Collaborative Research: Chemistry and Structure Formation at High Redshift

合作研究：高红移下的化学和结构形成

• 批准号: 0087348
• 负责人: Stephen Lepp
• 金额: $ 8.58万
• 依托单位: University of Nevada Las Vegas
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-01 至 2004-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0087348&HistoricalAwards=false
• 关键词: Collaborative; Research; Chemistry; Structure; Formation

AST-0087348Stephen LeppThis is a collaborative research project with Drs Phillip Stancil, (the University of Georga, AST0087172), and Alexander Dalgarno, (Harvard University, AST0088213). This program will construct models to investigate the formation of the first cosmological objects. These models will describe the history of the first bound objects to form from the primordial gas in the early universe. They will include the coupled evolution of the time-dependent, nonequilibrium chemical, atomic and molecular level populations as well as the nonequilibrium rovibrational level populations of the molecules with contributions due to chemical reactions in the primordial gas. The models can be used to suggest strategies for observing structures in the early universe in the Infrared from space.This program will use astrophysical modeling to investigate the formation of the first cosmological objects. These models will compute the coupled evolution of the time-dependent nonequilibrium chemical, atomic and molecular level population, thermal, and hydrodynamic history of the first bound objects to form from the primordial gas. This will be the first time such extensive, coupled evolution models have been attempted. In addition, this project will investigate the explicit nonequilibrium rovibrational level populations of the primordial molecules with contributions due to chemical reactions, resulting in an improved determination of molecular cooling and the prediction of the emission spectra of primordial clouds. The emission spectra will be used to suggest the most likely ways these objects may be observed with the next generation of infrared space telescopes. The needed atomic and molecular data and derived cooling functions will be assembled and posted on the World Wide Web. The data that is not available, primarily involving rovibrational state-specific molecular collisions, will be computed with established quantum-mechanical techniques. The studies of the primordial gas will be extended to follow protogalaxy and protostar formation under increasing metallicity and radiation field conditions to the beginning of the era of Population II. These studies will be relevant to the interpretation and planning of future space-based observations with NGST, SIRTF, FIRST, and Astro-F and ground-based telescopes. Funding for this project was provided by the NSF program for Extragalactic Astronomy & Cosmology (AST/EXC).***

AST-0087348Stephen Lepp这是与 Phillip Stancil 博士（乔治亚大学，AST0087172）和 Alexander Dalgarno（哈佛大学，AST0088213）的合作研究项目。该计划将构建模型来研究第一个宇宙物体的形成。这些模型将描述早期宇宙中由原始气体形成的第一个束缚物体的历史。它们将包括时间依赖性、非平衡化学、原子和分子水平群体的耦合演化，以及分子的非平衡振动水平群体的耦合演化，其贡献归因于原始气体中的化学反应。这些模型可用于提出从太空红外观测早期宇宙结构的策略。该计划将使用天体物理模型来研究第一个宇宙物体的形成。这些模型将计算由原始气体形成的第一个束缚物体的时间依赖性非平衡化学、原子和分子水平布居、热和流体动力学历史的耦合演化。这将是第一次尝试如此广泛的耦合进化模型。 此外，该项目还将研究因化学反应而做出贡献的原始分子的显式非平衡旋转振动水平群体，从而改进分子冷却的确定和原始云发射光谱的预测。发射光谱将用于建议下一代红外太空望远镜观察这些物体的最可能的方式。所需的原子和分子数据以及派生的冷却函数将被组装并发布在万维网上。无法获得的数据，主要涉及振动态特定分子碰撞，将使用已建立的量子力学技术进行计算。对原始气体的研究将扩展到在金属丰度和辐射场条件增加的情况下原星系和原恒星的形成，直至人口 II 时代的开始。这些研究将与 NGST、SIRTF、FIRST、Astro-F 和地面望远镜未来天基观测的解释和规划相关。该项目的资金由 NSF 河外天文学和宇宙学计划 (AST/EXC) 提供。***