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arXiv · 1306.5400

Proton Radiation Damage Experiment on P-Channel CCD for an X-ray CCD camera onboard the Astro-H satellite

Koji Mori·Yusuke Nishioka·Satoshi Ohura·Yoshiaki Koura·Makoto Yamauchi·Hiroshi Nakajima·Shutaro Ueda·Hiroaki Kan·Naohisa Anabuki·Ryo Nagino·Kiyoshi Hayashida·Hiroshi Tsunemi·Takayoshi Kohmura·Shoma Ikeda·Hiroshi Murakami·Masanobu Ozaki·Tadayasu Dotani·Yukie Maeda·Kenshi Sagara
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Abstract

We report on a proton radiation damage experiment on P-channel CCD newly developed for an X-ray CCD camera onboard the Astro-H satellite. The device was exposed up to 10^9 protons cm^{-2} at 6.7 MeV. The charge transfer inefficiency (CTI) was measured as a function of radiation dose. In comparison with the CTI currently measured in the CCD camera onboard the Suzaku satellite for 6 years, we confirmed that the new type of P-channel CCD is radiation tolerant enough for space use. We also confirmed that a charge-injection technique and lowering the operating temperature efficiently work to reduce the CTI for our device. A comparison with other P-channel CCD experiments is also discussed.

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Koji Mori, Yusuke Nishioka, Satoshi Ohura, Yoshiaki Koura, Makoto Yamauchi, Hiroshi Nakajima, Shutaro Ueda, Hiroaki Kan, Naohisa Anabuki, Ryo Nagino, Kiyoshi Hayashida, Hiroshi Tsunemi, Takayoshi Kohmura, Shoma Ikeda, Hiroshi Murakami, Masanobu Ozaki, Tadayasu Dotani, Yukie Maeda, Kenshi Sagara. 2013-06-23. Proton Radiation Damage Experiment on P-Channel CCD for an X-ray CCD camera onboard the Astro-H satellite. https://doi.org/10.1016/j.nima.2013.05.052

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