HR: 09:30h
AN: SM11B-06    [Abstracts]
TI: Influence of the thermal plasma distribution on relativistic electron loss during storm conditions
AU: * Thorne, R M
EM: rmt@atmos.ucla,edu
AF: Department of Atmospheric Sciences, University of California, Los Angeles, CA 90095 United States
AU: O'Brien, P
EM: paul.obrien@aero.org
AF: Space Science Department, The Aerospace Corporation, El Segundo, CA 90009 United States
AU: Summers, D
EM: dsummers@math.mun.ca
AF: Department of Mathematics and Statistics, Memorial University of Newfoundland, St. Jonh's, A1C 5S7 Canada
AU: Shprits, Y Y
EM: yshprits@atmos.ucla.edu
AF: Department of Atmospheric Sciences, University of California, Los Angeles, CA 90095 United States
AU: Horne, R B
EM: r.horne@bas.ac.uk
AF: British Antactic Survey, Madingley Road, Cambrigde, CB3 0ET United Kingdom
AB: Several distinct classes of plasma waves contribute to relativistic electron loss during storm conditions. Intense bursts of whistler-mode chorus resonate with relativistic electrons in the pre-noon sector at latitudes above 25 degrees leading to microburst precipitation. Such scattering can remove MeV electrons on timescales comparable to the storm duration (~ day). Night-side chorus is ineffective for MeV electron scattering due to the confinement of waves to latitudes below 15 degrees. Intense EMIC waves excited along the night-side plasmapause or within high-density drainage plumes in the post-noon sector can cause rapid loss of MeV electrons during the storm main phase. Since the effective timescale for loss to the atmosphere can be less than a day such waves are a prime candidate to explain observed flux depletions during the main phase of storms. Following the storm, as the plasmapause expands outwards to higher L, injected relativistic electrons can be slowly removed by scattering from plasmaspheric hiss on a timescale of 3-10 days. The distribution of thermal plasma controls such resonant wave-particle scattering and thus provides a natural coupling to the dynamics of the energetic electron population.
DE: 7867 Wave/particle interactions
DE: 2716 Energetic particles, precipitating
DE: 2720 Energetic particles, trapped
DE: 2730 Magnetosphere--inner
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting