IGPP Seminar Series

The Impact of Sudden Storm Commencement on Magnetotail Ions

by Vahe Peroomian
IGPP, UCLA

Abstract

The sudden storm commencement (SSC) caused by the impact of coronal mass ejections (CMEs) on Earth’s magnetosphere is the most violent aspect of geomagnetic storms. We have modeled this impact and its effects on magnetotail ions by using a combination of global magnetohydrodynamic (MHD) simulations and large-scale kinetic particle tracing calculations. We selected three moderate to large CME-driven geomagnetic storms for which upstream solar wind and interplanetary magnetic field (IMF) data and observations in the magnetotail and near-Earth plasma sheet are available. For each event, we have run a global MHD simulation of the event using upstream solar wind and IMF data. Ion trajectories are then traced from the solar wind, upstream of the bow shock, and from the ionosphere beginning 3-4 hours prior to the SSC to obtain global distributions of ions in the magnetotail and inner magnetosphere just prior to, during, and immediately after the SSC. Doing so allows us to delineate the effect of the sudden storm commencement on ion energization and injection into the inner magnetosphere, and to compare the effect of the SSC with that of storm-time substorms.
Tuesday, 21 October 2008
3853 Slichter Hall
Refreshments at 3:45 PM
Lecture at 4:00 PM