HR: 17:10h
AN: SH54A-03    [Abstracts]
TI: Antiprotons in the radiation belt
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
EM: mark.d.looper@aero.org
AF: The Aerospace Corporation, P.O. Box 92957, Los Angeles, CA 90009, United States
AU: * Mewaldt, R A
EM: rmewaldt@srl.caltech.edu
AF: California Institute of Technology, MC 220-47, Pasadena, CA 91125, United States
AU: Labrador, A W
EM: labrador@srl.caltech.edu
AF: California Institute of Technology, MC 220-47, Pasadena, CA 91125, United States
AB: The main source of antiprotons for Earth's radiation belt is decay of albedo antineutrons formed by interactions of cosmic rays with the atmosphere. This is analogous to the CRAND (cosmic ray albedo neutron decay) process that is the main source of high-energy (>100~MeV) radiation belt protons. We describe the intensity and spatial distribution of both the antiproton and proton components based on numerical simulation of the inner radiation belt. The albedo process is modeled using Geant4, a Monte Carlo nuclear transport code. Other model inputs to the simulation include the galactic cosmic ray intensity, atmospheric densities, the geomagnetic field, the radial (cross-L) diffusion coefficient, cross sections for trapped particle losses due to inelastic nuclear processes including annihilation, and rates of energy loss to ionization of the atmosphere. The resulting antiproton intensity is compared to that from other sources.
DE: 2720 Energetic particles: trapped
DE: 2730 Magnetosphere: inner
DE: 2774 Radiation belts
DE: 7959 Models
DE: 7984 Space radiation environment
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2007 Joint Assembly