Multi-resolution global magnetohydrodynamic magnetosphere studies of the bursty bulk flows in the magnetotail

Tuesday, 16 December 2014
Michael James Wiltberger, National Center for Atmospheric Research, High Altitude Observatory, Boulder, CO, United States, John Lyon, Dartmouth College, Hanover, NH, United States and Viacheslav G Merkin, The Johns Hopkins University, Laurel, MD, United States
The Lyon-Fedder-Mobarry global magnetohydrodynamic magnetosphere simulation has a robust history of producing bursty bulk flow (BBFs) events in the magnetotail under a variety of solar wind conditions. Many spacecraft missions including Geotail and THEMIS have also observed BBFs. Superposed epoch analysis has been used to develop the general properties and distributions of these events. Using a set of idealized solar wind conditions we compare the results of simulations over an order of magnitude in computational range with the observed properties of BBFs. This comparison includes a detail examination of a typical BBF or flow channel event as it develops in the mid-tail region and eventually breaks in the inner magnetosphere. As these flow channels propagate Earthward they develop vortical flows at the leading edge and have field-aligned currents that couple with the ionosphere. An additional area of investigation will be to determine the factors that the to creation of a BBF in a specific location along the mid-tail reconnection line. We have also developed tools for automatically identifying the BBFs in the simulation results we compare these result via a superposed epoch analysis with similar analysis done with the Geotail and THEMIS datasets.