日本地球惑星科学連合2019年大会

講演情報

[J] 口頭発表

セッション記号 M (領域外・複数領域) » M-IS ジョイント

[M-IS11] 水惑星学

2019年5月27日(月) 15:30 〜 17:00 A02 (東京ベイ幕張ホール)

コンビーナ:関根 康人(東京工業大学地球生命研究所)、臼井 寛裕(東京工業大学地球生命研究所)、福士 圭介(金沢大学環日本海域環境研究センター)、渋谷 岳造(海洋研究開発機構)、座長:関根 康人(東京大学大学院理学系研究科地球惑星科学専攻)、福士 圭介臼井 寛裕

16:45 〜 17:00

[MIS11-12] Measurement technique to quantify OH radicals photochemically generated on the ice surface

*薮下 彰啓1西本 寛彰1原田 明1 (1.九州大学大学院総合理工学研究院)

キーワード:OHラジカル、氷、真空紫外光、赤外反射吸収分光法、表面

Reaction processes of many molecules are presumably involved in oxidative atoms/molecules generated by photodecomposition of molecules adsorbed on cold dust grains. Hydroxyl (OH) radicals are considered as one of them. The chemistry of OH radicals plays a key role in the radiolysis and photolysis of water-rich ices of astrochemical origin. Measurements of OH radical in water-ice in the laboratory have been done by UV, EPR, X-ray absorption, and infrared absorption measurements. However, quantification of OH radicals on the ice surface has not yet been made. In the present work, we have tried to develop the measurement technique to quantify OH radicals photochemically generated on the surface of ice film. In this technique, OH are converted to the different molecule by utilizing the chemical reaction, and monitored through reflection absorption infrared spectroscopy. We have investigated the effect of ice temperature on abundance of OH radicals on the ice surface at 8-70 K. In addition, the effect of ice surface morphology on abundance of OH radicals has been studied by preparing the amorphous solid water and polycrystalline ice. The present study experimentally shows both the temperature and surface morphology plays an important role in abundance of OH radicals on the ice surface.