Thermal and Nonthermal Contributions to the Solar Flare X-ray Flux

Title:

Thermal and Nonthermal Contributions to the Solar Flare X-ray Flux

Authors:

B. R. Dennis, K. J. H. Phillips, J. Sylwester, B. Sylwester, R. A. Schwartz, and K. A. Tolbert

Abstract:

The relative thermal and nonthermal contributions to the total energy budget of a solar flare are being determined through analysis of RHESSI X-ray imaging and spectral observations in the energy range from ~ 5 to ~ 50 keV. With its ~ 1-keV spectral resolution, intensities and equivalent widths of two line complexes, the Fe line group at 6.7 keV (mostly due to Fe XXV lines and Fe XXIV satellites) and the Fe/Ni line group at 8 keV (mostly due to higher-excitation Fe XXV lines and Ni XXVII lines) can be obtained as a function of time through a number of flares. With line and continuum intensities from the CHIANTI code, the thermal component of the flare emission can be more reliably separated from the nonthermal. The abundance of Fe can also be determined from RHESSI spectra. Comparisons of RHESSI spectra with those from the RESIK crystal spectrometer on CORONAS-F show very satisfactory agreement, giving much confidence in the intensity calibration of both instruments.

FULL VERSION-HTML
Get pdf (886)kb
Figures:	Figure1	Figure2
	Figure3	Figure3