NSWP: Modeling Coronal Mass Ejection (CME) Initiation with Magnetic Flux Emergence

该研究小组将通过模拟从对流区进入日冕的通量形成的太阳活动区，调查日冕物质抛射（CME）的根本原因。为了实现他们的目标，团队成员将利用密歇根大学辐射冲击流体动力学中心（CRASH）开发的新磁流体动力学（MHD）代码。这CRASH代码增加了辐射传输和先进的处理状态方程的MHD现有的模型在密歇根州开发的能力，并允许模拟通量出现从湍流对流区的电晕在一个单一的计算域。该项目的首席研究员将把这一数值通量出现部分纳入密歇根空间气象建模框架，以便将太阳活动区域尺度模型与延伸至地球的全球尺度日冕模型相结合。该模型的预测将与太阳大气中不同层次的观测结果进行比较，包括用日震学确定的对流区等离子体流场，用多普勒图确定的日冕流场，这个新的耦合模拟系统将通过模拟对流产生的磁通量来实现国家空间天气计划的一个关键目标进入日冕，爆发，然后作为CME传播到行星际空间。因此，它跨越了从太阳到地球的空间天气预报领域。这项研究还将支持本科和研究生教育。具体而言，申请的资金将主要用于支持一名研究生，而研究成果将纳入密歇根大学大气、海洋和空间科学系的课程。

This research team will investigate the fundamental causes of coronal mass ejections (CMEs) using simulations of solar active region formation by flux emergence from the convection zone into the corona. To accomplish their goals, the team members will utilize a new magnetohydrodynamics (MHD) code being developed by the Center for Radiation Shock Hydrodynamics (CRASH) at the University of Michigan. This CRASH code adds radiation transport and advance treatment of the equation-of-state to the MHD capabilities of existing models developed at Michigan, and will allow the simulation of flux emergence from a turbulent convection zone to the corona in a single computational domain. The Principal Investigator of this project will incorporate this numerical flux emergence component in Michigan's Space Weather Modeling Framework, in order to couple the solar-active-region-scale model to a global-scale coronal model extending to the Earth. The model's predictions will be compared to observations made at different levels in the solar atmosphere, including plasma flow fields in the convection zone determined with helioseismology, flow fields in the corona determined with Dopplergrams, and magnetic fields measured at the photosphere with vector magnetographs.This new coupled modeling system will address a key National Space Weather Program objective by simulating magnetic flux emerging from the convection zone into the solar corona, erupting and then propagating as a CME into interplanetary space. It thus spans the space weather forecasting domain from Sun to Earth. This research will also support undergraduate and graduate education. Specifically, the requested funding will primarily support a graduate student, while research results will be incorporated into courses in the Department of Atmospheric, Ocean, and Space Science at the University of Michigan.