Search for hig energy solar flares with Fermi-LAT

TL;DR

This paper details the search for high energy gamma-ray emissions from solar flares using Fermi-LAT data, providing preliminary upper limits and analysis techniques during solar cycle 24.

Contribution

It introduces new analysis methods and reports initial upper limits on solar flare gamma-ray emissions at energies above 100 MeV.

Findings

Preliminary upper limits on solar flare gamma-ray emission established.

Analysis techniques for high energy solar flare detection described.

No significant high energy solar flare emission detected so far.

Abstract

The Fermi Large Area Telescope (LAT) has been surveying the sky in gamma rays from 30 MeV to more than 300 GeV since August 2008. Fermi is the only mission able to detect high energy > few hundreds MeV emission from the Sun during the new solar cycle 24: the Solar System Science Group of the Fermi team is continuously monitoring high energy emission from the Sun searching for flare events. Preliminary upper limits (E>100 MeV) have been derived for all solar flares detected so far by other missions and experiments (RHESSI, Fermi, GBM, GOES). Upper limit for flaring Sun emission (integrated over one year of data) has also been derived. Here we present the analysis techniques as well as the details of this search and the preliminary results obtained so far.