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RHESSI observation of flare elements

Paolo C. Grigis·Arnold O. Benz
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Abstract

RHESSI observations of elementary flare bursts are presented. These solar flare elements are distinct emission peaks of a duration of some tens of seconds present in the hard X-ray light curves. They are characterized by consistent soft-hard-soft spectral behavior, which can be described in a quantitative way and compared which predictions from acceleration models. A detailed analysis of hard X-ray images for an M5 class flare shows that elementary flare bursts do not occur at distinct locations, but as twin X-ray sources move smoothly along an arcade of magnetic loops. This observation apparently contradicts the predictions of standard translation invariant 2.5-dimensional reconnection models.

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Paolo C. Grigis, Arnold O. Benz. 2006-02-14. RHESSI observation of flare elements. https://arxiv.org/abs/astro-ph/0602302

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