HR: 1340h
AN: SH13A-1130 [Abstracts]
TI: Spectra of Solar Energetic Electrons in Flares and near Earth
AU: * Kontar, E P
EM: eduard@astro.gla.ac.uk
AF: Univserity of Glasgow, The Kelvin Building, Glasgow, G12Q88
United Kingdom
AU: Krucker, S
EM: krucker@ssl.berkeley.edu
AF: Space Sciences Lab
UC Berkeley, 7 Gauss Way, Berkeley, CA 94720-7450
United States
AU: Lin, R P
EM: rlin@ssl.berkelely.edu
AF: Space Sciences Lab
UC Berkeley, 7 Gauss Way, Berkeley, CA 94720-7450
United States
AB:
Successful operation of Reuven Ramaty High Energy Solar Spectroscopic
Imager (RHESSI) allows us to observe hard X-ray spectrum of many solar
flares with unprecendent energy resolution. X-ray spectra provide
us with vital information about the spectral properties of highly
energetic electrons at the Sun. The mean electron spectrum of the solar
flare can be recovered through a newly developed constraint regularization
analysis of the bremsstrahlung photon spectra that energetic electrons
produce. We emphasize the use of non-square inversion techniques combined
with the correction of the observed spectrum for the effect of Compton
photon back-scatter to achieve the most meaningful solution to the problem.
For 16 solar flares the electron spectrum of temporally related solar
energetic electron events has been measured using WIND/3DP allowing us
simultaneous analysis of electron flux spectral properties at the Sun
and near the Earth. Electron spectra from solar flares
show strong correlations with the spectrum of solar energetic
electrons, though vary with energy. Weaker correlation at lower energies
can be viewed as a propogation and/or escape effect.
Results suggest that the commonly used model of a collisional transport
(thick-target) for flare electrons plus free streaming for interplanetary
particles cannot explain the observed spectra.
DE: 7514 Energetic particles (2114)
DE: 7519 Flares
DE: 7554 X rays, gamma rays, and neutrinos
DE: 2114 Energetic particles, heliospheric (7514)
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting