Shedding new light on the Sun with the Fermi LAT

TL;DR

The paper reviews six years of Fermi LAT observations of solar flares, revealing new insights into high-energy gamma-ray emissions, including behind-the-limb events, and discusses their implications for understanding particle acceleration.

Contribution

It provides the first comprehensive overview of solar flare detections by Fermi LAT, highlighting novel observations such as behind-the-limb gamma-ray emissions.

Findings

Detected over 40 solar flares with >30 MeV gamma-ray emission.

Observed gamma-ray emissions lasting up to 20 hours.

Identified gamma-ray emissions from flares behind the limb.

Abstract

During its first six years of operation, the Fermi Large Area Telescope (LAT) has detected >30 MeV gamma-ray emission from more than 40 solar flares, nearly a factor of 10 more than those detected by EGRET. These include detections of impulsive and sustained emissions, extending up to 20 hours in the case of the 2012 March 7 X-class flares. We will present an overview of solar flare detections with LAT, highlighting recent results and surprising features, including the detection of >100 MeV emission associated with flares located behind the limb. Such flares may shed new light on the relationship between the sites of particle acceleration and gamma-ray emission.