Direct Determination of the Activation Energy for Diffusion of OH Radicals on Water Ice

Miyazaki A.; Tsuge M.; Hidaka H.; Nakai Y.; Watanabe N.

タイトル	en Direct Determination of the Activation Energy for Diffusion of OH Radicals on Water Ice
作成者	en Miyazaki, A. en Tsuge, M. en Hidaka, H. en Nakai, Y. en Watanabe, N. NRID 1000050271531
アクセス権	metadata only access
主題	NDC 420
内容注記	Abstract en Using a combination of photostimulated desorption and resonance-enhanced multiphoton ionization methods, the behaviors of OH radicals on the surface of an interstellar ice analog were monitored at temperatures between 54 and 80 K. The OH number density on the surface of ultraviolet-irradiated compact amorphous solid water gradually decreased at temperatures above 60 K. Analyzing the temperature dependence of OH intensities with the Arrhenius equation, the decrease can be explained by the recombination of two OH radicals, which is rate-limited by thermal diffusion of OH. The activation energy for surface diffusion was experimentally determined for the first time to be 0.14 +/- 0.01 eV, which is larger than or equivalent to those assumed in theoretical models. This value implies that the diffusive reaction of OH radicals starts to be activated at approximately 36 K on interstellar ice.
出版者	en American Astronomical Society
日付	Issued2022-11-14
言語	eng
資源タイプ	journal article
出版タイプ	NA
資源識別子	HDL http://hdl.handle.net/2115/87548
関連	isIdenticalTo DOI https://doi.org/10.3847/2041-8213/ac9d30
収録誌情報	PISSN 2041-8205 en The Astrophysical journal letters 巻940 開始ページL2
コンテンツ更新日時	2023-07-26