HR: 1340h
AN: SM13A-1203    [Abstracts]
TI: Radial Diffusion Modeling with Data Derived Effective Lifetimes: Losses Inside and Outside Plasmasphere
AU: * Shprits, Y Y
EM: yshprits@atmos.ucla.edu
AF: University of California, Los Angeles Department of Atmospheric and Oceanic Sciences, 405 Hilgard Ave Box 951565 7127 Math Sciences Bldg. , Los Angeles, CA 90095-1565 United States
AU: Thorne, R M
EM: rmt@atmos.ucla.edu
AF: University of California, Los Angeles Department of Atmospheric and Oceanic Sciences, 405 Hilgard Ave Box 951565 7127 Math Sciences Bldg. , Los Angeles, CA 90095-1565 United States
AU: Reeves, G D
EM: reeves@lanl.gov
AF: Los Alamos National Laboratory, MS D466 LANL , Los Alamos, NM 87545 United States
AU: Friedel, R
EM: friedel@lanl.giv
AF: Los Alamos National Laboratory, MS D466 LANL , Los Alamos, NM 87545 United States
AB: We attempted to quantify the competing effects of inward radial diffusion and losses inside and outside plasmasphere on the distribution of the outer zone electrons with a time dependent radial diffusion model. We present a detailed analysis of individual storms as well as comparison of data and model for 500 CRRES orbits. The rate of radial diffusion has been parameterized by the Kp with the loss time as an adjustable parameter. We find that plasmapause is a boundary between rapid and moderate losses. 1.0 MeV electron lifetimes are less then 1/2 day during the storm main phase and 3 days under quiet conditions, consistent with current estimates of the storm time loss rate [Albert, 2003; Summers and Thorne, 2003; O'Brien et al., 2003] and also provide an acceptable representation of electron decay rates following the storm time injection. We find that a radial diffusion source alone with data derived effective lifetimes approximately reproduces the amplitude and spatial distribution of outer zone fluxes, but fails to reproduce the gradual build up of fluxes observed for many storms as well as depletions of the radiation belts during the main phase of the storm. This suggests the need to include the local acceleration source as well as local loss which could be estimated from the comparison of the model results with fluxes derived in terms of Roederer L* using various field models .
DE: 2716 Energetic particles, precipitating
DE: 2720 Energetic particles, trapped
DE: 2753 Numerical modeling
DE: 2768 Plasmasphere
DE: 2788 Storms and substorms
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting