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arXiv · 2406.19911

Status of Xtend telescope onboard X-Ray Imaging and Spectroscopy Mission (XRISM)

Abstract

Xtend is one of the two telescopes onboard the X-ray imaging and spectroscopy mission (XRISM), which was launched on September 7th, 2023. Xtend comprises 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. A large field of view of $38^{\prime}\times38^{\prime}$ over the energy range from 0.4 to 13 keV is realized by the combination of the SXI and XMA with a focal length of 5.6 m. The SXI employs four P-channel, back-illuminated type CCDs with a thick depletion layer of 200 $\mu$m. The four CCD chips are arranged in a 2$\times$2 grid and cooled down to $-110$ $^{\circ}$C with a single-stage Stirling cooler. Before the launch of XRISM, we conducted a month-long spacecraft thermal vacuum test. The performance verification of the SXI was successfully carried out in a course of multiple thermal cycles of the spacecraft. About a month after the launch of XRISM, the SXI was carefully activated and the soundness of its functionality was checked by a step-by-step process. Commissioning observations followed the initial operation. We here present pre- and post-launch results verifying the Xtend performance. All the in-orbit performances are consistent with those measured on ground and satisfy the mission requirement. Extensive calibration studies are ongoing.

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Koji Mori, Hiroshi Tomida, Hiroshi Nakajima, Takashi Okajima, Hirofumi Noda, Hiroyuki Uchida, Hiromasa Suzuki, Shogo Benjamin Kobayashi, Tomokage Yoneyama, Kouichi Hagino, Kumiko Nobukawa, Takaaki Tanaka, Hiroshi Murakami, Hideki Uchiyama, Masayoshi Nobukawa, Hironori Matsumoto, Takeshi Tsuru, Makoto Yamauchi, Isamu Hatsukade, Hirokazu Odaka, Takayoshi Kohmura, Kazutaka Yamaoka, Manabu Ishida, Yoshitomo Maeda, Takayuki Hayashi, Keisuke Tamura, Rozenn Boissay-Malaquin, Toshiki Sato, Tessei Yoshida, Yoshiaki Kanemaru, Junko Hiraga, Tadayasu Dotani, Masanobu Ozaki, Hiroshi Tsunemi, Shun Inoue, Ryuishi Azuma, Yuma Aoki, Yoh Asahina, Shotaro Nakamura, Takamitsu Kamei, Masahiro Fukuda, Kazunori Asakura, Marina Yoshimoto, Yuichi Ode, Tomohiro Hakamata, Mio Aoyagi, Kohei shima, Yamato Ito, Daiki Aoki, Kaito Fujisawa, Yasuyuki Shimizu, Mayu Higuchi, Keitaro Miyazaki, Kohei Kusunoki, Yoshinori Otsuka, Haruhiko Yokosu, Wakana Yonemaru, Kazuhiro Ichikawa, Hanako Nakano, Reo takemoto, Tsukasa Matsushima, Kiyoshi Hayashida. 2024-06-28. Status of Xtend telescope onboard X-Ray Imaging and Spectroscopy Mission (XRISM). https://arxiv.org/abs/2406.19911

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