HR: 1340h
AN: SM33A-0424 [Abstracts]
TI: Several Hundred keV electron precipitation measured by Korean satellite STSAT-1
AU: * Lee, J J
EM: jjlee@ssl.berkeley.edu
AF: Space Sciences Lab., University of California,Berkeley, 7 Gauss way, Berkeley, CA74720
United States
AU: Parks, G K
EM: parks@ssl.berkeley.edu
AF: Space Sciences Lab., University of California,Berkeley, 7 Gauss way, Berkeley, CA74720
United States
AU: Lee, E
EM: eslee@ssl.berkeley.edu
AF: Space Sciences Lab., University of California,Berkeley, 7 Gauss way, Berkeley, CA74720
United States
AU: McCarthy, M P
EM: mccarthy@geophys.washington.edu
AF: Geophysics Program, University of Washington, University of Washington, Seattle, WA98195
United States
AU: Min, K W
EM: kwmin@space.kaist.ac.kr
AF: Department of Physics, Korea Advanced Institute of Science and Technology, 373-1 Gusung-Dong Yousung-Gu,
Daejeon, 305-701
Korea, Republic of
AU: Kim, H
EM: woodcar@space.kaist.ac.kr
AF: Department of Physics, Korea Advanced Institute of Science and Technology, 373-1 Gusung-Dong Yousung-Gu,
Daejeon, 305-701
Korea, Republic of
AU: Park, J
EM: jhpark@space.kaist.ac.kr
AF: Department of Physics, Korea Advanced Institute of Science and Technology, 373-1 Gusung-Dong Yousung-Gu,
Daejeon, 305-701
Korea, Republic of
AU: Hwang, J
EM: jahwang@space.kaist.ac.kr
AF: Department of Physics, Korea Advanced Institute of Science and Technology, 373-1 Gusung-Dong Yousung-Gu,
Daejeon, 305-701
Korea, Republic of
AB:
In this presentation, we show two kinds of electron precipitations observed by the Korean satellite STSAT-1. One is
microburst that has very short duration of less than 1 second. Our observations show microburst energy spectra of
precipitated electrons inside the loss cone (precipitated) have higher e-folding energies during disturbed times than quiet
times. The loss cone at these energies is empty except when microbursts abruptly appear and fill the loss cone in less than
50 msec. This fast pitch angle diffusion requires diffusion coefficients be larger than ~3.5 ×10-2 rad2/sec,
while ~1.5 ×10-5 rad2/sec was proposed by Albert (2002). The other precipitation has long duration of a few
hours at the midnight trapping boundary. These events occur under quiet geomagnetic condition and display energy dispersion
in the low latitude boundary. We have modeled this precipitation form invoking pitch angle scattering in the field reversal
region where magnetic field significantly varies within a cyclotron radius and the first adiabatic invariant is not
conserved. Our observations show these two kinds of precipitation could be the dominant loss mechanism of relativistic
electrons in the radiation belt.
DE: 7807 Charged particle motion and acceleration
DE: 7867 Wave/particle interactions (2483, 6984)
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005