HR: 14:40h
AN: SM33B-05    [Abstracts]
TI: Modeling the Inner Radiation Belt Protons
AU: * Selesnick, R S
EM: Richard.S.Selesnick@aero.org
AF: The Aerospace Corporation, P.O. Box 92957, Los Angeles, CA 90009 United States
AU: Looper, M D
AF: The Aerospace Corporation, P.O. Box 92957, Los Angeles, CA 90009 United States
AU: Mewaldt, R A
AF: California Institute of Technology, MC 220-47, Pasadena, CA 91125 United States
AB: The main sources of energetic protons for the inner zone of the radiation belt are CRAND (cosmic ray albedo neutron decay) and inward diffusion of solar protons. In the absence of detailed measurements from the inner zone, a theoretical model can be of practical value in specifying the CRAND proton intensity, which is the dominant component at the higher trapped proton energies. Calculations done in the 1960s and '70s verified that CRAND can be a significant proton source. With updated model inputs and modern computers we now have the potential to calculate accurate intensities as a function of the three adiabatic invariants of trapped particle motion and of solar cycle phase. Significant aspects of the modeling include: calculation of the albedo neutron flux from models of the galactic cosmic rays and neutral atmosphere, drift averaging of the neutron decay source and the atmospheric densities, numerical calculation of adiabatic trapping limits in the geomagnetic field, and integration of the model transport equation with time and energy dependence. Preliminary results from such a modeling program will be described and compared to empirical radiation belt models.
DE: 2720 Energetic particles, trapped
DE: 2730 Magnetosphere--inner
DE: 2753 Numerical modeling
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting