HR: 1330h
AN: SH22A-0171    [PDF]
TI: The Unusual Hard X-ray Spectrum of the Flare of 20 August 2002
AU: * Schwartz, R A
EM: richard.schwartz@gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 682, Greenbelt, md 20771 United States
AU: * Schwartz, R A
EM: richard.schwartz@gsfc.nasa.gov
AF: Science Systems and Applications Inc, 10210 Greenbelt Rd, suite 600, Lanham, md 20706 United States
AU: Kasparova, J
EM: kasparov@sunkl.asu.cas.cz
AF: Astronomical Institute, Academy of Sciences of the Czech Republic, Ondrejov, 111 Czech Republic
AU: Dennis, B
EM: brian.dennis@nasa.gov
AF: NASA Goddard Space Flight Center, Code 682, Greenbelt, md 20771 United States
AU: Karlicky, M
EM: karlicky@sunkl.asu.cas.cz
AF: Astronomical Institute, Academy of Sciences of the Czech Republic, Ondrejov, 111 Czech Republic
AB: An M3 Class flare was observed in x-rays with RHESSI and in H-alpha with the Kanzelhohe Solar Observatory. The event was observed to several hundreds of keV in X-rays and was marked by an unusually flat spectrum observed from 20-70 keV. The measured power-law exponent of this component was about 1.7, very close to the theoretical limit for a thick-target injection of energetic electrons implying a near cutoff below 80 keV. We will bound any systematic effects that may be contributing to this result by analyzing the spectrum using multiple techniques. We will also forward model the spatial/spectral x-ray sources to further validate these observations.
DE: 7509 Corona
DE: 7514 Energetic particles (2114)
DE: 7519 Flares
DE: 7554 X rays, gamma rays, and neutrinos
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting