Associate for Education and Public Outreach

海老沢 研

Ken Ebisawa

基本情報

所属
国立研究開発法人宇宙航空研究開発機構 宇宙科学研究所 宇宙物理学研究系 教授

J-GLOBAL ID
201801002962836691
researchmap会員ID
B000323419

外部リンク

主にX線天文学の研究をやっています。X線天体のフォローアップとして、地上赤外線観測、電波観測もやってます。ブラックホール、中性子星、白色矮星、AGN、銀河面からのX線放射などに興味を持っています。

宇宙航空研究開発機構(JAXA)・宇宙科学研究所(ISAS)にて、MAXI、XRISMを始めとする天文衛星のデータ処理・解析システムの開発、宇宙科学データアーカイブDARTSの運用を行っています。DARTSにおける全天多波長早見システムJUDO2を開発しました。また、「あかり」のアーカイブデータを用いて銀河系内の赤外線前景放射を見積もり、将来のLiteBIRDによる宇宙論観測に生かせるようにしたいと考えています。

東京大学大学院理学系研究科天文学専攻の教員です。

 
 

学歴

 2

論文

 252
  • Marc Audard, Hisamitsu Awaki, Ralf Ballhausen, Aya Bamba, Ehud Behar, Rozenn Boissay-Malaquin, Laura Brenneman, Gregory V Brown, Lia Corrales, Elisa Costantini, Renata Cumbee, Maria Diaz-Trigo, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan Eckart, Dominique Eckert, Teruaki Enoto, Satoshi Eguchi, Yuichiro Ezoe, Adam Foster, Ryuichi Fujimoto, Yutaka Fujita, Yasushi Fukazawa, Kotaro Fukushima, Akihiro Furuzawa, Luigi Gallo, Javier A García, Liyi Gu, Matteo Guainazzi, Kouichi Hagino, Kenji Hamaguchi, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Natalie Hell, Edmund Hodges-Kluck, Ann Hornschemeier, Yuto Ichinohe, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Jelle Kaastra, Timothy Kallman, Erin Kara, Satoru Katsuda, Yoshiaki Kanemaru, Richard Kelley, Caroline Kilbourne, Shunji Kitamoto, Shogo Kobayashi, Takayoshi Kohmura, Aya Kubota, Maurice Leutenegger, Michael Loewenstein, Yoshitomo Maeda, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian McNamara, François Mernier, Eric D Miller, Jon M Miller, Ikuyuki Mitsuishi, Misaki Mizumoto, Tsunefumi Mizuno, Koji Mori, Koji Mukai, Hiroshi Murakami, Richard Mushotzky, Hiroshi Nakajima, Kazuhiro Nakazawa, Jan-Uwe Ness, Kumiko Nobukawa, Masayoshi Nobukawa, Hirofumi Noda, Hirokazu Odaka, Shoji Ogawa, Anna Ogorzalek, Takashi Okajima, Naomi Ota, Stephane Paltani, Robert Petre, Paul Plucinsky, Frederick Scott Porter, Katja Pottschmidt, Kosuke Sato, Toshiki Sato, Makoto Sawada, Hiromi Seta, Megumi Shidatsu, Aurora Simionescu, Randall Smith, Hiromasa Suzuki, Andrew Szymkowiak, Hiromitsu Takahashi, Mai Takeo, Toru Tamagawa, Keisuke Tamura, Takaaki Tanaka, Atsushi Tanimoto, Makoto Tashiro, Yukikatsu Terada, Yuichi Terashima, Yohko Tsuboi, Masahiro Tsujimoto, Hiroshi Tsunemi, Takeshi G Tsuru, Hiroyuki Uchida, Nagomi Uchida, Yuusuke Uchida, Hideki Uchiyama, Yoshihiro Ueda, Shinichiro Uno, Jacco Vink, Shin Watanabe, Brian J Williams, Satoshi Yamada, Shinya Yamada, Hiroya Yamaguchi, Kazutaka Yamaoka, Noriko Yamasaki, Makoto Yamauchi, Shigeo Yamauchi, Tahir Yaqoob, Tomokage Yoneyama, Tessei Yoshida, Mihoko Yukita, Irina Zhuravleva, Manan Agarwal, Yuken Ohshiro
    Publications of the Astronomical Society of Japan 2024年10月10日  
    Abstract We present an initial analysis of the X-Ray Imaging and Spectroscopy Mission (XRISM) first-light observation of the supernova remnant (SNR) N 132D in the Large Magellanic Cloud. The Resolve microcalorimeter has obtained the first high-resolution spectrum in the 1.6–10 keV band, which contains K-shell emission lines of Si, S, Ar, Ca, and Fe. We find that the Si and S lines are relatively narrow, with a broadening represented by a Gaussian-like velocity dispersion of $\sigma _v \sim 450$ km s$^{-1}$. However, the Fe He$\alpha$ lines are substantially broadened with $\sigma _v \sim 1670$ km s$^{-1}$. This broadening can be explained by a combination of the thermal Doppler effect due to the high ion temperature and the kinematic Doppler effect due to the SNR expansion. Assuming that the Fe He$\alpha$ emission originates predominantly from the supernova ejecta, we estimate the reverse shock velocity at the time when the bulk of the Fe ejecta were shock heated to be $-1000 \lesssim V_{\rm rs}$ (km s$^{-1}$) $\lesssim 3300$ (in the observer frame). We also find that Fe Ly$\alpha$ emission is redshifted with a bulk velocity of $\sim 890$ km s$^{-1}$, substantially larger than the radial velocity of the local interstellar medium surrounding N 132D. These results demonstrate that high-resolution X-ray spectroscopy is capable of providing constraints on the evolutionary stage, geometry, and velocity distribution of SNRs.
  • Marc Audard, Hisamitsu Awaki, Ralf Ballhausen, Aya Bamba, Ehud Behar, Rozenn Boissay-Malaquin, Laura Brenneman, Gregory V. Brown, Lia Corrales, Elisa Costantini, Renata Cumbee, Maria Diaz Trigo, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E. Eckart, Dominique Eckert, Teruaki Enoto, Satoshi Eguchi, Yuichiro Ezoe, Adam Foster, Ryuichi Fujimoto, Yutaka Fujita, Yasushi Fukazawa, Kotaro Fukushima, Akihiro Furuzawa, Luigi Gallo, Javier A. García, Liyi Gu, Matteo Guainazzi, Kouichi Hagino, Kenji Hamaguchi, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Natalie Hell, Edmund Hodges-Kluck, Ann Hornschemeier, Yuto Ichinohe, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Jelle Kaastra, Timothy Kallman, Erin Kara, Satoru Katsuda, Yoshiaki Kanemaru, Richard Kelley, Caroline Kilbourne, Shunji Kitamoto, Shogo Kobayashi, Takayoshi Kohmura, Aya Kubota, Maurice Leutenegger, Michael Loewenstein, Yoshitomo Maeda, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian McNamara, François Mernier, Eric D. Miller, Jon M. Miller, Ikuyuki Mitsuishi, Misaki Mizumoto, Tsunefumi Mizuno, Koji Mori, Koji Mukai, Hiroshi Murakami, Richard Mushotzky, Hiroshi Nakajima, Kazuhiro Nakazawa, Jan-Uwe Ness, Kumiko Nobukawa, Masayoshi Nobukawa, Hirofumi Noda, Hirokazu Odaka, Shoji Ogawa, Anna Ogorzalek, Takashi Okajima, Naomi Ota, Stephane Paltani, Robert Petre, Paul Plucinsky, Frederick S. Porter, Katja Pottschmidt, Kosuke Sato, Toshiki Sato, Makoto Sawada, Hiromi Seta, Megumi Shidatsu, Aurora Simionescu, Randall Smith, Hiromasa Suzuki, Andrew Szymkowiak, Hiromitsu Takahashi, Mai Takeo, Toru Tamagawa, Keisuke Tamura, Takaaki Tanaka, Atsushi Tanimoto, Makoto Tashiro, Yukikatsu Terada, Yuichi Terashima, Yohko Tsuboi, Masahiro Tsujimoto, Hiroshi Tsunemi, Takeshi Tsuru, Hiroyuki Uchida, Nagomi Uchida, Yuusuke Uchida, Hideki Uchiyama, Yoshihiro Ueda, Shinichiro Uno, Jacco Vink, Shin Watanabe, Brian J. Williams, Satoshi Yamada, Shinya Yamada, Hiroya Yamaguchi, Kazutaka Yamaoka, Noriko Yamasaki, Makoto Yamauchi, Shigeo Yamauchi, Tahir Yaqoob, Tomokage Yoneyama, Tessei Yoshida, Mihoko Yukita, Irina Zhuravleva, Xin Xiang, Takeo Minezaki, Margaret Buhariwalla, Dimitra Gerolymatou, Scott Hagen
    The Astrophysical Journal Letters 973(1) L25-L25 2024年9月1日  
    Abstract We present an analysis of the first two XRISM/Resolve spectra of the well-known Seyfert-1.5 active galactic nucleus (AGN) in NGC 4151, obtained in 2023 December. Our work focuses on the nature of the narrow Fe K α emission line at 6.4 keV, the strongest and most common X-ray line observed in AGN. The total line is found to consist of three components. Even the narrowest component of the line is resolved with evident Fe K α,1 (6.404 keV) and K α,2 (6.391 keV) contributions in a 2:1 flux ratio, fully consistent with neutral gas with negligible bulk velocity. Subject to the limitations of our models, the narrowest and intermediate-width components are consistent with emission from optically thin gas, suggesting that they arise in a disk atmosphere and/or wind. Modeling the three line components in terms of Keplerian broadening, they are readily associated with (1) the inner wall of the “torus,” (2) the innermost optical “broad-line region” (or “X-ray BLR”), and (3) a region with a radius of r ≃ 100 GM/c 2 that may signal a warp in the accretion disk. Viable alternative explanations of the broadest component include a fast-wind component and/or scattering; however, we find evidence of variability in the narrow Fe K α line complex on timescales consistent with small radii. The best-fit models are statistically superior to simple Voigt functions, but when fit with Voigt profiles the time-averaged lines are consistent with a projected velocity broadening of FWHM . Overall, the resolution and sensitivity of XRISM show that the narrow Fe K line in AGN is an effective probe of all key parts of the accretion flow, as it is currently understood. We discuss the implications of these findings for our understanding of AGN accretion, future studies with XRISM, and X-ray-based black hole mass measurements.
  • Katsuhiro Hayashi, Makoto S. Tashiro, Yukikatsu Terada, Tessei Yoshida, Shoji Ogawa, Yoshiaki Kanemaru, Kotaro Fukushima, Akio Hoshino, Hiromitsu Takahashi, Masayoshi Nobukawa, Tsunefumi Mizuno, Kazuhiro Nakazawa, Shin'ichiro Uno, Ken Ebisawa, Satoshi Eguchi, Satoru Katsuda, Takao Kitaguchi, Aya Kubota, Naomi Ota, Megumi Shidatsu, Atsushi Tanimoto, Yuichi Terashima, Yohko Tsuboi, Yuusuke Uchida, Hideki Uchiyama, Shigeo Yamauchi, Tomokage Yoneyama, Satoshi Yamada, Nagomi Uchida, Seiko Sakurai, Shin Watanabe, Ryo Iizuka, Rie Sato, Chris Baluta, Takayuki Tamura, Yasushi Fukazawa, Hirokazu Odaka, Tsubasa Tamba, Ryohei Sato, Sou Kato, Minami Sakama, Takumi Shioiri, Yuki Niida, Natsuki Sakamoto, Noboru Nemoto, Yuki Omiya, Nari Suzuki, Toshihiro Takagi, Yugo Motogami, Matt Holland, Michael Loewenstein, Eric D. Miller, Tahir Yaqoob, Robert S. Hill, Trisha F. Doyle, Efrain Perez-Solis, Morgan D. Waddy, Mark Mekosh, Joseph B. Fox, Matteo Guainazzi, Jan-Uwe Ness, Hironori Maejima, Kenichi Toda, Chikara Natsukari
    Space Telescopes and Instrumentation 2024: Ultraviolet to Gamma Ray 60-60 2024年8月21日  
  • Y. Akaike, O. Adriani, K. Asano, Y. Asaoka, E. Berti, G. Bigongiari, W.R. Binns, M. Bongi, P. Brogi, A. Bruno, N. Cannady, G. Castellini, C. Checchia, M.L. Cherry, G. Collazuol, G.A. de Nolfo, K. Ebisawa, A.W. Ficklin, H. Fuke, S. Gonzi, T.G. Guzik, T. Hams, K. Hibino, M. Ichimura, W. Ishizaki, M.H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H.S. Krawczynski, J.F. Krizmanic, P. Maestro, P.S. Marrocchesi, A.M. Messineo, J.W. Mitchell, S. Miyake, A.A. Moiseev, M. Mori, N. Mori, H.M. Motz, K. Munakata, S. Nakahira, J. Nishimura, M. Negro, S. Okuno, J.F. Ormes, S. Ozawa, L. Pacini, P. Papini, B.F. Rauch, S.B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, F. Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J.P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, W.V. Zober
    Advances in Space Research 2024年4月  
  • Miki Kurihara, Wataru Buz Iwakiri, Masahiro Tsujimoto, Ken Ebisawa, Shin Toriumi, Shinsuke Imada, Yohko Tsuboi, Kazuki Usui, Keith C. Gendreau, Zaven Arzoumanian
    The Astrophysical Journal 2024年4月1日  

MISC

 116
  • 松本浩典, 山崎典子, 満田和久, 篠崎慶亮, 前田良知, 粟木久光, 坪井陽子, 江副祐一郎, 山口弘悦, 佐藤浩介, 中嶋大, 深沢泰司, 大橋隆哉, 上田佳宏, 寺島雄一, 太田直美, 馬場彩, 海老沢研, 寺田幸功, 鶴剛, 常深博
    日本天文学会年会講演予稿集 2020 2020年  
  • Ken Ebisawa
    ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS XXVI 521 205-208 2019年  
    We are developing the web-based quick data analysis tools JUDO2 and UDON2 at DARTS (http: //darts.isas.jaxa.jp). JUDO2 adopts Aladin Lite to display various astronomical survey data. In particular, we have created HiPS data of Suzaku, MAXI, ASCA and Swift, and publish them from DARTS. In addition, we made various types of the constellation data in HiPS format. Recently, thanks to cooperation by ESA-sky team, the XMM fields of view (footprints) and direct links to the XMM-archive at ESA are made available in JUDO2. UDON2 allows users to extract spectra and light-curves of MAXI, Suzaku and ASCA data. Users can display favorite targetstars or sky regions in JUDO2, and jump to UDON2 to quickly analyze these targets. We are going to add JAXA's other astronomical data (e.g. Akari pointing data, Hitomi) to JUDO2 and UDON2.
  • Ken Ebisawa, Satoshi Nakahira, Takanori Sakamoto, Atsumasa Yoshida
    ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS XXVIII 523 515-518 2019年  
    CALET (CALorimetric Electron Telescope) has been installed and operational on the Japanese Experiment Module Exposed Facility of the International Space Station (ISS) since August 2015. We describe the Web analaysis system for the CALET Gamma-ray Burst Monitor (CGBM), which is publicly available from DARTS.
  • Pierre Fernique, Thomas Boch, Anais Oberto, Mark Allen, Daniel Durand, Ken Ebisawa, Bruno Merin, Jesus Salgado
    ASTRONOMICAL DATA ANALYSIS SOFTWARE AND SYSTEMS XXVI 521 46-49 2019年  
    Over the past few years the Hierarchical Progressive Survey (HiPS) has become a key method for the distribution of all -sky reference data. Today, HiPS represents about 100 TB of data, and is expected to double each year as the network of a dozen of HiPS providers including ESAC, JAXA, CADC and CDS grows. HiPS data sets are used by thousands of users per day through various HiPS aware clients: Aladin, MIZAR, Aladin Lite, and Aladin-Lite based ESASky and JUDO2. We expect that this technology will be one of the main methods for the distribution of surveys - images, catalogs and cubes - for the next decade. In this extremely fast growing environment, we will discuss why the HiPS network is an excellent candidate for long term management of all-sky reference data. We highlight how the intrinsic HiPS architecture based on the well known HEALPix geometry, a simple tile structure, straightforward distribution method based only on a basic HTTP server, and being standardised by IVOA, constitutes an extremely robust foundation for a system which will support all-sky data distribution for a long time.
  • 寺田幸功, 田代信, 田代信, 海老沢研, 深沢泰司, 飯塚亮, 勝田哲, 北口貴雄, 久保田あや, 水野恒史, 中島真也, 中澤知洋, 信川正順, 大野雅功, 太田直美, 志達めぐみ, 菅原泰晴, 高橋弘充, 田村隆幸, 田中康之, 寺島雄一, 坪井陽子, 内山秀樹, 宇野伸一郎, 渡辺伸, 山内茂雄
    日本天文学会年会講演予稿集 2018 228 2018年2月20日  

講演・口頭発表等

 14

所属学協会

 1

共同研究・競争的資金等の研究課題

 6
  • 日本学術振興会 科学研究費助成事業 2024年4月 - 2027年3月
    海老澤 研, 茅根 裕司
  • 日本学術振興会 科学研究費助成事業 基盤研究(C) 2016年4月 - 2019年3月
    海老澤 研, 辻本 匡弘, 吉田 鉄生, 中川 友進, 野村 真理子, 大須賀 健, 楠 絵莉子, 水本 岬希
  • 日本学術振興会 科学研究費助成事業 基盤研究(C) 2009年 - 2011年
    海老澤 研, 小林 尚人, 辻本 匡宏
  • 日本学術振興会 科学研究費助成事業 基盤研究(B) 2007年 - 2009年
    長瀬 文昭, 海老沢 研, 北本 俊二, 吉田 篤正, 松崎 恵一, 田村 隆幸, 矢治 健太郎, 宇野 伸一郎, 松下 恭子, 坪井 陽子, 平林 久, 辻本 匡弘, 馬場 彩, 村上 弘志, 久保田 あや, 飯塚 亮, 古田 豊, 林 壮一, 綾部 俊二, 吉田 清典, 野口 語, 川端 啓明, 宮脇 亮介, 沢田 紗衣子, 岩本 ひとみ, 吉田 鉄生, 馬場 亮輔, 菅原 泰晴, 戸塚 晃太, 朝岡 育子, 篠原 秀雄, 八木橋 伸佳, 鵜沢 明子, 楠 進吾
  • 日本学術振興会 科学研究費助成事業 国際学術研究 1992年 - 1994年
    長瀬 文昭, 田中 靖郎, 堂谷 忠靖, 石田 学, 紀伊 恒男, 伊藤 真之, 松岡 勝, 柴崎 徳明, 大橋 隆哉, 国枝 秀世, 田原 譲, 北本 俊二, 三原 建弘, 田中 靖郎, CANIZARES C., RICKER G., 鶴 剛, 粟木 久光, 河合 誠之, 吉田 篤正, SERLEMITSOS アール, 林田 清, BREON S., 海老沢 研, VOLZ S.V., KELLEY R., HELFAND D., MCCAMMON D., 常深 博, 牧島 一夫, 満田 和久, 村上 敏明, 小山 勝二, 山下 広順, 小川原 嘉明, 宮本 重徳, MUSHOTZKY R., 槇野 文命, HOLT S., 井上 一, SERLEMITSOS R., 川口 淳一郎, 中川 道夫, 藤本 光昭, 長瀬 文昭, 松尾 弘毅, 上杉 邦憲, WANG B., FEIGELSON E., GRAFFAGNINO V., REYNOLDS C., 羽部 朝男, GEHRELS N., FABBIANO G., SERLEMITSOS, RICKER G, 山内 茂雄, 池辺 靖