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  2. Ryuichi Fujimoto

Ryuichi Fujimoto

  (藤本 龍一)

Profile Information

Affiliation
Professor, Department of Space Astronomy and Astrophysics, Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
Professor, Graduate Institute for Advanced Studies, The Graduate University for Advanced Studies (SOKENDAI)
Visiting Professor, School of Science, Tokyo Institute of Technology
Degree
Ph. D.(The University of Tokyo)
master's degree(The University of Tokyo)
Researcher number
20280555
ORCID ID
 https://orcid.org/0000-0002-2374-7073
J-GLOBAL ID
200901095989600566
researchmap Member ID
1000363020

I have been developing cryogenic high-resolution X-ray microcalorimeter spectrometers onboard X-ray astronomy satellite. It was achieved as the Resolve instrument onboard XRISM, which was launched in September, 2023.

Here are research themes I can provide. (1) Analyze high-resolution X-ray spectroscopy data obtained by XRISM satellite, and research motion of the hot gas in clusters of galaxies, in order to understand the formation of the large-scale structures of the Universe. (2) Conduct experimental studies, in anticipation of LiteBIRD mission, that aims for observing the polarization of the cosmic microwave background radiation.

Message to students: Through the research, develop an understanding of specific natural phenomena, and also learn the process to reach fundamental physics laws that underlie the complex phenomena, together with experimental and/or analytical methods.

Research Interests

 6

Research Areas

 2

Research History

 8
More

Education

 4

Committee Memberships

 2

Awards

 2

Papers

 155
  • Hishi, U., Fujimoto, R., Kunihisa, T., Takakura, S., Mitsude, T., Kamiya, K., Kotake, M., Hoshino, A., Shinozaki, K.
    Journal of Low Temperature Physics, 176(5-6), 2014  
  • Mitsuishi, I., Ezoe, Y., Ishikawa, K., Ohashi, T., Fujimoto, R., Mitsuda, K., Tsunematsu, S., Yoshida, S., Kanao, K., Murakami, M., Dipirro, M., Shirron, P.
    Cryogenics, 64, 2014  
  • Sato, Y., Sawada, K., Shinozaki, K., Sugita, H., Nishibori, T., Sato, R., Mitsuda, K., Yamasaki, N.Y., Takei, Y., Goto, K., Nakagawa, T., Fujimoto, R., Kikuchi, K., Murakami, M., Tsunematsu, S., Ootsuka, K., Kanao, K., Narasaki, K.
    Cryogenics, 64, 2014  
  • Mitsuda, K., Kelley, R.L., Boyce, K.R., Brown, G.V., Costantini, E., Di Pirro, M.J., Ezoe, Y., Fujimoto, R., Gendreau, K.C., Den Herder, J.-W., Hoshino, A., Ishisaki, Y., Kilbourne, C.A., Kitamoto, S., McCammon, D., Murakami, M., Murakami, H., Ogawa, M., Ohashi, T., Okamoto, A., Paltani, S., Pohl, M., Porter, F.S., Sato, Y., Shinozaki, K., Shirron, P.J., Sneiderman, G.A., Sugita, H., Szymkowiak, A., Takei, Y., Tamagawa, T., Tashiro, M., Terada, Y., Tsujimoto, M., De Vries, C., Yamasaki, N.Y.
    Journal of Low Temperature Physics, 167(5-6), 2012  
  • Hoshino, A., Yatsu, T., Kunihisa, T., Koi, N., Notsuke, M., Fujimoto, R., Yamamoto, R., Shinozaki, K.
    Journal of Low Temperature Physics, 167(3-4), 2012  
  • Ezoe, Y., Fujimoto, R., Yamasaki, N.Y., Mitsuda, K., Ohashi, T., Ishikawa, K., Oishi, S., Miyoshi, Y., Terada, N., Futaana, Y., Porter, F.S., Brown, G.V.
    Astronomische Nachrichten, 333(4), 2012  
  • Seta, H., Tashiro, M.S., Ishisaki, Y., Tsujimoto, M., Shimoda, Y., Abe, Y., Yasuda, T., Takeda, S., Asahina, M., Hiyama, Y., Yamaguchi, S., Terada, Y., Boyce, K.R., Porter, F.S., Kilbourne, C.A., Kelley, R.L., Fujimoto, R., Takei, Y., Mitsuda, K., Matsuda, K., Masukawa, K.
    IEEE Transactions on Nuclear Science, 59(2), 2012  
  • Ezoe, Y., Ishikawa, K., Ohashi, T., Yamaguchi, H., Mitsuda, K., Fujimoto, R., Murakami, M., Kanao, K., Yoshida, S., Tsunematsu, S., Dipirro, M., Shirron, P.
    Cryogenics, 52(4-6), 2012  
  • Sato, Y., Shinozaki, K., Sugita, H., Mitsuda, K., Yamasaki, N.Y., Takei, Y., Nakagawa, T., Fujimoto, R., Murakami, M., Tsunematsu, S., Otsuka, K., Yoshida, S., Kanao, K., Narasaki, K.
    Cryogenics, 52(4-6), 2012  
  • den Herder, J.-W., Piro, L., Ohashi, T., Kouveliotou, C., Hartmann, D.H., Kaastra, J.S., Amati, L., Andersen, M.I., Arnaud, M., Att{\'e}ia, J.-L., B, ler, S., Barbera, M., Barcons, X., Barthelmy, S., Basa, S., Basso, S., Boer, M., Branchini, E., Br, uardi-Raymont, G., Borgani, S., Boyarsky, A., Brunetti, G., Budtz-Jorgensen, C., Burrows, D., Butler, N., Campana, S., Caroli, E., Ceballos, M., Christensen, F., Churazov, E., Comastri, A., Colasanti, L., Cole, R., Content, R., Corsi, A., Costantini, E., Conconi, P., Cusumano, G., de Plaa, J., De Rosa, A., Del Santo, M., Di Cosimo, S., De Pasquale, M., Doriese, R., Ettori, S., Evans, P., Ezoe, Y., Ferrari, L., Finger, H., Figueroa-Feliciano, T., Friedrich, P., Fujimoto, R., Furuzawa, A., Fynbo, J., Gatti, F., Galeazzi, M., Gehrels, N., Gendre, B., Ghirl, a, G., Ghisellini, G., Gilfanov, M., Giommi, P., Girardi, M., Grindlay, J., Cocchi, M., Godet, O., Guedel, M., Haardt, F., den Hartog, R., Hepburn, I., Hermsen, W., Hjorth, J., Hoekstra, H., Holl, , A., Hornstrup, A., van der Horst, A., Hoshino, A., in{'}t Z, , J., Irwin, K., Ishisaki, Y., Jonker, P., Kitayama, T., Kawahara, H., Kawai, N., Kelley, R., Kilbourne, C., de Korte, P., Kusenko, A., Kuvvetli, I., Labanti, M., Macculi, C., Maiolino, R., Hesse, M.M., Matsushita, K., Mazzotta, P., McCammon, D., M{\'e}ndez, M., Mignani, R., Mineo, T., Mitsuda, K., Mushotzky, R., Molendi, S., Moscardini, L., Natalucci, L., Nicastro, F., O{'}Brien, P., Osborne, J., Paerels, F., Page, M., Paltani, S., Pedersen, K., Perinati, E., Ponman, T., Pointecouteau, E., Predehl, P., Porter, S., Rasmussen, A., Rauw, G., R{\"o}ttgering, H., Roncarelli, M., Rosati, P., Quadrini, E., Ruchayskiy, O., Salvaterra, R., Sasaki, S., Sato, K., Savaglio, S., Schaye, J., Sciortino, S., Shaposhnikov, M., Sharples, R., Shinozaki, K., Spiga, D., Sunyaev, R., Suto, Y., Takei, Y., Tanvir, N., Tashiro, M., Tamura, T., Tawara, Y., Troja, E., Tsujimoto, M., Tsuru, T., Ubertini, P., Ullom, J., Ursino, E., Verbunt, F., van de Voort, F., Viel, M., Wachter, S., Watson, D., Weisskopf, M., Werner, N., White, N., Willingale, R., Wijers, R., Yamasaki, N., Yoshikawa, K., Zane, S.
    Experimental Astronomy, 34(2), 2012  
  • Ezoe, Y., Ishikawa, K., Ohashi, T., Yamasaki, N.Y., Mitsuda, K., Fujimoto, R., Miyoshi, Y., Terada, N., Uchiyama, Y., Futaana, Y.
    Advances in Space Research, 47(3), 2011  
  • J. W. Den Herder, R. L. Kelley, K. Mitsuda, L. Piro, S. R. Bandler, P. Bastia, K. R. Boyce, M. Bruin, J. A. Chervenak, L. Colasanti, W. B. Doriese, M. DiPirro, M. E. Eckart, Y. Ezoe, E. Figueroa-Feliciano, L. Ferrari, R. Fujimoto, F. Gatti, K. C. Gendreau, L. Gottardi, R. Den Hartog, G. C. Hilton, H. Hoevers, K. D. Irwin, Y. Ishisaki, A. Kashani, C. A. Kilbourne, P. De Korte, J. Van, Der Kuur, C. MacCuli, T. Mineo, J. H. Nieland, T. Ohashi, S. Paltani, E. Perinati, F. S. Porter, P. J. Shirron, S. J. Smith, Y. Takei, M. Tashiro, G. Torrioli, M. Tsujimoto, H. Van Weers, N. Y. Yamasaki
    Proceedings of SPIE - The International Society for Optical Engineering, 7732, Oct 19, 2010  
    One of the instruments on the International X-ray Observatory (IXO), under study with NASA, ESA and JAXA, is the X-ray Microcalorimeter Spectrometer (XMS). This instrument, which will provide high spectral resolution images, is based on X-ray micro-calorimeters with Transition Edge Sensor (TES) with absorbers that consist of metal and semimetal layers and a multiplexed SQUID readout. The requirements for this instrument are demanding. In the central array (40 x 40 pixels) an energy resolution of < 2.5 eV is required, whereas the energy resolution of the outer array is more relaxed (∼ 10 eV) but the detection elements have to be a factor 16 larger in order to keep the number of read-out channels acceptable for a cryogenic instrument. Due to the large collection area of the IXO optics, the XMS instrument must be capable of processing high counting rates, while maintaining the spectral resolution and a low deadtime. In addition, an anti-coincidence detector is required to suppress the particle-induced background. In this paper we will summarize the instrument status and performance. We will describe the results of design studies for the focal plane assembly and the cooling systems. Also the system and its required spacecraft resources will be given. © 2010 SPIE.
  • Ryuichi Fujimoto, Kazuhisa Mitsuda, Noriko Yamasaki, Yoh Takei, Masahiro Tsujimoto, Hiroyuki Sugita, Yoichi Sato, Keisuke Shinozaki, Atsushi Okamoto, Takaya Ohashi, Yoshitaka Ishisaki, Yuichiro Ezoe, Kumi Ishikawa, Masahide Murakami, Shunji Kitamoto, Hiroshi Murakami, Toru Tamagawa, Madoka Kawaharada, Hiroya Yamaguchi, Kosuke Sato, Akio Hoshino, Kenichi Kanao, Seiji Yoshida, Mikio Miyaoka, Michael DiPirro, Peter Shirron, Gary Sneiderman, Richard L. Kelley, F. Scott Porter, Caroline A. Kilbourne, John Crow, Andrea Mattern, Ali Kashani, Dan McCammon
    SPACE TELESCOPES AND INSTRUMENTATION 2010: ULTRAVIOLET TO GAMMA RAY, 7732(9) 488-493, 2010  Peer-reviewed
    The Soft X-ray Spectrometer (SXS) is a cryogenic high resolution X-ray spectrometer onboard the X-ray astronomy satellite ASTRO-H. The detector array is cooled down to 50 mK using a 3-stage adiabatic demagnetization refrigerator (ADR). The cooling chain from room temperature to the ADR heat-sink is composed of superfluid liquid He, a He-4 Joule-Thomson cryocooler, and 2-stage Stirling cryocoolers. It is designed to keep 30 L of liquid He for more than 3 years in the nominal case. It is also designed with redundant subsystems throughout from room temperature to the ADR heat-sink, to alleviate failure of a single cryocooler or loss of liquid He.
  • F. S. Porter, J. S. Adams, G. V. Brown, J. A. Chervenak, M. P. Chiao, R. Fujimoto, Y. Ishisaki, R. L. Kelley, C. A. Kilbourne, D. McCammon, K. Mitsuda, T. Ohashi, A. E. Szymkowiak, Y. Takei, M. Tashiro, N. Yamasaki
    Proceedings of SPIE - The International Society for Optical Engineering, 7732, 2010  Peer-reviewed
    The Soft X-ray Spectrometer (SXS) instrument on the Astro-H observatory is based on a 36 pixel x-ray calorimeter array cooled to 50 mK in a sophisticated spaceflight cryostat. The SXS is a true spatial-spectral instrument, where each spatially discrete pixel functions as a high-resolution spectrometer. Here we discuss the SXS detector subsystem that includes the detector array, the anticoincidence detector, the first stage amplifiers, the thermal and mechanical staging of the detector, and the cryogenic bias electronics. The design of the SXS detector subsystem has significant heritage from the Suzaku/XRS instrument but has some important modifications that increase performance margins and simplify the focal plane assembly. Notable improvements include x-ray absorbers with significantly lower heat capacity, improved load resistors, improved thermometry, and a decreased sensitivity to thermal radiation. These modifications have yielded an energy resolution of 3.5-4.0 eV FWHM at 6 keV for representative devices in the laboratory, giving considerable margin against the 7 eV instrument requirement. We expect similar performance in flight. © 2010 SPIE.
  • Fujimoto Ryuichi, Sato Kosuke, Wada Akane, Yatsu Takahiro, Hoshino Akio, Murakami Toshio, Shinozaki Keisuke
    AIP Conference Proceedings, 1279 309-311, Jan 1, 2010  
  • Kazuhisa Mitsuda, Richard L. Kelley, Kevin R. Boyce, Gregory V. Brown, Elisa Costantini, Michael J. DiPirro, Yuichiro Ezoe, Ryuichi Fujimoto, Keith C. Gendreau, Jan-Willem Den Herder, Akio Hoshino, Yoshitaka Ishisaki, Caroline A. Kilbourne, Shunji Kitamoto, Dan McCammon, Masahide Murakami, Hiroshi Murakami, Mina Ogawa, Takaya Ohashi, Atsushi Okamoto, Stéphane Paltani, Martin Pohl, F. Scott Porter, Yoichi Sato, Keisuke Shinozaki, Peter J. Shirron, Gary A. Sneiderman, Hiroyuki Sugita, Andrew Szymkowiak, Yoh Takei, Toru Tamagawa, Makoto Tashiro, Yukikatsu Terada, Masahiro Tsujimoto, Cor De Vries, Hiroya Yamaguchi, Noriko Y. Yamasaki
    Proceedings of SPIE - The International Society for Optical Engineering, 7732, 2010  Peer-reviewed
    We present the science and an overview of the Soft X-ray Spectrometer onboard the ASTRO-H mission with emphasis on the detector system. The SXS consists of X-ray focusing mirrors and a microcalorimeter array and is developed by international collaboration lead by JAXA and NASA with European participation. The detector is a 6×6 format microcalorimeter array operated at a cryogenic temperature of 50 mK and covers a 3′ ×3′ filed of view of the X-ray telescope of 5.6 m focal length. We expect an energy resolution better than 7 eV (FWHM, requirement) with a goal of 4 eV. The effective area of the instrument will be 225 cm2 at 7 keV by a factor of about two larger than that of the X-ray microcalorimeter on board Suzaku. One of the main scientific objectives of the SXS is to investigate turbulent and/or macroscopic motions of hot gas in clusters of galaxies. © 2010 SPIE.
  • Ezoe, Y., Ebisawa, K., Yamasaki, N.Y., Mitsuda, K., Yoshitake, H., Terada, N., Miyoshi, Y., Fujimoto, R.
    Publications of the Astronomical Society of Japan, 62(4) 981-986, 2010  
    We report on the detection of a time variable O VII line emission in a deep 100 ks Suzaku X-ray Imaging Spectrometer spectrum of the galactic ridge X-ray emission. The observed line intensity is too strong (11 +/- 2 line unit or photon cm(-2) s(-1) sr(-1)) to be emitted inside the heavily obscured galactic disk. It showed a factor of two time variation that showed a significant (similar to 4 sigma) correlation with the solar-wind O7+ ion flux. The high line intensity and good time correlation with the solar wind strongly suggests that it originated from geocoronal solar-wind charge-exchange emission. We discuss the X-ray line intensity while considering a line-of-sight direction and also theoretical distribution models of the neutral hydrogen and solar wind around Earth. Our results indicate that X-ray observations of geocoronal solar-wind charge-exchange emission can be used to constrain these models.
  • Shinozaki, K., Mitsuda, K., Yamasaki, N.Y., Takei, Y., Masui, K., Asano, K., Ohashi, T., Ezoe, Y., Ishisaki, Y., Fujimoto, R., Sato, K., Kanao, K., Yoshida, S.
    Cryogenics, 50(9), 2010  
  • Fujimoto, R., Mitsuda, K., Yamasaki, N., Takei, Y., Tsujimoto, M., Sugita, H., Sato, Y., Shinozaki, K., Ohashi, T., Ishisaki, Y., Ezoe, Y., Murakami, M., Kitamoto, S., Murakami, H., Tamagawa, T., Kawaharada, M., Yamaguchi, H., Sato, K., Kanao, K., Yoshida, S., Dipirro, M., Shirron, P., Sneiderman, G., Kelley, R.L., Scott Porter, F., Kilbourne, C.A., Crow, J., Mattern, A., Kashani, A., McCammon, D., Herder, J.-W.D.
    Cryogenics, 50(9) 488-493, 2010  
  • Sato, Y., Sugita, H., Mitsuda, K., Nakagawa, T., Fujimoto, R., Murakami, M., Otsuka, K., Tsunematsu, S., Kanao, K., Narasaki, K.
    Cryogenics, 50(9) 500-506, 2010  
    The Soft X-ray Spectrometer (SXS) is a high-resolution spectrometer with an X-ray micro-calorimeter array onboard the Japanese X-ray astronomy satellite Astro-H, planned for launch in 2013. The micro-calorimeter is operated at cryogenic temperature of 50 mK provided by the Adiabatic Demagnetization Refrigerator (ADR) with a heat sink of 1.3 K liquid helium stored in the SXS Dewar. To extend the liquid helium lifetime to over 3 years in orbit, two types of mechanical cryocoolers are installed: 20 K-class double-staged Stirling (2ST) coolers and a 1 K-class Joule-Thomson (JT) cooler. Improvement of mechanical cryocoolers has been investigated and verified for higher reliability and cooling performance. The engineering model (EM) of upgraded mechanical cryocoolers was fabricated for a long lifetime test. The required cooling power of 200 mW at 20K for the 2ST cooler and 10 mW at 1.7 K for the JT cooler are achieved by EM test. (c) 2010 Elsevier Ltd. All rights reserved.
  • Ishikawa, K., Ezoe, Y., Yamaguchi, H., Mitsuishi, I., Yoshitake, H., Mitsuda, K., Fujimoto, R., Ohashi, T., Murakami, M., Kanao, K.-I., Yoshida, S., Tsunematsu, S., Dipirro, M., Shirron, P.
    Cryogenics, 50(9), 2010  
  • R. L. Kelley, S. R. Bandler, W. B. Doriese, Y. Ezoe, R. Fujimoto, L. Gottardi, R. den Hartog, J-W den Herder, H. Hoevers, K. Irwin, Y. Ishisaki, C. A. Kilbourne, P. de Korte, J. van der Kuur, K. Mitsuda, T. Ohashi, L. Piro, F. S. Porter, K. Sato, K. Shinozaki, P. Shirron, S. J. Smith, Y. Takei, P. Whitehouse, N. Y. Yamasaki
    LOW TEMPERATURE DETECTORS LTD 13, 1185 757-+, 2009  Peer-reviewed
    The International X-Ray Observatory (IXO) is under formulation by NASA, ESA and JAXA for deployment in 2022. IXO emerged over the last 18 months as the NASA Constellation-X and ESA/JAXA X-Ray Evolving Universe Spectrometer (XEUS) missions were combined. The driving performance requirements for the X-Ray Microcalorimeter Spectrometer (XMS) are a spectral resolution of 2.5 eV over the central 2'x2' in the 0.3-7.0 keV band, and 10 eV to the edge of the 5'x5' field of view (FOV). The XMS is now based on a microcalorimeter array of Transition-Edge Sensor (TES) thermometers with Au/Bi absorbers and a SQUID MUX readout. One of the concepts studied as part of the mission formulation has a core 40x40 array corresponding to a 2'x2' FOV with 3 '' pixels surrounded by an outer, annular 52 x 52 array of 6 '' pixels that extends the field of view to 5.4'x5.4' with better than 10 eV resolution. There are several options for implementing the readout and cooling system of the XMS under study in the US, Europe and Japan. The ADR system will have from two to five stages depending on the performance of the cryocooler. Mechanical coolers with sufficient cooling power at 4K are available now, and similar to 2K coolers are under development. In this paper we give an overview of the XMS instrument, and some of the tradeoffs to be addressed for this observatory instrument.
  • Yoshino, T., Mitsuda, K., Yamasaki, N.Y., Takei, Y., Hagihara, T., Masui, K., Bauer, M., McCammon, D., Fujimoto, R., Wang, Q.D., Yao, Y.
    Publications of the Astronomical Society of Japan, 61(4), 2009  
  • Kazuhisa Mitsuda, Noriko Y. Yamasaki, Keisuke Shinozaki, Yoh Takei, Takao Nakagawai, Hiroyuki Sugitai, Yohichi Satoh, Ryuichi Fujimoto, Takaya Ohashi, Yoshitaka Ishisaki, Yuichiro Ezoe, Masahide Murakami, Makoto Tashiro, Yukikatsu Terada, Shunji Kitamoto, Toru Tamagawa, Madoka Kawaharada, Tatehiro Mihara, Richard L. Kelley, Caroline A. Kilbourne, F. Scott Porter, Peter J. Shirron, Michael J. Dipirro, Dan Mccammon, Jan-Willem Den Herder
    Proceedings of SPIE - The International Society for Optical Engineering, 7011, 2008  Peer-reviewed
    The Soft X-ray Spectrometer (SXS) onboard the NeXT (New exploration X-ray Telescope) is an X-ray spectrometer utilizing an X-ray microcalorimeter array. Combined with the soft X-ray telescope of 6 m focal length, the instrument will have a ∼ 290cm2 effective at 6.7 keV. With the large effective area and the energy resolution as good as 6 eV (FWHM), the instrument is very suited for the high-resolution spectroscopy of iron K emission line. One of the major scientific objectives of SXS is to determine turbulent and/or macroscopic motions of the hot gas in clusters of galaxies of up to z ∼ 1. The instruments will use 6 × 6 or 8 × 8 format microcalorimeter array which is similar to that of Suzaku XRS. The detector will be cooled to a cryogenic temperature of 50 mK by multi-stage cooling system consisting of adiabatic demagnetization refrigerator, super fluid He, a 3He Joule Thomson cooler, and double-stage Stirling cycle cooler.
  • J. W. Den Herder, R. Kelley, D. Mccammon, K. Mitsuda, H. Aarts, C. V. Van Baren, M. Buntov, E. Churazov, E. Costantini, J. Cottam, L. Dubbeldam, Y. Ezoe, P. Friedrichs, R. Fujimoto, M. Gilvanov, Y. Ishisaki, J. Kaastra, C. Kilbourne, K. Kuntz, R. Mushotzky, M. Murakami, T. Nakagawa, T. Ohashi, M. Pavlinsky, R. Petre, Scott Porter, P. Predehl, Y. Sato, N. Semea, K. Shinozaki, R. Smith, S. Snowden, R. Sunyaev, H. Sugita, Y. Takei, A. Tkachenko, J. Vink, C. P. De Vries, N. White, N. Yamasaki, F. Zwart
    Proceedings of SPIE - The International Society for Optical Engineering, 7011, 2008  
    Spatially resolved X-ray spectroscopy with high spectral resolution allows the study of astrophysical processes in extended sources with unprecedented sensitivity. This includes the measurement of abundances, temperatures, densities, ionisation stages as well as turbulence and velocity structures in these sources. An X-ray calorimeter is planned for the Russian mission Spektr Röntgen-Gamma (SRG), to be launched in 2011. During the first half year (pointed phase) it will study the dynamics and composition of of the hot gas in massive clusters of galaxies and in supernova remnants (SNR). During the survey phase it will produce the first all sky maps of line-rich spectra of the interstellar medium (ISM). Spectral analysis will be feasible for typically every 5° × 5° region on the sky. Considering the very short time-scale for the development of this instrument it consists of a combination of well developed systems. For the optics an extra eROSITA mirror, also part of the Spektr-RG payload, will be used. The detector will be based on spare parts of the detector flown on Suzaku combined with a rebuild of the electronics and the cooler will be based on the design for the Japanese mission NeXT. In this paper we will present the science and give an overview of the instrument.
  • K. Shinozaki, K. Mitsuda, N. Y. Yamasaki, Y. Takei, M. Dipirro, Y. Ezoe, R. Fujimoto, J. W. Den Herder, M. Hirabayashi, Y. Ishisaki, K. Kanao, M. Kawaharada, R. Kelley, C. Kilbourne, S. Kitamoto, D. McCammon, T. Mihara, M. Murakami, T. Nakagawa, T. Ohashi, F. S. Porter, Y. Satoh, P. Shirron, H. Sugita, T. Tamagawa, M. Tashiro, S. Yoshida
    Proceedings of SPIE - The International Society for Optical Engineering, 7011, 2008  
    The SXS (Soft X-ray Spectrometer) onboard the coming Japanese X-ray satellite NeXT (New Exploration Xray Telescope) and the SXC (Spectrum-RG X-ray Calorimeter) in Spectrum-RG mission are microcalorimeter array spectrometers which will achieve high spectral resolution of ~ 6 eV in 0.3-10.0 keV energy band. These spectrometers are well-suited to address key problems in high-energy astrophysics. To achieve these high spectral sensitivities, these detectors require to be operated under 50 mK by using very efficient cooling systems including adiabatic demagnetization refrigerator (ADR). For both missions, we propose a two-stage series ADR as a cooling system below 1 K, in which two units of ADR consists of magnetic cooling material, a superconducting magnet, and a heat switch are operated step by step. Three designs of the ADR are proposed for SXS/SXC. In all three designs, ADR can attain the required hold time of 23 hours at 50 mK and cooling power of 0.4μW with a low magnetic fields (1.5/1.5 Tesla or 2.0/3.0 Tesla) in a small configuration (180 mmφ× 319 mm in length). We also fabricated a new portable refrigerator for a technology investigation of two-stage ADR. Two units of ADR have been installed at the bottom of liquid He tank. By using this dewar, important technologies such as an operation of two-stage cooling cycle, tight temperature control less than 1 μK (in rms) stability, a magnetic shielding, saltpills, and gas-gap heat switches are evaluated.
  • Tadayuki Takahashi, Richard Kelley, Kazuhisa Mitsuda, Hideyo Kunieda, Robert Petre, Nicholas White, Tadayasu Dotani, Ryuichi Fujimoto, Yasushi Fukazawa, Kiyoshi Hayashida, Manabu Ishida, Yoshitaka Ishisaki, Motohide Kokubun, Kazuo Makishima, Katsuji Koyama, Greg M. Madejski, Koji Mori, Richard Mushotzky, Kazuhiro Nakazawa, Yasushi Ogasaka, Takaya Ohashi, Masanobu Ozaki, Hiroyasu Tajima, Makoto Tashiro, Yukikatsu Terada, Hiroshi Tsunemi, Takeshi Go Tsuru, Yoshihiro Ueda, Noriko Yamasaki, Shin Watanabe
    Proceedings of SPIE - The International Society for Optical Engineering, 7011, 2008  
    The NeXT (New exploration X-ray Telescope), the new Japanese X-ray Astronomy Satellite following Suzakii, is an international X-ray mission which is currently planed for launch in 2013. NeXT is a combination of wide band X-ray spectroscopy (3-80 keV) provided by multi-layer coating, focusing hard X-ray mirrors and hard X-ray imaging detectors, and high energy-resolution soft X-ray spectroscopy (0.3-10 keV) provided by thin-foil X-ray optics and a micro-calorimeter array. The mission will also carry an X-ray CCD camera as a focal plane detector for a soft X-ray telescope and a non-focusing soft gamma-ray detector. With these instruments, NeXT covers very wide energy range from 0.3 keV to 600 keV. The micro-calorimeter system will be developed by international collaboration lead by ISAS/JAXA and NASA. The simultaneous broad bandpass, coupled with high spectral resolution of ΔE ∼7 eV by the micro-calorimeter will enable a wide variety of important science themes to be pursued.
  • Miller, E.D., Tsunemi, H., Bautz, M.W., McCammon, D., Fujimoto, R., Hughes, J.P., Katsuda, S., Kokubun, M., Mitsuda, K., Porter, F.S., Takei, Y., Tsuboi, Y., Yamasaki, N.Y.
    Publications of the Astronomical Society of Japan, 60(SPEC. ISS. 1), 2008  
  • Kimura, S., Masui, K., Takei, Y., Mitsuda, K., Yamasaki, N.Y., Fujimoto, R., Morooka, T., Nakayama, S.
    Journal of Low Temperature Physics, 151(3-4 PART 2), 2008  
  • Uchiyama, Y., Maeda, Y., Ebara, M., Fujimoto, R., Ishisaki, Y., Ishida, M., Iizuka, R., Ushio, M., Inoue, H., Okada, S., Mori, H., Ozaki, M.
    Publications of the Astronomical Society of Japan, 60(SPEC. ISS. 1) S35-S41, 2008  
  • Shirai, H., Fukazawa, Y., Sasada, M., Ohno, M., Yonetoku, D., Yokota, S., Fujimoto, R., Murakami, T., Terashima, Y., Awaki, H., Ikeda, S., Ozawa, M., Tsuru, T.G.
    Publications of the Astronomical Society of Japan, 60(SPEC. ISS. 1), 2008  
  • T. Dotani, K. Mitsuda, M. Bautz, H. Inoue, R. L. Kelley, K. Koyama, H. Kunieda, K. Makishima, Y. Ogawara, R. Petre, T. Takahashi, H. Tsunemi, N. E. White, N. Anabuki, L. Angelini, K. Arnaud, H. Awaki, A. Bamba, K. Boyce, G. V. Brown, K. -W. Chan, J. Cottam, J. Doty, K. Ebisawa, Y. Ezoe, A. C. Fabian, E. Figueroa, R. Fujimoto, Y. Fukazawa, T. Furusho, A. Furuzawa, K. Gendreau, R. E. Griffiths, Y. Haba, K. Hamaguchi, l. Harrus, G. Hasinger, I. Hatsukade, K. Hayashida, P. J. Henry, J. S. Hiraga, S. S. Holt, A. Hornschemeier, J. P. Hughes, U. Hwang, M. Ishida, Y. Ishisaki, N. Isobe, M. Itoh, N. Iyomoto, S. M. Kahn, T. Kamae, H. Katagiri, J. Kataoka, H. Katayama, N. Kawai, M. Kawaharada, C. Kilbourne, K. Kinugasa, S. Kissel, S. Kitamoto, M. Kohama, T. Kohmura, M. Kokubun, T. Kotani, J. Kotoku, A. Kubota, G. M. Madejski, Y. Maeda, F. Makino, A. Markowitz, C. Matsumoto, H. Matsumoto, M. Matsuoka, K. Matsushita, D. McCammon, T. Mihara, K. Misaki, E. Miyata, T. Mizuno, K. Mori, H. Mori, M. Morii, H. Moseley, K. Mukai, H. Murakami, T. Murakami, R. Mushotzky, F. Nagase, M. Namiki, H. Negoro, K. Nakazawa, J. A. Nousek, T. Okajima, Y. Ogasaka, T. Ohashi, T. Oshima, N. Ota, M. Ozaki, H. Ozawa, A. N. Parmar, W. D. Pence, F. Scott Porter, J. N. Reeves, G. R. Ricker, L. Sakurai, W. T. Sanders, A. Senda, P. Serlemitsos, R. Shibata, K. Shinozaki, Y. Soong, R. Smith, M. Suzuki, A. E. Szymkowiak, H. Takahashi, Y. Takei, T. Tamagawa, K. Tamura, T. Tamura, Y. Tanaka, M. Tashiro, Y. Tawara, Y. Terada, Y. Terashima, H. Tomida, K. Torii, Y. Tsuboi, Y. Tsujimoto, T. Tsuru, M. J. L. Turner, Y. Uchiyama, Y. Ueda, S. Ueno, M. Ueno, S. Uno, Y. Urata, S. Watanabe, N. Yamamoto, K. Yamaoka, N. Y. Yamasaki, K. Yamashita, M. Yamauchi, S. Yajmauchi, T. Yaqoob, D. Yonetoku, A. Yoshida
    2007 IEEE NUCLEAR SCIENCE SYMPOSIUM CONFERENCE RECORD, VOLS 1-11, 2526-+, 2007  Peer-reviewed
    We report in-flight status of the X-ray detectors on board the Suzaku observatory, the 5th X-ray astronomy satellite of Japan launched on July 10, 2005. Suzaku is equipped with two types of instruments: one is the X-ray Imaging Spectrometers (XISs) and the other is Hard X-ray Detector (HXD). XIS utilizes the X-ray CCD camera in combination with the grazing-incidence X-ray telescope. HXD is a non-imaging, hybrid detector utilizing Si PIN diodes and GSO/BGO phoswich counters. Suzaku takes a low-earth, circular orbit with an altitude of 560 km and an inclination of 31 deg. This means that Suzaku goes through the south atlantic anomaly about 1/3 of its revolutions. This has a large impact on the in-flight performance of XIS and HXD, which is reported in detail in the present paper.
  • Y. Fukazawa, H. Shirai, M. Ohno, D. Yonetoku, S. Yokota, T. Murakami, K. Iwasawa, Y. Terashima, H. Awaki, T. Tsuru, M. Ozawa, R. Fujimoto
    CENTRAL ENGINE OF ACTIVE GALACTIC NUCLEI, 373 165-+, 2007  Peer-reviewed
    Here we report the preliminary results on the Suzaku observations of the Seyfert 2 galaxy NGC 4388. The longest high-sensitibity wide-band Xray observation of this object for the first time revealed the time variability of spectra and the complex Fe-K line features.
  • Takei, Y., Henry, J.P., Finoguenov, A., Mitsuda, K., Tamura, T., Fujimoto, R., Briel, U.G.
    Astrophysical Journal, 655(2 I), 2007  
  • Mitsuda, K., Bautz, M., Inoue, H., Kelley, R.L., Koyama, K., Kunieda, H., Makishima, K., Ogawara, Y., Petre, R., Takahashi, T., Tsunemi, H., White, N.E., Anabuki, N., Angelini, L., Arnaud, K., Awaki, H., Bamba, A., Boyce, K., Brown, G.V., Chan, K.-W., Cottam, J., Dotani, T., Doty, J., Ebisawa, K., Ezoe, Y., Fabian, A.C., Figueroa, E., Fujimoto, R., Fukazawa, Y., Furusho, T., Furuzawa, A., Gendreau, K., Griffiths, R.E., Haba, Y., Hamaguchi, K., Harrus, I., Hasinger, G., Hatsukade, I., Hayashida, K., Henry, P.J., Hiraga, J.S., Holt, S.S., Hornschemeier, A., Hughes, J.P., Hwang, U., Ishida, M., Ishisaki, Y., Isobe, N., Itoh, M., Iyomoto, N., Kahn, S.M., Kamae, T., Katagiri, H., Kataoka, J., Katayama, H., Kawai, N., Kllbourne, C., Kinugasa, K., Klssel, S., Kitamoto, S., Kohama, M., Kohmura, T., Kokubun, M., Kotani, T., Kotoku, J., Kubota, A., Madejski, G.M., Maeda, Y., Makino, F., Markowitz, A., Matsumoto, C., Matsumoto, H., Matsuoka, M., Matsushita, K., Mccammon, D., Mihara, T., Misakl, K., Miyata, E., Mizuno, T., Mori, K., Mori, H., Morii, M., Moseley, H., Mukai, K., Murakami, H., Murakami, T., Mushotzky, R., Nagase, F., Namiki, M., Negoro, H., Nakazawa, K., Nousek, J.A., Okajima, T., Ogasaka, Y., Ohashi, T., Oshima, T., Ota, N., Ozaki, M., Ozawa, H., Parmar, A.N., Pence, W.D., Porter, F.S., Reeves, J.N., Ricker, G.R., Sakurai, I., Sanders, W.T., Senda, A., Serlemitsos, P., Shibata, R., Soong, Y., Smith, R., Suzuki, M., Szymkowiak, A.E., Takahashi, H., Tamagawa, T., Tamura, K., Tamura, T., Tanaka, Y., Tashiro, M., Tawara, Y., Terada, Y., Terashima, Y., Tomida, H., Torii, K., Tsuboi, Y., Tsujimoto, M., Tsuru, T.G., Turner, M.J.L., Ueda, Y., Ueno, S., Ueno, M., Uno, S., Urata, Y., Watanabe, S., Yamamoto, N., Yamaoka, K., Yamasaki, N.Y., Yamashita, K., Yamauchi, M., Yamauchi, S., Yaqoob, T., Yonetoku, D., Yoshida, A.
    Publications of the Astronomical Society of Japan, 59(1 SPEC. ISS.), 2007  
    High-sensitivity wide-band X-ray spectroscopy is the key feature of the Suzaku X-ray observatory, launched on 2005 July 10. This paper summarizes the spacecraft, in-orbit performance, operations, and data processing that are related to observations. The scientific instruments, the high-throughput X-ray telescopes, X-ray CCD cameras, non-imaging hard X-ray detector are also described. © 2007. Astronomical Society of Japan.
  • Takei, Y., Ohashi, T., Henry, J.P., Mitsuda, K., Fujimoto, R., Tamura, T., Yamasaki, N.Y., Hayashida, K., Tawa, N., Matsushita, K., Bautz, M.W., Hughes, J.P., Madejski, G.M., Kelley, R.L., Arnaud, K.A.
    ESO Astrophysics Symposia, 2007, 2007  
  • Fujimoto, R., Mitsuda, K., Mccammon, D., Takei, Y., Bauer, M., Ishisaki, Y., Porter, F.S., Yamaguchi, H., Hayashida, K., Yamasaki, N.Y.
    Progress of Theoretical Physics Supplement, 59(169) 71-74, 2007  
  • Ishisaki, Y., Maeda, Y., Fujimoto, R., Ozaki, M., Ebisawa, K., Takahashi, T., Ueda, Y., Ogasaka, Y., Ptak, A., Mukai, K., Hamaguchi, K., Hirayama, M., Kotani, T., Kubo, H., Shibata, R., Ebara, M., Furuzawa, A., Iizuka, R., Inoue, H., Mori, H., Okada, S., Yokoyama, Y., Matsumoto, H., Nakajima, H., Yamaguchi, H., Anabuki, N., Tawa, N., Nagai, M., Katsuda, S., Hayashida, K., Bamba, A., Miller, E.D., Sato, K., Yamasaki, N.Y.
    Publications of the Astronomical Society of Japan, 59(1 SPEC. ISS.) S113-S132, 2007  
  • Smith, R.K., Bautz, M.W., Edgar, R.J., Fujimoto, R., Hamaguchi, K., Hughes, J.P., Ishida, M., Kelley, R., Kllbourne, C.A., Kuntz, K.D., McCammon, D., Miller, E., Mitsuda, K., Mukai, K., Plucinsky, P.P., Porter, F.S., Snowden, S.L., Takei, Y., Terada, Y., Tsuboi, Y., Yamasaki, N.Y.
    Publications of the Astronomical Society of Japan, 59(1 SPEC. ISS.), 2007  
  • Shirron, P.J., DiPirro, M.J., Panek, J., Kelley, R., Mitsuda, K., Fujimoto, R., Hirabayashi, M., McCammon, D.
    Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 559(2), 2006  
  • Yoshino, T., Yoshida, K., Hagihara, T., Sato, K., Morita, U., Ishisaki, Y., Fujimoto, R., Yamasaki, N.Y., Mitsuda, K.
    Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 559(2), 2006  
  • Fujimoto, R., Mitsuda, K., Hirabayashi, M., Narasaki, K., Breon, S., Boyle, R., DiPirro, M., Volz, S.M., Kelley, R.L.
    Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 559(2), 2006  
  • Ota, N., Inada, N., Oguri, M., Mitsuda, K., Richards, G.T., Suto, Y., Brandt, W.N., Castander, F.J., Fujimoto, R., Hall, P.B., Keeton, C.R., Nichol, R.C., Schneider, D.P., Eisenstein, D.E., Frieman, J.A., Turner, E.L., Minezaki, T., Yoshi, Y.
    Astrophysical Journal, 647(1 I) 215-221, 2006  
    We present results from Chandra observations of SDSS J1004+4112, a strongly lensed quasar system with a maximum image separation of 15''. All four bright images of the quasar, as well as resolved X-ray emission originating from the lensing cluster, are clearly detected. The emission from the lensing cluster extends out to approximately 1'5. We measure the bolometric X-ray luminosity and temperature of the lensing cluster to be 4.7; 10(44) ergs s(-1) and 6.4 keV, consistent with the luminosity-temperature relation for distant clusters. The mass estimated from the X-ray observation shows excellent agreement with the mass derived from gravitational lensing. The X-ray flux ratios of the quasar images differ markedly from the optical flux ratios, and the combined X-ray spectrum of the images possesses an unusually strong Fe K alpha emission line, both of which are indicative of microlensing.
  • Kilbourne, C.A., Boyce, K.R., Brown, G.V., Cottam, J., Figueroa-Feliciano, E., Fujimoto, R., Furusho, T., Ishisaki, Y., Kelley, R.L., McCammon, D., Mitsuda, K., Morita, U., Porter, F.S., Ota, N., Saab, T., Takei, Y., Yamamoto, M.
    Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 559(2), 2006  
  • Cottam, J., Boyce, K.R., Brown, G.V., Fujimoto, R., Furusho, T., Ishisaki, Y., Kelley, R.L., Kilbourne, C.A., McCammon, D., Mitsuda, K., Morita, U., Ota, N., Porter, F.S., Saab, T., Takei, Y., Yamamoto, M.
    Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 559(2), 2006  
  • Ota, N., Boyce, K.R., Brown, G.V., Cottam, J., Fujimoto, R., Furusho, T., Ishisaki, Y., Kelley, R.L., Kilbourne, C.A., McCammon, D., Mitsuda, K., Morita, U., Porter, F.S., Takei, Y., Yamamoto, M.
    Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 559(2), 2006  
  • Morita, U., Yamakawa, Y., Fujimori, T., Ishisaki, Y., Ohashi, T., Takei, Y., Yoshida, K., Yoshino, T., Mitsuda, K., Yamasaki, N.Y., Fujimoto, R., Sato, H., Minoura, Y., Takahashi, N., Homma, T., Shoji, S., Kuroda, Y., Onishi, M.
    Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 559(2), 2006  
  • A Hayakawa, C Inoue, Y Ishisaki, M Ishida, T Ohashi, T Furusho, NY Yamasaki, R Fujimoto, K Mitsuda, K Misaki, Y Maeda, H Kunieda
    OPTICS FOR EUV, X-RAY AND GAMMA-RAY ASTRONOMY, 5168 364-375, 2004  Peer-reviewed
    X-Ray Spectrometer (XRS) is the microcalorimeter onboard the X-ray astronomy satellite Astro-E2 which is scheduled to be launched early in 2005. For the XRS to achieve its best energy resolution of 6 eV at 6 keV, X-ray intensity should be limited up to several c s(-1) pixel(-1). The filter wheel (FW) is the instrument to reduce incident X-ray intensity on the XRS using extinction filters. The FW consists of a stepping motor, extinction filters, and a filter disk which has six mounting positions for the extinction filters. Among the six mounting points, two are used for Neutral Density (ND) filters, another two are for Beryllium (Be) filters, and the other two are remained open. The biggest modification from Astro-E is that we attach radioisotopes of Fe-55 and Ca-41 on the filter disk, which illuminate the XRS pixels to monitor the gain in orbit. We present here the mechanical design of the FW especially on improvements from Astro-E, and the results of our calibration measurements on X-ray transmission of the extinction filters.
  • Y Ishisaki, T Ohashi, T Oshima, U Morita, K Shinozaki, K Sato, K Mitsuda, NY Yamasaki, R Fujimoto, Y Takei, H Sato, N Takahashi, T Homma, T Osaka
    HIGH-ENERGY DETECTORS IN ASTRONOMY, 5501 123-134, 2004  
    We are developing a superconducting transition-edge sensor (TES) microcalorimeter array for the Diffuse Intergalactic Oxygen Surveyor (DIOS) mission. DIOS is a relatively small Japanese X-ray mission which will study large-scale distribution of the warm-hot intergalactic medium (WHIM) using O-VII and O-VIII emission lines. The satellite weighs about 400 kg equipped with a four-reflection X-ray telescope (FXT) and a TES microcalorimeter array (XSA). The design goal of the observing system is an effective area larger than 100 cm 2 at the oxygen line energy, a field of view about 50 arcmin square, and an energy resolution about 2 eV in the energy range of 0.3-1 keV. The TES microcalorimeter array provides the large field of view and good energy resolution at the same time. We plan to install an array comprising 16 x 16 pixels with an overall size of 1 cm square, which is cooled with a cryogen-free cooler. Pixels are readout by multiplexing signals using a multi-input SQUID amplifier, with each input connected to a TES microcalorimeter which is AC biased with a different frequency. We report the design and present status of the XSA system development.
  • Kudo, H., Nakamura, T., Arakawa, T., Ohtsuka, S., Izumi, T., Shoji, S., Sato, S., Kobayashi, H., Mori, K., Homma, T., Osaka, T., Mitsuda, K., Yamasaki, N.Y., Fujimoto, R., Iyomoto, N., Oshima, T., Futamoto, K., Takei, Y., Ichitsubo, T., Fujimori, T., Ishisaki, Y., Morita, U., Koga, T., Sato, K., Ohashi, T., Kuroda, Y., Onishi, M., Otake, K., Beppu, F.
    Sensors and Actuators, A: Physical, 114(2-3), 2004  

Misc.

 129
  • 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, Aug 20, 2018  
  • Alle, S.W., Aharonian, F., Akamatsu, H., Akimoto, F., Allen, S.W., Angelini, L., Audard, M., Awaki, H., Axelsson, M., Bamba, A., Bautz, M.W., Blandford, R., Brenneman, L.W., Brown, G.V., Bulbul, E., Cackett, E.M., Chernyakova, M., Chiao, M.P., Coppi, P.S., Costantini, E., De Plaa, J., De Vries, C.P., Den Herder, J.-W., Done, C., Dotani, T., Ebisawa, K., Eckart, M.E., Enoto, T., Ezoe, Y., Fabian, A.C., Ferrigno, C., Foster, A.R., Fujimoto, R., Fukazawa, Y., Furuzawa, A., Galeazzi, M., Gallo, L.C., Gandhi, P., Giustini, M., Goldwurm, A., Gu, L., Guainazzi, M., Haba, Y., Hagino, K., Hamaguchi, K., Harrus, I.M., Hatsukade, I., Hayashi, K., Hayashi, T., Hayashida, K., Hiraga, J.S., Hornschemeier, A., Hoshino, A., Hughes, J.P., Ichinohe, Y., Iizuka, R., Inoue, H., Inoue, Y., Ishida, M., Ishikawa, K., Ishisaki, Y., Iwai, M., Kaastra, J., Kallman, T., Kamae, T., Kataoka, J., Katsuda, S., Kawai, N., Kelley, R.L., Kilbourne, C.A., Kitaguchi, T., Kitamoto, S., Kitayama, T., Kohmura, T., Kokubun, M., Koyama, K., Koyama, S., Kretschmar, P., Krimm, H.A., Kubota, A., Kunieda, H., Laurent, P., Lee, S.-H., Leutenegger, M.A., Limousin, O.O., Loewenstein, M., Long, K.S., Lumb, D., Madejski, G., Maeda, Y., Maier, D., Makishima, K., Markevitch, M., Matsumoto, H., Matsushita, K., Mccammon, D., Mcnamara, B.R., Mehdipour, M., Miller, E.D., Miller, J.M., Mineshige, S., Mitsuda, K., Mitsuishi, I., Miyazawa, T., Mizuno, T., Mori, H., Mori, K., Mukai, K., Murakami, H., Mushotzky, R.F., Nakagawa, T., Nakajima, H., Nakamori, T., Nakashima, S., Nakazawa, K., Nobukawa, K.K., Nobukawa, M., Noda, H., Odaka, H., Ohashi, T., Ohno, M., Okajima, T., Ota, N., Ozaki, M., Paerels, F., Paltani, S., Petre, R., Pinto, C., Porter, F.S., Pottschmidt, K., Reynolds, C.S., Safi-Harb, S., Saito, S., Sakai, K., Sasaki, T., Sato, G., Sato, K., Sato, R., Sawada, M., Schartel, N., Serlemtsos, P.J., Seta, H., Shidatsu, M., Simionescu, A., Smith, R.K., Soong, Y., Stawarz, Ł., Sugawara, Y., Sugita, S., Szymkowiak, A., Tajima, H., Takahashi, H., Takahashi, T., Takeda, S., Takei, Y., Tamagawa, T., Tamura, T., Tanaka, T., Tanaka, Y., Tanaka, Y.T., Tashiro, M.S., Tawara, Y., Terada, Y., Terashima, Y., Tombesi, F., Tomida, H., Tsuboi, Y., Tsujimoto, M., Tsunemi, H., Suru, T.G., Uchida, H., Uchiyama, H., Uchiyama, Y., Ueda, S., Ueda, Y., Uno, S., Urry, C.M., Ursino, E., Watanabe, S., Werner, N., Wilkins, D.R., Williams, B.J., Yamada, S., Yamaguchi, H., Yamaoka, K., Yamasaki, N.Y., Yamauchi, M., Yamauchi, S., Yaqoob, T., Yatsu, Y., Yonetoku, D., Zhuravleva, I., Zoghbi, A., Nakaniwa, N.
    Publications of the Astronomical Society of Japan, 70(2), 2018  
    We report a Hitomi observation of IGR J16318-4848, a high-mass X-ray binary<br /> system with an extremely strong absorption of N_H~10^{24} cm^{-2}. Previous<br /> X-ray studies revealed that its spectrum is dominated by strong fluorescence<br /> lines of Fe as well as continuum emission. For physical and geometrical insight<br /> into the nature of the reprocessing material, we utilize the high spectroscopic<br /> resolving power of the X-ray microcalorimeter (the soft X-ray spectrometer;<br /> SXS) and the wide-band sensitivity by the soft and hard X-ray imager (SXI and<br /> HXI) aboard Hitomi. Even though photon counts are limited due to unintended<br /> off-axis pointing, the SXS spectrum resolves Fe K{\alpha_1} and K{\alpha_2}<br /> lines and puts strong constraints on the line centroid and width. The line<br /> width corresponds to the velocity of 160^{+300}_{-70} km s^{-1}. This<br /> represents the most accurate, and smallest, width measurement of this line made<br /> so far from any X-ray binary, much less than the Doppler broadening and shift<br /> expected from speeds which are characteristic of similar systems. Combined with<br /> the K-shell edge energy measured by the SXI and HXI spectra, the ionization<br /> state of Fe is estimated to be in the range of Fe I--IV. Considering the<br /> estimated ionization parameter and the distance between the X-ray source and<br /> the absorber, the density and thickness of the materials are estimated. The<br /> extraordinarily strong absorption and the absence of a Compton shoulder<br /> component is confirmed. These characteristics suggest reprocessing materials<br /> which are distributed in a narrow solid angle or scattering primarily with warm<br /> free electrons or neutral hydrogen.
  • Aharonian, F., Akamatsu, H., Akimoto, F., Allen, S.W., Angelini, L., Audard, M., Awaki, H., Axelsson, M., Bamba, A., Bautz, M.W., Blandford, R., Brenneman, L.W., Brown, G.V., Bulbul, E., Cackett, E.M., Chernyakova, M., Chiao, M.P., Coppi, P.S., Costantini, E., De Plaa, J., De Vries, C.P., Den Herder, J.-W., Done, C., Dotani, T., Ebisawa, K., Eckart, M.E., Enoto, T., Ezoe, Y., Fabian, A.C., Ferrigno, C., Foster, A.R., Fujimoto, R., Fukazawa, Y., Furuzawa, A., Galeazzi, M., Gallo, L.C., Gandhi, P., Giustini, M., Goldwurm, A., Gu, L., Guainazzi, M., Haba, Y., Hagino, K., Hamaguchi, K., Harrus, I.M., Hatsukade, I., Hayashi, K., Hayashi, T., Hayashida, K., Hiraga, J.S., Hornschemeier, A., Hoshino, A., Hughes, J.P., Ichinohe, Y., Iizuka, R., Inoue, H., Inoue, Y., Ishida, M., Ishikawa, K., Ishisaki, Y., Iwai, M., Kaastra, J., Kallman, T., Kamae, T., Kataoka, J., Katsuda, S., Kawai, N., Kelley, R.L., Kilbourne, C.A., Kitaguchi, T., Kitamoto, S., Kitayama, T., Kohmura, T., Kokubun, M., Koyama, K., Koyama, S., Kretschmar, P., Krimm, H.A., Kubota, A., Kunieda, H., Laurent, P., Lee, S.-H., Leutenegger, M.A., Limousin, O., Loewenstein, M., Long, K.S., Lumb, D., Madejski, G., Maeda, Y., Maier, D., Makishima, K., Markevitch, M., Matsumoto, H., Matsushita, K., McCammon, D., McNamara, B.R., Mehdipour, M., Miller, E.D., Miller, J.M., Mineshige, S., Mitsuda, K., Mitsuishi, I., Miyazawa, T., Mizuno, T., Mori, H., Mori, K., Mukai, K., Murakami, H., Mushotzky, R.F., Nakagawa, T., Nakajima, H., Nakamori, T., Nakashima, S., Nakazawa, K., Nobukawa, K.K., Nobukawa, M., Noda, H., Odaka, H., Ohashi, T., Ohno, M., Okajima, T., Ota, N., Ozaki, M., Paerels, F., Paltani, S., Petre, R., Pinto, C., Porter, F.S., Pottschmidt, K., Reynolds, C.S., Safi-Harb, S., Saito, S., Sakai, K., Sasaki, T., Sato, G., Sato, K., Sato, R., Sawada, M., Schartel, N., Serlemtsos, P.J., Seta, H., Shidatsu, M., Simionescu, A., Smith, R.K., Soong, Y., Stawarz, L., Sugawara, Y., Sugita, S., Szymkowiak, A., Tajima, H., Takahashi, H., Takahashi, T., Takeda, S., Takei, Y., Tamagawa, T., Tamura, T., Tanaka, T., Tanaka, Y., Tanaka, Y.T., Tashiro, M.S., Tawara, Y., Terada, Y., Terashima, Y., Tombesi, F., Tomida, H., Tsuboi, Y., Tsujimoto, M., Tsunemi, H., Tsuru, T.G., Uchida, H., Uchiyama, H., Uchiyama, Y., Ueda, S., Ueda, Y., Uno, S., Urry, C.M., Ursino, E., Watanabe, S., Werner, N., Wilkins, D.R., Williams, B.J., Yamada, S., Yamaguchi, H., Yamaoka, K., Yamasaki, N.Y., Yamauchi, M., Yamauchi, S., Yaqoob, T., Yatsu, Y., Yonetoku, D., Zhuravleva, I., Zoghbi, A., Uchida, Y.
    Publications of the Astronomical Society of Japan, 70(6), 2018  
    We present the results from the Hitomi Soft Gamma-ray Detector (SGD)<br /> observation of the Crab nebula. The main part of SGD is a Compton camera, which<br /> in addition to being a spectrometer, is capable of measuring polarization of<br /> gamma-ray photons. The Crab nebula is one of the brightest X-ray / gamma-ray<br /> sources on the sky, and, the only source from which polarized X-ray photons<br /> have been detected. SGD observed the Crab nebula during the initial test<br /> observation phase of Hitomi. We performed the data analysis of the SGD<br /> observation, the SGD background estimation and the SGD Monte Carlo simulations,<br /> and, successfully detected polarized gamma-ray emission from the Crab nebula<br /> with only about 5 ks exposure time. The obtained polarization fraction of the<br /> phase-integrated Crab emission (sum of pulsar and nebula emissions) is (22.1<br /> $\pm$ 10.6)% and, the polarization angle is 110.7$^o$ + 13.2 / $-$13.0$^o$ in<br /> the energy range of 60--160 keV (The errors correspond to the 1 sigma<br /> deviation). The confidence level of the polarization detection was 99.3%. The<br /> polarization angle measured by SGD is about one sigma deviation with the<br /> projected spin axis of the pulsar, 124.0$^o$ $\pm$0.1$^o$.
  • Aharonian, F., Akamatsu, H., Akimoto, F., Allen, S.W., Angelini, L., Audard, M., Awaki, H., Axelsson, M., Bamba, A., Bautz, M.W., Blandford, R., Brenneman, L.W., Brown, G.V., Bulbul, E., Cackett, E.M., Chernyakova, M., Chiao, M.P., Coppi, P.S., Costantini, E., De Plaa, J., De Vries, C.P., Den Herder, J.-W., Done, C., Dotani, T., Ebisawa, K., Eckart, M.E., Enoto, T., Ezoe, Y., Fabian, A.C., Ferrigno, C., Foster, A.R., Fujimoto, R., Fukazawa, Y., Furukawa, M., Furuzawa, A., Galeazzi, M., Gallo, L.C., Gandhi, P., Giustini, M., Goldwurm, A., Gu, L., Guainazzi, M., Haba, Y., Hagino, K., Hamaguchi, K., Harrus, I.M., Hatsukade, I., Hayashi, K., Hayashi, T., Hayashida, K., Hiraga, J.S., Hornschemeier, A., Hoshino, A., Hughes, J.P., Ichinohe, Y., Iizuka, R., Inoue, H., Inoue, Y., Ishida, M., Ishikawa, K., Ishisaki, Y., Iwai, M., Kaastra, J., Kallman, T., Kamae, T., Kataoka, J., Kato, Y., Katsuda, S., Kawai, N., Kelley, R.L., Kilbourne, C.A., Kitaguchi, T., Kitamoto, S., Kitayama, T., Kohmura, T., Kokubun, M., Koyama, K., Koyama, S., Kretschmar, P., Krimm, H.A., Kubota, A., Kunieda, H., Laurent, P., Lee, S.-H., Leutenegger, M.A., Limousin, O., Loewenstein, M., Long, K.S., Lumb, D., Madejski, G., Maeda, Y., Maier, D., Makishima, K., Markevitch, M., Matsumoto, H., Matsushita, K., McCammon, D., McNamara, B.R., Mehdipour, M., Miller, E.D., Miller, J.M., Mineshige, S., Mitsuda, K., Mitsuishi, I., Miyazawa, T., Mizuno, T., Mori, H., Mori, K., Mukai, K., Murakami, H., Mushotzky, R.F., Nakagawa, T., Nakajima, H., Nakamori, T., Nakashima, S., Nakazawa, K., Nobukawa, K.K., Nobukawa, M., Noda, H., Odaka, H., Ohashi, T., Ohno, M., Okajima, T., Ota, N., Ozaki, M., Paerels, F., Paltani, S., Petre, R., Pinto, C., Porter, F.S., Pottschmidt, K., Reynolds, C.S., Safi-Harb, S., Saito, S., Sakai, K., Sasaki, T., Sato, G., Sato, K., Sato, R., Sawada, M., Schartel, N., Serlemtsos, P.J., Seta, H., Shidatsu, M., Simionescu, A., Smith, R.K., Soong, Y., Stawarz, Ł., Sugawara, Y., Sugita, S., Szymkowiak, A., Tajima, H., Takahashi, H., Takahashi, T., Takeda, S., Takei, Y., Tamagawa, T., Tamura, T., Tanaka, T., Tanaka, Y., Tanaka, Y.T., Tashiro, M.S., Tawara, Y., Terada, Y., Terashima, Y., Tombesi, F., Tomida, H., Tsuboi, Y., Tsujimoto, M., Tsunemi, H., Tsuru, T.G., Uchida, H., Uchiyama, H., Uchiyama, Y., Ueda, S., Ueda, Y., Uno, S., Urry, C.M., Ursino, E., Watanabe, S., Werner, N., Wilkins, D.R., Williams, B.J., Yamada, S., Yamaguchi, H., Yamaoka, K., Yamasaki, N.Y., Yamauchi, M., Yamauchi, S., Yaqoob, T., Yatsu, Y., Yonetoku, D., Zhuravleva, I., Zoghbi, A.
    Publications of the Astronomical Society of Japan, 70(2), 2018  
    The present paper investigates the temperature structure of the X-ray<br /> emitting plasma in the core of the Perseus cluster using the 1.8--20.0 keV data<br /> obtained with the Soft X-ray Spectrometer (SXS) onboard the Hitomi Observatory.<br /> A series of four observations were carried out, with a total effective exposure<br /> time of 338 ks and covering a central region $\sim7&#039;$ in diameter. The SXS was<br /> operated with an energy resolution of $\sim$5 eV (full width at half maximum)<br /> at 5.9 keV. Not only fine structures of K-shell lines in He-like ions but also<br /> transitions from higher principal quantum numbers are clearly resolved from Si<br /> through Fe. This enables us to perform temperature diagnostics using the line<br /> ratios of Si, S, Ar, Ca, and Fe, and to provide the first direct measurement of<br /> the excitation temperature and ionization temperature in the Perseus cluster.<br /> The observed spectrum is roughly reproduced by a single temperature thermal<br /> plasma model in collisional ionization equilibrium, but detailed line ratio<br /> diagnostics reveal slight deviations from this approximation. In particular,<br /> the data exhibit an apparent trend of increasing ionization temperature with<br /> increasing atomic mass, as well as small differences between the ionization and<br /> excitation temperatures for Fe, the only element for which both temperatures<br /> can be measured. The best-fit two-temperature models suggest a combination of 3<br /> and 5 keV gas, which is consistent with the idea that the observed small<br /> deviations from a single temperature approximation are due to the effects of<br /> projection of the known radial temperature gradient in the cluster core along<br /> the line of sight. Comparison with the Chandra/ACIS and the XMM-Newton/RGS<br /> results on the other hand suggests that additional lower-temperature components<br /> are present in the ICM but not detectable by Hitomi SXS given its 1.8--20 keV<br /> energy band.
  • Aharonian, F., Akamatsu, H., Akimoto, F., Allen, S.W., Angelini, L., Audard, M., Awaki, H., Axelsson, M., Bamba, A., Bautz, M.W., Blandford, R., Brenneman, L.W., Brown, G.V., Bulbul, E., Cackett, E.M., Chernyakova, M., Chiao, M.P., Coppi, P.S., Costantini, E., De Plaa, J., De Vries, C.P., Den Herder, J.-W., Done, C., Dotani, T., Ebisawa, K., Eckart, M.E., Enoto, T., Ezoe, Y., Fabian, A.C., Ferrigno, C., Foster, A.R., Fujimoto, R., Fukazawa, Y., Furuzawa, A., Galeazzi, M., Gallo, L.C., Gandhi, P., Giustini, M., Goldwurm, A., Gu, L., Guainazzi, M., Haba, Y., Hagino, K., Hamaguchi, K., Harrus, I.M., Hatsukade, I., Hayashi, K., Hayashi, T., Hayashida, K., Hell, N., Hiraga, J.S., Hornschemeier, A., Hoshino, A., Hughes, J.P., Ichinohe, Y., Iizuka, R., Inoue, H., Inoue, Y., Ishida, M., Ishikawa, K., Ishisaki, Y., Iwai, M., Kaastra, J., Kallman, T., Kamae, T., Kataoka, J., Katsuda, S., Kawai, N., Kelley, R.L., Kilbourne, C.A., Kitaguchi, T., Kitamoto, S., Kitayama, T., Kohmura, T., Kokubun, M., Koyama, K., Koyama, S., Kretschmar, P., Krimm, H.A., Kubota, A., Kunieda, H., Laurent, P., Lee, S.-H., Leutenegger, M.A., Limousin, O., Loewenstein, M., Long, K.S., Lumb, D., Madejski, G., Maeda, Y., Maier, D., Makishima, K., Markevitch, M., Matsumoto, H., Matsushita, K., McCammon, D., McNamara, B.R., Mehdipour, M., Miller, E.D., Miller, J.M., Mineshige, S., Mitsuda, K., Mitsuishi, I., Miyazawa, T., Mizuno, T., Mori, H., Mori, K., Mukai, K., Murakami, H., Mushotzky, R.F., Nakagawa, T., Nakajima, H., Nakamori, T., Nakashima, S., Nakazawa, K., Nobukawa, K.K., Nobukawa, M., Noda, H., Odaka, H., Ohashi, T., Ohno, M., Okajima, T., Ota, N., Ozaki, M., Paerels, F., Paltani, S., Petre, R., Pinto, C., Porter, F.S., Pottschmidt, K., Reynolds, C.S., Safi-Harb, S., Saito, S., Sakai, K., Sasaki, T., Sato, G., Sato, K., Sato, R., Sawada, M., Schartel, N., Serlemtsos, P.J., Seta, H., Shidatsu, M., Simionescu, A., Smith, R.K., Soong, Y., Stawarz, Ł., Sugawara, Y., Sugita, S., Szymkowiak, A., Tajima, H., Takahashi, H., Takahashi, T., Takeda, S., Takei, Y., Tamagawa, T., Tamura, T., Tanaka, T., Tanaka, Y., Tanaka, Y.T., Tashiro, M.S., Tawara, Y., Terada, Y., Terashima, Y., Tombesi, F., Tomida, H., Tsuboi, Y., Tsujimoto, M., Tsunemi, H., Tsuru, T.G., Uchida, H., Uchiyama, H., Uchiyama, Y., Ueda, S., Ueda, Y., Uno, S., Urry, C.M., Ursino, E., Watanabe, S., Werner, N., Wilkins, D.R., Williams, B.J., Yamada, S., Yamaguchi, H., Yamaoka, K., Yamasaki, N.Y., Yamauchi, M., Yamauchi, S., Yaqoob, T., Yatsu, Y., Yonetoku, D., Zhuravleva, I., Zoghbi, A., Raassen, A.J.J.
    Publications of the Astronomical Society of Japan, 70(2), 2018  
    The Hitomi SXS spectrum of the Perseus cluster, with $\sim$5 eV resolution in<br /> the 2-9 keV band, offers an unprecedented benchmark of the atomic modeling and<br /> database for hot collisional plasmas. It reveals both successes and challenges<br /> of the current atomic codes. The latest versions of AtomDB/APEC (3.0.8), SPEX<br /> (3.03.00), and CHIANTI (8.0) all provide reasonable fits to the broad-band<br /> spectrum, and are in close agreement on best-fit temperature, emission measure,<br /> and abundances of a few elements such as Ni. For the Fe abundance, the APEC and<br /> SPEX measurements differ by 16%, which is 17 times higher than the statistical<br /> uncertainty. This is mostly attributed to the differences in adopted<br /> collisional excitation and dielectronic recombination rates of the strongest<br /> emission lines. We further investigate and compare the sensitivity of the<br /> derived physical parameters to the astrophysical source modeling and<br /> instrumental effects. The Hitomi results show that an accurate atomic code is<br /> as important as the astrophysical modeling and instrumental calibration<br /> aspects. Substantial updates of atomic databases and targeted laboratory<br /> measurements are needed to get the current codes ready for the data from the<br /> next Hitomi-level mission.
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