从纯CO冰和CO在无形固体水上的IR诱导的CO光吸附
Laura Slumstrup1, John D Thrower1, Johanna G M Schrauwen2
1Center for Interstellar Catalysis, Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark.
概括
红外光子可以导致一氧化碳 (CO) 从星际冰层中脱离. 从水冰转移到二氧化碳的能量转移对于二氧化碳脱吸比直接的二氧化碳激发更有效.
科学领域:
- 天体化学是天体化学.
- 星际介质物理 星际介质物理
- 表面科学是一门科学.
背景情况:
- 一氧化碳 (CO) 在恒星间冰层地幔中至关重要,影响复杂的有机分子形成.
- 星际尘埃颗粒受到辐射的影响,将固态和气相化学联系起来.
- 红外 (IR) 光子在密集的分子云中主导辐射场,与紫外光子不同.
研究的目的:
- 研究从星际冰同类物质中IR光子诱导的二氧化碳脱落.
- 将CO/水冰的CO脱吸产量与纯CO冰进行比较.
- 确定能量转移在红外驱动绝吸过程中的作用.
主要方法:
- 在无形固体水 (ASW) 上沉积CO,形成多层膜.
- 使用FELIX IR自由电子激光器 (FEL-2) 对冰膜进行辐射.
- 红外光谱学和质谱学用于检测脱氧化碳.
主要成果:
- 底层ASW中的令人兴奋的振动模式诱导了显著的CO脱吸.
- 对CO的拉伸模式的直接激发导致了低效的CO脱吸.
- 脱吸效率表明,星际冰层内有高效的能量转移.
结论:
- 冰中的能量转移是红外光子诱导CO等挥发性物种脱离的重要途径.
- 这种机制对于理解密集云层中固态冰和气相分子之间的联系很重要.
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