Proton Radiation Damage Experiment for X-Ray SOI Pixel Detectors

Keigo Yarita; Takayoshi Kohmura; Kouichi Hagino; Taku Kogiso; Kenji Oono; Kousuke Negishi; Koki Tamasawa; Akinori Sasaki; Satoshi Yoshiki; Takeshi Go Tsuru; Takaaki Tanaka; Hideaki Matsumura; Katsuhiro Tachibana; Hideki Hayashi; Sodai Harada; Ayaki Takeda; Koji Mori; Yusuke Nishioka; Nobuaki Takebayashi; Shoma Yokoyama; Kohei Fukuda; Yasuo Arai; Toshinobu Miyoshi; Ikuo Kurachi; Tsuyoshi Hamano; the SOIPIX group

doi:10.1016/j.nima.2018.09.057

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arXiv · 1810.09193

Proton Radiation Damage Experiment for X-Ray SOI Pixel Detectors

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Abstract

In low earth orbit, there are many cosmic rays composed primarily of high energy protons. These cosmic rays cause surface and bulk radiation effects, resulting in degradation of detector performance. Quantitative evaluation of radiation hardness is essential in development of X-ray detectors for astronomical satellites. We performed proton irradiation experiments on newly developed X-ray detectors called XRPIX based on silicon-on-insulator technology at HIMAC in National Institute of Radiological Sciences. We irradiated 6 MeV protons with a total dose of 0.5 krad, equivalent to 6 years irradiation in orbit. As a result, the gain increases by 0.2% and the energy resolution degrades by 0.5%. Finally we irradiated protons up to 20 krad and found that detector performance degraded significantly at 5 krad. With 5 krad irradiation corresponding to 60 years in orbit, the gain increases by 0.7% and the energy resolution worsens by 10%. By decomposing into noise components, we found that the increase of the circuit noise is dominant in the degradation of the energy resolution.

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Keigo Yarita, Takayoshi Kohmura, Kouichi Hagino, Taku Kogiso, Kenji Oono, Kousuke Negishi, Koki Tamasawa, Akinori Sasaki, Satoshi Yoshiki, Takeshi Go Tsuru, Takaaki Tanaka, Hideaki Matsumura, Katsuhiro Tachibana, Hideki Hayashi, Sodai Harada, Ayaki Takeda, Koji Mori, Yusuke Nishioka, Nobuaki Takebayashi, Shoma Yokoyama, Kohei Fukuda, Yasuo Arai, Toshinobu Miyoshi, Ikuo Kurachi, Tsuyoshi Hamano, the SOIPIX group. 2018-10-22. Proton Radiation Damage Experiment for X-Ray SOI Pixel Detectors. https://doi.org/10.1016/j.nima.2018.09.057

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