HR: 1340h
AN: SH13A-1131    [Abstracts]
TI: Coronal Hard X-ray Emission in Occulted Flares
AU: * Balciunaite, P
EM: balciunaite@ssl.berkeley.edu
AF: Space Sciences Lab, University of California, Berkeley, CA 94720
AU: Krucker, S
EM: krucker@ssl.berkeley.edu
AF: Space Sciences Lab, University of California, Berkeley, CA 94720
AU: Lin, R P
EM: rlin@ssl.berkeley.edu
AF: Space Sciences Lab, University of California, Berkeley, CA 94720
AU: Lin, R P
EM: rlin@ssl.berkeley.edu
AF: Department of Physics, University of California, Berkeley, CA 94720
AB: We use RHESSI to investigate coronal sources in six behind-the-limb flares with occulted or partially occulted footpoints. The major findings are as follows: (1) Coronal hard X-ray ($>$ 20 keV) emission is observed above thermal soft X-ray ($<$ 12 keV) and EUV (195 $\AA$) emission (which confirms Masuda's above-the-loop-top source); (2) Coronal HXR sources show impulsive (on a scale of tens of seconds) variation in their HXR time profiles; (3) The data can be fitted with a power law component with an index of 5 to 7 or with several thermal components with very high temperatures up to 100 MK. Presently, using the derived physical parameters, we test various heating models to determine whether the coronal HXR emission is thermal or non-thermal.
DE: 7509 Corona
DE: 7519 Flares
DE: 7554 X rays, gamma rays, and neutrinos
DE: 7594 Instruments and techniques
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2004 AGU Fall Meeting