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

2025/07/11 by Warmuth, Alexander, Pesce-Rollins, Melissa, Omodei, Nicola +1 · 1 citation
#FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE) #Solar and Stellar Astrophysics (astro-ph.SR)

paper · doi:10.48550/arxiv.2507.08452

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.

Citations

• Multispacecraft Observations of the 2024 September 9 Backside Solar Eruption that Resulted in a Sustained Gamma Ray Emission Event
• Implications of X-ray Observations for Electron Acceleration and Propagation in Solar Flares
• The Atmospheric Imaging Assembly (AIA) on the Solar Dynamics Observatory (SDO)

Cited by

• The impact of Solar magnetic field configurations on the production of gamma rays at the Solar disk

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