Collaborative Research: Fast Dynamos in the Computer, the Galaxy, and the Laboratory

AST 0125544 Lazarian该研究项目旨在了解天体物理磁场的产生和演化。磁场在许多天体物理过程中起着决定性的作用，从介导星星的形成和在无处不在的吸积盘中传输角动量到影响星系团内的加热/冷却。在所有这些情况下，大的磁流雷诺数要求通过快速重联实现磁场拓扑结构的任何变化，而磁场的产生需要快速发电机。该项目利用最新进展的数值能力来测试最近先进的快速重联和快速发电机理论。它还提出了重联理论的进一步发展，理论和数值结果与液体钠测量的比较，以及银河发电机的模拟。这项工作的另一个非常重要的成果将是开发一个并行AMR MI-ID代码，RIEMANN，用于模拟旋转天体物理系统中的MHD现象。这将是一个通用的实用程序，将广泛提供给社区。该项目的资金由美国国家科学基金会的河外天文宇宙学计划（AST/EXC）提供。

AST 0125544LazarianThis research program is aimed at understanding the generation and evolution of astrophysical magnetic fields. Magnetic fields play decisive role in many astrophysical processes from mediating star formation and transporting angular momentum in ubiquitous accretion disks to influencing heating/cooling within clusters of galaxies. In all these situations, the large magnetic Reynolds numbers of the flows require that any changes of magnetic field topology be implemented through fast reconnection, while magnetic field generation requires fast dynamo.The project makes use of recent advances in numerical capabilities to test recently advanced theories of fast reconnection and fast dynamos. It also proposes further development of reconnection theory, comparisons of theoretical and numerical results with liquid sodium measurements, and simulations of the galactic dynamo. Another very important outcome of this effort will be the development of a parallel AMR MI-ID code, RIEMANN, for simulating MHD phenomena in rotating astrophysical systems. This will be a general-purpose utility that will be made widely available to the community. Funding for this project was provided by the NSF program for Extragalactic Astronomy & Cosmology (AST/EXC).***