Probing the Astronomical Gas-Grain Interaction: Formation and Morphology of Icy Grain Materials

探索天文气体-颗粒相互作用：冰颗粒材料的形成和形态

• 批准号: EP/D506158/1
• 负责人: Martin McCoustra
• 金额: $ 50.24万
• 依托单位: Heriot-Watt University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FD506158%2F1
• 关键词: Probing; Astronomical; Gas; Grain; Interaction

The importance of molecules to the evolution of the cosmos today should not be under-estimated. Molecules play a key role in the star formation process, indeed without complex molecules it is unlikely that there would ever be small, long-lived stars of the type represented by our own star. Without such stars, it is unlikely that life could have even evolved to recognise this fact. Not only do molecules act as markers for regions of star formation, or as chemical clocks through which we remotely probe the timescale of the star forming process, but also as active radiative coolants during the early stages of the collapse of a gas clump to form a pre-stellar object. It is through this latter role that chemistry can be said to actively control the cosmos!Over the past 25 years or so, through interaction of the molecular astrophysics and chemical physics communities, the main processes by which interstellar molecules are formed and destroyed have become reasonably understood. The role of these molecules in tracing the gas in star forming regions, and especially in actively controlling the evolution of the gas through cooling, have been thoroughly explored. The essential thrust of research in this area during the last decade has been that purely gas phase chemistry cannot successfully account for the variety and richness of interstellar chemistry. Nor can it account for the roles that molecules play in astronomy in determining the thermal and magnetic pressures in the gas. Thus, the contribution of gas phase chemistry must be complemented by the gas-dust interactions. These interactions are particularly important in denser regions of molecular clouds where star formation is occurring. The main interactions are direct chemical reactions at grain surfaces, freeze-out of gaseous species to form molecular ices, processing of molecular ices by ambient UV, desorption of molecules from the ice surface, and evaporation of ice films on dust near hot stars. Interaction with the surface science community is recent and is bringing substantial benefits through an increased understanding of the processes that constitute the gas-grain interaction. However, what we consider to be the most important aspects of fundamental surface science required for a fuller understanding of the gas-grain interaction have yet to be addressed and these include the formation of simple molecular ices on cold grains, which is the focus of this proposal.

分子对今天宇宙演化的重要性不应低估。分子在星星的形成过程中起着关键的作用，事实上，如果没有复杂的分子，就不可能有我们自己的星星所代表的那种小而长寿的恒星。如果没有这样的恒星，生命甚至不可能进化到认识到这一事实。分子不仅作为星星形成区域的标记，或者作为化学钟，我们通过它来远程探测星星形成过程的时间尺度，而且在气体团坍缩形成恒星前物体的早期阶段，分子还作为活跃的辐射冷却剂。正是通过后一种作用，化学可以说是积极地控制着宇宙！在过去25年左右的时间里，通过分子天体物理学和化学物理学界的相互作用，星际分子形成和破坏的主要过程已经得到了合理的理解。这些分子在追踪星星形成区域的气体中的作用，特别是在通过冷却主动控制气体的演化中的作用，已经被彻底探索。在过去的十年里，这一领域的研究的主要目的是纯粹的气相化学不能成功地解释星际化学的多样性和丰富性。它也不能解释分子在天文学中决定气体中的热压力和磁压力的作用。因此，气相化学的贡献必须由气尘相互作用来补充。这些相互作用在星星形成的分子云密集区域尤为重要。主要的相互作用是颗粒表面的直接化学反应，气态物质冻结形成分子冰，环境紫外线对分子冰的处理，分子从冰表面的解吸，以及热恒星附近尘埃上的冰膜蒸发。与表面科学界的互动是最近的，并通过增加对构成气体-颗粒相互作用的过程的理解带来了实质性的好处。然而，我们认为是基础表面科学的最重要的方面，需要更充分地了解气体-颗粒相互作用尚未得到解决，其中包括在冷颗粒上形成简单的分子冰，这是本提案的重点。

项目成果

Wannier-Mott Excitons in Nanoscale Molecular Ices.

纳米级分子冰中的万尼尔-莫特激子。

• DOI: 10.1103/physrevlett.119.157703
• 发表时间: 2017
• 期刊: Physical review letters
• 影响因子: 8.6
• 作者: Chen YJ

Probing model interstellar grain surfaces with small molecules

• DOI: 10.1093/mnras/stv425
• 发表时间: 2015-05-11
• 期刊: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
• 影响因子: 4.8
• 作者: Collings, M. P.;Frankland, V. L.;McCoustra, M. R. S.
• 通讯作者: McCoustra, M. R. S.

Surface Science Investigations of Icy Mantle Growth on Interstellar Dust Grains in Cooling Environments

冷却环境中星际尘埃颗粒上冰幔生长的表面科学研究

• DOI: 10.1021/acsearthspacechem.9b00052
• 发表时间: 2019
• 期刊: ACS Earth and Space Chemistry
• 影响因子: 3.4
• 作者: Marchione D

Physics and chemistry on the surface of cosmic dust grains: a laboratory view

宇宙尘埃颗粒表面的物理和化学：实验室观点

• DOI: 10.1080/0144235x.2021.1918498
• 发表时间: 2021
• 期刊: International Reviews in Physical Chemistry
• 影响因子: 6.1
• 作者: Potapov A

Impact of oxygen chemistry on model interstellar grain surfaces.

氧化学对模型星际颗粒表面的影响。

• DOI: 10.1039/c7cp05480g
• 发表时间: 2018
• 期刊: PCCP
• 作者: Rosu-Finsen A