宇宙物理学研究系

片坐 宏一

カタザ ヒロカズ  (Hirokazu KATAZA)

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

J-GLOBAL ID
202001007925227103
researchmap会員ID
R000009969

論文

 198
  • Takafumi Kamizuka, Hajime Kawahara, Ryou Ohsawa, Hirokazu Kataza, Daisuke Kawata, Yoshiyuki Yamada, Teruyuki Hirano, Kohei Miyakawa, Masataka Aizawa, Masashi Omiya, Taihei Yano, Ryouhei Kano, Takehiko Wada, Wolfgang Loeffler, Michael Biermann, Pau Ramos, Naoki Isobe, Fumihiko Usui, Kohei Hattori, Satoshi Yoshikawa, Takayuki Tatekawa, Hideyuki Izumiura, Akihiko Fukui, Makoto Miyoshi, Daisuke Tatsumi, Naoteru Gouda
    Modeling, Systems Engineering, and Project Management for Astronomy XI 93-93 2024年8月23日  
  • Takafumi Kamizuka, Takashi Miyata, Shigeyuki Sako, Ryou Ohsawa, Kentaro Asano, Atsushi Nishimura, Kengo Tachibana, Tsubasa Michifuji, Hirokazu Iida, Akira C. Naruse, Mizuho Uchiyama, Itsuki Sakon, Takashi Onaka, Hirokazu Kataza, Sunao Hasegawa, Fumihiko Usui, Naruhisa Takato, Noboru Ebizuka, Takuya Hosobata, Tsutomu Aoki, Mamoru Doi, Fumi Egusa, Bunyo Hatsukade, Natsuko Kato, Kotaro Kohno, Masahiro Konishi, Shintaro Koshida, Shuhei Koyama, Takeo Minezaki, Tomoki Morokuma, Kentaro Motohara, Mizuki Numata, Hiroaki Sameshima, Hidenori Takahashi, Yoichi Tamura, Toshihiko Tanabe, Masuo Tanaka, Kosuke Kushibiki, Nuo Chen, Shogo Homan, Yuzuru Yoshii
    Proceedings of SPIE, Ground-based and Airborne Instrumentation for Astronomy IX 12184 2022年8月29日  
    MIMIZUKU is the first-generation mid-infrared instrument for the TAO 6.5-m telescope. It has three internal optical channels to cover a wide wavelength range from 2 to 38 mu m. Of the three channels, the NIR channel is responsible for observations in the shortest wavelength range, shorter than 5.3 mu m. The performance of the NIR channel is evaluated in the laboratory. Through the tests, we confirm the followings: 1) the detector (HAWAII-1RG with 5.3-mu m cutoff) likely achieves similar to 80% quantum efficiency; 2) imaging performance is sufficient to achieve seeing-limit spatial resolution; 3) system efficiencies in imaging modes are 2.4-31%; and 4) the system efficiencies in spectroscopic modes is 5-18%. These results suggest that the optical performance of the NIR channel is achieved as expected from characteristics of the optical components. However, calculations of the background levels and on-sky sensitivity based on these results suggest that neutral density (ND) filters are needed to avoid saturation in L'- and M'-band observations and that the ND filters and the entrance window, made of chemical-vapor-deposition (CVD) diamond, significantly degrade the sensitivity in these bands. This means that the use of different window materials and improvements of the detector readout speed are required to achieve both near-infrared and long-wavelength mid-infrared (>30 mu m) observations.
  • Kunimoto Komatsu, Hirokazu Ishino, Hirokazu Kataza, Kuniaki Konishi, Makoto Kuwata-Gonokami, Nobuhiko Katayama, Shinya Sugiyama, Tomotake Matsumura, Haruyuki Sakurai, Yuki Sakurai, Ryota Takaku, Junji Yumoto
    Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy X 11453 2020年12月18日  
    We have developed a prototype half-wave plate (HWP) based polarization modulator (PMU) for Cosmic Microwave Background polarization measurement experiments. We built a 1/10 scaled PMU that consists of a 50 mm diameter five-layer achromatic HWP with a moth-eye broadband anti-reflection sub-wavelength structure mounted on a superconducting magnetic bearing. The entire system has cooled below 20 K in a cryostat chamber that has two millimeter-wave transparent windows. A coherent source and the diode detector are placed outside of the cryostat and the millimeter-wave goes through the PMU in the cryostat. We have measured the modulated signal by the PMU, analyzed the spectral signatures, and extracted the modulation efficiency over the frequency coverage of 34-161 GHz. We identified the peaks in the optical data, which are synchronous to the rotational frequency. We also identified the peaks that are originated from the resonance frequency of the levitating system. We also recovered the modulation efficiency as a function of the incident electromagnetic frequency and the data agrees to the predicted curves within uncertainties of the input parameters, i.e.The indices of refraction, thickness, and angle alignment. Finally, we discuss the implication of the results when this is applied to the LiteBIRD low-frequency telescope.
  • Hajime Kawahara, Kento Masuda, Takayuki Kotani, Shotaro Tada, Koichi Kataza, Satoshi Ikari, Hiroki Aohama, Takayuki Hosonuma, Wataru Mikuriya, Masahiro Ikoma, Satoshi Kasahara, Shigeyuki Sako, Seiji Sugita, Eri Tatsumi, Kazuo Yoshioka
    Space Telescopes and Instrumentation 2020: Optical, Infrared, and Millimeter Wave 2020年12月13日  
  • Takafumi Kamizuka, Takashi Miyata, Shigeyuki Sako, Ryou Ohsawa, Kentaro Asano, Masahito S. Uchiyama, Tomohiro Mori, Yutaka Yoshida, Kengo Tachibana, Tsubasa Michifuji, Mizuho Uchiyama, Itsuki Sakon, Takashi Onaka, Hirokazu Kataza, Tsutomu Aoki, Mamoru Doi, Bunyo Hatsukade, Natsuko M. Kato, Kotaro Kohno, Masahiro Konishi, Takeo Minezaki, Tomoki Morokuma, Mizuki Numata, Kentaro Motohara, Hiroaki Sameshima, Takao Soyano, Hidenori Takahashi, Toshihiko Tanabe, Masuo Tanaka, Ken'ichi Tarusawa, Shintaro Koshida, Yoichi Tamura, Yasunori Terao, Kosuke Kushibiki, Hiroki Nakamura, Yuzuru Yoshii
    Ground-based and Airborne Instrumentation for Astronomy VIII 2020年12月13日  

MISC

 155

共同研究・競争的資金等の研究課題

 25