タイトル（掲載誌）JAXA Research and Development Report
一般注記In-situ chemical analysis has provided fundamental information on the origin and history of planetary bodies. On rocky bodies, laser-induced breakdown spectroscopy (LIBS) has proven its utility over the last decade. LIBS enables quantitative chemical measurement of samples by analyzing emission spectra from laser-induced plasma. We are currently developing a compact LIBS instrument for future landing missions; however, optical glass experiences degradation in transmittance owing to radiation (the browning effect). We conducted gamma-ray radiation experiments using a Co-60 source to assess radiation-induced transmittance changes in four optical glass materials (Ohara S-LAM3, S-NBH53V, S-TIM27, and S-TIH53W), including those incorporated in the spectrometer we are developing. We applied irradiation doses of 10–10,000 Gy (1–1,000 krad), which are comparable to 0.5–500 years in Martian orbit. Post-irradiation transmission was measured to evaluate the timescale of the recovery in transmittance. Our results indicate that transmittance across wavelengths of 380–1,000 nm decreases in all tested glass materials, with more pronounced decreases at higher doses and shorter wavelengths. Transmittance levels recovered over time, reaching > 95% of their initial values on 365 days after exposure to a 100 Gy dose. The estimated recovery timescales for the materials were 60–130 days. When subjected to a 100 Gy dose, the overall transmission of our spectrometer remained at > 80% of its original, unirradiated value. This suggests that the glass materials used in our LIBS spectrometer are sufficiently resistant to radiation for planetary exploration missions. This study provides crucial data on the radiation resistance of these glasses, aiding the design of optical instruments intended for use in space exploration missions.
Physical characteristics: Original contains color illustrations
形態: カラー図版あり
レポート番号: JAXA-RR-23-006E
連携機関・データベース国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）
提供元機関・データベース宇宙航空研究開発機構 : 宇宙航空研究開発機構リポジトリ