Gas Accretion and the Disk-Halo Interface

气体吸积和盘晕界面

• 批准号: 1008134
• 负责人: Greg Bryan
• 金额: $ 46.93万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1008134&HistoricalAwards=false
• 关键词: Gas; Accretion; Disk; Halo; Interface

This project addresses the issue of how gas flows into spiral galaxies, a process essential to support the long histories of star formation in these systems. The PI and co-PI will use the adaptive-mesh hydrodynamics code Enzo to carry out two series of simulations of gas flow into disk galaxies. The first series will consist of very high resolution cosmological simulations of galaxy halos similar to that of the Milky Way; the goal is to resolve the interface between the cold and hot phases of the gas and determine whether cold clouds condensing from the hot phase make their way to the disk. The second series will simulate a vertical column in and above the galactic disk, with the goal of determining whether and how thermal instabilities serve to channel the cooling medium into the disk. The code will also be used to construct simulated observations of emission and absorption lines arising in the cooling medium, for comparison with available spectroscopic data. The work will in part be performed by, and will include the mentoring of, a postdoctoral fellow. The postdoc, PI, and co-PI will participate in a program to train graduate students to visit middle schools to conduct interactive outreach programs, and visualizations constructed from the simulations will be made available for planetarium shows or other public venues.

该项目解决了气体如何流入螺旋星系的问题，这是支持这些系统中恒星形成的悠久历史所必需的过程。 PI 和 co-PI 将使用自适应网格流体动力学代码 Enzo 对流入盘状星系的气体进行两个系列的模拟。第一个系列将包括与银河系类似的星系晕的高分辨率宇宙学模拟；目标是解析气体冷相和热相之间的界面，并确定从热相凝结的冷云是否会到达圆盘。第二个系列将模拟银盘内部和上方的垂直柱，目的是确定热不稳定性是否以及如何将冷却介质引导到银盘中。该代码还将用于构建冷却介质中出现的发射线和吸收线的模拟观察结果，以便与可用的光谱数据进行比较。这项工作部分将由博士后研究员完成，并包括其指导。博士后、首席研究员和联合首席研究员将参加一项培训研究生访问中学开展互动推广项目的计划，并且根据模拟构建的可视化将可用于天文馆表演或其他公共场所。