THE FORMATION OF KAPPA-DISTRIBUTION ACCELERATED ELECTRON POPULATIONS IN SOLAR FLARES
نویسندگان
چکیده
منابع مشابه
Kappa distribution and hard X - ray emission of solar flares
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 spectru...
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Although both electron-ion and electron-electron bremsstrahlung contribute to the hard Xray emission from solar flares, the latter is normally ignored. Such an omission is not justified at electron (and photon) energies above ∼ 300 keV, and inclusion of the additional electron-electron bremsstrahlung in general makes the electron spectrum required to produce a given hard X-ray spectrum steeper ...
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Context. Stochastic acceleration is thought to be a key mechanism in the energization of solar flare electrons. Aims. We study whether stochastic acceleration can reproduce the observed soft-hard-soft evolution of the spectral features of the hard X-ray emitted by suprathermal electrons. We pay special attention to the effects of particle trapping and escape. Methods. The Fokker-Planck equation...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2014
ISSN: 1538-4357
DOI: 10.1088/0004-637x/796/2/142