HR: 0830h
AN: SM41C-0588    [PDF]
TI: Phase Space Distribution of Relativistic Electrons at Geosynchronous Orbit
AU: * Chen, Y
EM: cheny@lanl.gov
AF: Space and Atmospheric Sciences, Los Alamos National Lab, PO Box 1663, MS D466, Los Alamos, NM 87545
AU: Reeves, G D
EM: reeves@lanl.gov
AF: Space and Atmospheric Sciences, Los Alamos National Lab, PO Box 1663, MS D466, Los Alamos, NM 87545
AU: Friedel, R H
EM: rfriedel@lanl.gov
AF: Space and Atmospheric Sciences, Los Alamos National Lab, PO Box 1663, MS D466, Los Alamos, NM 87545
AU: Taylor, M G
EM: mggtt@lanl.gov
AF: Space and Atmospheric Sciences, Los Alamos National Lab, PO Box 1663, MS D466, Los Alamos, NM 87545
AU: Dors, E E
EM: edors@lanl.gov
AF: Space and Atmospheric Sciences, Los Alamos National Lab, PO Box 1663, MS D466, Los Alamos, NM 87545
AU: Thomsen, M F
EM: mthomsen@lanl.gov
AF: Space and Atmospheric Sciences, Los Alamos National Lab, PO Box 1663, MS D466, Los Alamos, NM 87545
AU: Onsager, T G
EM: terry.onsager@noaa.gov
AF: NOAA Space Environment Center, 325 Broadway, Boulder, CO 80305
AU: Chan, A A
EM: anthony-chan@rice.edu
AF: Department of Physics and Astronomy, Rice University, 6100 Main St., MS108, Houston, TX 77005
AB: Understanding the behavior of relativistic electrons in the Earth's radiation belts is of great significance for both practical and theoretical reasons. Although many models have been developed to describe the acceleration, transportation and loss processes, the differentiation of those competing theories eventually calls for a data-assimilation based global electron phase space density model. As an initial step in this development we present the relativistic electron phase space density distribution in the vicinity of geostationary orbit. Combining data from the LANL geosynchronous SOPA and ESP instruments with data from the GOES satellites provides up to 8 simultaneous measurements distributed in longitude. Because of the tilt of the magnetic equator with respect to the geographic equator and drift shell splitting for different pitch angles each satellite samples a different range of L* throughout its orbit. We use a storm-time magnetic field model and the measured pitch-angle resolved electron spectra to determine the phase space density as a function of fixed adiabatic invariants at each spacecraft. Comparing all satellite measurements provides a determination of the global phase space density gradient over the range L*~6-7 as a function of both universal time and local time. We also describe methods for simultaneously solving the field model and particle distributions as a next step toward a global data-assimilation based radiation belt model.
DE: 2700 MAGNETOSPHERIC PHYSICS
DE: 2720 Energetic particles, trapped
DE: 2730 Magnetosphere--inner
DE: 2784 Solar wind/magnetosphere interactions
DE: 7807 Charged particle motion and acceleration
SC: SPA - Magnetospheric Physics [SM]
MN: 2003 Fall Meeting