Analysis of a non-storm time enhancement in outer belt electrons

Tuesday, 16 December 2014
Quintin Schiller1, Xinlin Li1, Humberto C Godinez2, Theodore E Sarris3, Weichao Tu4, David Malaspina5, Drew L Turner6, J. B. Blake7 and Josef Koller2, (1)University of Colorado at Boulder, Boulder, CO, United States, (2)Los Alamos National Lab, Los Alamos, NM, United States, (3)Demokritus University of Thrace, Xanthi, Greece, (4)Los Alamos National Laboratory, Los Alamos, NM, United States, (5)University of Colorado, Boulder, Laboratory for Atmospheric and Space Physics, Boulder, CO, United States, (6)University of California Los Angeles, Los Angeles, CA, United States, (7)The Aerospace Corporation, Los Angeles, CA, United States
A high-speed solar wind stream impacted Earth’s magnetosphere on January 13th, 2013, and is associated with a large enhancement (>2.5 orders) of outer radiation belt electron fluxes despite a small Dst signature (-30 nT). Fortunately, the outer belt was well sampled by a variety of missions during the event, including the Van Allen Probes, THEMIS, and the Colorado Student Space Weather Experiment (CSSWE). In-situ flux and phase space density observations are used from MagEIS (Magnetic Electron Ion Spectrometer) onboard the Van Allen Probes, REPTile (Relativistic Electron and Proton Telescope integrated little experiment) onboard CSSWE, and SST onboard THEMIS. The observations show a rapid increase in 100’s keV electron fluxes, followed by a more gradual enhancement of the MeV energies. The 100’s keV enhancement is associated with a substorm injection, and the futher energization to MeV energies is associated with wave activity as measured by the Van Allen Probes and THEMIS. Furthermore, the phase space density radial profiles show an acceleration region occurring between 5<L*<6. We investigate the relationship between the substorm-injected seed population, wave activity, and the electron acceleration region. Specifically, a one dimensional data assimilation algorithm is used to reconstruct the phase space density radial profile. The algorithm also estimates electron source rate parameters, which are compared with the radial location of the seed population and to the intensity and radial extent of wave activity.