HR: 0800h
AN: SM21A-0332    [Abstracts]
TI: Effects of off-diagonal terms and oblique wave propagation on calculations of radiation belt electron fluxes
AU: * Tao, X
EM: xtao@rice.edu
AF: Rice University, Department of Physics and Astronomy, MS 108 6100 Main Street, Houston, TX 77005-1892, United States
AU: Chan, A
EM: aac@rice.edu
AF: Rice University, Department of Physics and Astronomy, MS 108 6100 Main Street, Houston, TX 77005-1892, United States
AU: Albert, J
EM: jay.albert@hanscom.af.mil
AF: Air Force Research Laboratory, 29 Randolph Road, Hanscom AFB, MA 01731-3010, United States
AU: Miller, J
EM: millerja@uah.edu
AF: University of Alabama in Huntsville, Department of Physics 301 Sparkman Drive, Huntsville, AL 35899, United States
AB: Cyclotron-resonance interactions with whistler-mode chorus waves are thought to be an important mechanism for energizing electrons in the radiation belts. With a recently developed code, which uses Monte Carlo SDE (stochastic differential equation) methods to solve the bounce-averaged energy-pitch-angle quasilinear diffusion equation, we have investigated the effects of (i) ignoring off-diagonal diffusion terms, and (ii) assuming purely parallel-propagating waves. For diffusion coefficients corresponding to a model of storm-time chorus waves at L = 4.5, we find that at small pitch angles ignoring off-diagonal terms overestimates particle flux by as much as a factor of 2~5 for 0.5 MeV electrons, and by more than an order of magnitude for 2 MeV electrons. The parallel propagation assumption leads to errors of more than an order of magnitude in flux for both 0.5 MeV and 2 MeV electrons at some equatorial pitch-angles. For pitch angles near 90 degrees the effects of ignoring off- diagonal terms and oblique waves are relatively small, but overall these effects should be included to obtain more accurate particle fluxes.
DE: 2720 Energetic particles: trapped
DE: 2730 Magnetosphere: inner
DE: 2753 Numerical modeling
DE: 2774 Radiation belts
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting