HR: 10:20h
AN: SM42A-01 INVITED [Abstracts]
TI: Relativistic Electron Acceleration by ULF and VLF waves: A comparative study
AU: * OBrien, P
EM: paul.obrien@aero.org
AF: The Aerospace Corporation, 15049 Conference Center Drive, CH3/210, Chantilly, Va 20151
United States
AB:
Vigorous research over the past several years has narrowed the search
for acceleration mechanisms for outer zone MeV electrons to two main
candidates: enhanced diffusive radial transport by ULF waves and local
stochastic acceleration by VLF waves. Because the drivers of both
potential acceleration mechanisms are enhanced during magnetic storms,
it is difficult, from correlation analyses alone, to determine which
of the two mechanisms is most relevant at each L shell. Further
complicating matters is the enormous challenge of comprehensively
measuring the relevant wave spectra in space, frequency, and wave
number (k-vector). Nonetheless, a combination of empirical and
theoretical arguments allows us to construct a working hypothesis of
dual acceleration, with VLF waves being the likely mechanism at lower
L shells and ULF waves being the likely mechanism at higher L
shells. The presentation concludes with suggestions for future
analyses that might better delineate the two mechanisms.
DE: 2720 Energetic particles: trapped
DE: 2730 Magnetosphere: inner
DE: 2774 Radiation belts
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005