Optical Blocking Performance of CCDs Developed for the X-ray Astronomy Satellite XRISM

Hiroyuki Uchida; Takaaki Tanaka; Yuki Amano; Hiromichi Okon; Takeshi G. Tsuru; Hirofumi Noda; Kiyoshi Hayashida; Hironori Matsumoto; Maho Hanaoka; Tomokage Yoneyama; Koki Okazaki; Kazunori Asakura; Shotaro Sakuma; Kengo Hattori; Ayami Ishikura; Hiroshi Nakajima; Mariko Saito; Kumiko K. Nobukawa; Hiroshi Tomida; Yoshiaki Kanemaru; Jin Sato; Toshiyuki Takaki; Yuta Terada; Koji Mori; Hikari Kashimura; Takayoshi Kohmura; Kouichi Hagino; Hiroshi Murakami; Shogo B. Kobayashi; Yusuke Nishioka; Makoto Yamauchi; Isamu Hatsukade; Takashi Sako; Masayoshi Nobukawa; Yukino Urabe; Junko S. Hiraga; Hideki Uchiyama; Kazutaka Yamaoka; Masanobu Ozaki; Tadayasu Dotani; Hiroshi Tsunemi; Hisanori Suzuki; Shin-ichiro Takagi; Kenichi Sugimoto; Sho Atsumi; Fumiya Tanaka

doi:10.1016/j.nima.2020.164374

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arXiv · 2007.07608

Optical Blocking Performance of CCDs Developed for the X-ray Astronomy Satellite XRISM

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Abstract

We have been developing P-channel Charge-Coupled Devices (CCDs) for the upcoming X-ray Astronomy Satellite XRISM, planned to be launched in 2021. While the basic design of the CCD camera (Soft X-ray Imager: SXI) is almost the same as that of the lost Hitomi (ASTRO-H) observatory, we are planning to reduce the "light leakages" that is one of the largest problems recognized in Hitomi data. We adopted a double-layer optical blocking layer on the XRISM CCDs and also added an extra aluminum layer on the backside of them. We develop a newly designed test sample CCD and irradiate it with optical light to evaluate the optical blocking performance. As a result, light leakages are effectively reduced compared with that of the Hitomi CCDs. We thus conclude that the issue is solved by the new design and that the XRISM CCDs satisfy the mission requirement for the SXI.

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Hiroyuki Uchida, Takaaki Tanaka, Yuki Amano, Hiromichi Okon, Takeshi G. Tsuru, Hirofumi Noda, Kiyoshi Hayashida, Hironori Matsumoto, Maho Hanaoka, Tomokage Yoneyama, Koki Okazaki, Kazunori Asakura, Shotaro Sakuma, Kengo Hattori, Ayami Ishikura, Hiroshi Nakajima, Mariko Saito, Kumiko K. Nobukawa, Hiroshi Tomida, Yoshiaki Kanemaru, Jin Sato, Toshiyuki Takaki, Yuta Terada, Koji Mori, Hikari Kashimura, Takayoshi Kohmura, Kouichi Hagino, Hiroshi Murakami, Shogo B. Kobayashi, Yusuke Nishioka, Makoto Yamauchi, Isamu Hatsukade, Takashi Sako, Masayoshi Nobukawa, Yukino Urabe, Junko S. Hiraga, Hideki Uchiyama, Kazutaka Yamaoka, Masanobu Ozaki, Tadayasu Dotani, Hiroshi Tsunemi, Hisanori Suzuki, Shin-ichiro Takagi, Kenichi Sugimoto, Sho Atsumi, Fumiya Tanaka. 2020-07-16. Optical Blocking Performance of CCDs Developed for the X-ray Astronomy Satellite XRISM. https://doi.org/10.1016/j.nima.2020.164374

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