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arXiv · 2303.07575

Xtend, the Soft X-ray Imaging Telescope for the X-ray Imaging and Spectroscopy Mission (XRISM)

Koji Mori·Hiroshi Tomida·Hiroshi Nakajima·Takashi Okajima·Hirofumi Noda·Takaaki Tanaka·Hiroyuki Uchida·Kouichi Hagino·Shogo Benjamin Kobayashi·Hiromasa Suzuki·Tessei Yoshida·Hiroshi Murakami·Hideki Uchiyama·Masayoshi Nobukawa·Kumiko Nobukawa·Tomokage Yoneyama·Hironori Matsumoto·Takeshi Tsuru·Makoto Yamauchi·Isamu Hatsukade·Manabu Ishida·Yoshitomo Maeda·Takayuki Hayashi·Keisuke Tamura·Rozenn Boissay-Malaquin·Toshiki Sato·Junko Hiraga·Takayoshi Kohmura·Kazutaka Yamaoka·Tadayasu Dotani·Masanobu Ozaki·Hiroshi Tsunemi·Yoshiaki Kanemaru·Jin Sato·Toshiyuki Takaki·Yuta Terada·Keitaro Miyazaki·Kohei Kusunoki·Yoshinori Otsuka·Haruhiko Yokosu·Wakana Yonemaru·Yoh Asahina·Kazunori Asakura·Marina Yoshimoto·Yuichi Ode·Junya Sato·Tomohiro Hakamata·Mio Aoyagi·Yuma Aoki·Shun Tsunomachi·Toshiki Doi·Daiki Aoki·Kaito Fujisawa·Masatoshi Kitajima·Kiyoshi Hayashida
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Abstract

Xtend is a soft X-ray imaging telescope developed for the X-Ray Imaging and Spectroscopy Mission (XRISM). XRISM is scheduled to be launched in the Japanese fiscal year 2022. Xtend consists of the Soft X-ray Imager (SXI), an X-ray CCD camera, and the X-ray Mirror Assembly (XMA), a thin-foil-nested conically approximated Wolter-I optics. The SXI uses the P-channel, back-illuminated type CCD with an imaging area size of 31 mm on a side. The four CCD chips are arranged in a 2$\times$2 grid and can be cooled down to $-120$ $^{\circ}$C with a single-stage Stirling cooler. The XMA nests thin aluminum foils coated with gold in a confocal way with an outer diameter of 45~cm. A pre-collimator is installed in front of the X-ray mirror for the reduction of the stray light. Combining the SXI and XMA with a focal length of 5.6m, a field of view of $38^{\prime}\times38^{\prime}$ over the energy range from 0.4 to 13 keV is realized. We have completed the fabrication of the flight model of both SXI and XMA. The performance verification has been successfully conducted in a series of sub-system level tests. We also carried out on-ground calibration measurements and the data analysis is ongoing.

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Koji Mori, Hiroshi Tomida, Hiroshi Nakajima, Takashi Okajima, Hirofumi Noda, Takaaki Tanaka, Hiroyuki Uchida, Kouichi Hagino, Shogo Benjamin Kobayashi, Hiromasa Suzuki, Tessei Yoshida, Hiroshi Murakami, Hideki Uchiyama, Masayoshi Nobukawa, Kumiko Nobukawa, Tomokage Yoneyama, Hironori Matsumoto, Takeshi Tsuru, Makoto Yamauchi, Isamu Hatsukade, Manabu Ishida, Yoshitomo Maeda, Takayuki Hayashi, Keisuke Tamura, Rozenn Boissay-Malaquin, Toshiki Sato, Junko Hiraga, Takayoshi Kohmura, Kazutaka Yamaoka, Tadayasu Dotani, Masanobu Ozaki, Hiroshi Tsunemi, Yoshiaki Kanemaru, Jin Sato, Toshiyuki Takaki, Yuta Terada, Keitaro Miyazaki, Kohei Kusunoki, Yoshinori Otsuka, Haruhiko Yokosu, Wakana Yonemaru, Yoh Asahina, Kazunori Asakura, Marina Yoshimoto, Yuichi Ode, Junya Sato, Tomohiro Hakamata, Mio Aoyagi, Yuma Aoki, Shun Tsunomachi, Toshiki Doi, Daiki Aoki, Kaito Fujisawa, Masatoshi Kitajima, Kiyoshi Hayashida. 2023-03-14. Xtend, the Soft X-ray Imaging Telescope for the X-ray Imaging and Spectroscopy Mission (XRISM). https://doi.org/10.1117/12.2626894

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