Simulating CME Eruptions from Active Regions

Friday, 19 December 2014: 8:30 AM
Ward Manchester and Bart van der Holst, University of Michigan, Ann Arbor, MI, United States
Fast coronal mass ejections (CMEs) typically erupt from the filament channels of active regions where the magnetic field is in a highly non potential state. In this talk, we discuss two numerical models under development that will simulate the evolution of active regions and the buildup of magnetic energy that leads to filament eruptions and CMEs. The first model, the so called regional model simulates the area of an active region in a domain that extends from just above the photosphere at its base to a height of 100 Mm in the low corona. The physics of this model is extended magnetohydrodynamics (MHD), which includes such physical processes as field aligned heat conduction, radiative losses, and tabular equation of state that allow for a self-consistent treatment of the atmosphere including the transition region. For this model, boundary conditions for the magnetic field fields are specified directly from HMI vector magnetogram observations. The second model addresses the buoyant rise of magnetic flux from the convection zone through the photosphere to allow for the self consistent formation and evolution of active regions that leads to the buildup of magnetic free energy. We compare results from this second model to SDO/HMI observations of the 7 January 2014 events to show that the simulation has captured the basic physics of magnetic field evolution an energy build up necessary for large-scale eruptions.