Stellar Chemistry

恒星化学

• 批准号: 0807356
• 负责人: M. Bruce Fegley
• 金额: $ 15.04万
• 依托单位: Washington University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0807356&HistoricalAwards=false
• 关键词: Stellar; Chemistry

This project is a three-year theoretical investigation into the gas and condensation chemistry of the elements in astronomical dust forming environments, with an emphasis on evolved stars. The research is an expansion of theoretical work that Dr. Lodders carried out previously. Here, working with collaborators and students, Dr. Lodders will provide a fundamental framework for interpreting the chemical composition of the gas and condensates in stellar environments. The work is important to several areas in astrophysics and cosmochemistry as chemistry takes over as soon as physical conditions allow gas molecule and condensate formation. Systems where molecular gas and dust chemistry is important include protostellar disks (with and without planetary formation); and ejecta of evolved stars that feed dust and gas to the interstellar medium, from which new stellar and planetary systems originate. The project, which focuses on chemistry at non-solar metallicities is highly relevant to planetary formation around high metallicity stars, as well as condensation around low-metallicity stars or even in dusty galaxies at high red-shift. The project is complementary to spectroscopic studies of the molecular dominated atmospheres and circumstellar shells of red giant stars and other ?dusty? objects. The computations to be carried out here can be used as a guide to interpret observations obtained from instruments such as the Hubble Space Telescope (HST), the Infrared Space Observatory (ISO), the Spitzer Space Telescope, the Stratospheric Observatory for Infrared Astronomy (SOFIA), and the Herschel Space Observatory. Key to the project are ongoing collaborations with observers to develop and test chemical fractionation models. The work is also complementary to the analysis of presolar grains (stardust) isolated from meteoritesThe ongoing collaborations of researchers with expertise in different disciplines will enhance interdisciplinary connections between meteoritics, astrophysics, and observational astronomy as well as strengthening international networks. The project also includes the participation of undergraduate students, and will provide them with valuable research experience, helping to train the next generation of astronomers. Results will be described in scientific papers, at professional meetings, and in public lectures. Expansions of Dr. Lodder?s website are planned as part of this effort to make computational results widely available.

该项目是一个为期三年的理论研究，研究天文尘埃形成环境中元素的气体和凝聚化学，重点是演化的恒星。这项研究是Lodders博士以前进行的理论工作的扩展。Lodders博士将与合作者和学生合作，为解释恒星环境中气体和冷凝物的化学成分提供一个基本框架。这项工作对天体物理学和宇宙化学的几个领域都很重要，因为一旦物理条件允许气体分子和凝析油形成，化学就会接管。分子气体和尘埃化学很重要的系统包括原恒星盘（有或没有行星形成）;以及演化恒星的喷出物，它们将尘埃和气体输送到星际介质，新的恒星和行星系统由此产生。该项目的重点是非太阳金属丰度的化学，与高金属丰度恒星周围的行星形成以及低金属丰度恒星周围的凝聚，甚至在高红移的尘埃星系中高度相关。该项目是补充光谱研究的分子占主导地位的大气和拱壳的红巨星和其他？尘土飞扬？对象这里进行的计算可以作为指导，解释从哈勃太空望远镜（HST），红外空间天文台（ISO），斯皮策太空望远镜，平流层红外天文台（索菲亚）和赫歇尔空间天文台等仪器获得的观测结果。该项目的关键是正在进行的与观察员的合作，以开发和测试化学分馏模型。这项工作也是对从陨石中分离出的前太阳颗粒（星尘）的分析的补充。具有不同学科专门知识的研究人员正在进行的合作将加强陨石学、天体物理学和观测天文学之间的跨学科联系，并加强国际网络。该项目还包括本科生的参与，并将为他们提供宝贵的研究经验，帮助培养下一代天文学家。研究结果将在科学论文、专业会议和公开讲座中进行描述。洛德博士的扩展？的网站计划作为这一努力的一部分，使计算结果广泛提供。