Cosmic Ray Hydrodynamics

宇宙射线流体动力学

• 批准号: 0907837
• 负责人: Ellen Zweibel
• 金额: $ 60.04万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0907837&HistoricalAwards=false
• 关键词: Cosmic; Ray; Hydrodynamics

AST-0907837ZweibelInterstellar and intergalactic gas is pervaded by relativistic charged particles known as cosmic rays, which account for a significant fraction of the energy density in the gas. A fluid theory of cosmic rays has been developed in which collisions with tiny electromagnetic fluctuations mimic collisions with particles, capturing cosmic ray physics on large scales and allowing some beautiful simulations of galaxy clusters and large scale structure formation. This project will extend and generalize the fluid picture of cosmic rays so as to capture viscous effects and to treat cosmic ray interaction with very weak magnetic fields in the intergalactic medium and in galaxies and galaxy clusters at early times. This improved picture will then be applied to assess the thermal stability and overall viscosity of intracluster gas, to estimate the rate at which intergalactic plasma is heated by cosmic rays, and to study the effects of cosmic rays on the stability of hot X-ray cavities in clusters. This work develops microscale physics through analytic calculation and state-of-the-art numerical simulations of restricted scope. The small scale processes that will be studied also apply to interstellar environments, to pulsar wind nebulae, and even to laboratory plasmas.The research will help to build bridges between the plasma physics and high energy neutrino astrophysics groups at the University of Wisconsin. The work involves postdoctoral training, undergraduate research, and public outreach using existing facilities and programs.This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).

AST-0907837 Zweibel星际和星系际气体中弥漫着被称为宇宙射线的相对论性带电粒子，这些粒子占气体能量密度的很大一部分。 宇宙射线的流体理论已经发展起来，其中微小电磁波动的碰撞模拟与粒子的碰撞，捕获大尺度上的宇宙射线物理学，并允许一些星系团和大尺度结构形成的美丽模拟。 该项目将扩大和概括宇宙射线的流体图像，以便捕捉粘性效应，并处理宇宙射线与星系间介质以及星系和星系团早期非常弱的磁场的相互作用。 这一改进后的图像将用于评估团内气体的热稳定性和整体粘度，估计星系间等离子体被宇宙射线加热的速率，并研究宇宙射线对团内热X射线腔稳定性的影响。 这项工作通过有限范围的解析计算和最先进的数值模拟来发展微尺度物理。 研究的小尺度过程也适用于星际环境、脉冲星风星云、甚至实验室等离子体。这项研究将有助于在威斯康星州大学的等离子体物理和高能中微子天体物理研究组之间建立桥梁。 这项工作涉及博士后培训，本科生研究和利用现有设施和计划的公共宣传。该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。