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arXiv · 2507.08452

Ion acceleration in Fermi-LAT behind-the-limb solar flares: the role of coronal shock waves

Alexander Warmuth·Melissa Pesce-Rollins·Nicola Omodei·Song Tan
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Abstract

We investigate the relationship between the gamma-ray emission measured with Fermi-LAT and radio signatures of coronal shock waves in four behind-the-limb (BTL) solar flares. All events were associated with metric type II radio burst. Both start and end times of the radio bursts were synchronized with the gamma-ray emission. The type II bursts associated with the BTL gamma-ray flares had higher speeds and lower formation heights than those of an average sample. These findings support the notion that the highly relativistic ions that produce the gamma-rays in BTL flares are accelerated at CME-driven propagating coronal shock waves rather than in large-scale coronal loops.

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Alexander Warmuth, Melissa Pesce-Rollins, Nicola Omodei, Song Tan. 2025-07-11. Ion acceleration in Fermi-LAT behind-the-limb solar flares: the role of coronal shock waves. https://arxiv.org/abs/2507.08452

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