日本地球惑星科学連合2018年大会

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セッション記号 P (宇宙惑星科学) » P-EM 太陽地球系科学・宇宙電磁気学・宇宙環境

[P-EM16] Dynamics of Earth's Inner Magnetosphere and Initial Results from Arase

2018年5月22日(火) 10:45 〜 12:15 303 (幕張メッセ国際会議場 3F)

コンビーナ:Danny Summers(Memorial University of Newfoundland)、三好 由純(名古屋大学宇宙地球環境研究所)、細川 敬祐(電気通信大学大学院情報理工学研究科、共同)、海老原 祐輔(京都大学生存圏研究所)、座長:細川 敬祐(電気通信大学)

11:30 〜 11:45

[PEM16-28] Spatial distribution of radiation belt protons deduced from solar cell degradation of the Arase satellite

*戸田 穂乃香1三宅 亙1三好 由純2豊田 裕之3宮沢 優3篠原 育3松岡 彩子3 (1.東海大学、2.名古屋大学宇宙地球環境研究所、3.JAXA宇宙科学研究所)

キーワード:あらせ衛星、プロトン放射線帯、太陽電池劣化

Solar cells mounted on any satellites are susceptible to effect of abundant space radiations. Solar cells on the Arase satellite orbiting in the inner magnetosphere degrade due to trapped protons with energies of more than 6 MeV. In the current study, we try to deduce spatial distribution of the radiation belt protons from analysis of output variation of the SAP (Solar-cell Array Panel) of the Arase satellite.

Analysis of the SAP data from launch (20 December, 2016) to 2017 year-end showed a clear degradation that could be attributed to trapped protons. Radiation dosage was determined from Voc (Open circuit voltage) variation of the solar cells and we made comparison with those expected from various distribution models (AP8MAX, AP9MEAN and CRRESPRO quiet) of trapped protons. We found a general agreement with degradation expected from the distribution models, which demonstrates that the trapped protons are major cause of the degradation. However, there remains a little difference in expected radiation dosage from the model calculations. The Voc is also sensitive to temperature. We modify the models, including temperature variation, to minimize the difference and discuss the spatial distribution of trapped MeV protons.