HR: 1340h
AN: SM33A-0434    [Abstracts]
TI: A Survey of Phase Space Density Radial Distribution of Relativistic Electrons During a 2-year Time Period (2001-2002)
AU: * Chen, Y
EM: cheny@lanl.gov
AF: Los Alamos National Laboratory, PO Box 1663, MS D466, Los Alamos, NM 87545
AU: Reeves, G
EM: reeves@lanl.gov
AF: Los Alamos National Laboratory, PO Box 1663, MS D466, Los Alamos, NM 87545
AU: Friedel, R H
EM: friedel@lanl.gov
AF: Los Alamos National Laboratory, PO Box 1663, MS D466, Los Alamos, NM 87545
AB: The source of relativistic electrons in the Earth's radiation belts in recovery phase of geomagnetic storms is still an open question which requires more observational analysis. To address this question, we first need to differentiate between two competing mechanisms, inward radial transport or in-situ energization. Recent work has focused on analysis of phase space density distribution for specific storms of interest. Here we expand on the results of earlier event studies by surveying the phase space density radial distribution and its temporal evolution during storms for a time period of 2 years (2001-2002). Data in this work are from the IES and HIST electron detectors on board POLAR, whose orbit crosses the outer part of outer radiation belt through equatorial plane almost every 18 hours during this period. The fact that detected electrons with given 1st and 2nd adiabatic invariants can cover L*~6-10, allows tracing the temporally evolving radial gradient which can help in determining the source of new electrons. Initial analysis of approximately 190 days suggests that the energization of relativistic electrons may result from a more complicated combination of radial transport and in-situ acceleration than is usually assumed.
DE: 2720 Energetic particles: trapped
DE: 2730 Magnetosphere: inner
DE: 2774 Radiation belts
DE: 2788 Magnetic storms and substorms (7954)
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005