Collaborative Research: Chemistry and Structure Formation at High Redshift

这是一个与菲利普·斯坦赛尔博士(乔治亚大学，AST0087172)和斯蒂芬·勒普(内华达大学，拉斯维加斯，AST0087348)合作的研究项目。这个计划将建立模型来研究第一批宇宙物体的形成。这些模型将描述早期宇宙中由原始气体形成的第一批束缚物体的历史。它们将包括依赖于时间的、非平衡的化学能级、原子能级和分子能级布居的耦合演化，以及由于原始气体中的化学反应而贡献的分子的非平衡振动能级布居。这些模型可以用来建议从太空观察早期宇宙的红外结构的策略。这个项目将使用天体物理模型来研究第一个宇宙物体的形成。这些模型将计算从原始气体形成的第一个束缚物体的依赖于时间的非平衡化学、原子和分子水平的布居、热力学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、耦合的进化模型。此外，这个项目将研究由于化学反应而做出贡献的原始分子的显式非平衡振动能级布居，从而改进分子冷却的测定和对原始云发射光谱的预测。发射光谱将被用来建议用下一代红外太空望远镜观察这些物体的最有可能的方式。所需的原子和分子数据以及衍生的冷却功能将被汇编并发布在万维网上。无法获得的数据，主要涉及特定于旋转状态的分子碰撞，将用现有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跟踪原星系和原星的形成，直到人口II时代的开始。这些研究将与未来利用NGST、SIRTF、FIRST和Astro-F以及地面望远镜进行的天基观测的解释和规划有关。该项目的资金由NSF河外天文与宇宙学计划(AST/EXC)提供。*

AST-0088213Alexander DalgarnoThis is a collaborative research project with Drs Phillip Stancil, (the University of Georga, AST0087172), and Stephen Lepp, (University of Nevada, Las Vegas, AST0087348). 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).***