Data-Model Comparisons of Plasma Sheet Ion Temperatures during Moderate Geomagnetic Storms

Wednesday, 17 December 2014
Amy M Keesee1, Raluca Ilie2, Michael Warren Liemohn2, Bianca Trigo3, Gunner Robison3 and Jerry Carr, Jr.3, (1)West Virginia University, Morgantown, WV, United States, (2)University of Michigan, Ann Arbor, MI, United States, (3)Texas Lutheran University, Seguin, TX, United States
Ion heating occurs during geomagnetic storms as a result of many physical processes, including magnetic reconnection and adiabatic heating. Ion temperatures calculated from TWINS energetic neutral atom (ENA) data provide a global view of regions of heated ions in the plasma sheet. Two storms of similar, moderate magnitude are analyzed, a coronal mass ejection (CME)-driven storm that occurred on 26 September 2011 and a high speed stream (HSS)-driven storm on 13 October 2012. We present a comparison of the ion temperatures during the storms to patterns observed in a superposed epoch analysis of ion temperatures [Keesee et al., 2013] and compare the October storm to a previously analyzed HSS-driven storm [Keesee et al., 2012]. We also present a comparison of observed ion temperatures to those calculated from a simulation of each storm using the Space Weather Modeling Framework, including the BATS-R-US MHD model coupled with the HEIDI inner magnetosphere model.