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arXiv · 1111.7026

Fermi Detection of \gamma-ray emission from the M2 Soft X-ray Flare on 2010 June 12

Fermi GBM Collaboration·Fermi LAT Collaboration·B. R. Dennis·R. A. Schwartz·A. K. Tolbert
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Abstract

The GOES M2-class solar flare, SOL2010-06-12T00:57, was modest in many respects yet exhibited remarkable acceleration of energetic particles. The flare produced an ~50 s impulsive burst of hard X- and \gamma-ray emission up to at least 400 MeV observed by the Fermi GBM and LAT experiments. The remarkably similar hard X-ray and high-energy \gamma-ray time profiles suggest that most of the particles were accelerated to energies >300 MeV with a delay of ~10 s from mildly relativistic electrons, but some reached these energies in as little as ~3 s. The \gamma-ray line fluence from this flare was about ten times higher than that typically observed from this modest GOES class of X-ray flare. There is no evidence for time-extended >100 MeV emission as has been found for other flares with high-energy \gamma rays.

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Fermi GBM Collaboration, Fermi LAT Collaboration, B. R. Dennis, R. A. Schwartz, A. K. Tolbert. 2011-11-30. Fermi Detection of \gamma-ray emission from the M2 Soft X-ray Flare on 2010 June 12. https://doi.org/10.1088/0004-637x/745/2/144

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