Galaxy-Cluster Baryons and the Cooling-Flow Problem

星系团重子和冷却流问题

• 批准号: 0549577
• 负责人: Benjamin Chandran
• 金额: --
• 依托单位: University of New Hampshire
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-15 至 2008-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0549577&HistoricalAwards=false
• 关键词: Galaxy; Cluster; Baryons; Cooling; Flow

AST-0507399ChandranHeating of intra-cluster plasma holds the key to some of the central problems in the study of galaxy-cluster baryons, notably the 'cooling flow problem' and problems of cluster formation, and two of the most important heat sources are central active galactic nuclei (AGN) and thermal conduction. This project will carry out high-resolution two-fluid simulations of AGN-heated cluster cores, including correct treatment of cosmic-ray pressure and buoyancy, turbulent mixing, and thermal conduction, as well as test-particle simulations of electron diffusion in turbulent magnetic fields, to improve previous approximate theories of thermal conduction. The investigation will rigorously test whether AGN heating solves the cooling flow problem, and will also show how to modify cluster-formation simulations to account for these two important heating mechanisms. This will lead to a better understanding of the relation between cluster masses and observables, and assist cluster surveys to constrain cosmological parameters.The project includes junior researcher training, but also a major outreach effort through the University's Upward Bound Project, which targets low-income and first-generation students.

AST-0507399星系团内等离子体的加热是星系团重子研究中一些核心问题的关键，特别是“冷却流问题”和星系团形成问题，其中两个最重要的热源是中央活动星系核和热传导。 该项目将对活动星系核加热的星系团核心进行高分辨率双流体模拟，包括正确处理宇宙射线压力和浮力、湍流混合和热传导，以及湍流磁场中电子扩散的试验粒子模拟，以改进以前的热传导近似理论。 这项研究将严格测试活动星系核加热是否解决了冷却流问题，并将展示如何修改集群形成模拟来解释这两个重要的加热机制。 这将导致更好地了解星团质量和可观测量之间的关系，并协助星团调查限制宇宙学参数，该项目包括初级研究人员培训，但也通过该大学的向上拓展项目进行了重大的外联工作，该项目的目标是低收入和第一代学生。