SH33B-2469
Multi-Spacecraft Analysis of Energetic Heavy Ions and Interplanetary Shock Properties in Energetic Storm Particle Events at 1 AU
Wednesday, 16 December 2015
Poster Hall (Moscone South)
Robert W Ebert1, Maher A Dayeh2, Mihir Indrajit Desai2, Gang Li3 and Glenn M Mason4, (1)Southwest Research Institute San Antonio, San Antonio, TX, United States, (2)Southwest Research Institute, San Antonio, TX, United States, (3)University of Alabama in Huntsville, Huntsville, AL, United States, (4)JHU / APL, Laurel, MD, United States
Abstract:
Energetic storm particle (ESP) events are believed to occur as a result of diffusive shock acceleration at coronal mass ejection (CME)-driven interplanetary (IP) shocks. In situ observations of ESPs provide an excellent tool to study the physics of shock acceleration and the mechanisms that energize particles in events where the IP shock is remote (e.g. solar energetic particles – SEPs – that are accelerated in the solar corona). In this study, we use 1 AU observations during solar cycle 24 from ACE, STEREO-A, and STEREO-B during several ESP events observed at two or more spacecraft to examine the relationship between IP shocks and their associated energetic particles. Specifically, we examine the connection between variations in the properties of ~0.1 – 5 MeV/nucleon heavy ions (e.g. peak intensities, energy spectra, abundances) and IP shock parameters (e.g. shock obliquity, compression ratio, Mach number) that are observed at different points along the same CME-driven shock front. These results will be compared with theoretical predictions for heavy ion energy spectra and abundances in ESP events and could provide important additional constraints for particle acceleration in the inner heliosphere.
