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arXiv · 1512.02237

Particle Acceleration by a Solar Flare Termination Shock

Bin Chen·Timothy S. Bastian·Chengcai Shen·Dale E. Gary·Sam Krucker·Lindsay Glesener
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Abstract

Solar flares - the most powerful explosions in the solar system - are also efficient particle accelerators, capable of energizing a large number of charged particles to relativistic speeds. A termination shock is often invoked in the standard model of solar flares as a possible driver for particle acceleration, yet its existence and role have remained controversial. We present observations of a solar flare termination shock and trace its morphology and dynamics using high-cadence radio imaging spectroscopy. We show that a disruption of the shock coincides with an abrupt reduction of the energetic electron population. The observed properties of the shock are well-reproduced by simulations. These results strongly suggest that a termination shock is responsible, at least in part, for accelerating energetic electrons in solar flares.

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Bin Chen, Timothy S. Bastian, Chengcai Shen, Dale E. Gary, Sam Krucker, Lindsay Glesener. 2015-12-07. Particle Acceleration by a Solar Flare Termination Shock. https://doi.org/10.1126/science.aac8467

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