HR: 14:00h
AN: SM53A-01 [Abstracts]
TI: Eigenmode Analysis of Pitch-Angle Diffusion of Energetic Electrons in the Outer Zone
AU: * O'Brien, T P
EM: paul.obrien@aero.org
AF: The Aerospace Corporation, 15049 Conference Center Drive
CH3/210, Chantilly, VA 20151, United States
AU: Shprits, Y Y
EM: yshprits@atmos.ucla.edu
AF: UCLA, 7984 Math Sciences Bldg
405 Hilgard Ave, Los Angeles, CA 90095-1565, United States
AB:
We determine the eigenfunctions and eigenvalues of the pitch-angle
diffusion operator predicted by quasilinear diffusion theory and
approximate plasma wave parameters for energetic electrons in the
outer zone. We consider scattering alone and in concert from three
wave populations: hiss, chorus, and EMIC. By projecting ptich-angle
distributions observed by CRRES into the eigenfunctions, we can
determine whether the pitch-angle distributions are consistent with
the assumed diffusion process. Eigenmodes with shorter decay times
(i.e., larger negative eigenvalues) ought to represent a comparatively
smaller portion of the total flux in the pitch angle distribution. We
use this technique to compare quiet-time and storm-time pitch-angle
distributions, and to infer the relative contribution of different
waves to the angular diffusion during those times.
DE: 2720 Energetic particles: trapped
DE: 2774 Radiation belts
DE: 7857 Stochastic phenomena (3235, 3265, 4475)
DE: 7867 Wave/particle interactions (2483, 6984)
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Joint Assembly