HR: 14:00h
AN: SH33A-03 [Abstracts]
TI: Solar Electron Bursts Observed Below 1.4 keV by ACE and Genesis: Characteristics and Implications for Particle Transport
AU: * de Koning, C A
EM: dekoning@lanl.gov
AF: Los Alamos National Laboratory, Space Sciences and Applications
Mail Stop D466, Los Alamos, NM 87545 United States
AU: Steinberg, J T
EM: jsteinberg@lanl.gov
AF: Los Alamos National Laboratory, Space Sciences and Applications
Mail Stop D466, Los Alamos, NM 87545 United States
AU: Skoug, R M
EM: rskoug@lanl.gov
AF: Los Alamos National Laboratory, Space Sciences and Applications
Mail Stop D466, Los Alamos, NM 87545 United States
AU: Gosling, J T
EM: jgosling@lanl.gov
AF: Los Alamos National Laboratory, Space Sciences and Applications
Mail Stop D466, Los Alamos, NM 87545 United States
AB:
Solar active processes frequently produce electron bursts at energies below 1.4 keV. The characteristics of these solar
electron bursts vary considerably from event to event due to the physical processes
involved in their acceleration and propagation to Earth. Previous
observations have shown that some bursts have a broader pitch-angle
distribution than the preceding strahl distribution, suggesting that
propagation effects are important for understanding 1 AU
observations.
We present a study of the pitch-angle distributions of suprathermal
electrons observed by ACE and Genesis before, during, and after solar
bursts. We report the fraction of burst beams that broaden, the
conditions under which they broaden, and the energy dependence of the
burst beam width. We find that most long duration, high intensity
bursts broaden. We often find a delay in the onset of
burst beam broadening relative to the burst onset.
The fact that some bursts broaden relative to the preceding strahl
suggests that broadening occurs by a self-generated process. The facts
that high intensity bursts broaden preferentially and that broadening
is delayed suggest that this process has a threshold level.
DE: 2118 Energetic particles, solar
DE: 7514 Energetic particles (2114)
DE: 7807 Charged particle motion and acceleration
DE: 7859 Transport processes
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2005 Joint Assembly