HR: 0830h
AN: SM41C-0585    [PDF]
TI: Low Altitude Distribution of Radiation Belt Electrons
AU: * Selesnick, R S
EM: richard.s.selesnick@aero.org
AF: The Aerospace Corp., P.O. Box 92957 - M2/259, Los Angeles, CA 90009-2957 United States
AB: In radiation belt mapping it is usual to assume that particle data are independent of the phase angles associated with gyration, bounce, and drift motions. Similarly, trapped particle modeling often addresses the bounce and drift averaged distribution of the guiding centers. These are useful approximations for the high altitude radiation belt, where most of the observed particles have mirror points that are well above the dense atmosphere. The reverse is true at low altitudes (below $\sim$1000~km) where it becomes necessary to account for the role of the atmosphere in creating strong bounce and drift phase dependences of the trapped particle guiding center distributions. Such a computational model of the low altitude electron distribution is described. It applies to geomagnetically quiet periods of decaying electron intensity and to locations inside the plasmasphere where plasma waves are the dominant scattering mechanism that cause diffusion into the atmospheric loss cones. The model parameters are adjusted to fit samples of electron data taken by a low altitude satellite, thereby providing empirical constraints on theories of radiation belt electron losses.
DE: 2716 Energetic particles, precipitating
DE: 2720 Energetic particles, trapped
DE: 2730 Magnetosphere--inner
DE: 2753 Numerical modeling
SC: SPA - Magnetospheric Physics [SM]
MN: 2003 Fall Meeting