HR: 0800h
AN: SM21A-0329    [Abstracts]
TI: Parameterization of radiation belt electron loss timescales due to interactions with chorus waves
AU: * Shprits, Y Y
EM: yshprits@atmos.ucla.edu
AF: UCLA, UCLA Department of Atmospheric and Oceanic Sciences 7232 Math Sciences Los Angeles, CA 90095-1565, Los Angeles, CA 90024, United States
AU: Thorne, R
EM: rmt@atmos.ucla.edu
AF: UCLA, UCLA Department of Atmospheric and Oceanic Sciences 7232 Math Sciences Los Angeles, CA 90095-1565, Los Angeles, CA 90024, United States
AU: Meredith, N
EM: nmer@bas.ac.uk
AF: BAS, Natural Environment Research Council, High Cross, Madingley Road, United Kingdom, Cambridge, CB3 0ET, United Kingdom
AB: In this study parameterizations for the loss of the radiation belt electrons to the atmosphere due to the resonant pitch-angle scattering by chorus waves are developed. By analyzing the dependence of the loss rates on L-value and energy we find dependencies for the lifetime of the radiation belt electrons. Parameters of the functional dependences are obtained using a linear regression technique. To create parameterizations of loss rate as a function of geomagnetic indices, we also analyzed the statistical data from day-side lower band chorus observations in the range of geomagnetic latitudes from 20œ to 30œ. The combined parameterizations of the wave amplitudes and scattering rates indicate that electron loss due to chorus waves strongly depends on energy and geomagnetic activity. During storm-time conditions the lifetimes of relativistic electrons, in the heart of the outer zone are on the order of a day and are on the scale of hours at lower energies. The developed parameterizations may be used in particle tracing codes and radial diffusion codes.
DE: 2716 Energetic particles: precipitating
DE: 2720 Energetic particles: trapped
DE: 2730 Magnetosphere: inner
DE: 2753 Numerical modeling
DE: 2774 Radiation belts
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting