返回
Episodic explosions in interstellar ices
DOI:10.1093/mnras/sts601.png)
摘要
En 中文
We present a model for the formation of large organic molecules in dark clouds. The molecules are produced in the high-density gas phase that exists immediately after ice mantles are explosively sublimated. The explosions are initiated by the catastrophic recombination of trapped atomic hydrogen. We propose that, in molecular clouds, the processes of freeze-out on to ice mantles, accumulation of radicals, explosion and then rapid (three-body) gas-phase chemistry occurs in a cyclic fashion. This can lead to a cumulative molecular enrichment of the interstellar medium. A model of the time-dependent chemistries, based on this hypothesis, shows that significant abundances of large molecular species can be formed, although the complexity of the species is limited by the short expansion time-scale in the gas, immediately following mantle explosion. We find that this mechanism may be an important source of smaller organic species, such as methanol and formaldehyde, as well as precursors to bio-molecule formation. Most significantly, we predict the gas-phase presence of these larger molecular species in quiescent molecular clouds and not just dynamically active regions, such as hot cores. As such the mechanism that we propose complements alternative methods of large molecule formation, such as those that invoke solid-state chemistry within activated ice mantles.
Keyword:
astrochemistry
molecular processes
ISM: clouds
ISM: molecules
AI总结
对已上传原文的论文进行重点信息的提取,主要内容包括:简要概述、研究摘要、背景介绍、关键亮点、图文解析、展望与总结。
期刊
IF:
4.8
论文数:
7.1W
被引数:
25.0W

