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arXiv · 0710.0757

The Cause of Photospheric and Helioseismic Responses to Solar Flares: High-Energy Electrons or Protons?

A. G. Kosovichev
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Abstract

Analysis of the hydrodynamic and helioseismic effects in the photosphere during the solar flare of July 23, 2002, observed by Michelson Doppler Imager (MDI) on SOHO, and high-energy images from RHESSI shows that these effects are closely associated with sources of the hard X-ray emission, and that there are no such effects in the centroid region of the flare gamma-ray emission. These results demonstrate that contrary to expectations the hydrodynamic and helioseismic responses (''sunquakes") are more likely to be caused by accelerated electrons than by high-energy protons. A series of multiple impulses of high-energy electrons forms a hydrodynamic source moving in the photosphere with a supersonic speed. The moving source plays a critical role in the formation of the anisotropic wave front of sunquakes.

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A. G. Kosovichev. 2007-10-03. The Cause of Photospheric and Helioseismic Responses to Solar Flares: High-Energy Electrons or Protons?. https://doi.org/10.1086/524036

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