Kappa distribution and hard X - ray emission of solar flares
نویسندگان
چکیده
Aims. We investigate whether the so-called kappa distribution, often used to fit electron distributions detected in-situ in solar wind, can describe electrons producing the hard X-ray emission in solar flares. Methods. Using Ramaty High Energy Solar Spectroscopic imager (RHESSI) flare data we fit spatially and feature integrated spectra assuming kappa distribution for mean electron flux spectrum. Results. We show that a single kappa distribution generally cannot describe spatially integrated X-ray emission composed both of footpoint and coronal sources. In contrast, the kappa distribution is consistent with mean electron spectra producing hard X-ray emission in some coronal sources.
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