Diffusion of atoms and molecules on interstellar dust grain and ice analogs

原子和分子在星际尘埃颗粒和冰类似物上的扩散

• 批准号: 1615897
• 负责人: Gianfranco Vidali
• 金额: $ 73.66万
• 依托单位: Syracuse University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2020-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1615897&HistoricalAwards=false
• 关键词: Diffusion; atoms; molecules; interstellar; dust; Diffusion; atoms; molecules; interstellar; dust

Interstellar space, or the space between the stars, contains extremely cold and tenuous clouds of gas seeded with tiny dust grains. Within the densest interstellar clouds, dust grains are coated with ice, providing sites for chemical reactions of simple atoms and molecules. Reactions on dust grains and ices can produce increasingly complex molecules, some of which are the building blocks of life. This research project will use advanced experimental and theoretical tools from a variety of scientific fields to study how atoms and molecules react on dust grains and ices under harsh conditions similar to those in space. Results from the study will help astronomers understand how processes on dust grains and ices can lead to the rich chemistry of space. The project will also train students in an interdisciplinary field at the forefront of astrophysical research. This project will combine proven experimental techniques (atomic and molecular beams, quadrupole mass spectrometry, and infrared spectroscopy) with new techniques (time-resolved reactive scattering) to obtain quantitative information on adsorption, diffusion, reaction, and desorption of atoms and molecules that are commonly found in the interstellar gas. Newly developed theoretical methods will be used to derive adsorption (sticking) and diffusion coefficients of the atoms and molecules from the experimental data. The data and derived parameters will be used in simulations of interstellar environments. The PI and his team will: (1) measure diffusion coefficients of atoms and molecules on surfaces of dust grain analogs and ices; (2) measure sticking coefficients of atoms and molecules on surfaces of various grain analogs; (3) perform theoretical analyses of the experimental data; (4) use the new diffusion coefficients in chemical models that will help interpret observations of interstellar clouds; and (5) provide the data in a format that can be used by astronomers studying the chemical evolution of the interstellar gas. The project will also support an undergraduate student, a graduate student, and a postdoctoral scholar at Syracuse University.

星际空间或恒星之间的空间包含非常寒冷的气体云层，这些气体是带有微小的灰尘颗粒的气体。 在最密集的星际云中，粉尘颗粒涂有冰，为简单原子和分子的化学反应提供了位置。 对粉尘颗粒和冰的反应会产生越来越复杂的分子，其中一些是生命的基础。 该研究项目将使用各种科学领域的先进的实验和理论工具来研究原子和分子如何在与太空中类似的恶劣条件下对粉尘粒和冰的反应。 该研究的结果将有助于天文学家了解尘埃谷物和冰的过程如何导致空间的丰富化学反应。 该项目还将在天体物理研究最前沿的跨学科领域培训学生。 This project will combine proven experimental techniques (atomic and molecular beams, quadrupole mass spectrometry, and infrared spectroscopy) with new techniques (time-resolved reactive scattering) to obtain quantitative information on adsorption, diffusion, reaction, and desorption of atoms and molecules that are commonly found in the interstellar gas. 新开发的理论方法将用于从实验数据中得出原子和分子的吸附（粘附）和扩散系数。 数据和派生参数将用于星际环境的模拟。 PI和他的团队将：（1）测量原子和分子在灰尘类似物和冰的表面上的扩散系数； （2）测量各种晶粒类似物表面上原子和分子的粘附系数； （3）对实验数据进行理论分析； （4）在化学模型中使用新的扩散系数，这将有助于解释星际云的观察； （5）以研究星际气体化学演化的天文学家可以使用的格式提供数据。 该项目还将支持锡拉丘兹大学的本科生，研究生和博士后学者。