the 2-45 keV band became harder, while the narrow Fe-Ka emission line, detected on all occasions at 6.4 keV of the source rest frame, remained approximately constant in the photon flux. Through a method of variability-assisted broadband spectroscopy, the 2-45 keV spectrum of NGC 3227 was decomposed into three distinct components. One is a relatively soft powerlaw continuum with a photon index of similar to 2.3, weakly absorbed and highly variable on timescales of similar to 5 ks; it was observed only when the source was above a threshold luminosity of similar to 6.6 x 10(41) erg s(-1) (in 2-10 keV), and was responsible for further source brightening beyond. Another is a harder and more absorbed continuum with a photon index of similar to 1.6, which persisted through the six observations and varied slowly on timescales of a few weeks by a factor of similar to 2. This component, carrying a major fraction of the broadband emission when the source is below the threshold luminosity, is considered as an additional primary emission. The last one is a reflection component with the narrow iron line, produced at large distances from the central black hole.

      DOI: 10.1088/0004-637X/794/1/2

      researchmap

    • High-Resolution Kaonic-Atom X-ray Spectroscopy with Transition-Edge-Sensor Microcalorimeters 査読有り

      S. Okada, D. A. Bennett, W. B. Doriese, J. W. Fowler, K. D. Irwin, S. Ishimoto, M. Sato, D. R. Schmidt, D. S. Swetz, H. Tatsuno, J. N. Ullom, S. Yamada

      JOURNAL OF LOW TEMPERATURE PHYSICS176 ( 5-6 ) 1015 - 1021   2014年9月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER/PLENUM PUBLISHERS  

      We are preparing for an ultra-high resolution X-ray spectroscopy of kaonic atoms using an X-ray spectrometer based on an array of superconducting transition-edge-sensor microcalorimeters developed by NIST. The instrument has excellent energy resolutions of 2-3 eV (FWHM) at 6 keV and a large collecting area of about 20 mm. This will open new door to investigate kaon-nucleus strong interaction and provide new accurate charged-kaon mass value.

      DOI: 10.1007/s10909-014-1137-1

      researchmap

    • Development of Multilayer Readout Wiring TES Calorimeter for Future X-ray Missions 査読有り

      S. Yamada, Y. Ezoe, Y. Ishisaki, T. Ohashi, N. Iijima, K. Mitsuda, K. Nagayoshi, H. Akamatsu, T. Morooka, K. Tanaka

      JOURNAL OF LOW TEMPERATURE PHYSICS176 ( 3-4 ) 310 - 315   2014年8月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER/PLENUM PUBLISHERS  

      We have fabricated multilayer readout wiring transition edge sensors (TES), which enable us to realize both large effective area and high-energy resolution for future X-ray astrophysical missions, such as diffuse intergalactic oxygen surveyor. By sandwiching a SiO insulation layer between Al superconducting signal and return lines, self/mutual inductances and self fielding of bias leads are expected to be reduced. We fabricated and TES array on the multilayer wiring and tested their performance. Under the low temperature condition, several pixels in the TES array showed sharp superconducting transitions at around 300 mK. We also succeeded in detecting X-ray signals from the TES, contrary to the previous results of TES. We further investigated the reasons for the differences between the TES and the TES, and present future plans for improving the multilayer TES array fabrication.

      DOI: 10.1007/s10909-013-1056-6

      researchmap

    • Radiation Tolerance Evaluation of the Ti/Au Bilayer TES Microcalorimeter 査読有り

      Y. Ishisaki, Y. Enokijima, Y. Ezoe, T. Ohashi, H. Akamatsu, R. Yamamoto, Y. Takei, K. Mitsuda, N. Y. Yamasaki, S. Yamada

      JOURNAL OF LOW TEMPERATURE PHYSICS176 ( 3-4 ) 344 - 349   2014年8月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:SPRINGER/PLENUM PUBLISHERS  

      We have developed Ti/Au bilayer transition-edge sensor (TES) microcalorimeters for future X-ray astrophysical satellite missions such as DIOS. One possible concern on the space use of TES microcalorimeters is its radiation tolerance. We have evaluated the performance of a Ti/Au bilayer (30/40 nm thick) TES microcalorimeter with 1.5 m thick Au absorber, before and after irradiation of 150 MeV proton beam with a total dose of 10 krad, corresponding to 10 years in the low Earth orbit. No significant changes on transition temperature, sensitivity, normal resistance, and critical current were observed. The energy resolution for 5.9 keV X-rays was 5.6 0.3 eV (FWHM) after the irradiation, which was slightly worse than 5.1 0.3 eV before the irradiation. We consider that our TES has sufficient radiation tolerance in orbit.

      DOI: 10.1007/s10909-013-1058-4

      researchmap

    • SPECTRAL AND TIMING PROPERTIES OF THE BLACK HOLE X-RAY BINARY H1743-322 IN THE LOW/HARD STATE STUDIED WITH SUZAKU 査読有り

      M. Shidatsu, Y. Ueda, S. Yamada, C. Done, T. Hori, K. Yamaoka, A. Kubota, T. Nagayama, Y. Moritani

      ASTROPHYSICAL JOURNAL789 ( 2 ) 100   2014年7月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      We report on the results from Suzaku observations of the Galactic black hole X-ray binary H1743-322 in the low/hard state during its outburst in 2012 October. We appropriately take into account the effects of dust scattering to accurately analyze the X-ray spectra. The time-averaged spectra in the 1-200 keV band are dominated by a hard power-law component of a photon index of approximate to 1.6 with a high-energy cutoff at approximate to 60 keV, which is well described with the Comptonization of the disk emission by the hot corona. We estimate the inner disk radius from the multi-color disk component, and find that it is 1.3-2.3 times larger than the radius in the high/soft state. This suggests that the standard disk was not extended to the innermost stable circular orbit. A reflection component from the disk is detected with R = Omega/2 pi approximate to 0.6 (Omega is the solid angle). We also successfully estimate the stable disk component independent of the time-averaged spectral modeling by analyzing short-term spectral variability on a similar to 1 s timescale. A weak low-frequency quasi-periodic oscillation at 0.1-0.2 Hz is detected, whose frequency is found to correlate with the X-ray luminosity and photon index. This result may be explained by the evolution of the disk truncation radius.

      DOI: 10.1088/0004-637X/789/2/100

      researchmap

    • SPECTRAL AND TIMING NATURE OF THE SYMBIOTIC X-RAY BINARY 4U 1954+319: THE SLOWEST ROTATING NEUTRON STAR IN AN X-RAY BINARY SYSTEM 査読有り

      Teruaki Enoto, Makoto Sasano, Shin'ya Yamada, Toru Tamagawa, Kazuo Makishima, Katja Pottschmidt, Diana Marcu, Robin H. D. Corbet, Felix Fuerst, Joern Wilms

      ASTROPHYSICAL JOURNAL786 ( 2 ) 127   2014年5月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      The symbiotic X-ray binary (SyXB) 4U 1954+ 319 is a rare system hosting a peculiar neutron star (NS) and an M-type optical companion. Its similar to 5.4 hr NS spin period is the longest among all known accretion-powered pulsars and exhibited large (similar to 7%) fluctuations over 8 yr. A spin trend transition was detected with Swift/BAT around an X-ray brightening in 2012. The source was in quiescent and bright states before and after this outburst based on 60 ks Suzaku observations in 2011 and 2012. The observed continuum is well described by a Comptonized model with the addition of a narrow 6.4 keV Fe-K alpha line during the outburst. Spectral similarities to slowly rotating pulsars in high-mass X-ray binaries, its high pulsed fraction (similar to 60%-80%), and the location in the Corbet diagram favor high B-field (greater than or similar to 10(12) G) over a weak field as in low-mass X-ray binaries. The observed low X-ray luminosity (10(33)-10(35) erg s(-1)), probable wide orbit, and a slow stellar wind of this SyXB make quasi-spherical accretion in the subsonic settling regime a plausible model. Assuming a similar to 10(13) G NS, this scheme can explain the similar to 5.4 hr equilibrium rotation without employing the magnetar-like field (similar to 10(16) G) required in the disk accretion case. The timescales of multiple irregular flares (similar to 50 s) can also be attributed to the free-fall time from the Alfven shell for a similar to 10(13) G field. A physical interpretation of SyXBs beyond the canonical binary classifications is discussed.

      DOI: 10.1088/0004-637X/786/2/127

      researchmap

    • Broad-band spectroscopy of Hercules X-1 with Suzaku 査読有り

      Fumi Asami, Teruaki Enoto, Wataru Iwakiri, Shin'ya Yamada, Toru Tamagawa, Tatehiro Mihara, Fumiaki Nagase

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN66 ( 2 ) 44   2014年4月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      Hercules X-1 was observed with Suzaku in the main-on state from 2005 to 2010. The 0.4-100 keV wide-band spectra obtained in four observations showed a broad hump around 4-9 keV in addition to narrow Fe lines at 6.4 and 6.7 keV. The hump was seen in all the four observations regardless of the selection of the continuum models. Thus it is considered a stable and intrinsic spectral feature in Her X-1. The broad hump lacked a sharp structure like an absorption edge. Thus it was represented by two different spectral models: an ionized partial covering or an additional broad line at 6.5 keV. The former required a persistently existing ionized absorber, whose origin was unclear. In the latter case, the Gaussian fitting of the 6.5-keV line needs a large width of sigma = 1.0-1.5 keV and a large equivalent width of 400-900 eV. If the broad line originates from Fe fluorescence of accreting matter, its large width may be explained by the Doppler broadening in the accretion flow. However, the large equivalent width may be inconsistent with a simple accretion geometry.

      DOI: 10.1093/pasj/psu005

      researchmap

    • Suzaku studies of luminosity-dependent changes in the low-mass X-ray binary Aquila X-1 査読有り

      Soki Sakurai, Shunsuke Torii, Hirofumi Noda, Zhongli Zhang, Ko Ono, Kazuhiro Nakazawa, Kazuo Makishima, Hiromitsu Takahashi, Shin'ya Yamada, Masaru Matsuoka

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN66 ( 1 ) 10   2014年2月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      The neutron-star low-mass X-ray binary Aquila X-1 was observed by Suzaku seven times, from 2007 September 28 to October 30. The observations successfully traced an outburst decay in which the source luminosity decreased almost monotonically from similar to 10(37) erg s(-1) to similar to 10(34) erg s(-1), by similar to 3 orders of magnitude. To investigate luminosity-dependent changes in the accretion geometry, five of the seven data sets with a typical exposure of similar to 18 ks each were analyzed; the other two were utilized in a previous work (Sakurai et al. 2012, PASJ, 64, 72). The source was detected up to 100 keV in the second to the fourth observations, to 40 keV in the fifth, and to 10 keV on the last two occasions. All spectra were reproduced successfully by a Comptonized blackbody model with relatively high (greater than or similar to 2.0) optical depths, plus an additional softer optically-thick component. The faintest three spectra were reproduced alternatively by a single Comptonized blackbody model with a relatively low (less than or similar to 0.8) optical depth. The estimated radius of the blackbody emission, including seed photons for the Comptonization, was 10 +/- 2 km at a 0.8-100 keV luminosity of 2.4 x 10(36) erg s(-1) (the second to the fourth observations). In contrast, it decreased to 7 +/- 1 km and further to 3 +/- 1 km, at a luminosity of (4.8-5.2) x 10(35) erg s(-1) (the fifth observation) and similar to 2 x 10(34) erg s(-1) (the sixth and seventh), respectively, regardless of the above model ambiguity. This can be taken as evidence for the emergence of a weak magnetosphere from the neutron star.

      DOI: 10.1093/pasj/pst010

      researchmap

    • Property of LCP-GEM in pure dimethyl ether at low pressure 査読有り

      Y. Takeuchi, T. Tamagawa, T. Kitaguchi, S. Yamada, W. Iwakiri, F. Asami, A. Yoshikawa, K. Kaneko, T. Enoto, A. Hayato, T. Kohmura

      Journal of Instrumentation9 ( 1 )   2014年1月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)  

      We present a systematic investigation of the gain properties of a gas electron multiplier (GEM) foil in pure dimethyl ether (DME) at low pressures. The GEM is made from copper-clad liquid crystal polymer insulator (LCP-GEM) designed for space use, and is applied to a time projection chamber filled with low-pressure DME gas to observe the linear polarization of cosmic X-rays. We have measured gains of a 100 μm-thick LCP-GEM as a function of the voltage between GEM electrodes at various gas pressures ranging from 10 to 190 Torr with 6.4 keV X-rays. The highest gain at 190 Torr is about 2 × 104, while that at 20 Torr is about 500. We find that the pressure and electric-field dependence of the GEM gain is described by the first Townsend coefficient. The energy scale from 4.5 to 8.0 keV is linear with non-linearity of less than 1.4% above 30 Torr. © 2014 IOP Publishing Ltd and Sissa Medialab srl.

      DOI: 10.1088/1748-0221/9/01/C01002

      Scopus

      researchmap

    • DIOS: The dark baryon exploring mission

      T. Ohashi, Y. Ishisaki, Y. Ezoe, S. Yamada, S. Yamaguchi, N. Miyazaki, Y. Tawara, K. Mitsuda, N. Y. Yamasaki, Y. Takei, K. Sakai, K. Nagayoshi, R. Yamamoto, A. Chiba, T. Hayashi

      Proceedings of SPIE - The International Society for Optical Engineering9144   2014年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:SPIE  

      DIOS (Diffuse Intergalactic Oxygen Surveyor) is a small satellite aiming for a launch around 2020 with JAXA™s Epsilon rocket. Its main aim is a search for warm-hot intergalactic medium with high-resolution X-ray spectroscopy of redshifted emission lines from OVII and OVIII ions. The superior energy resolution of TES microcalorimeters combined with a very wide field of view (30-50 arcmin diameter) will enable us to look into gas dynamics of cosmic plasmas in a wide range of spatial scales from Earth™s magnetosphere to unvirialized regions of clusters of galaxies. Mechanical and thermal design of the spacecraft and development of the TES calorimeter system are described. We also consider revising the payload design to optimize the scientific capability allowed by the boundary conditions of the small mission.

      DOI: 10.1117/12.2055731

      Scopus

      researchmap

    • DIOS: the dark baryon exploring mission

      T. Ohashi, Y. Ishisaki, Y. Ezoe, S. Yamada, S. Yamaguchi, N. Miyazaki, Y. Tawara, K. Mitsuda, N. Y. Yamasaki, Y. Takei, K. Sakai, K. Nagayoshi, R. Yamamoto, A. Chiba, T. Hayashi

      SPACE TELESCOPES AND INSTRUMENTATION 2014: ULTRAVIOLET TO GAMMA RAY9144   2014年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:SPIE-INT SOC OPTICAL ENGINEERING  

      DIOS (Diffuse Intergalactic Oxygen Surveyor) is a small satellite aiming for a launch around 2020 with JAXA's Epsilon rocket. Its main aim is a search for warm-hot intergalactic medium with high-resolution X-ray spectroscopy of redshifted emission lines from OVII and OVIII ions. The superior energy resolution of TES microcalorimeters combined with a very wide field of view (30-50 arcmin diameter) will enable us to look into gas dynamics of cosmic plasmas in a wide range of spatial scales from Earth's magnetosphere to unvirialized regions of clusters of galaxies. Mechanical and thermal design of the spacecraft and development of the TES calorimeter system are described. We also consider revising the payload design to optimize the scientific capability allowed by the boundary conditions of the small mission.

      DOI: 10.1117/12.2055731

      Scopus

      researchmap

    • Soft x-ray spectrometer (SXS): The high-resolution cryogenic spectrometer onboard ASTRO-H 査読有り

      Kazuhisa Mitsuda, Richard L. Kelley, Hiroki Akamatsu, Thomas Bialas, Kevin R. Boyce, Gregory V. Brown, Edgar Canavan, Meng Chiao, Elisa Costantini, Jan-Willem Den Herder, Cor De Vries, Michael J. Dipirro, Megan E. Eckart, Yuichiro Ezoe, Ryuichi Fujimoto, Daniel Haas, Akio Hoshino, Kumi Ishikawa, Yoshitaka Ishisaki, Naoko Iyomoto, Caroline A. Kilbourne, Mark Kimball, Shunji Kitamoto, Saori Konami, Maurice A. Leutenegger, Dan McCammon, Joseph Miko, Ikuyuki Mitsuishi, Hiroshi Murakami, Masahide Murakami, Hirofumi Noda, Mina Ogawa, Takaya Ohashi, Atsushi Okamoto, Naomi Ota, Stéphane Paltani, F. Scott Porter, Kosuke Sato, Yoichi Sato, Makoto Sawada, Hiromi Seta, Keisuke Shinozaki, Peter J. Shirron, Gary A. Sneiderman, Hiroyuki Sugita, Andrew Szymkowiak, Yoh Takei, Toru Tamagawa, Makoto S. Tashiro, Yukikatsu Terada, Masahiro Tsujimoto, Shinya Yamada, Noriko Y. Yamasaki

      Proceedings of SPIE - The International Society for Optical Engineering9144   2014年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:SPIE  

      We present the development status of the Soft X-ray Spectrometer (SXS) onboard the ASTRO-H mission. The SXS provides the capability of high energy-resolution X-ray spectroscopy of a FWHM energy resolution of &lt
      7eV in the energy range of 0.3 - 10 keV. It utilizes an X-ray micorcalorimeter array operated at 50 mK. The SXS microcalorimeter subsystem is being developed in an EM-FM approach. The EM SXS cryostat was developed and fully tested and, although the design was generally confirmed, several anomalies and problems were found. Among them is the interference of the detector with the micro-vibrations from the mechanical coolers, which is the most difficult one to solve. We have pursued three different countermeasures and two of them seem to be effective. So far we have obtained energy resolutions satisfying the requirement with the FM cryostat.

      DOI: 10.1117/12.2057199

      Scopus

      researchmap

    • The New Primary Radiation from Seyfert 1 AGNs

      Miyake K, Noda H, Yamada S, Makishima K

      Suzaku-MAXI 2014: Expanding the Frontiers of the X-ray Universe, proceesdings of conference held 19-22 February   2014年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

      researchmap

    • Evidence for a cool disk and inhomogeneous coronae from wide-band temporal spectroscopy of cygnus X-1 with suzaku 査読有り

      Shin'ya Yamada, Kazuo Makishima, Chris Done, Shunsuke Torii, Hirofumi Noda, Soki Sakurai

      Publications of the Astronomical Society of Japan65 ( 4 ) 80   2013年8月25日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Oxford University Press  

      Unified X-ray spectral and timing studies of Cygnus X-1 in the low/hard and hard intermediate state were conducted in a model-independent manner, using broadband Suzaku data acquired on 25 occasions from 2005 to 2009 with a total exposure of ̃450 ks. The unabsorbed 0.1-500 keV source luminosity changed over 0.8%-2.8% of the Eddington limit for 14.8 solar masses. Variations on short (1-2 seconds) and long (days to months) time scales require at least three separate components: a constant component localized below ̃2 keV, a broad soft one dominating in the 2-10 keV range, and a hard one mostly seen in the 10-300 keV range. In view of the truncated disk/hot inner-flow picture, these are respectively interpreted as emission from the truncated cool disk, a soft Compton component, and a hard Compton component. Long-term spectral evolution can be produced by the constant disk increasing in temperature and luminosity as the truncation radius decreases. The soft Compton component likewise increases, but the hard Compton does not, so that the spectrum in the hard intermediate state is dominated by the soft Compton component
      on the other hand, the hard Compton component dominates the spectrum in the dim low/hard state, probably associated with a variable soft emission providing seed photons for the Comptonization. © 2013. Astronomical Society of Japan.

      DOI: 10.1093/pasj/65.4.80

      Scopus

      researchmap

    • REFLECTION-DOMINATED NUCLEAR X-RAY EMISSION IN THE EARLY-TYPE GALAXY ESO 565-G019 査読有り

      P. Gandhi, Y. Terashima, S. Yamada, R. F. Mushotzky, Y. Ueda, W. H. Baumgartner, D. M. Alexander, J. Malzac, K. Vaghmare, T. Takahashi, C. Done

      ASTROPHYSICAL JOURNAL773 ( 1 ) 51   2013年8月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      We present the discovery of a reflection-dominated active galactic nucleus (AGN) in the early-type radio-quiet galaxy ESO 565-G019 with Suzaku and Swift/Burst Alert Telescope. The source X-ray spectrum below 10 keV is characteristic of other Compton-thick (CT) AGNs, clearly showing an inverted continuum and prodigious fluorescence iron emission above similar to 3 keV. A Compton shoulder to the neutral Fe K alpha line also appears to be present. There is evidence for long-term hard X-ray flux variability that we associate with changes in the intrinsic AGN power law. More of such reflection-dominated AGNs should be uncovered in the near future with the increased sensitivity of ongoing and new hard X-ray surveys. ESO 565-G019 is hosted in an early-type galaxy whose morphology has been variously classified as either type E or type S0. Only about 20 bona fide CT-AGNs have been identified in the local universe so far, and all exist in host galaxies with late Hubble types (S0 or later). CT columns of nuclear obscuring gas are uncommon in early-type galaxies in the local universe, so confirmation of the exact morphological class of ESO 565-G019 is important. Infrared photometry also shows the presence of large quantities of cool dust in the host, indicative of significant ongoing star formation. ESO 565-G019 may be the first identified local example of minor-merger-driven CT-AGN growth in an early-type host, or may be the result of interaction with its neighboring galaxy ESO 565-G018 in a wide pair.

      DOI: 10.1088/0004-637X/773/1/51

      researchmap

    • Spectral Variation of Hard X-Ray Emission from the Crab Nebula with the Suzaku Hard X-Ray Detector 査読有り

      Tomomi Kouzu, Makoto S. Tashiro, Yukikatsu Terada, Shin'ya Yamada, Aya Bamba, Teruaki Enoto, Koji Mori, Yasushi Fukazawa, Kazuo Makishima

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN65 ( 4 ) 74   2013年8月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      The Crab Nebula is one of the brightest and most stable sources in the X-ray sky. Year-scale flux variation from the object was recently revealed in the hard X-ray band by four satellites. This marked the first detection of year-scale variability from pulsar wind nebulae in the hard X-ray band. The Crab Nebula has been observed at least once a year for calibration purposes with the Suzaku Hard X-ray Detector (HXD) since its launch in 2005. In order to investigate possible spectral changes as well as flux variation, archival data of the HXD were analyzed. The flux variation reported by other instruments was confirmed in the 25-100 keV band by the HXD at a few percent level, but flux above 100 keV did not follow the trend in variation below 100 keV. The hardness ratios produced utilizing the PIN and GSO sensors installed in the HXD exhibit significant scattering, thereby indicating spectral variations in the hard X-ray band. The spectral changes were quantified by spectral fitting with a broken power-law model. The difference between the two photon indexes of the broken power-law model in harder and softer energy bands is in the range of < 2.54. Taking into account a flux variation of 6.3% and a spectral variation time-scale of a few days, multi components of the broken power-law-shaped synchrotron emission with different cooling times are suggested.

      DOI: 10.1093/pasj/65.4.74

      researchmap

    • Hardening and termination of long-duration γ rays detected prior to lightning 査読有り

      H. Tsuchiya, T. Enoto, K. Iwata, S. Yamada, T. Yuasa, T. Kitaguchi, M. Kawaharada, K. Nakazawa, M. Kokubun, H. Kato, M. Okano, T. Tamagawa, K. Makishima

      Physical Review Letters111 ( 1 ) 015001   2013年7月1日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)  

      We report the first observation of 3-30 MeV prolonged gamma-ray emission that was abruptly terminated by lightning. The gamma-ray detection was made during winter thunderstorms on December 30, 2010, by the Gamma-Ray Observation of Winter Thunderclouds experiment carried out in a coastal area along the Sea of Japan. The gamma-ray flux lasted for less than 3 min, continuously hardening closer to the lightning occurrence. The hardening at energies of 3-10 MeV energies was most prominent. The gamma-ray flux abruptly ceased less than 800 ms before the lightning flash that occurred over 5 km away from the experimental site. In addition, we observed a clear difference in the duration of the 3-10 MeV gamma rays and those &gt
      10 MeV, suggesting that the area of &gt
      10 MeV gamma-ray emission is considerably smaller than that of the lower-energy gamma rays. This work may give a manifestation that a local region emitting prolonged gamma rays connects with a distant region to initiate lightning. © 2013 American Physical Society.

      DOI: 10.1103/PhysRevLett.111.015001

      Scopus

      researchmap

    • A SUZAKU DISCOVERY OF A SLOWLY VARYING HARD X-RAY CONTINUUM FROM THE TYPE I SEYFERT GALAXY NGC 3516 査読有り

      Hirofumi Noda, Kazuo Makishima, Kazuhiro Nakazawa, Shin'ya Yamada

      ASTROPHYSICAL JOURNAL771 ( 2 ) 100   2013年7月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      The bright type I Seyfert galaxy NGC 3516 was observed by Suzaku twice, in 2005 October 12-15 and 2009 October 28-November 2, for a gross time coverage of 242 and 544 ks and a net exposure of 134 and 255 ks, respectively. The 2-10 keV luminosity was 2.8x10(41) erg s(-1) in 2005 and 1.6x10(41) erg s(-1) in 2009. The 1.4-1.7 keV and 1.7-10 keV count rates both exhibited peak-to-peak variations of a factor of similar to 2 in 2005 and similar to 4 in 2009. In both observations, the 15-45 keV count rate was less variable. The 2-10 keV spectrum in 2005 was significantly more convex than that in 2009. Through a count-count plot technique, the 2-45 keV signals in both sets of data were successfully decomposed in a model-independent way into two distinct broadband components. One is a variable emission with a featureless spectral shape, and the other is a non-varying hard component accompanied by a prominent Fe-K emission line at 6.33 keV (6.40 keV in the rest frame). The former was successfully fitted by an absorbed power-law model, while the latter requires a new hard continuum in addition to a reflection component from distant materials. The spectral and variability differences between the two observations are mainly attributed to long-term changes of this new hard continuum, which was stable on timescales of several hundreds of kiloseconds.

      DOI: 10.1088/0004-637X/771/2/100

      researchmap

    • Suzaku Follow-Up Observation of the Activated Magnetar 1E 1547.0-5408 査読有り

      Takanori Iwahashi, Teruaki Enoto, Shin'ya Yamada, Hiroyuki Nishioka, Kazuhiro Nakazawa, Toru Tamagawa, Kazuo Makishima

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN65 ( 3 ) 52   2013年6月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      We present broadband X-ray analyses of the magnetar 1E 1547.0-5408 observed with Suzaku on 2010 August 7, nearly one and a half years after an intense outburst in 2009 January. The 2-10 keV flux decreased to (1.06 +/- 0.01) x 10(-11) erg cm(-2) s(-1), while the hard X-ray detection was 3.5 sigma (18-40 keV) and 2.4 sigma (18-35 keV) significance levels, where the former includes only the 2% systematic error of the non X-ray background, and the latter further takes into account possible near-by contaminating sources, respectively. Our confirmation of both soft and hard X-ray components during the late phase of the outburst strengthened the possibility that most magnetars are composed of the two spectral components, both in burst-active and less-active states. Together with a similar decay speed between the soft and hard components, their radiation mechanisms are suggested to be tightly related to each other. The 1-40 keV broadband spectrum was successfully fitted with the same model as used in the fit just after the onset of the outburst in 2009: a surface blackbody radiation with photoelectric absorption and a hard power-law. The blackbody flux decreased to be similar to 30% of that in 2009 while keeping its temperature at kT = 0.65 keV, suggesting a shrinking hotspot on the magnetar surface by a factor of 0.3. The hard power-law extended up to at least similar to 35 keV with a photon index of Gamma = 1.1 +/- 0.4, which was consistent with the 2009 value. The flux ratio, xi, of the 1-60 keV power-law to 1-60 keV thermal component was calculated to be xi = 1.2 +/- 0.7 at the late phase of the outburst for the first time. The obtained value follows the previously known negative correlation with the characteristic age, implying that the correlation holds for most of the magnetar states: no burst, onset and late phase of outbursts.

      DOI: 10.1093/pasj/65.3.52

      researchmap

    • HIGHLY IONIZED Fe-K ABSORPTION LINE FROM CYGNUS X-1 IN THE HIGH/SOFT STATE OBSERVED WITH SUZAKU 査読有り

      S. Yamada, S. Torii, S. Mineshige, Y. Ueda, A. Kubota, P. Gandhi, C. Done, H. Noda, A. Yoshikawa, K. Makishima

      ASTROPHYSICAL JOURNAL LETTERS767 ( 2 ) L35   2013年4月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      We present observations of a transient He-like Fe Ka absorption line in Suzaku observations of the black hole binary Cygnus X-1 on 2011 October 5 near superior conjunction during the high/soft state, which enable us to map the full evolution from the start to the end of the episodic accretion phenomena or dips for the first time. We model the X-ray spectra during the event and trace their evolution. The absorption line is rather weak in the first half of the observation, but instantly deepens for similar to 10 ks, and weakens thereafter. The overall change in equivalent width is a factor of similar to 3, peaking at an orbital phase of similar to 0.08. This is evidence that the companion stellar wind feeding the black hole is clumpy. By analyzing the line with a Voigt profile, it is found to be consistent with a slightly redshifted Fe xxv transition, or possibly a mixture of several species less ionized than Fe xxv. The data may be explained by a clump located at a distance of similar to 10(10-12) cm with a density of similar to 10((-13)-(-11)) g cm(-3), which accretes onto and/or transits the line of sight to the black hole, causing an instant decrease in the observed degree of ionization and/or an increase in density of the accreting matter. Continued monitoring for individual events with future X-ray calorimeter missions such as ASTRO-H and AXSIO will allow us to map out the accretion environment in detail and how it changes between the various accretion states.

      DOI: 10.1088/2041-8205/767/2/L35

      researchmap

    • RAPID SPECTRAL CHANGES OF CYGNUS X-1 IN THE LOW/HARD STATE WITH SUZAKU 査読有り

      S. Yamada, H. Negoro, S. Torii, H. Noda, S. Mineshige, K. Makishima

      ASTROPHYSICAL JOURNAL LETTERS767 ( 2 ) L34   2013年4月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      Rapid spectral changes in the hard X-ray on a timescale down to similar to 0.1 s are studied by applying a "shot analysis" technique to the Suzaku observations of the black hole binary Cygnus X-1, performed on 2008 April 18 during the low/hard state. We successfully obtained the shot profiles, covering 10-200 keV with the Suzaku HXD-PIN and HXD-GSO detector. It is notable that the 100-200 keV shot profile is acquired for the first time owing to the HXD-GSO detector. The intensity changes in a time-symmetric way, though the hardness changes in a time-asymmetric way. When the shot-phase-resolved spectra are quantified with the Compton model, the Compton y-parameter and the electron temperature are found to decrease gradually through the rising phase of the shot, while the optical depth appears to increase. All the parameters return to their time-averaged values immediately within 0.1 s past the shot peak. We have not only confirmed this feature previously found in energies below similar to 60 keV, but also found that the spectral change is more prominent in energies above similar to 100 keV, implying the existence of some instant mechanism for direct entropy production. We discuss possible interpretations of the rapid spectral changes in the hard X-ray band.

      DOI: 10.1088/2041-8205/767/2/L34

      researchmap

    • The nature of stable soft X-ray emissions in several types of active galactic nuclei observed by Suzaku 査読有り

      Hirofumi Noda, Kazuo Makishima, Kazuhiro Nakazawa, Hideki Uchiyama, Shin'Ya Yamada, Soki Sakurai

      Publications of the Astronomical Society of Japan65 ( 1 ) 4   2013年2月25日

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Oxford University Press  

      To constrain the origin of the soft X-ray excess phenomenon seen in many active galactic nuclei, the intensity-correlated spectral analysis, developed by Noda et al. (2011, PASJ, 63, S925) for Markarian 509, was applied to wideband (0.5-45 keV) Suzaku data of five representative objects with a relatively weak reflection signature. They are the typical bare-nucleus type 1 Seyfert Fairall 9, the bright and typical type 1.5 Seyfert MCG-2-58-22, 3C 382, which is one of the X-ray brightest broad line radio galaxies, the typical Seyfert-like radio loud quasar 4C+74.26, and the X-ray brightest radio quiet quasar MR 2251-178. In all of them, soft X-ray intensities in energies below 3 keV were tightly correlated with that in 3-10 keV, but with significant positive offsets. These offsets, when calculated in finer energy bands, define a stable soft component in 0.5-3 keV. In each object, this component successfully explained the soft excess above a power-law fit. These components were interpreted in several alternative ways, including a thermal Comptonization component that is independent of the dominant power-law emission. This interpretation, considered physically most reasonable, is discussed from a viewpoint of Multi-Zone Comptonization, which was proposed for the black hole binary Cygnus X-1 (Makishima et al. 2008, PASJ, 60, 585). © 2013. Astronomical Society of Japan.

      DOI: 10.1093/pasj/65.1.4

      Scopus

      researchmap

    • Development of superconducting multilayer wiring for a 400-Pixel TES x-ray microcalorimeter array

      Yuichiro Ezoe, Shihoko Oishi, Shinya Yamada, Yosuke Enokijima, Noriko Iijima, Reina Toba, Yoshitaka Ishisaki, Takaya Ohashi, Kazuhisa Mitsuda, Toshimitsu Morooka, Keiichi Tanaka

      IEEE Transactions on Applied Superconductivity23 ( 3 )   2013年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)  

      Aiming at a large array of transition edge sensors for future astrophysical missions such as DIOS, we have been developing a multilayer readout wiring. Superconducting signal and return lines made of Al sandwich a SiO2 insulation layer. With this approach, self and mutual inductances are minimized and self fielding of bias leads can be reduced. We fabricated a 20 × 20 transition-edge sensor (TES) array on the multilayer wiring. A series of TES fabrication processes including absorber deposition and membrane formation were tested. However, resistance measurements at room temperature suggest that process yield is not high ( ∼50 %). At low temperature, sharp superconducting transitions were observed for normal TES pixels, while their residual resistances were high (&gt
      10mΩ) and the critical currents were low (&lt
      10mu
      A). Reasons for these phenomena and plans for a future TES array fabrication are discussed. © 2002-2011 IEEE.

      DOI: 10.1109/TASC.2012.2231712

      Scopus

      researchmap

    • Geometry dependence of the light collection efficiency of BGO crystal scintillators read out by avalanche photo diodes 査読有り

      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 Equipment715   105 - 111   2013年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:ELSEVIER SCIENCE BV  

      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: 10.1016/j.nima.2013.03.022

      Scopus

      researchmap

    • Model-Independent Decomposition of Broad-Band Suzaku Spectra of AGNs into Primary and Secondary Components

      Noda H, Makishima K, Nakazawa K, Yamada S

      Memorie della Societa Astronomica Italiana ( 84 ) 707   2013年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

      researchmap

    • HIGH-RESOLUTION X-RAY SPECTROSCOPY OF THE GALACTIC SUPERNOVA REMNANT PUPPIS A WITH XMM-NEWTON/RGS 査読有り

      Satoru Katsuda, Hiroshi Tsunemi, Koji Mori, Hiroyuki Uchida, Robert Petre, Shin'ya Yamada, Hiroki Akamatsu, Saori Konami, Toru Tamagawa

      ASTROPHYSICAL JOURNAL756 ( 1 ) 49   2012年9月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      We present high-resolution X-ray spectra of cloud-shock interaction regions in the eastern and northern rims of the Galactic supernova remnant Puppis A, using the Reflection Grating Spectrometer on board the XMM-Newton satellite. A number of emission lines including K alpha triplets of He-like N, O, and Ne are clearly resolved for the first time. Intensity ratios of forbidden to resonance lines in the triplets are found to be higher than predictions by thermal emission models having plausible plasma parameters. The anomalous line ratios cannot be reproduced by effects of resonance scattering, recombination, or inner-shell ionization processes, but could be explained by charge-exchange emission that should arise at interfaces between the cold/warm clouds and the hot plasma. Our observations thus provide observational support for charge-exchange X-ray emission in supernova remnants.

      DOI: 10.1088/0004-637X/756/1/49

      researchmap

    • Accretion Geometry of the Low-Mass X-Ray Binary Aquila X-1 in the Soft and Hard States 査読有り

      Soki Sakurai, Shin'ya Yamada, Shunsuke Torii, Hirofumi Noda, Kazuhiro Nakazawa, Kazuo Makishima, Hiromitsu Takahashi

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN64 ( 4 ) 72   2012年8月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      The neutron-star Low-Mass X-ray Binary Aquila X-1 was observed seven times in total with the Suzaku X-ray observatory from September 28 to October 30 in 2007, in the decaying phase of an outburst. In order to constrain the flux-dependent accretion geometry of this source over wider energy bands than employed in most previous studies, the present study utilized two out of seven data sets. The 0.8-31 keV spectrum on September 28, taken with the XIS and HXD-PIN for an exposure of 13.8 ks, shows an absorbed 0.8-31 keV flux of 3.6 x 10(-9) erg s(-1) cm(-2), together with typical characteristics of the soft state of this type of object. The spectrum was successfully explained by an optically thick disk emission plus a Comptonized blackbody component. Although these results are in general agreement with previous studies, the significance of a hard tail recently reported using the same data was inconclusive in our analysis. The spectrum acquired on October 9 for an exposure of 19.7 ks was detected over a 0.8-100 keV band with the XIS, HXD-PIN, and HXD-GSO, at an absorbed flux of 8.5 x 10(-10) erg s(-1) cm(-2) (in 0.8-100 keV). It shows characteristics of the hard state, and was successfully explained by the same two continuum components, but with rather different parameters, including much stronger thermal Comptonization, of which the seed photon source was identified with blackbody emission from the neutron-star surface. As a result, the accretion flow in the hard state is inferred to take the form of an optically-thick and geometrically-thin disk down to a radius of 21 +/- 4 km from the neutron star, and then turn into an optically thin nearly spherical hot flow.

      DOI: 10.1093/pasj/64.4.72

      researchmap

    • DISCOVERY OF A PULSAR WIND NEBULA CANDIDATE IN THE CYGNUS LOOP 査読有り

      Satoru Katsuda, Hiroshi Tsunemi, Koji Mori, Hiroyuki Uchida, Robert Petre, Shin'ya Yamada, Toru Tamagawa

      ASTROPHYSICAL JOURNAL LETTERS754 ( 1 ) L7   2012年7月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      We report on a discovery of a diffuse nebula containing a pointlike source in the southern blowout region of the Cygnus Loop supernova remnant, based on Suzaku and XMM-Newton observations. The X-ray spectra from the nebula and the pointlike source are well represented by an absorbed power-law model with photon indices of 2.2 +/- 0.1 and 1.6 +/- 0.2, respectively. The photon indices as well as the flux ratio of F-nebula/F-pointlike similar to 4 lead us to propose that the system is a pulsar wind nebula, although pulsations have not yet been detected. If we attribute its origin to the Cygnus Loop supernova, then the 0.5-8 keV luminosity of the nebula is computed to be 2.1 x 10(31) (d/540 pc)(2) erg s(-1), where d is the distance to the Loop. This implies a spin-down loss-energy E. similar to 2.6 x 10(35) (d/540 pc)(2) erg s(-1). The location of the neutron star candidate, similar to 2 degrees away from the geometric center of the Loop, implies a high transverse velocity of similar to 1850 (theta/2 degrees) (d/540 pc) (t/10 kyr)(-1) km s(-1), assuming the currently accepted age of the Cygnus Loop.

      DOI: 10.1088/2041-8205/754/1/L7

      researchmap

    • THE TRUNCATED DISK FROM SUZAKU DATA OF GX 339-4 IN THE EXTREME VERY HIGH STATE 査読有り

      Manami Tamura, Aya Kubota, Shinya Yamada, Chris Done, Mari Kolehmainen, Yoshihiro Ueda, Shunsuke Torii

      ASTROPHYSICAL JOURNAL753 ( 1 ) 65   2012年7月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      We report on the geometry of accretion disk and high-energy coronae in the strong Comptonization state (the very high/steep power law/hard intermediate state) based on a Suzaku observation of the famous Galactic black hole GX 339-4. These data were taken just before the peak of the 2006-2007 outburst, and the average X-ray luminosity in the 0.7-200 keV band is estimated to be 2.9 x 10(38) erg s(-1) for a distance of 8 kpc. We fit the spectrum with both simple (independent disk and corona) and sophisticated (energetically coupled disk and corona) models; all fits imply that the underlying optically thick disk is truncated significantly before the innermost stable circular orbit around the black hole. We show this directly by a comparison with similar broadband data from a disk-dominated spectrum at almost the same luminosity observed by XMM-Newton and RXTE 3 days after the Suzaku observation. During the Suzaku observation, the quasi-periodic oscillation (QPO) frequency changes from 4.3 Hz to 5.5 Hz, while the spectrum softens. The energetically coupled model gives a corresponding 5%+/- 8% decrease in the derived inner radius of the disk. While this is not significant, it is consistent with the predicted change in QPO frequency from the Lense-Thirring precession of the hot flow interior to the disk and/or a deformation mode of this flow, as a higher QPO frequency implies a smaller size scale for the corona. This is consistent with the truncated disk extending further inward toward the black hole.

      DOI: 10.1088/0004-637X/753/1/65

      researchmap

    • Data-Oriented Diagnostics of Pileup Effects on the Suzaku XIS 査読有り

      Shin'ya Yamada, Hideki Uchiyama, Tadayasu Dotani, Masahiro Tsujimoto, Satoru Katsuda, Kazuo Makishima, Hiromitsu Takahashi, Hirofumi Noda, Shunsuke Torii, Soki Sakurai, Teruaki Enoto, Takayuki Yuasa, Shu Koyama, Aya Bamba

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN64 ( 3 ) 53   2012年6月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      We present the results of a systematic study of pileup phenomena seen in the X-ray Imaging Spectrometer, an X-ray CCD instrument, onboard the Suzaku observatory. Using a data set of observed sources in a wide range of brightness and spectral hardness, we characterized the pileup fraction, spectral hardening, and grade migration as a function of the observed count rate in a frame per pixel. Using the pileup fraction as a measure of the degree of pileup, we found that the relative spectral hardening (the hardness ratio normalized to the intrinsic spectral hardness), branching ratio of split events, and that of detached events increase monotonically as the pileup fraction increases, despite the variety of brightness and hardness of the sample sources. We derived the pileup fraction as a function of radius used for event extraction. Upon practical considerations, we found that events outside of the radius with a pileup fraction of 1% or 3% are useful for spectral analysis. We present relevant figures, tables, and software for the convenience of users who wish to apply our method for their data reduction of piled-up sources.

      DOI: 10.1093/pasj/64.3.53

      researchmap

    • POSSIBLE DETECTION OF AN EMISSION CYCLOTRON RESONANCE SCATTERING FEATURE FROM THE ACCRETION-POWERED PULSAR 4U 1626-67 査読有り

      W. B. Iwakiri, Y. Terada, T. Mihara, L. Angelini, M. S. Tashiro, T. Enoto, S. Yamada, K. Makishima, M. Nakajima, A. Yoshida

      ASTROPHYSICAL JOURNAL751 ( 1 ) 35   2012年5月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      We present analysis of 4U 1626-67, a 7.7 s pulsar in a low-mass X-ray binary system, observed with the hard X-ray detector of the Japanese X-ray satellite Suzaku in 2006 March for a net exposure of similar to 88 ks. The source was detected at an average 10-60 keV flux of similar to 4 x 10(-10) erg cm(-2) s(-1). The phase-averaged spectrum is reproduced well by combining a negative and positive power-law times exponential cutoff (NPEX) model modified at similar to 37 keV by a cyclotron resonance scattering feature (CRSF). The phase-resolved analysis shows that the spectra at the bright phases are well fit by the NPEX with CRSF model. On the other hand, the spectrum in the dim phase lacks the NPEX high-energy cutoff component, and the CRSF can be reproduced by either an emission or an absorption profile. When fitting the dim phase spectrum with the NPEX plus Gaussian model, we find that the feature is better described in terms of an emission rather than an absorption profile. The statistical significance of this result, evaluated by means of an F test, is between 2.91 x 10(-3) and 1.53 x 10(-5), taking into account the systematic errors in the background evaluation of HXD-PIN. We find that the emission profile is more feasible than the absorption one for comparing the physical parameters in other phases. Therefore, we have possibly detected an emission line at the cyclotron resonance energy in the dim phase.

      DOI: 10.1088/0004-637X/751/1/35

      researchmap

    • A spectral study of the black hole candidate XTE J1752-223 in the high/soft state with MAXI, Suzaku, and Swift 査読有り

      Satoshi Nakahira, Shu Koyama, Yoshihiro Ueda, Kazutaka Yamaoka, Mutsumi Sugizaki, Tatehiro Mihara, Masaru Matsuoka, Atsumasa Yoshida, Kazuo Makishima, Ken Ebisawa, Aya Kubota, Shin'ya Yamada, Hitoshi Negoro, Kazuo Hiroi, Masaki Ishikawa, Nobuyuki Kawai, Masashi Kimura, Hiroki Kitayama, Mitsuhiro Kohama, Takanori Matsumura, Mikio Morii, Motoki Nakajima, Motoko Serino, Megumi Shidatsu, Tetsuya Sootome, Kousuke Sugimori, Fumitoshi Suwa, Hiroshi Tomida, Yoko Tsuboi, Hiroshi Tsunemi, Shiro Ueno, Ryuichi Usui, Takayuki Yamamoto, Kyohei Yamazaki, Makoto S. Tashiro, Yukikatsu Terada, Hiromi Seta

      Publications of the Astronomical Society of Japan64 ( 1 ) 13   2012年2月25日

      詳細を見る

      掲載種別:研究論文(学術雑誌)  

      We report on an X-ray spectral analysis of the black hole candidate XTE J1752-223 in the 2009-2010 outburst, utilizing data obtained with the MAXI/Gas Slit Camera (GSC), the Swift/XRT, and Suzaku, which work comple-mentarily. As already reported by Nakahira et al. (2010, PASJ, 62, L27), MAXI monitored the source continuously throughout the entire outburst for about eight months. All of the MAXI/GSC energy spectra in the high/soft state, lasting for 2 months, are well represented by a multi-color disk plus power-law model. The innermost disk temperature changed from ∼0.7 keV to ∼0.4 keV and the disk flux decreased by an order of magnitude. Nevertheless, the innermost radius is constant at ∼41 D 3.5 (cos i) -1/2 km, where D 3.5 is the source distance in units of 3.5kpc and i the inclination. The multi-color disk parameters obtained with the MAXI/GSC are consistent with those with the Swift/XRT and Suzaku. The Suzaku data also suggest a possibility that the disk emission is slightly Comptonized, which could account for broad iron-K features reported previously. Assuming that the obtained innermost radius represents the innermost stable circular orbit for a non-rotating black hole, we estimate the mass of the black hole to be 5.51 ± 0.28 M ⊙ D 3.5 (cos -1/2 , where the correction for the stress-free inner boundary condition and color hardening factor of 1.7 are taken into account. If the inclination is less than 49°, as suggested from radio monitoring of transient jets, and the soft-to-hard transition in 2010 April occurred at 1%-4% of Eddignton luminosity, the fitting of the Suzaku spectra with a relativistic accretion-disk model derives constraints on the mass and the distance to be 3.1-55M ⊙ and 2.3-22 kpc, respectively. This confirms that the compact object in XTE J1752-223 is a black hole. © 2012. Astronomical Society of Japan.

      DOI: 10.1093/pasj/64.1.13

      Scopus

      researchmap

    • Broad-band Suzaku spectra of the LMXB Aql X-1 in the soft and hard states 査読有り

      Soki Sakurai, Shin'ya Yamada, Kazuhiro Nakazawa, Kazuo Makishima

      SUZAKU 2011: EXPLORING THE X-RAY UNIVERSE: SUZAKU AND BEYOND1427   2012年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:AMER INST PHYSICS  

      Aiming at understanding the soft and hard states of accreting weak-field neutron stars, archival Suzaku data of the recurrent transient Aql X-1, taken during a 2007 outburst, were analyzed. In one data set, where the object was in the soft state, the 1-30 keV spectrum was reproduced by a disk blackbody plus a Comptonized blackbody components, which is consistent with previous studies. Other three data sets were taken during the typical hard state, with a factor similar to 6 lower luminosity than the first one. The source was detected up to similar to 100 keV on these occasions, and the wide-band spectra were reproduced by the same model composition as the soft state, but with much stronger Comptonization and a larger disk radii. The three hard-state spectra exhibited comparable luminosities, and gave similar model parameters. Therefore, the spectrum of this source is considered to be determined rather uniquely by the mass accretion rate.

      DOI: 10.1063/1.3696217

      researchmap

    • Hard X-ray properties of a variable standard candle, Crab, with the Suzaku/HXD

      T. Kouzu, Y. Terada, M. S. Tashiro, S. Yamada, A. Bamba, T. Yuasa, K. Mori, Y. Fukazawa, T. Enoto, Y. T. Tanaka, S. Shibata, K. Makishima

      AIP Conference Proceedings1427   265 - 266   2012年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:AIP Conference Proceedings  

      The Crab Nebula had been believed to be a stable standard candle for historical X-ray instruments for many years. Recently it was found that a hard X-ray flux (15-100 keV) of Crab Nebula fluctuated by 10 over 10 years. The origin of the long-term variation is still unclear, but the nature of the Crab Nebula is now hot topic both on science and hardware developments. The HXD onboard Suzaku has the highest sensitivity in the 10-600 keV band. Hence it is useful to search for flux variations and possible spectral changes. We performed systematic studies on Crab X-ray spectra in the 10-600 keV band with the HXD, by using 12 observations of Crab until 2010. In this paper, we summarized a hard X-ray study of Crab with the HXD. © 2012 American Institute of Physics.

      DOI: 10.1063/1.3696196

      Scopus

      researchmap

    • Soft Gamma-ray Detector for the ASTRO-H mission 査読有り

      Shin Watanabe, Hiroyasu Talima, Yasushi Fukazawa, Roger Blandford, Teruaki Enoto, Jun Kataoka, Madoka Kawaharada, Motohide Kokubun, Philippe Laurent, Francois Lebrun, Olivier Limousin, Greg Madejski, Kazuo Makishima, Tsunefumi Mizuno, Takeshi Nakamori, Kazuhiro Nakazawa, Kunishiro Mori, Hirokazu Odaka, Masanori Ohno, Masayuki Ohta, Goro Sato, Rie Sato, Shin'ichiro Takeda, Hiromitsu Takahashi, Tadayuki Takahashi, Takaaki Tanaka, Makoto Tashiro, Yukikatsu Terada, Hideki Uchiyama, Yasunobu Uchiyama, Shinya Yamada, Yoichi Yatsu, Daisuke Yonetoku, Takayuki Yuasa

      SPACE TELESCOPES AND INSTRUMENTATION 2012: ULTRAVIOLET TO GAMMA RAY8443   2012年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:SPIE-INT SOC OPTICAL ENGINEERING  

      ASTRO-H is the next generation JAXA X-ray satellite, intended to carry instruments with broad energy coverage and exquisite energy resolution. The Soft Gamma-ray Detector (SGD) is one of ASTRO-H instruments and will feature wide energy band (60-600 keV) at a background level 10 times better than the current instruments on orbit. The SGD is complimentary to ASTRO-H's Hard X-ray Imager covering the energy range of 5-80 keV. The SGD achieves low background by combining a Compton camera scheme with a narrow field-of-view active shield where Compton kinematics is utilized to reject backgrounds. The Compton camera in the SGD is realized as a hybrid semiconductor detector system which consists of silicon and CdTe (cadmium telluride) sensors. Good energy resolution is afforded by semiconductor sensors, and it results in good background rejection capability due to better constraints on Compton kinematics. Utilization of Compton kinematics also makes the SGD sensitive to the gamma-ray polarization, opening up a new window to study properties of gamma-ray emission processes. In this paper, we will present the detailed design of the SGD and the results of the final prototype developments and evaluations. Moreover, we will also present expected performance based on the measurements with prototypes.

      DOI: 10.1117/12.925977

      researchmap

    • Status report of the hard x-ray detector 査読有り

      Shin'Ya Yamada

      AIP Conference Proceedings1427   111 - 114   2012年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

      The current status and the improvements of in-orbit calibration in the Hard X-ray Detector (HXD) on board Suzaku are presented. We have been extensively monitoring and calibrating the in-orbit HXD performance, and succeeded in keeping all the sensors working property without any significant troubles since the launch. To reduce the increasing thermal noise events due to radiation damage in the HXD-PIN, we have raised the analog/digital threshold levels and updated the corresponding responses of the PIN. Performing the calibration of the energy scale of the GSO, we have improved the accuracy of the energy scale and modeling of gain variations, and released the reprocessed data/background and the responses since April of 2010. These revised data of the GSO is usable down to 50 keV, consequently allowing us to utilize overlapping energy ranges of 50-70 keV between the PIN and the GSO. Based on these improvements, we have reproduced the HXD spectra of the Crab Nebula over 10-500 keV with the broken power law with a cutoff at about 120 keV. © 2012 American Institute of Physics.

      DOI: 10.1063/1.3696159

      Scopus

      researchmap

    • Suzaku Studies of SFXT Flare Mechanisms 査読有り

      M. Sasano, T. Yuasa, S. Yamada, K. Nakazawa, K. Makishima

      SUZAKU 2011: EXPLORING THE X-RAY UNIVERSE: SUZAKU AND BEYOND1427   2012年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:AMER INST PHYSICS  

      To understand flare mechanisms of SFXTs, we analyzed Suzaku public data of AXJ161929-4945. The data covered a large flare with a rise time of about 500 sec and a duration of about 3 hours. Over a 1-40 keV band, the spectra were very similar between the flare and quiescence periods. The column density was not different between the two spectra by more than 10%. A narrow Fe-line were very clearly detected in the quiescence, but disappeared in the flare. These results suggest that the flare occured due to strong magnetic fields of the neutron star.

      DOI: 10.1063/1.3696219

      researchmap

    • The Suzaku View of Cyg X-1 over the Two Spectral States 査読有り

      Shunsuke Torii, Kazuo Makishima, Shin'ya Yamada, Kazuhiro Nakazawa

      SUZAKU 2011: EXPLORING THE X-RAY UNIVERSE: SUZAKU AND BEYOND1427   2012年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:AMER INST PHYSICS  

      We conducted 25 Suzaku observations of Cyg X-1 in the Low/Hard State, with a total exposure of about 450 ks, Here, we analyzed the data from the Hard X-ray Detector (HXD). From results obtained from spectral and timing analysis, we derived some picture of evolution of the accretion flow in the Low/Hard State. and the cool disk to intrude more deeply therein (Torii et al. 2011). On 2010 December 16, a Suzaku ToO observation of Cyg X-1 was performed to benefit from the most recent High/Soft State found with MAXI. A brief analysis of the data is presented in this paper.

      DOI: 10.1063/1.3696163

      researchmap

    • The x-ray advanced concepts testbed (XACT) sounding rocket payload 査読有り

      Keith Gendreau, Zaven Arzoumanian, Fumi Asami, Robert Baker, Erin Balsamo, Kevin Black, Carlos Duran-Aviles, Teruaki Enoto, Kyle Gregory, Devin Hahne, Asami Hayato, Joe Hill, Fred Huegel, Takanori Iwahashi, Wataru Iwakiri, Keith Jahoda, Lalit Jalota, Philip Kaaret, Kenta Kaneko, Steven Kenyon, Takao Kitaguchi, Richard Koenecke, Takayoshi Kohmura, Takashi Okajima, Larry Olsen, F. Scott Porter, Kurt Rush, Peter Serlemitsos, Yang Soong, Yoko Takeuchi, Toru Tamagawa, Shin'ya Yamada, Akifumi Yoshikawa

      SPACE TELESCOPES AND INSTRUMENTATION 2012: ULTRAVIOLET TO GAMMA RAY8443   2012年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:SPIE-INT SOC OPTICAL ENGINEERING  

      The scientific objective of the X-ray Advanced Concepts Testbed (XACT) is to measure the X-ray polarization properties of the Crab Nebula, the Crab pulsar, and the accreting binary Her X-1. Polarimetry is a powerful tool for astrophysical investigation that has yet to be exploited in the X-ray band, where it promises unique insights into neutron stars, black holes, and other extreme-physics environments. With powerful new enabling technologies, XACT will demonstrate X-ray polarimetry as a practical and flight-ready astronomical technique. Additional technologies that XACT will bring to flight readiness will also provide new X-ray optics and calibration capabilities for NASA missions that pursue space-based X-ray spectroscopy, timing, and photometry.

      DOI: 10.1117/12.926418

      researchmap

    • Wide-band and intensity-related spectral analysis of Cygnus X-1 with Suzaku 査読有り

      Shin'Ya Yamada

      AIP Conference Proceedings1427   40 - 47   2012年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

      We analyzed Suzaku data of Cygnus X-1 in the low/hard state, acquired on 25 occasions from 2005 to 2009, over 0.5-300 keV with a total exposure of ∼450 ks. Among the observations, its luminosity changed by a factor of ∼3. We found two different types of spectral changes in rather model independent manners. One is an increase of variability in E &lt
      10 keV on time scales of days to months, revealed via a direct comparison among the 25 spectra. The other is a decrease of variability in E &lt
      2 keV on time scales of 1-2 seconds, derived by using intensity-correlated spectral changes for each observation. The two spectral changes can be understood by considering that the accretion flow consists of a cool disk with a temperature of ∼0.2 keV surrounded by inhomogeneous coronae. © 2012 American Institute of Physics.

      DOI: 10.1063/1.3696148

      Scopus

      researchmap

    • Improvements in Calibration of GSO Scintillators in the Suzaku Hard X-Ray Detector 査読有り

      Shin'ya Yamada, Kazuo Makishima, Kazuhiro Nakazawa, Motohide Kokubun, Madoka Kawaharada, Takao Kitaguchi, Shin Watanabe, Hiromitsu Takahashi, Hirofumi Noda, Hiroyuki Nishioka, Kazuyoshi Hiragi, Katsuhiro Hayashi, Kenta Nakajima, Makoto Tashiro, Makoto Sasano, Sho Nishino, Shunsuke Torii, Soki Sakurai, Tadayuki Takahashi, Tsunefumi Mizuno, Teruaki Enoto, Takayuki Yuasa, Takaaki Tanaka, Tomomi Kouzu, Toshio Nakano, Yasushi Fukazawa, Yukikatsu Terada, Yasunobu Uchiyama, Wataru Iwakiri

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN63   S645 - S656   2011年11月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      Improvements of the in-orbit calibration of GSO scintillators in the Hard X-ray Detector aboard Suzaku are reported. To resolve an apparent change in the energy scale of GSO, which appeared across the launch for unknown reasons, consistent and thorough re-analyses of both pre-launch and in-orbit data have been performed. With laboratory experiments using spare hardware, the pulse-height offset, corresponding to zero energy input, was found to change by similar to 0.5% of the full analog voltage scale, depending on the power supply. Furthermore, by carefully calculating all of the light outputs of secondaries from activation lines used in the in-orbit gain determination, their energy deposits in GSO were found to be effectively lower, by several percent, than their nominal energies. Taking both of these effects into account, the in-orbit data agree with the on-ground measurements within similar to 5%, without employing the artificial correction introduced in previous work (Kokubun et al. 2007, PASJ, 59, S53). With this knowledge, we updated the data processing, the response, and the auxiliary files of GSO, and reproduced the HXD-PIN and HXD-GSO spectra of the Crab Nebula over 12-300 keV by a broken power-law with a break energy of similar to 110 keV.

      DOI: 10.1093/pasj/63.sp3.S645

      researchmap

    • Spectral and Timing Studies of Cyg X-1 in the Low/Hard State with Suzaku 査読有り

      Shunsuke Torii, Shin'ya Yamada, Kazuo Makishima, Soki Sakurai, Kazuhiro Nakazawa, Hirofumi Noda, Chris Done, Hiromitsu Takahashi, Poshak Gandhi

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN63   S771 - S783   2011年11月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      From 2005 to 2009, 25 observations of Cyg X-1 were performed with Suzaku, achieving a total exposure of 446 ks. In all observations, the source was found in the low/hard state, while the 1.5-12.0 keV count rate of the All-Sky Monitor onboard RXTE varied by a factor of similar to 3. In each observation, the 10-60 keV HXD-PIN spectrum and the 60-400 keV HXD-GSO spectrum were fitted successfully by a thermal Comptonization model plus reflection by a thick neutral material. As the soft X-ray intensity increased, the Compton y-parameter was found to decrease from 1.0 to 0.6, while the solid angle of reflection increased by similar to 30%. Also conducted was a timing analysis over a frequency range of 10(-3)-10 Hz. As the source became brighter in soft X-rays, the characteristic frequency of the hard X-ray variation increased from 0.03 to 0.3 Hz, while the fractional hard X-ray variation integrated over 10(-3)-10(-2) Hz decreased by a factor of similar to 5. The signals in the 60-200 keV band were generally found to vary on shorter time scales than those in the 10-60 keV band. These spectral and timing results can be consistently interpreted by presuming that increases in the mass accretion rate cause the Comptonizing hot corona to shrink, while the optically-thick disk to intrude deeper therein.

      DOI: 10.1093/pasj/63.sp3.S771

      researchmap

    • Suzaku Studies of Wide-Band Spectral Variability of the Bright Type I Seyfert Galaxy Markarian 509 査読有り

      Hirofumi Noda, Kazuo Makishima, Shin'ya Yamada, Shunsuke Torii, Soki Sakurai, Kazuhiro Nakazawa

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN63   S925 - S936   2011年11月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      The Type I Seyfert galaxy Markarian 509 was observed with Suzaku in 2010 November, for a gross time span of 2.2 days. The timing and spectral properties of the 0.5-45 keV X-rays, detected with the XIS and HXD, consistently revealed the presence of a soft spectral component that remained constant while the total X-ray intensity varied by +/- 10%. This stable soft component, found in the 0.5-3.0 keV range, was interpreted as being a result of thermal Comptonization in a corona with a temperature of similar to 0.5 keV and an optical depth of similar to 18. The time-avearged 0.5-45 keV Suzaku spectrum was reproduced successfully, as a combination of this thermal Comptonization component, a harder power-law of photon index similar to 1.8, moderate reflection, and an iron K-emission line. By analyzing four archival Suzaku datasets of the same object obtained in 2006, the thermal Comptonization component, which was stable during 2.2-day pointing in 2010, was found to vary on time scales of a few weeks, independently of the power-law component. Implications of these results are discussed in terms of a "multi-zone Comptonization" view, obtained with Suzaku from the black-hole binary Cygnus X-1.

      DOI: 10.1093/pasj/63.sp3.S925

      researchmap

    • Suzaku Discovery of a Hard Component Varying Independently of the Power-Law Emission in MCG-6-30-15 査読有り

      Hirofumi Noda, Kazuo Makishima, Yuuichi Uehara, Shin'ya Yamada, Kazuhiro Nakazawa

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN63 ( 2 ) 449 - 458   2011年4月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      Focusing on hard X-ray variability, we reanalyzed Suzaku data of the Type I Seyfert galaxy MCG-6-30-15 obtained in 2006. Intensity-sorted spectroscopy and a principal-component analysis consistently revealed a very hard component that varies independently of the dominant power-law emission. Although the exact nature of this hard component has not yet been identified, it can be modeled as a power-law with a photon index of 2 affected by a partial covering absorption, or as a thermal Comptonization emission with a relatively large optical depth. When this component is included in the fitting model, the time-averaged 2.5-55 keV spectrum of MCG-6-30-15 can be reproduced successfully by invoking a mildly broadened iron line with its emission region located at greater than or similar to 8 times the gravitational radii from the central black hole, and a moderate reflection with a covering fraction of similar to 3.4 pi. This result implies that the solution of a highly spinning black hole in MCG-6-30-15, obtained by Miniutti et al. (2007, PASJ, 59, S315) using the same Suzaku data as ours, is a model-dependent result.

      DOI: 10.1093/pasj/63.2.449

      researchmap

    • Long-duration γ ray emissions from 2007 and 2008 winter thunderstorms 査読有り

      H. Tsuchiya, T. Enoto, S. Yamada, T. Yuasa, K. Nakazawa, T. Kitaguchi, M. Kawaharada, M. Kokubun, H. Kato, M. Okano, K. Makishima

      J. Geophys. Res.116 ( 9 )   2011年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Wiley-Blackwell  

      DOI: 10.1029/2010JD015161

      Scopus

      researchmap

    • White dwarf masses in intermediate polars observed with the Suzaku satellite 査読有り

      T. Yuasa, K. Nakazawa, K. Makishima, K. Saitou, M. Ishida, K. Ebisawa, H. Mori, S. Yamada

      ASTRONOMY & ASTROPHYSICS520   A25   2010年9月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:EDP SCIENCES S A  

      Context. White dwarfs (WDs) in cataclysmic variables (CVs) are important experimental laboratories where the electron degeneracy is taking place on a macroscopic scale. Magnetic CVs increase in number especially in the hard X-ray band (greater than or similar to 10 keV) thanks to sensitive hard X-ray missions.
      Aims. From X-ray spectroscopy, we estimate the masses of nearby WDs in moderately-magnetized CVs, or Intermediate Polars (IPs).
      Methods. Using the Suzaku satellite, we aquired wide-band spectra of 17 IPs, covering 3-50 keV. An accretion column model of Suleimanov et al. (2005, A&A, 435, 191) and an optically-thin thermal emission code were used to construct a spectral emission model of IPs with resolved Fe emission lines. By simultaneously fitting the Fe line complex and the hard X-ray continuum of individual spectra, the shock temperature and the WD mass were determined with a better accuracy than in previous studies.
      Results. We determined the WD masses of the 17 IPs with statistical fitting errors of less than or similar to 0.1-0.2 M-circle dot in many cases. The WD mass of a recently-found IP, IGR J17195-4100, was also estimated for the first time (1.03(-0.22)(+0.24) M-circle dot). The average WD mass of the sample is 0.88 +/- 0.25 M-circle dot. When our results were compared with previous X-ray mass determinations, we found significant deviation in a few systems although the reason of this is unclear. The iron abundance of the accreting gas was also estimated, and confirmed the previously reported sub-solar tendency in all sources with better accuracy.

      DOI: 10.1051/0004-6361/201014542

      researchmap

    • THE CONSTANT INNER-DISK RADIUS OF LMC X-3: A BASIS FOR MEASURING BLACK HOLE SPIN 査読有り

      James F. Steiner, Jeffrey E. McClintock, Ronald A. Remillard, Lijun Gou, Shin'ya Yamada, Ramesh Narayan

      ASTROPHYSICAL JOURNAL LETTERS718 ( 2 ) L117 - L121   2010年8月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      The black hole binary system LMC X-3 has been observed by virtually every X-ray mission since the inception of X-ray astronomy. Among the persistent sources, LMC X-3 is uniquely both habitually soft and highly variable. Using a fully relativistic accretion disk model, we analyze hundreds of spectra collected during eight X-ray missions that span 26 years. For a selected sample of 391 RXTE spectra, we find that to within approximate to 2% the inner radius of the accretion disk is constant over time and unaffected by source variability. Even considering an ensemble of eight X-ray missions, we find consistent values of the radius to within approximate to 4%-6%. Our results provide strong evidence for the existence of a fixed inner-disk radius. The only reasonable inference is that this radius is closely associated with the general relativistic innermost stable circular orbit. Our findings establish a firm foundation for the measurement of black hole spin.

      DOI: 10.1088/2041-8205/718/2/L117

      researchmap

    • WIDE-BAND SUZAKU ANALYSIS OF THE PERSISTENT EMISSION FROM SGR 0501+4516 DURING THE 2008 OUTBURST 査読有り

      T. Enoto, N. Rea, Y. E. Nakagawa, K. Makishima, T. Sakamoto, P. Esposito, D. Goetz, K. Hurley, G. L. Israel, M. Kokubun, S. Mereghetti, H. Murakami, K. Nakazawa, L. Stella, A. Tiengo, R. Turolla, S. Yamada, K. Yamaoka, A. Yoshida, S. Zane

      ASTROPHYSICAL JOURNAL715 ( 1 ) 665 - 670   2010年5月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      We observed the soft gamma repeater SGR 0501+4516 with Suzaku for similar to 51 ks on 2008 August 26-27, about 4 days after its discovery. Following the first paper, which reported on the persistent soft X-ray emission and the wide-band spectrum of an intense short burst, this paper presents an analysis of the persistent broadband (1-70 keV) spectra of this source in outburst, taken with the X-ray Imaging Spectrometer (XIS) and the Hard X-ray Detector (HXD). Pulse-phase folding in the 12-35 keV HXD-PIN data on an ephemeris based on multi-satellite timing measurements at soft X-rays revealed the pulsed signals at greater than or similar to 99% confidence in the hard X-ray band. The wide-band spectrum clearly consists of a soft component and a separate hard component, crossing over at similar to 7 keV. When the soft component is modeled by a blackbody plus a Comptonized blackbody, the hard component exhibits a 20-100 keV flux of 4.8(-0.6)(+0.8) (stat.)(-0.4)(+ 0.8) (sys.) x 10(-11) erg s(-1) cm(-2) and a photon index of Gamma = 0.79(-0.18)(+ 0.01) (sys.). The hard X-ray data are compared with those obtained by INTEGRAL about 1 day later. Combining the present results with those on other magnetars, we discuss a possible correlation between the spectral hardness of magnetars and their characteristic age and magnetic field strengths.

      DOI: 10.1088/0004-637X/715/1/665

      researchmap

    • Suzaku X-Ray and Optical Spectroscopic Observations of SS 433 in the 2006 April Multiwavelength Campaign 査読有り

      Kaori Kubota, Yoshihiro Ueda, Nobuyuki Kawai, Taro Kotani, Masaaki Namiki, Kenzo Knugasa, Shinobu Ozaki, Takashi Iijima, Sergei Fabrika, Takayuki Yuasa, Shin'ya Yamada, Kazuo Makishima

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN62 ( 2 ) 323 - 333   2010年4月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      We report on results of the 2006 April multiwavelength campaign of SS 433, focusing on X-ray data observed with Suzaku at two orbital phases (in- and out-of-eclipse phases) and on simultaneous optical spectroscopic observations. Analyzing the Fe XXV K alpha lines originating from the jets, we detected a rapid variability of the Doppler shifts, dz/dt approximate to 0.019/0.33 d(-1), which is larger than those expected from the precession and/or nodding motion. This phenomenon probably corresponds to "jitter" motions observed for the first time in X-rays, for which significant variabilities in both the jet angle and the intrinsic speed are required. From time lags between optical Doppler curves and X-ray ones, we estimated a distance between the optical jets and the base to be similar to (3-4) x 10(14)cm. Based on the radiatively cooling jet model, we determined that the innermost temperatures of the jets are T-0 = 13 +/- 2 keV for the out-of-eclipse phase and 16 3 keV for the in-eclipse (the average of the blue and red jets) from the line intensity ratio of Fe xxv Ka and Fe XXVI K alpha. While the broad-band-continuum spectra over the 5-40 keV band in eclipse is consistent with a multitemperature-bremsstrahlung emission expected from the jets and its reflection component from cold matter, the out-of-eclipse spectrum is harder than the jet emission with the base temperature determined above, implying the presence of an additional hard component.

      DOI: 10.1093/pasj/62.2.323

      researchmap

    • On-orbit calibration status of the Hard X-ray Detector (HXD) onboard Suzaku 査読有り

      S. Nishino, Y. Fukazawa, T. Mizuno, H. Takahashi, K. Hayashi, K. Hiragi, M. Mizuno, S. Yamada, M. Kawaharada, M. Kokubun, K. Nakazawa, S. Watanabe, T. Tanaka, Y. Terada

      Proceedings of SPIE - The International Society for Optical Engineering7732   2010年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

      Hard X-ray Detector (HXD) onboard Suzaku, the Japanese 5th X-ray observatory, consists of 64 PIN photo diodes with 2 mm thickness (10-70 keV) and 16 phoswich detectors using 5 mm-thick GSO scintillators and BGO active collimators (40-600 keV), and these are surrounded by 20 units of BGO Active shields. All the detector units have been working well with no significant troubles in four and a half years since the launch on July 2005, and given many important scientific results. In this paper, we report the recent status of onorbit calibrations for PIN/GSO detectors. For the PIN, analog/digital threshold levels of both in-orbit and on-ground are raised up to avoid the increasing noise events due to in-orbit radiation damage. For the GSO, the accuracy of the energy scale and modeling of gain variations are improved, and newly calibrated data set including background files and response matrices are released on April 2010. © 2010 SPIE.

      DOI: 10.1117/12.856888

      Scopus

      researchmap

      その他リンク: http://orcid.org/0000-0003-3529-3029

    • Suzaku wide-band observations of black-hole binaries and AGNs: continuum and Fe-K lines 査読有り

      Shin'ya Yamada, K. Makishima, K. Nakazawa, H. Noda, H. Takahashi, T. Dotani, A. Kubota, K. Ebisawa, Y. Ueda, C. Done

      X-RAY ASTRONOMY-2009: PRESENT STATUS, MULTI-WAVELENGTH APPROACH AND FUTURE PERSPECTIVES, PROCEEDINGS1248   317 - +   2010年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)   出版者・発行元:AMER INST PHYSICS  

      Suzaku has enabled us to study wide-band spectral and timing properties of black-hole binaries and AGNs more accurately than ever, and revealed how the continuum definition can affect Fe-K line profiles. We have reproduced 0.5-300 keV spectra of Cyg X-1 and GRO J1655-40 in terms of thermal Comptonization in highly inhomogeneous coronae. In both objects, R-in was constrained by the Fe-K line profile and soft excess as similar to 10 R-g, as opposed to the relativistic Fe-K line reported in the literature. We also re-analyzed the 0.7-300 keV Suzaku spectra of OX 339-4, and found that a careful modeling of the continuum leads to R-in > R-g(Yamada et al. 2009), again in disagreement with Miller et al. (2008). Furthermore, through a systematic analysis of AGNs, we discovered a hard spectral component in the HXD-PIN band, which varies independently of the powerlaw. Taking this into account, the time-averaged spectra of MCG-6-30-15 have been explained by invoking neither a large refection fraction, nor an extreme broad Fe-K line. The essence here is that the hard X-ray (20-40 keV) bump may be partially explained as an additional Comptonization component. Our results indicate that the extremely relativistic Fe-K line reported for some objects is not a unique solution, and depends in many cases on the continuum modeling.

      researchmap

    • IS THE BLACK HOLE IN GX 339-4 REALLY SPINNING RAPIDLY? 査読有り

      S. Yamada, K. Makishima, Y. Uehara, K. Nakazawa, H. Takahashi, T. Dotani, Y. Ueda, K. Ebisawa, A. Kubota, P. Gandhi

      ASTROPHYSICAL JOURNAL LETTERS707 ( 2 ) L109 - L113   2009年12月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      The wide-band Suzaku spectra of the black hole (BH) binary GX 339-4, acquired in 2007 February during the Very High state, were reanalyzed. Effects of event pileup (significant within similar to 3' of the image center) and telemetry saturation of the X-ray Imaging Spectrometer (XIS) data were carefully considered. The source was detected up to similar to 300 keV, with an unabsorbed 0.5-200 keV luminosity of 3.8 x 10(38) erg s(-1) at 8 kpc. The spectrum can be approximated by a power law of photon index 2.7, with a mild soft excess and a hard X-ray hump. When using the XIS data outside 2' of the image center, the Fe K line appeared extremely broad, suggesting a high BH spin as already reported by Miller et al. based on the same Suzaku data and other CCD data. When the XIS data accumulation is further limited to > 3' to avoid event pileup, the Fe K profile becomes narrower, and a marginally better solution appears which suggests that the inner disk radius is 5-14 times the gravitational radius (1 sigma), though a maximally spinning BH is still allowed by the data at the 90% confidence level. Consistently, the optically thick accretion disk is inferred to be truncated at a radius 5-32 times the gravitational radius. Thus, the Suzaku data allow an alternative explanation without invoking a rapidly spinning BH. This inference is further supported by the disk radius measured previously in the High/Soft state.

      DOI: 10.1088/0004-637X/707/2/L109

      researchmap

    • Suzaku Observation of the Metallicity in the Interstellar Medium of NGC 4258 査読有り

      Saori Konami, Kosuke Sato, Kyoko Matsushita, Shin'ya Yamada, Naoki Isobe, Atsushi Senda, Asami Hayato, Poshak Gandhi, Toru Tamagawa, Kazuo Makishima

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN61 ( 5 ) 941 - 948   2009年10月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      The Suzaku X-ray satellite observed the nearby spiral galaxy NGC 4258 for a total good exposure time of 100 ks. We present an analysis of the Suzaku XIS data, in which we confirm that the 0.5-2 keV spectra of the interstellar medium (ISM) are well-represented by a two-temperature model. The cool and hot ISM temperatures are 0.23 +/- 0.01 and 0.58 +/- 0.01 keV, respectively. Suzaku's excellent spectral sensitivity has enabled us to measure the metal abundances of O, Ne, Mg, Si, and Fe of the ISM for the first time. The resultant abundance pattern of 0, Mg, Si, and Fe is consistent with that of the new solar abundance table of Lodders (2003, ApJ, 591, 1220), rather than Anders and Grevesse (1989, Geochim. Cosmochim. Acta, 53, 197). This suggests that the metal enrichment processes of NGC 4258 and of our Galaxy are similar.

      DOI: 10.1093/pasj/61.5.941

      researchmap

    • Suzaku Results on the Obscured Low-Luminosity Active Galactic Nucleus in NGC 4258 査読有り

      Shin'ya Yamada, Takeshi Itoh, Kazuo Makishima, Kazuhiro Nakazawa

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN61 ( 2 ) 309 - 319   2009年4月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      In 2006 June, the obscured low-luminosity active galactic nucleus in the nearby Seyfert 1.9 galaxy NGC 4258 was observed with Suzaku for similar to 100 ks. Utilizing the XIS and the HXD, the nucleus emission was detected over a similar to 2 to similar to 40 keV range, with ail unabsorbed 2-10 keV luminosity of similar to 8 x 10(40)) erg s(-1); it varied by a factor of similar to 2 during the observation. Its 2-40 keV spectrum is reproduced by a single power law with a photon index of Gamma similar to 2.0, absorbed by an equivalent hydrogen column of similar to 1.0 x 10(23) cm(2). The spectrum within 4' of the nucleus also required a softer thin-thermal emission, as well as an intermediate hardness component, attributable to integrated point sources. A weak neutral Fe-K alpha florescence line was detected at ail equivalent width of similar to 40eV. A cold reflection component was not required by the data, with the reflector solid angle Omega seen from the nucleus constrained as Omega/2 pi less than or similar to 0.3, assuming a general case of 60 degrees inclination. The results suggest that the cold reflecting material around the nucleus is localized along Our line of sight, rather than forming a thick torus.

      DOI: 10.1093/pasj/61.2.309

      researchmap

    • SUZAKU OBSERVATION OF THE NEW SOFT GAMMA REPEATER SGR 0501+4516 IN OUTBURST 査読有り

      T. Enoto, Y. E. Nakagawa, N. Rea, P. Esposito, D. Goetz, K. Hurley, G. L. Israel, M. Kokubun, K. Makishima, S. Mereghetti, H. Murakami, K. Nakazawa, T. Sakamoto, L. Stella, A. Tiengo, R. Turolla, S. Yamada, K. Yamaoka, A. Yoshida, S. Zane

      ASTROPHYSICAL JOURNAL LETTERS693 ( 2 ) L122 - L126   2009年3月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      We present the first Suzaku observation of the new Soft Gamma Repeater, SGR 0501+4516, performed on 2008 August 26, four days after the onset of bursting activity of this new member of the magnetar family. The soft X-ray persistent emission was detected with the X-ray Imaging Spectrometer (XIS) at a 0.5-10 keV flux of 3.8 x 10-(11) erg s(-1) cm(-2), with a spectrum well fitted by an absorbed blackbody plus power-law model. The source pulsation was confirmed at a period of 5.762072 +/- 0.000002 s, and 32 X-ray bursts were detected by the XIS, four of which were also detected at higher energies by the Hard X-ray Detector (HXD). The strongest burst, which occurred at 03:16:16.9 (UTC), was so bright that it caused instrumental saturation, but its precursor phase, lasting for about 200 ms, was detected successfully over the 0.5-200 keV range, with a fluence of similar to 2.1 x 10(-7) erg cm-2 and a peak intensity of about 89 crab. The entire burst fluence is estimated to be similar to 50 times higher. The precursor spectrum was very hard, and well modeled by a combination of two blackbodies. We discuss the bursting activity and X/gamma-ray properties of this newly discovered Soft Gamma Repeater in comparison with other members of the class.

      DOI: 10.1088/0004-637X/693/2/L122

      researchmap

    • Broad-Band Spectrum of the Black Hole Candidate IGR J17497-2821 Studied with Suzaku 査読有り

      Adamantia Paizis, Ken Ebisawa, Hiromitsu Takahashi, Tadayasu Dotani, Takayoshi Kohmura, Motohide Kokubun, Jerome Rodriguez, Yoshihiro Ueda, Roland Walter, Shin'ya Yamada, Kazutaka Yamaoka, Takayuki Yuasa

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN61   S107 - S113   2009年1月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      The broad-band 1-300 keV Suzaku spectrum of IGR J17497-2821, the X-ray transient discovered by INTEGRAL in 2006 September, is presented. Suzaku observed IGR J17497-2821 on September 25, eight days after its discovery, for a net exposure of about 53 ks. During the Suzaku observation, IGR J17497-2821 is very bright, 2 x 10(37) erg s(-1) at 8 kpc in the 1-300 keV range, and shows a hard spectrum, typical of black hole candidates in the low-hard state. Despite the multi-mission X-ray monitoring of the source, only with Suzaku is it possible to obtain a broad-band spectrum in the 1-300 keV range with a very high signal to noise ratio. A sum of a multi-color disc and a thermal Comptonization component with mild reflection is a good representation of our IGR J17497-2821 Suzaku spectrum. The spectral properties of the accretion disc as well as the cut-off energy in the spectrum at about 150 keV are clearly detected and constrained. We discuss the implications on the physical model used to interpret the data and the comparison with previous results.

      DOI: 10.1093/pasj/61.sp1.S107

      researchmap

    • EMERGENCE OF HYPERONS IN FAILED SUPERNOVAE: TRIGGER OF THE BLACK HOLE FORMATION 査読有り

      K. Sumiyoshi, C. Ishizuka, A. Ohnishi, S. Yamada, H. Suzuki

      ASTROPHYSICAL JOURNAL LETTERS690 ( 1 ) L43 - L46   2009年1月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:IOP PUBLISHING LTD  

      We investigate the emergence of strange baryons in the dynamical collapse of a nonrotating massive star to a black hole using neutrino-radiation hydrodynamical simulations in general relativity. By following the dynamical formation and collapse of a nascent proto-neutron star from the gravitational collapse of a 40 M(circle dot) star adopting a new hyperonic equation-of-state (EOS) table, we show that the hyperons do not appear at the core bounce but populate quickly similar to 0.5-0.7 s after the bounce to trigger the recollapse to a black hole. They start to show up off center owing to high temperatures and later prevail at center when the central density becomes high enough. The neutrino emission from the accreting proto-neutron star with the hyperonic EOS stops much earlier than the corresponding case with a nucleonic EOS, while the average energies and luminosities are quite similar in the two cases. These features of the neutrino signal are a potential probe of the emergence of new degrees of freedom inside the black hole forming collapse.

      DOI: 10.1088/0004-637X/690/1/L43

      researchmap

    • Modeling and Reproducibility of Suzaku HXD PIN/GSO Background 査読有り

      Yasushi Fukazawa, Tsunefumi Mizuno, Shin Watanabe, Motohide Kokubun, Hiromitsu Takahashi, Naomi Kawano, Sho Nishino, Mahito Sasada, Hirohisa Shirai, Takuya Takahashi, Yudai Umeki, Tomonori Yamasaki, Tomonori Yasuda, Aya Bamba, Masanori Ohno, Tadayuki Takahashi, Masayoshi Ushio, Teruaki Enoto, Takao Kitaguchi, Kazuo Makishima, Kazuhiro Nakazawa, Yuichi Uehara, Shin'ya Yamada, Takayuki Yuasa, Naoki Isobe, Madoka Kawaharada, Takaaki Tanaka, Makoto S. Tashiro, Yukikatsu Terada, Kazutaka Yamaoka

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN61   S17 - S33   2009年1月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      Suzaku Hard X-ray Detector (HXD) achieved the lowest background level than any other previously or currently operational missions sensitive in the energy range of 10-600 keV, by utilizing PIN photodiodes and GSO scintillators; mounted in BGO active shields to reject particle background and Compton-scattered events as much as possible. Because it does not have an imaging capability nor rocking mode for the background monitor, the sensitivity is limited by the reproducibility of the non X-ray background (NXB) model. We modeled the HXD NXB, which varies with time as well as other satellites with a low-Earth orbit, by utilizing several parameters, including particle monitor counts and satellite orbital/attitude information, The model background is supplied as an event file in which the background events are generated by random numbers, and can be analyzed in the same way as the real data. The reproducibility of the NXB model depends on the event selection criteria (such as cut-off rigidity and energy band) and the integration time, and the 1 sigma systematic error is estimated to be less than 3% (PIN 15-40 keV) and 1% (GSO 50-100 keV) for more than 10 ks exposure.

      DOI: 10.1093/pasj/61.sp1.S17

      researchmap

    • Suzaku Observations of M 82 X-1: Detection of a Curved Hard X-Ray Spectrum 査読有り

      Ryohei Miyawaki, Kazuo Makishima, Shin'ya Yamada, Poshak Gandhi, Tsunefumi Mizuno, Aya Kubota, Takeshi G. Tsuru, Hironori Matsumoto

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN61   S263 - S278   2009年1月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      A report is presented on Suzaku observations of the ultra-luminous X-ray source X-1 in the starburst galaxy M 82, made three times in 2005 October for an exposure of similar to 30 ks each. The XIS signals from a region of radius 3' around the nucleus defined a 2-10 keV flux of 2.1 x 10(-11) erg s(-1) cm(-2) attributable to point sources. The 3.2-10 keV spectrum was slightly more convex than a power-law with a photon index of 1.7. In all observations, the HXD also detected signals from M 82 up to similar to 20 keV, at a 12-20 keV flux of 4.4 x 10(-12) erg s(-1) cm(-2). The HXD spectrum was steeper than that of the XIS. The XIS and HXD spectra can be jointly reproduced by a cutoff power-law model, or similar curved models. Of the detected wide-band signals, 1/3 to 2/3 are attributable to X-1, while the remainder to other discrete sources in M 82. Regardless of the modeling of these contaminants, the spectrum attributable to X-I is more curved than a power-law, with a bolometric luminosity of (1.5-3) x 10(40) ergs(-1). These results are interpreted as Comptonized emission from a black hole of 100-200 solar masses, radiating roughly at the Eddington luminosity.

      DOI: 10.1093/pasj/61.sp1.S263

      researchmap

    • Is the black hole in GX 339-4 really spinning rapidly? 査読有り

      S. Yamada, K. Makishima, Y. Uehara, K. Nakazawa, H. Takahashi, T. Dotani, Y. Ueda, K. Ebisawa, A. Kubota, P. Gandhi

      Astrophysical Journal707 ( 2 ) L109 - L113   2009年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:Institute of Physics Publishing  

      The wide-band Suzaku spectra of the black hole (BH) binary GX 339-4, acquired in 2007 February during the Very High state, were reanalyzed. Effects of event pileup (significant within ∼3′ of the image center) and telemetry saturation of the X-ray Imaging Spectrometer (XIS) data were carefully considered. The source was detected up to ∼300keV, with an unabsorbed 0.5-200keV luminosity of 3.8 × 1038ergs-1 at 8kpc. The spectrum can be approximated by a power law of photon index 2.7, with a mild soft excess and a hard X-ray hump. When using the XIS data outside 2′ of the image center, the Fe K line appeared extremely broad, suggesting a high BH spin as already reported by Miller etal. based on the same Suzaku data and other CCD data. When the XIS data accumulation is further limited to &gt
      3′ to avoid event pileup, the Fe K profile becomes narrower, and a marginally better solution appears which suggests that the inner disk radius is 5-14 times the gravitational radius (1σ), though a maximally spinning BH is still allowed by the data at the 90% confidence level. Consistently, the optically thick accretion disk is inferred to be truncated at a radius 5-32 times the gravitational radius. Thus, the Suzaku data allow an alternative explanation without invoking a rapidly spinning BH. This inference is further supported by the disk radius measured previously in the High/Soft state. © 2009 The American Astronomical Society.

      DOI: 10.1088/0004-637X/707/2/L109

      Scopus

      researchmap

    • The soft gamma-ray detector for the ASTRO-H mission 査読有り

      T. Tanaka, R. Blandford, K. Doutsu, T. Endo, T. Enoto, Y. Fukazawa, K. Fukami, T. Fukuyama, Y. Hanabata, J. Harayama, K. Hayashi, K. Hiragi, S. Ishikawa, J. Kataoka, J. Katsuta, T. Kitaguchi, M. Kokubun, M. Koseki, T. Kozu, G. Madejski, K. Makishima, M. Matsuoka, T. Miura, T. Mizuno, S. Nakahira, K. Nakajima, K. Nakazawa, S. Nishino, H. Nishioka, H. Noda, H. Odaka, S. Saito, S. Sasaki, R. Sato, S. Sugimoto, H. Tajima, T. Takahashi, M. Tashiro, Y. Terada, S. Torii, Y. Uchiyama, Y. Umeki, S. Watanabe, Y. Yaji, S. Yamada, K. Yamaoka, M. Yoshino, T. Yuasa

      IEEE Nuclear Science Symposium Conference Record   2140 - 2144   2009年

      詳細を見る

      掲載種別:研究論文(国際会議プロシーディングス)  

      The Soft Gamma-ray Detector (SGD) on board ASTRO-H (Japanese next high-energy astrophysics mission) is a Compton telescope with narrow field-of-view, which utilizes Compton kinematics to enhance its background rejection capabilities. It is realized as a hybrid semiconductor detector system which consists of silicon and CdTe (cadmium telluride) detectors. It can detect photons in a wide energy band (50-600 keV) at a background level 10 times better than that of the Suzaku Hard X-ray Detector, and is complimentary to the Hard X-ray Imager on board ASTRO-H with an energy coverage of 5-80 keV. Excellent energy resolution is the key feature of the SGD, allowing it to achieve good background rejection capability taking advantage of good angular resolution. An additional capability of the SGD, its ability to measure gamma-ray polarization, opens up a new window to study properties of gamma-ray emission processes. Here we describe the instrument design of the SGD, its expected performance, and its development status. ©2009 IEEE.

      DOI: 10.1109/NSSMIC.2009.5402092

      Scopus

      researchmap

    • Suzaku Discovery of a Hard Component that Varies Independently of the Power-Law in Several Seyfert Galaxies

      Noda H, Uehara Y, Yamada S, Makishima K, Nakazawa K

      Proceeding of The Energetic Cosmos: from Suzaku to ASTRO-H   318 - 319   2009年

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

      researchmap

    • Suzaku results on Cygnus X-1 in the low/hard state 査読有り

      Kazuo Makishima, Hiromitsu Takahashi, Shin'ya Yamada, Chris Done, Aya Kubota, Tadayasu Dotani, Ken Ebisawa, Takeshi Itoh, Shunji Kitamoto, Hitoshi Negoro, Yoshihiro Ueda, Kazutaka Yamaoka

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN60 ( 3 ) 585 - 604   2008年6月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      The black-hole binary Cygnus X-1 was observed for 17 ks with the Suzaku X-ray observatory in 2005 October, while it was in a low/hard state with a 0.7-300 keV luminosity of 4.6 x 10(37) ergs(-1). The XIS and HXD spectra, spanning 0.7-400 keV, were reproduced successfully, incorporating a cool accretion disk and a hot Comptonizing corona. The corona is characterized by an electron temperature of similar to 100 keV, and two optical depths of similar to 0.4 and similar to 1.5, which account for the softer and harder continua, respectively. The disk has an innermost temperature of similar to 0.2keV, and is thought to protrude half way into the corona. The disk not only provides seed photons to the Compton cloud, but also produces a soft spectral excess, a mild reflection hump, and a weakly broadened iron line. A comparison with the Suzaku data on GRO J1655-40 reveals several interesting spectral differences, which can mostly be attributed to inclination effects, assuming that the disk has a flat geometry while the corona is grossly spherical. An intensity-sorted spectroscopy indicates that the continuum becomes less Comptonized when the source flares up on time scales of 1-200 s, while the underlying disk remains unchanged.

      DOI: 10.1093/pasj/60.3.585

      researchmap

    • Experimental study of the atmospheric neutrino backgrounds for p\textrightarrowe$^+$\ensuremath\pi$^0$ searches in water Cherenkov detectors 査読有り

      Mine S, Alcaraz J, Andringa S, Aoki S, Argyriades J. et, a, Yamada S, th author out, authors

      Physical Review Dvol.77   032003   2008年2月

    • Detection of gamma-rays from winter thunderclouds along the coast of Japan Sea 査読有り

      Enoto T, Tsuchiya H, Yamada S, Yuasa T, Kawaharada M

      International Cosmic Ray Conferencevol.1   745 - 748   2008年1月

      詳細を見る

    • Hard X-ray Imager (HXI) for the NeXT mission 査読有り

      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 Engineering7011   2008年

      詳細を見る

      掲載種別:研究論文(国際会議プロシーディングス)  

      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: 10.1117/12.788290

      Scopus

      researchmap

    • Detection of high-energy gamma rays from winter thunderclouds 査読有り

      H. Tsuchiya, T. Enoto, S. Yamada, T. Yuasa, M. Kawaharada, T. Kitaguchi, M. Kokubun, H. Kato, M. Okano, S. Nakamura, K. Makishima

      PHYSICAL REVIEW LETTERS99 ( 16 ) 165002   2007年10月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:AMER PHYSICAL SOC  

      A report is made on a comprehensive observation of a burstlike gamma-ray emission from thunderclouds on the Sea of Japan, during strong thunderstorms on 6 January 2007. The detected emission, lasting for similar to 40 sec, preceded cloud-to-ground lightning discharges. The burst spectrum, extending to 10 MeV, can be interpreted as consisting of bremsstrahlung photons originating from relativistic electrons. This ground-based observation provides the first clear evidence that strong electric fields in thunderclouds can continuously accelerate electrons beyond 10 MeV prior to lightning discharges.

      DOI: 10.1103/PhysRevLett.99.165002

      researchmap

    • In-orbit performance of the hard X-ray Detector on board Suzaku 査読有り

      Motohide Kokubun, Kazuo Makishima, Tadayuki Takahashi, Toshio Murakami, Makoto Tashiro, Yasushi Fukazawa, Tuneyoshi Kamae, Greg M. Madejski, Kazuhiro Nakazawa, Kazutaka Yamaoka, Yukikatsu Terada, Daisuke Yonetoku, Shin Watanabe, Toru Tamagawa, Tsunefumi Mizuno, Aya Kubota, Naoki Isobe, Isao Takahashi, Goro Sato, Hiromitsu Takahashi, Soojing Hong, Madoka Kawaharada, Naomi Kawano, Takefumi Mitani, Mio Murashima, Masaya Suzuki, Keiichi Abe, Ryouhei Miyawaki, Masanori Ohno, Takaaki Tanaka, Takayuki Yanagida, Takeshi Itoh, Kousuke Ohnuki, Ken-ichi Tamura, Yasuhiko Endo, Shinya Hirakuri, Tatsuro Hiruta, Takao Kitaguchi, Tetsuichi Kishishita, Satoshi Sugita, Takuya Takahashi, Shin'ichiro Takeda, Teruaki Enoto, Ayumi Hirasawa, Jun'ichiro Katsuta, Satoshi Matsumura, Kaori Onda, Mitsuhiro Sato, Masayoshi Ushio, Shin-nosuke Ishikawa, Koichi Murase, Hirokazu Odaka, Masanobu Suzuki, Yuichi Yaji, Shinya Yamada, Tomonori Yamasaki, Takayuki Yuasa

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN59   S53 - S76   2007年1月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      The in-orbit performance and calibration of the Hard X-ray Detector (HXD) on board the X-ray astronomy satellite Suzaku are described. Its basic performances, including a wide energy bandpass of 10-600keV, energy resolutions of similar to 4 keV (FWHM) at 40 keV and similar to 11% at 511 keV, and a high background rejection efficiency, have been confirmed by extensive in-orbit calibrations. The long-term gains of PIN-Si diodes have been stable within 1% for half a year, and those of scintillators have decreased by 5-20%. The residual non-X-ray background of the HXD is the lowest among past non-imaging hard X-ray instruments in energy ranges of 15-70 and 150-500 keV. We provide accurate calibrations of energy responses, angular responses, timing accuracy of the HXD, and relative normalizations to the X-ray CCD cameras using multiple observations of the Crab Nebula.

      DOI: 10.1093/pasj/59.sp1.S53

      researchmap

    • Suzaku discovery of iron absorption lines in outburst spectra of the X-ray transient 4U 1630-472 査読有り

      Aya Kubota, Tadayasu Dotani, Jean Cottam, Taro Kotani, Chris Done, Yoshihiro Ueda, Andrew C. Fabian, Tomonori Yasuda, Hiromitsu Takahashi, Yasushi Fukazawa, Kazutaka Yamaoka, Kazuo Makishima, Shinya Yamada, Takayoshi Kohmura, Lorella Angelini

      PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN59   S185 - S198   2007年1月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(学術雑誌)   出版者・発行元:OXFORD UNIV PRESS  

      We present the results of six Suzaku observations of the recurrent black hole transient 4U 1630-472 during its decline from outburst from February 8 to March 23 in 2006. All observations show the typical high/soft state spectral shape in the 2-50keV band, roughly described by an optically thick-disk spectrum in the soft energy band plus a weak power-law tail that becomes dominant only above similar to 20 keV. The disk temperature decreases from 1.4 keV to 1.2 keV as the flux decreases by a factor of 2, consistent with a constant radius, as expected for disk-dominated spectra. All of the observations reveal significant absorption lines from highly ionized (H-like and He-like) iron K alpha's at 7.0 keV and 6.7 keV. The energies of these absorption lines suggest a blue shift with an outflow velocity of similar to 1000 km s(-1). The H-like iron K alpha equivalent width remains approximately constant at similar to 30 eV over all of the observations, while that of the He-like Ka line increases from 7 eV to 20 eV. Thus, the ionization state of the material decreases, as expected from the decline in flux. By fitting the profile with Voigt functions (curve of growth) together with detailed photo-ionization calculations, the total absorbing column, and the ionization parameter were estimated to be (1.0-0.7) x 10(23) cm(-2) and (6-4) x 10(4), respectively, for a velocity dispersion of 500 km s(-1). This in turn constrains the size of the plasma to be similar to 10(10) cm, assuming a source distance of 10 kpc.

      DOI: 10.1093/pasj/59.sp1.S185

      researchmap

    • Suzaku observation of the black hole transient 4U1630-472: Discovery of absorption lines 査読有り

      Aya Kubota, Tadayasu Dotani, Jean Cottam, Taro Kotani, Chris Done, Yoshihiro Ueda, Andy C. Fabian, Tomonori Yasuda, Hiromitsu Takahashi, Yasushi Fukazawa, Kazutaka Yamaoka, Kazuo Makishima, Shinya Yamada, Takayoshi Kohmura, Lorella Angelini

      Proceedings of the International Astronomical Union2 ( 238 ) 23 - 28   2006年8月

      詳細を見る

      記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)  

      We present the results of six Suzaku observations of the recurrent black hole transient 4U 1630472 during its decline from its most recent outburst in 2006. All observations show the typical high/soft state spectral shape in the 250 keV band, roughly described by an optically thick disk spectrum in the soft energy band plus a weak power-law tail. The disk temperature decreases from 1.4 keV to 1.2 keV as the flux decreases by a factor 2, consistent with a constant radius as expected for disk-dominated spectra. All the observations reveal significant absorption lines from highly ionized (H-like and He-like) iron K at 7.0 keV and 6.7 keV. The energies of these absorption lines suggest a blue shift with an outflow velocity of 1000 km s 1. The Hlike iron K equivalent width remains approximately constant at 30 eV over all the observations, while that of the Helike K line increases from 7 eV to 20 eV. Thus the ionization state of the material decreases, as expected from the decline in flux. The data constrain the velocity dispersion of the absorber to 2002000 km s 1, and the size of the plasma as 10 10 cm assuming a source distance of 10 kpc. © 2007 International Astronomical Union.

      DOI: 10.1017/S1743921307004620

      Scopus

      researchmap

    ▼全件表示

    MISC

    • ダークバリオン探査ミッションSuper DIOSの開発へ向けた検討 II

      佐藤浩介, 大橋隆哉, 石崎欣尚, 江副祐一郎, 山田真也, 山崎典子, 満田和久, 石田学, 前田良知, 田原譲, 三石郁之, 藤本龍一, 鶴剛, 太田直美, 大里健, 中島真也

      日本天文学会年会講演予稿集2018   225   2018年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 狭輝線I型セイファート銀河Swift J2127.4+5654におけるディレイとハード一次成分

      三宅克馬, 野田博文, 山田真也, 清野愛海, 中澤知洋, 牧島一夫

      日本天文学会年会講演予稿集2018   171   2018年2月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • Concept of X-ray Astronomy Recovery Mission

      Makoto Tashiro, Hironori Maejima, Kenichi Toda, Richard Kelley, Lillian Reichenthal, James Lobell, Robert Petre, Matteo Guainazzi, Elisa Costantini, Mark Edison, Ryuichi Fujimoto, Martin Grim, Kiyoshi Hayashida, Jan-Willem den Herder, Yoshitaka Ishisaki, Stephane Paltani, Kyoko Matsushita, Koji Mori, Gary Sneiderman, Yoh Takei, Yukikatsu Terada, Hiroshi Tomida, Hiroki Akamatsu, Lorella Angelini, Yoshitaka Arai, Hisamitsu Awaki, Iurii Babyk, Aya Bamba, Peter Barfknecht, Kim Barnstable, Thomas Bialas, Branimir Blagojevic, Joseph Bonafede, Clifford Brambora, Laura Brenneman, Greg Brown, Kimberly Brown, Laura Burns, Edgar Canavan, Tim Carnahan, Meng Chiao, Brian Comber, Lia Corrales, Cor de Vries, Johannes Dercksen, Maria Diaz-Trigo, Tyrone Dillard, Michael DiPirro, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan Eckart, Teruaki Enoto, Yuichiro Ezoe, Carlo Ferrigno, Yutaka Fujita, Yasushi Fukazawa, Akihiro Furuzawa, Luigi Gallo, Steve Graham, Liyi Gu, Kohichi Hagino, Kenji Hamaguchi, Isamu Hatsukade, Dean Hawes, Takayuki Hayashi, Cailey Hegarty, Natalie Hell, Junko Hiraga, Edmund Hodges-Kluck, Matt Holland, Ann Hornschemeier, Akio Hoshino, Yuto Ichinohe, Ryo Iizuka, Kazunori Ishibashi, Manabu Ishida, Kumi Ishikawa, Kosei Ishimura, Bryan James, Timothy Kallman, Erin Kara, Satoru Katsuda, Steven Kenyon, Caroline Kilbourne, Mark Kimball, Takao Kitaguchi, Shunji Kitamoto, Shogo Kobayashi, Takayoshi Kohmura, Shu Koyama, Aya Kubota, Maurice Leutenegger, Tom Lockard, Mike Loewenstein, Yoshitomo Maeda, Lynette Marbley, Maxim Markevitch, Connor Martz, Hironori Matsumoto, Keiichi Matsuzaki, Dan McCammon, Brian McNamara, Joseph Miko, Eric Miller, Jon Miller, Kenji Minesugi, Ikuyuki Mitsuishi, Tsunefumi Mizuno, Hideyuki Mori, Koji Mukai, Hiroshi Murakami, Richard Mushotzky, Hiroshi Nakajima, Hideto Nakamura, Shinya Nakashima, Kazuhiro Nakazawa, Chikara Natsukari, Kenichiro Nigo, Yusuke Nishioka, Kumiko Nobukawa, Masayoshi Nobukawa, Hirofumi Noda, Hirokazu Odaka, Mina Ogawa, Takaya Ohashi, Masahiro Ohno, Masayuki Ohta, Takashi Okajima, Atsushi Okamoto, Michitaka Onizuka, Naomi Ota, Masanobu Ozaki, Paul Plucinsky, F. Scott Porter, Katja Pottschmidt, Kosuke Sato, Rie Sato, Makoto Sawada, Hiromi Seta, Ken Shelton, Yasuko Shibano, Maki Shida, Megumi Shidatsu, Peter Shirron, Aurora Simionescu, Randall Smith, Kazunori Someya, Yang Soong, Yasuharu Sugawara, Andy Szymkowiak, Hiromitsu Takahashi, Toru Tamagawa, Takayuki Tamura, Takaaki Tanaka, Yuichi Terashima, Yohko Tsuboi, Masahiro Tsujimoto, Hiroshi Tsunemi, Takeshi Tsuru, Hiroyuki Uchida, Hideki Uchiyama, Yoshihiro Ueda, Shinichiro Uno, Thomas Walsh, Shin Watanabe, Brian Williams, Rob Wolfs, Michael Wright, Shinya Yamada, Hiroya Yamaguchi, Kazutaka Yamaoka, Noriko Yamasaki, Shigeo Yamauchi, Makoto Yamauchi, Keiichi Yanagase, Tahir Yaqoob, Susumu Yasuda, Nasa Yoshioka, Jaime Zabala, Irina Zhuravleva

      SPACE TELESCOPES AND INSTRUMENTATION 2018: ULTRAVIOLET TO GAMMA RAY10699   2018年

      詳細を見る

      記述言語:英語   出版者・発行元:SPIE-INT SOC OPTICAL ENGINEERING  

      The ASTRO-H mission was designed and developed through an international collaboration of JAXA, NASA, ESA, and the CSA. It was successfully launched on February 17, 2016, and then named Hitomi. During the in-orbit verification phase, the on-board observational instruments functioned as expected. The intricate coolant and refrigeration systems for soft X-ray spectrometer (SXS, a quantum micro-calorimeter) and soft X-ray imager (SXI, an X-ray CCD) also functioned as expected. However, on March 26, 2016, operations were prematurely terminated by a series of abnormal events and mishaps triggered by the attitude control system. These errors led to a fatal event: the loss of the solar panels on the Hitomi mission. The X-ray Astronomy Recovery Mission (or, XARM) is proposed to regain the key scientific advances anticipated by the international collaboration behind Hitomi. XARM will recover this science in the shortest time possible by focusing on one of the main science goals of Hitomi, "Resolving astrophysical problems by precise high-resolution X-ray spectroscopy".(1) This decision was reached after evaluating the performance of the instruments aboard Hitomi and the mission's initial scientific results, and considering the landscape of planned international X-ray astrophysics missions in 2020's and 2030's.Hitomi opened the door to high-resolution spectroscopy in the X-ray universe. It revealed a number of discrepancies between new observational results and prior theoretical predictions. Yet, the resolution pioneered by Hitomi is also the key to answering these and other fundamental questions. The high spectral resolution realized by XARM will not offer mere refinements; rather, it will enable qualitative leaps in astrophysics and plasma physics. XARM has therefore been given a broad scientific charge: "Revealing material circulation and energy transfer in cosmic plasmas and elucidating evolution of cosmic structures and objects". To fulfill this charge, four categories of science objectives that were defined for Hitomi will also be pursued by XARM; these include (1) Structure formation of the Universe and evolution of clusters of galaxies; (2) Circulation history of baryonic matters in the Universe; (3) Transport and circulation of energy in the Universe; (4) New science with unprecedented high resolution X-ray spectroscopy. In order to achieve these scientific objectives, XARM will carry a 6 x 6 pixelized X-ray micro-calorimeter on the focal plane of an X-ray mirror assembly, and an aligned X-ray CCD camera covering the same energy band and a wider field of view. This paper introduces the science objectives, mission concept, and observing plan of XARM.

      DOI: 10.1117/12.2309455

      Scopus

      researchmap

    • 狭輝線I型セイファート銀河NGC4051における一次放射成分の時間変動

      三宅克馬, 野田博文, 山田真也, 清野愛海, 中澤知洋, 牧島一夫

      日本天文学会年会講演予稿集2017   175   2017年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • SWIFT J2127.4+5654における時間変動を用いたモデル依存しない成分分解

      三宅克馬, 野田博文, 山田真也, 清野愛海, 中澤知洋, 牧島一夫

      日本天文学会年会講演予稿集2017   179   2017年2月28日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • IC4329Aにおける時間変動を用いたモデル依存しない成分分解(3)

      三宅克馬, 野田博文, 山田真也, 清野愛海, 牧島一夫, 中澤知洋

      日本天文学会年会講演予稿集2016   183   2016年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • X線と可視光の同時モニタで迫る巨大ブラックホール降着流の幾何構造

      野田博文, 峰崎岳夫, 小久保充, 諸隈智貴, 土居守, 森谷友由希, 中澤知洋, 渡辺誠, 中尾光, 今井正尭, 河口賢至, 高木勝俊, 川端美穂, 中岡竜也, 川端弘治, 植村誠, 深沢泰司, 吉田道利, 森鼻久美子, 伊藤洋一, 高木悠平, 新井彰, 伊藤亮介, 斉藤嘉彦, 山田真也, 牧島一夫

      日本天文学会年会講演予稿集2016   252   2016年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • ASTRO‐H衛星搭載軟ガンマ線検出器の衛星総合試験における試験結果

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

      日本物理学会講演概要集(CD-ROM)70 ( 2 ) ROMBUNNO.25PSJ-3   2015年9月24日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • GROWTH実験:雷雲起源ガンマ線放射の石川県での2014年度冬季観測結果と検出器小型化に向けた開発状況

      湯浅孝行, 榎戸輝揚, 土屋晴文, 土屋晴文, 米徳大輔, 澤野達哉, 中澤知洋, 牧島一夫, 楳本大悟, 古田禄大, 山田真也

      日本物理学会講演概要集(CD-ROM)70 ( 2 ) ROMBUNNO.25PSK-9   2015年9月24日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • ASTRO‐H衛星搭載軟ガンマ線検出器の現状と解析ソフトウェアについて

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

      日本天文学会年会講演予稿集2015   256   2015年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 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, 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, 高橋忠幸, 高橋弘充, 武田伸一郎, 田代信, 田中孝明, 田中康之, 寺田幸功, 中澤知洋, 中森健之, 林克洋, BLANDFORD Roger, 牧島一夫, MADEJSKI Grzegorz, 水野恒史, 森國城, 谷津陽一, 山岡和貴, 山田真也, 湯浅孝行, 米徳大輔, LAURENT Philippe, LIMOUSIN Olivier, LEBRUN Francois

      日本物理学会講演概要集(CD-ROM)70 ( 1 ) ROMBUNNO.23PDK-3   2015年3月24日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • GROWTH実験 1:2014年末に新規設置した雷雲ガンマ線検出器と初期成果

      楳本大悟, 土屋晴文, 土屋晴文, 湯浅孝行, 中澤知洋, 榎戸輝揚, 榎戸輝揚, 古田禄大, 山田真也, 牧島一夫, 牧島一夫

      日本物理学会講演概要集(CD-ROM)70 ( 1 ) ROMBUNNO.22PDK-10   2015年3月24日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • GROWTH実験 2:2014‐2015冬に観測された雷由来ガンマ線の詳細解析

      古田禄大, 楳本大悟, 土屋晴文, 土屋晴文, 湯浅孝行, 中澤知洋, 榎戸輝揚, 榎戸輝揚, 山田真也, 牧島一夫, 牧島一夫

      日本物理学会講演概要集(CD-ROM)70 ( 1 ) ROMBUNNO.22PDK-11   2015年3月24日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • K中間子原子X線分光に向けた超伝導遷移端マイクロカロリメータのπ<sup>-</sup>ビーム試験

      橋本直, BENNETT D. A, CURCEANU C, DORIESE W. B, FOWLER J. W, GARD J, GUSTAFSSON F. P, 早野龍五, ILIESCU M, 石元茂, 板橋健太, 岩崎雅彦, 岩崎雅彦, 桑原啓介, MARTON J, 野田博文, O’NEIL G. C, 岡田信二, 癒田治彦, REINTSEMA C. D, 佐藤将春, SCHMIDT D. R, SHI H, 鈴木謙, 鈴木隆敏, SWETZ D. S, 竜野秀行, 竜野秀行, UHLIG J, ULLOM J. N, WIDMANN E, 山田真也, ZMESKAL J

      日本物理学会講演概要集(CD-ROM)70 ( 1 ) ROMBUNNO.21ACF-5   2015年3月24日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 荷電粒子ビーム環境における超伝導遷移端マイクロカロリメータX線検出器の性能評価

      竜野秀行, 竜野秀行, BENNETT D.A, CURCEANU C, DORIESE W.B, FOWLER J.W, GARD J, GUSTAFSSON F.P, 橋本直, 早野龍五, ILIESCU M, 石元茂, 板橋健太, 岩崎雅彦, 岩崎雅彦, 桑原啓介, MARTON J, 野田博文, O’NEIL G.C, 岡田信二, 應田治彦, REINTSEMA C.D, 佐藤将春, SCHMIDT D.R, SHI H, 鈴木謙, 鈴木隆敏, SWETZ D.S, UHLIG J, ULLOM J.N, WIDMANN E, 山田真也, ZMESKAL J

      日本物理学会講演概要集(CD-ROM)70 ( 1 ) ROMBUNNO.24ADF-10   2015年3月24日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 超伝導遷移端マイクロカロリメータを用いたK中間子原子X線精密分光実験

      岡田信二, BENNETT D. A, CURCEANU C, DORIESE W.B, FOWLER J.W, GARD J, GUSTAFSSON F.P, 橋本直, 早野龍五, ILIESCU M, 石元茂, 板橋健太, 岩崎雅彦, 岩崎雅彦, 桑原啓介, MARTON J, 野田博文, O’NEIL G.C, 應田治彦, REINTSEMA C.D, 佐藤将春, SCHMIDT D.R, SHI H, 鈴木謙, 鈴木隆敏, SWETZ D.S, 竜野秀行, 竜野秀行, UHLIG J, ULLOM J.N, WIDMANN E, 山田真也, ZMESKAL J

      日本物理学会講演概要集(CD-ROM)70 ( 1 ) ROMBUNNO.24PCD-5   2015年3月24日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • セイファートNGC3516のX線と可視光の間に見られた光度変動の遅延

      野田博文, 峰崎岳夫, 牧島一夫, 中澤知洋, 諸隈智貴, 小久保充, 土居守, 河口賢至, 伊藤亮介, 川端弘治, 深沢泰司, 中尾光, 渡辺誠, 森鼻久美子, 伊藤洋一, 斉藤嘉彦, 山田真也

      日本天文学会年会講演予稿集2015   207   2015年2月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 冬の日本海沿岸に到来する雷雲由来のガンマ線バースト観測

      楳本大悟, 土屋晴文, 湯浅孝行, 中澤知洋, 榎戸輝揚, 古田禄大, 山田真也, 牧島一夫

      日本地球惑星科学連合大会予稿集(Web)2015   ROMBUNNO.MIS29‐15 (WEB ONLY)   2015年

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • GROWTH実験で2012年に検出された北陸冬季雷雲からの対消滅線

      楳本大悟, 土屋晴文, 榎戸輝揚, 湯浅孝行, 山田真也, 中澤知洋, 牧島一夫

      日本物理学会講演概要集69 ( 2 ) 41   2014年8月22日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • セイファートNGC3227が示す巨大ブラックホールへの降着流の状態遷移

      野田博文, 牧島一夫, 山田真也, 中澤知洋, 三宅克馬

      日本天文学会年会講演予稿集2014   219   2014年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 2012年以降の日本海沿岸の冬季雷雲からの粒子線観測

      楳本大悟, 土屋晴文, 榎戸輝揚, 山田真也, 湯浅孝行, 川原田円, 北口貴雄, 中澤知洋, 国分紀秀, 加藤博, 岡野眞治, 玉川徹, 牧島一夫

      日本物理学会講演概要集69 ( 1 ) 135   2014年3月5日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 降着コンパクト天体の熱的コンプトン過程の新しい考察:「すざく」の結果

      牧島一夫, ZHANG Z, 野田博文, 鳥井俊輔, 櫻井壮希, 小林翔悟, 小野光, 中澤知洋, 杉崎睦, 山田真也, 川口俊宏

      日本天文学会年会講演予稿集2014   85   2014年2月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 2012年中における日本海沿岸の冬季落雷からのガンマ線観測

      楳本大悟, 土屋晴文, 榎戸輝揚, 山田真也, 湯浅孝行, 川原田円, 北口貴雄, 中澤知洋, 国分紀秀, 岩田憲一, 岩田憲一, 加藤博, 岡野眞治, 玉川徹, 牧島一夫

      日本物理学会講演概要集68 ( 2 ) 112   2013年8月26日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • ASTRO‐H衛星搭載軟ガンマ線検出器の衛星搭載品開発

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

      日本物理学会講演概要集68 ( 2 ) 110   2013年8月26日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 活動銀河核のセントラルエンジンの理解に向けて

      牧島一夫, 野田博文, 中澤知洋, 三宅克馬, 山田真也

      日本天文学会年会講演予稿集2013   216   2013年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • Astro‐H衛星搭載軟ガンマ線検出器の開発(2012年度後半)

      水野恒史, 田島宏康, 深沢泰司, 渡辺伸, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 川原田円, 国分紀秀, 佐藤悟朗, 佐藤理江, 高橋忠幸, 高橋弘充, 武田伸一郎, 田代信, 田中孝明, 寺田幸功, 中澤知洋, 中森健之, BLANDFORD Roger, 牧島一夫, MADEJSKI Grzegorz, 森國城, 谷津陽一, 山田真也, 湯浅孝行, 米徳大輔, LAURENT Philippe, LIMOUSIN Olivier, LEBRUN Francois

      日本物理学会講演概要集68 ( 1 ) 134   2013年3月5日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 「すざく」によるセイファート銀河NGC4151の明暗状態の比較

      表尚平, 中澤知洋, 野田博文, 牧島一夫, 平木一至, 深沢泰司, 高橋弘充, 大野雅功, 吉川瑛文, 山田真也, 玉川徹

      日本天文学会年会講演予稿集2013   202   2013年2月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 時間変動から分解する巨大ブラックホール近傍からの複数の一次X線放射

      野田博文, 牧島一夫, 山田真也, 中澤知洋

      日本天文学会年会講演予稿集2013   75   2013年2月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • Astro‐H衛星搭載軟ガンマ線検出器の開発

      深沢泰司, 田島宏康, 渡辺伸, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 川原田円, 国分紀秀, 佐藤悟朗, 佐藤理江, 高橋忠幸, 高橋弘充, 武田伸一郎, 田代信, 田中孝明, 寺田幸功, 中澤知洋, 中森健之, 牧島一夫, 水野恒史, 森國城, 谷津陽一, 山田真也, 湯浅孝行, 米徳大輔, BLANDFORD Roger, MADEJSKI Grzegorz, LAURENT Philippe, LIMOUSIN Olivier, LEBRUN Francois

      日本物理学会講演概要集67 ( 2 ) 119   2012年8月24日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • X線時間変動のみから抽出するAGN反射スペクトル:「すざく」の結果

      野田博文, 牧島一夫, 山田真也, 中澤知洋

      日本天文学会年会講演予稿集2012   214   2012年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 「すざく」で観るCyg X‐1のソフト状態におけるスペクトルの時間変動

      鳥井俊輔, 牧島一夫, 中澤知洋, 野田博文, 桜井壮希, 山田真也

      日本天文学会年会講演予稿集2012   78   2012年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 「すざく」による明るいセイファート銀河NGC4151の鉄吸収線の研究

      表尚平, 牧島一夫, 中澤知洋, 野田博文, 平木一至, 深沢泰司, 高橋弘充, 大野雅功, 吉川瑛文, 山田真也, 玉川徹

      日本天文学会年会講演予稿集2012   214   2012年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 2009年および2010年における雷や雷雲からの放射線観測

      岩田憲一, 土屋晴文, 榎戸輝揚, 山田真也, 湯浅孝行, 川原田円, 北口貴雄, 中澤知洋, 国分紀秀, 加藤博, 岡野眞治, 牧島一夫

      日本物理学会講演概要集67 ( 1 ) 125   2012年3月5日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • Astro‐H衛星搭載軟ガンマ線検出器の開発

      田島宏康, 深沢泰司, 渡辺伸, 内山秀樹, 内山泰伸, 榎戸輝揚, 太田方之, 大野雅功, 小高裕和, 片岡淳, 川原田円, 国分紀秀, 佐藤悟朗, 高橋忠幸, 高橋弘充, 武田伸一郎, 田代信, 田中孝明, 寺田幸功, 中澤知洋, 中森健之, BLANDFORD Roger, 牧島一夫, MADEJSKI Grzegorz, 水野恒史, 森國城, 谷津陽一, 山岡和貴, 山田真也, 湯浅孝行, 米徳大輔, LAURENT Philippe, LIMOUSIN Olivier, LEBRUN Francois

      日本物理学会講演概要集67 ( 1 ) 139   2012年3月5日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • ASTRO‐H:衛星搭載軟ガンマ線検出器(SGD)の開発現状

      渡辺伸, 田島宏康, 深沢泰司, 太田方之, 小高裕和, 川原田円, 国分紀秀, 佐藤悟朗, 高橋忠幸, 武田伸一郎, 森國城, 湯浅孝行, 水野恒史, 高橋弘充, 大野雅功, 内山泰伸, 榎戸輝揚, 田中孝明, BLANDFORD Roger, MADEJSKI Grzegarz, 内山秀樹, 中澤知洋, 牧島一夫, 片岡淳, 中森健之, 谷津陽一, 田代信, 寺田幸功, 山岡和貴, 山田真也, 米徳大輔, LAURENT Philippe, LIMOUSIN Olivier, LEBRUN Francois

      日本天文学会年会講演予稿集2012   282   2012年2月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • X線天文衛星ASTRO‐Hで確立するAGNセントラルエンジンの新描像

      野田博文, 牧島一夫, 中澤知洋, 山田真也

      日本天文学会年会講演予稿集2012   95   2012年2月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 「すざく」で迫るI型セイファート銀河Markarian 509の軟X線超過の起源

      野田博文, 牧島一夫, 山田真也, 中澤知洋

      日本天文学会年会講演予稿集2011   221   2011年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 「すざく」を用いたハード/ソフト状態におけるCyg X‐1の系統解析

      鳥井俊輔, 牧島一夫, 山田真也, 桜井壮希, 中澤知洋, 野田博文

      日本天文学会年会講演予稿集2011   73   2011年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 次期X線衛星ASTRO‐Hへ向けたBGO結晶シンチレータのAPD読み出しによる光収集効率の研究

      西岡博之, 笹野理, 湯浅孝行, 山田真也, 中澤知洋, 牧島一夫, 深沢泰司, 齋藤龍彦, 吉野将生, 中森健之, 片岡淳, 谷津陽一

      日本物理学会講演概要集66 ( 1 ) 123   2011年3月3日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 「すざく」で迫るLow/Hard StateにおけるCyg X‐1の降着流の幾何

      鳥井俊輔, 山田真也, 牧島一夫, 中澤知洋

      日本天文学会年会講演予稿集2010   52   2010年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • ASTRO‐H衛星搭載硬X線イメージャープロトタイプの性能評価

      萩野浩一, 渡辺伸, 川原田円, 石川真之介, 福山太郎, 齋藤新也, 国分紀秀, 高橋忠幸, 中澤知洋, 山田真也, 湯浅孝行, 鳥井俊輔, 中島健太, 西岡博之, 野田博文, 牧島一夫, 田島宏康, 田中孝明, 深沢泰司, 林克洋

      日本物理学会講演概要集65 ( 2 ) 82   2010年8月18日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • ASTRO‐H衛星搭載硬X線・ガンマ線検出器の宇宙線重粒子に対する応答

      国分紀秀, 渡辺伸, 太田方之, 佐藤悟郎, 岸下徹一, 勝田隼一郎, 小高裕和, 石川真之介, 古関優, 佐々木智香子, 斎藤新也, 福山太郎, 中澤知洋, 奥村暁, 山田真也, 鳥井俊輔, 中島健太, 片岡淳, 吉野将生, 三浦大陽, 寺田幸功, 原山淳, 中嶋大, 出原寿紘, 内堀幸夫, 北村尚

      NIRS-M (Natl Inst Radiol Sci) ( 234 ) 270 - 271   2010年6月

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 「すざく」によるセイファート銀河の広がった鉄輝線の新解釈

      野田博文, 牧島一夫, 山田真也, 上原悠一, 中澤知洋

      日本物理学会講演概要集65 ( 1 ) 101   2010年3月1日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 「すざく」を用いたMCG‐6‐30‐15の硬X線放射の新解釈

      野田博文, 山田真也, 上原悠一, 中澤知洋, 牧島一夫

      日本天文学会年会講演予稿集2009   69   2009年8月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 雷や雷雲に付随する高エネルギー放射線バーストの測定

      土屋晴文, 榎戸輝揚, 鳥居建男, 中澤知洋, 山田真也, 湯浅孝行, 鳥井俊輔, 福山太郎, 山口貴弘, 国分紀秀, 加藤博, 岡野眞治, 牧島一夫

      アイソトープ・放射線研究発表会要旨集46th   113   2009年6月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 「すざく」による軟ガンマ線リピーターSGR0501+4516のToO観測(1)

      榎戸輝揚, 中川友進, 牧島一夫, 山岡和貴, 山田真也, 中澤知洋, 村上弘志, 国分紀秀, 坂本貴紀, 吉田篤正

      日本天文学会年会講演予稿集2009   64   2009年2月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 「すざく」による軟ガンマ線リピーターSGR0501+4516のToO観測(2)

      中川友進, 榎戸輝揚, 山田真也, 中澤知洋, 牧島一夫, 山岡和貴, 吉田篤正, 村上弘志, 坂本貴紀, 国分紀秀, HURLEY Kevin, REA Nanda

      日本天文学会年会講演予稿集2009   63   2009年2月20日

      詳細を見る

      記述言語:日本語  

      J-GLOBAL

      researchmap

    • 22pSH-6 「すざく」衛星によるLow-Hard状態におけるCygX-1の観測(II)(22pSH X線・γ線,宇宙線・宇宙物理領域)

      牧島 一夫, 山岡 和貴, 山田 真也, 高橋 弘充, 久保田 あや, 堂谷 忠靖, 海老沢 研, 北本 俊二, 根来 均, 上田 佳宏

      日本物理学会講演概要集63 ( 0 )   2008年

      詳細を見る

      記述言語:日本語   出版者・発行元:一般社団法人 日本物理学会  

      CiNii Article

      researchmap

    • Suzaku discovery of absorption lines from the black hole transient 4U1630-472

      Aya Kubota, Tadayasu Dotani, Jean Cottam, Taro Kotani, Chris Done, Yoshihiro Ueda, Andy C. Fabian, Tomonori Yasuda, Hiromitsu Takahashi, Yasushi Fukazawa, Kazutaka Yamaoka, Kazuo Makishima, Shinya Yamada, Takayoshi Kohmura, Lorella Angelini

      PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT ( 169 ) 225 - 228   2007年

      詳細を見る

      記述言語:英語   出版者・発行元:PROGRESS THEORETICAL PHYSICS PUBLICATION OFFICE  

      We present the results of six Suzaku observations of the recurrent black hole transient 4U 1630-472 during its decline from its most recent outburst in 2006. All observations show the typical high/soft state spectral shape in the 2-50 keV band, roughly described by an optically thick disk spectrum in the soft energy band plus a weak power-law tail. The disk temperature decreases from 1.4 keV to 1.2 keV as the flux decreases by a factor 2, consistent with a constant radius as expected for disk-dominated spectra. All the observations reveal significant absorption lines from highly ionized (H-like and He-like) iron K alpha at 7.0 keV and 6.7 keV. The energies of these absorption lines suggest a blue shift with an outflow velocity of similar to 1000 km s(-1). The H-like iron K alpha equivalent width remains approximately constant at similar to 30 eV over all the observations, while that of the He-like K alpha line increases from 7 eV to 20 eV. Thus the ionization state of the material decreases, as expected from the decline in flux. The data constrain the velocity dispersion of the absorber to 200-2000 km s(-1) and the size of the plasma as similar to 10(10) cm assuming a source distance of 10 kpc.

      CiNii Article

      researchmap

    • 22aZJ-5 「すざく」衛星によるLow-Hard状態におけるCygX-1の観測(22aZJ X線・γ線,宇宙線・宇宙物理領域)

      山田 真也, 山岡 和貴, 根来 均, 「すざく」Cyg X, チーム, 牧島 一夫, 伊藤 健, 中澤 知洋, 久保田 あや, 高橋 弘充, 堂谷 忠靖, 海老沢 研, 北本 俊二

      日本物理学会講演概要集62 ( 0 )   2007年

      詳細を見る

      記述言語:日本語   出版者・発行元:一般社団法人 日本物理学会  

      CiNii Article

      researchmap

    ▼全件表示

    書籍等出版物

    • 「すざく」が見たブラックホール連星 – 激しい強度変動と広帯域スペクトル --」

      山田真也( 担当: 単著)

      日本天文学会  2015年10月 

      詳細を見る

    • 広帯域X線観測で挑むBHの謎 -- 冷たい円盤と非一様なコロナの共存 --

      山田真也( 担当: 単著 ,  範囲: 執筆)

      日本天文学会  2014年7月 

      詳細を見る

    • 恒星質量ブラックホールの回転を計る

      牧島一夫, 山田真也( 担当: 共著)

      日本天文学会  2010年3月 

      詳細を見る

    講演・口頭発表等

    • ブラックホール連星の状態遷移と時間変動 招待有り

      山田真也

      磁気流体プラズマで探る高エネルギー天体現象研究会  2018年8月28日 

      詳細を見る

      記述言語:日本語   会議種別:口頭発表(招待・特別)  

      researchmap

    • 精密X線分光技術の将来展望とそのサイエンス 招待有り

      山田真也

      高エネルギー天文学・宇宙物理学の観測と理論  2018年3月1日 

      詳細を見る

      記述言語:日本語   会議種別:口頭発表(招待・特別)  

      researchmap

    • A future X-ray mission to survey missing baryons 招待有り 国際会議

      山田真也

      New development in astrophysics through multimessenger observations of gravitational wave sources  2016年12月26日 

      詳細を見る

      記述言語:英語   会議種別:口頭発表(招待・特別)  

      researchmap

    • Developing fast-repointing framework for future satellites: based on the X-ray dark-baryon survey mission 招待有り 国際会議

      山田真也

      New development in astrophysics through multimessenger observations of gravitational wave sources  2016年2月18日 

      詳細を見る

      記述言語:英語   会議種別:口頭発表(招待・特別)  

      researchmap

    • Soft X-ray Spectrometer onboard ASTRO-H and future prospects 招待有り

      山田真也

      第13回 X線結像光学シンポジウム  2015年11月17日 

      詳細を見る

      記述言語:日本語   会議種別:口頭発表(招待・特別)  

      researchmap

    • Using SXS and Some hints 招待有り 国際会議

      山田真也

      ASTRO-H 14th science meeting  2015年7月26日 

      詳細を見る

      記述言語:英語   会議種別:口頭発表(招待・特別)  

      researchmap

    • ASTRO-Hが拓くサイエンス「ASTRO-Hの目指すサイエンス (1) ブラックホール」 招待有り

      山田真也

      日本天文学会ASTRO-H特別セッション  2015年3月18日 

      詳細を見る

      記述言語:日本語   会議種別:口頭発表(招待・特別)  

      researchmap

    • Disk-coronal coexistence around black holes revealed with Suzaku 招待有り 国際会議

      山田真也

      Suzaku MAXI 2014  2014年2月12日 

      詳細を見る

      記述言語:英語   会議種別:口頭発表(招待・特別)  

      researchmap

    • Suzaku Wide-band and Temporal Analysis of Cygnus X-1: inhomogeneous coronae and cool disk 招待有り 国際会議

      山田真也

      Prague Synergy 2013  2013年11月25日 

      詳細を見る

      記述言語:英語   会議種別:口頭発表(招待・特別)  

      researchmap

    • ブラックホール連星のX線観測の現状とALMAへの期待 招待有り

      山田真也

      ALMAワークショップ 「ALMAで探るブラックホール高エネルギー現象」  2013年9月25日 

      詳細を見る

      記述言語:日本語   会議種別:口頭発表(招待・特別)  

      researchmap

    • コンパクト天体のコンプトンコロナ 招待有り

      山田真也

      コンパクト星連星の多様性と進化  2013年3月13日 

      詳細を見る

      記述言語:日本語   会議種別:口頭発表(招待・特別)  

      researchmap

    • ブラックホールの不思議 〜我々はどこからきたのか〜 招待有り

      山田真也

      宇宙の化学進化研究会  2012年10月26日 

      詳細を見る

      記述言語:日本語   会議種別:口頭発表(招待・特別)  

      researchmap

    • Wide-band and Intensity-related spectral analysis of Cygnus X-1 with Suzaku 招待有り 国際会議

      山田真也

      Exploring the X-ray Universe: Suzaku and Beyound  2011年6月11日 

      詳細を見る

      記述言語:英語   会議種別:口頭発表(招待・特別)  

      researchmap

    • X線観測によるブラックホール降着流の理解と進展 招待有り

      山田真也

      コンパクト天体で探る極限物理  2011年2月17日 

      詳細を見る

      記述言語:日本語   会議種別:口頭発表(招待・特別)  

      researchmap

    ▼全件表示

    共同研究・競争的資金等の研究

    • X線精密分光によるブラックホールバリオンジェットの観測的研究

      日本学術振興会  科学研究費助成事業 

      山田真也

      詳細を見る

      2015年4月 - 2019年3月

      担当区分:研究代表者  資金種別:競争的資金

      researchmap

    • 重力波天体の即時精密X線分光観測に向けた基盤構築

      日本学術振興会  科学研究費助成事業 

      山田真也

      詳細を見る

      2015年4月 - 2017年3月

      担当区分:研究代表者  資金種別:競争的資金

      researchmap

    • X線分光偏光観測で探るブラックホールの激しい時間変動

      日本学術振興会  科学研究費助成事業 

      山田真也

      詳細を見る

      2012年4月 - 2014年3月

      担当区分:研究代表者  資金種別:競争的資金

      researchmap

    お問い合わせ先
    外部の方
    学内の方