研究者業績

Akihiro Furuzawa

  (古澤 彰浩)

Profile Information

Affiliation
School of Medicine Faculty of Medicine, Fujita Health University
Degree
博士(理学)(名古屋大学)

J-GLOBAL ID
200901003971539256
researchmap Member ID
6000001840

Research History

 1

Papers

 24
  • 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, Takayuki Hayashi, Jan-Willem Den Herder, Ryo Iizuka, Manabu Ishida, Yoshitaka Ishisaki, Naomichi Kikuchi, Caroline A. Kilbourne, Shu Koyama, Sho Kurashima, Yoshitomo Maeda, Maxim Markevitch, Dan Mccammon, Kazuhisa Mitsuda, Hideyuki Mori, Nozomi Nakaniwa, Takashi Okajima, Stéphane 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
    Journal of Astronomical Telescopes, Instruments, and Systems, 4(2), Apr 1, 2018  Peer-reviewed
    The Soft X-ray Spectrometer 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-To 12-keV band. Extensive preflight 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 pulsar wind nebulae 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 nebula to refine the pixel-To-pixel timing and validate the absolute timing.
  • Tadayuki Takahashi, Motohide Kokubun, Kazuhisa Mitsuda, Richard L. Kelley, Takaya Ohashi, Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W. Allen, Naohisa Anabuki, Lorella Angelini, Keith Arnaud, Makoto Asai, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Philipp Azzarello, Chris Baluta, Aya Bamba, Nobutaka Bando, Marshall W. Bautz, Thomas Bialas, Roger Blandford, Kevin Boyce, Laura W. Brenneman, Gregory V. Brown, Esra Bulbul, Edward M. Cackett, Edgar Canavan, Maria Chernyakova, Meng P. Chiao, Paolo S. Coppi, Elisa Costantini, Steve O' Dell, Michael DiPirro, Chris Done, Tadayasu Dotani, John Doty, Ken Ebisawa, Megan E. Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C. Fabian, Carlo Ferrigno, Adam R. Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Stefan Funk, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C. Gallo, Poshak Gandhi, Kirk Gilmore, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Daniel Haas, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M. Harrus, Isamu Hatsukade, Takayuki Hayashi, Katsuhiro Hayashi, Kiyoshi Hayashida, Jan Willem Den Herder, Junko S. Hiraga, Kazuyuki Hirose, Ann Hornschemeier, Akio Hoshino, John P. Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Kazunori Ishibashi, Manabu Ishida, Kumi Ishikawa, Kosei Ishimura, Yoshitaka Ishisaki, Masayuki Itoh, Masachika Iwai, Naoko Iwata, Naoko Iyomoto, Chris Jewell, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Erin Kara, Jun Kataoka, Satoru Katsuda, Junichiro Katsuta, Madoka Kawaharada, Nobuyuki Kawai, Taro Kawano, Shigeo Kawasaki, Dmitry Khangulyan, Caroline A. Kilbourne, Mark Kimball
    Journal of Astronomical Telescopes, Instruments, and Systems, 4(2), Apr, 2018  Peer-reviewed
    © 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.
  • Maeda Yoshitomo, Sato Toshiki, Hayashi Takayuki, Iizuka Ryo, Angelini Lorella, Asai Ryota, Furuzawa Akihiro, Kelley Richard, Koyama Shu, Kurashima Sho, Ishida Manabu, Mori Hideyuki, Nakaniwa Nozomi, Okajima Takashi, Serlemitsos Peter J, Tsujimoto Masahiro, Yaqoob Tahir
    PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, 70(2), Mar, 2018  Peer-reviewed
    We present results of inflight calibration of the point spread function of the Soft X-ray Telescope that focuses X-rays onto the pixel array of the Soft X-ray Spectrometer system. We make a full array image of a point-like source by extracting a pulsed component of the Crab nebula emission. Within the limited statistics afforded by an exposure time of only 6.9 ks and limited knowledge of the systematic uncertainties, we find that the raytracing model of 1.'2 half-power-diameter is consistent with an image of the observed event distributions across pixels. The ratio between the Crab pulsar image and the raytracing shows scatter from pixel to pixel that is 40% or less in all except one pixel. The pixel-to-pixel ratio has a spread of 20%, on average, for the 15 edge pixels, with an averaged statistical error of 17% (1 sigma). In the central 16 pixels, the corresponding ratio is 15% with an error of 6%.
  • Hitomi Collaboration, Felix Aharonian, Hiroki Akamatsu, Fumie Akimoto, Steven W Allen, Lorella Angelini, Marc Audard, Hisamitsu Awaki, Magnus Axelsson, Aya Bamba, Marshall W Bautz, Roger Blandford, Laura W Brenneman, Gregory V Brown, Esra Bulbul, Edward M Cackett, Maria Chernyakova, Meng P Chiao, Paolo S Coppi, Elisa Costantini, Jelle de Plaa, Cor P de Vries, Jan-Willem den Herder, Chris Done, Tadayasu Dotani, Ken Ebisawa, Megan E Eckart, Teruaki Enoto, Yuichiro Ezoe, Andrew C Fabian, Carlo Ferrigno, Adam R Foster, Ryuichi Fujimoto, Yasushi Fukazawa, Akihiro Furuzawa, Massimiliano Galeazzi, Luigi C Gallo, Poshak Gandhi, Margherita Giustini, Andrea Goldwurm, Liyi Gu, Matteo Guainazzi, Yoshito Haba, Kouichi Hagino, Kenji Hamaguchi, Ilana M Harrus, Isamu Hatsukade, Katsuhiro Hayashi, Takayuki Hayashi, Kiyoshi Hayashida, Natalie Hell, Junko S Hiraga, Ann Hornschemeier, Akio Hoshino, John P Hughes, Yuto Ichinohe, Ryo Iizuka, Hajime Inoue, Yoshiyuki Inoue, Manabu Ishida, Kumi Ishikawa, Yoshitaka Ishisaki, Masachika Iwai, Jelle Kaastra, Tim Kallman, Tsuneyoshi Kamae, Jun Kataoka, Satoru Katsuda, Nobuyuki Kawai, Richard L Kelley, Caroline A Kilbourne, Takao Kitaguchi, Shunji Kitamoto, Tetsu Kitayama, Takayoshi Kohmura, Motohide Kokubun, Katsuji Koyama, Shu Koyama, Peter Kretschmar, Hans A Krimm, Aya Kubota, Hideyo Kunieda, Philippe Laurent, Shiu-Hang Lee, Maurice A Leutenegger, Olivier Limousin, Michael Loewenstein, Knox S Long, David Lumb, Greg Madejski, Yoshitomo Maeda, Daniel Maier, Kazuo Makishima, Maxim Markevitch, Hironori Matsumoto, Kyoko Matsushita, Dan McCammon, Brian R McNamara, Missagh Mehdipour, Eric D Miller, Jon M Miller, 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, Stéphane 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 Serlemtsos, Hiromi Seta, Megumi Shidatsu, Aurora Simionescu, Randall K Smith, Yang Soong, Łukasz 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, Shin Watanabe, Norbert Werner, 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, A J J Raassen
    PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, 70(2), Mar, 2018  Peer-reviewed
  • Nakajima Hiroshi, Maeda Yoshitomo, Uchida Hiroyuki, Tanaka Takaaki, Tsunemi Hiroshi, Hayashida Kiyoshi, Tsuru Takeshi G, Dotani Tadayasu, Nagino Ryo, Inoue Shota, Ozaki Masanobu, Tomida Hiroshi, Natsukari Chikara, Ueda Shutaro, Mori Koji, Yamauchi Makoto, Hatsukade Isamu, Nishioka Yusuke, Sakata Miho, Beppu Tatsuhiko, Honda Daigo, Nobukawa Masayoshi, Hiraga Junko S, Kohmura Takayoshi, Murakami Hiroshi, Nobukawa, Kumiko K, Bamba Aya, Doty John P, Iizuka Ryo, Sato Toshiki, Kurashima Sho, Nakaniwa Nozomi, Asai Ryota, Ishida Manadu, Mori Hideyuki, Soong Yang, Okajima Takashi, Serlemitsos Peter, Tawara Yuzuru, Mitsuishi Ikuyuki, Ishibashi Kazunori, Tamura Keisuke, Hayashi Takayuki, Furuzawa Akihiro, Sugita Satoshi, Miyazawa Takuya, Awaki Hisamitsu, Miller Eric D, Yamaguchi Hiroya
    PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, 70(2), Mar, 2018  Peer-reviewed
    We describe the in-orbit performance of the soft X-ray imaging system consisting of the Soft X-ray Telescope and the Soft X-ray Imager aboard Hitomi. Verification and calibration of imaging and spectroscopic performance are carried out, making the best use of the limited data of less than three weeks. Basic performance, including a large field of view of 38' x 38', is verified with the first-light image of the Perseus cluster of galaxies. Amongst the small number of observed targets, the on-minus-off pulse image for the out-of-time events of the Crab pulsar enables us to measure the half-power diameter of the telescope as similar to 1.'3. The average energy resolution measured with the onboard calibration source events at 5.89 keV is 179 +/- 3 eV in full width at half maximum. Light leak and crosstalk issues affected the effective exposure time and the effective area, respectively, because all the observations were performed before optimizing an observation schedule and the parameters for the dark-level calculation. Screening the data affected by these two issues, we measure the background level to be 5.6 x 10(-6) counts s(-1) arcmin(-2) cm(-2) in the energy band of 5-12 keV, which is seven times lower than that of the Suzaku XIS-BI.

Teaching Experience

 1

Professional Memberships

 1