Quantitative insight into interstellar turbulence

对星际湍流的定量洞察

• 批准号: 1212096
• 负责人: Alexandre Lazarian
• 金额: $ 29.99万
• 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: 2012
• 资助国家: 美国
• 起止时间: 2012-07-01 至 2017-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1212096&HistoricalAwards=false
• 关键词: Quantitative; insight; into; interstellar; turbulence

This is a continuation of Dr. Lazarian's theoretical work on the influence of magnetic field diffusion in turbulent star-forming clouds on the star formation process. The appearance, evolution, and overall properties of a spiral galaxy are strongly influenced by its interstellar medium (ISM). In turn, the nature of the ISM and many processes within it, such as star formation, are determined by the magnetic turbulence that stirs the ISM. Properties of turbulent fluids cannot be confidently understood using only numerical approaches; and the fluid motions simulated by computers differ from astrophysical ones by a huge difference in Reynolds numbers.The present work focuses on the role that magnetic reconnection plays in star formation, and investigates the sources and effects of turbulence in different phases of the ISM. Although turbulence is chaotic, it can be described and understood by applying well defined statistical laws to solve astrophysical problems.The work improves the comparison of theory with observations. The studies employ well-tested numerical codes already in place. The principal investigator and his team will continue to develop, test, and apply new tools for extracting properties of turbulence (such as turbulence spectra and sonic Mach number of turbulence) from observations.The statistical tools from this study are made publicly available and provide new tools to the observational community to study turbulence, its driving, and its magnetization. A graduate student will work on this project. This project also offers Research Experience for Undergraduate (REU) students.

这是Lazarian博士对磁场扩散在湍流恒星形成云中对恒星形成过程的影响的理论工作的延续。螺旋星系的外观，进化和整体性质受其星际介质（ISM）的强烈影响。反过来，ISM的性质和其中的许多过程（例如恒星形成）是由搅动ISM的磁性湍流决定的。只使用数值方法就无法自信地理解湍流的特性。计算机模拟的流体运动与天体物理的动作不同，雷诺数的差异很大。目前的工作着重于磁重新连接在恒星形成中的作用，并研究了ISM不同阶段湍流的来源和影响。尽管湍流是混乱的，但可以通过应用明确的统计定律来解决天体物理问题来描述和理解。这项工作改善了理论与观察的比较。这些研究采用了经过良好测试的数值代码。首席研究员及其团队将继续从观察值中开发，测试和应用新工具来提取湍流（例如湍流光谱和湍流的声音马赫数）。该研究的统计工具已公开可用，并为观察性社区提供了新的工具，以研究湍流，湍流及其驱动力。研究生将从事这个项目。该项目还为本科生（REU）学生提供研究经验。