Tentative observation of a gamma-ray line at the Fermi LAT

TL;DR

This paper reports a tentative gamma-ray line at 130 GeV near the Galactic center observed with Fermi LAT, suggesting potential dark matter annihilation signals with moderate statistical significance.

Contribution

It presents the first evidence of a gamma-ray line at 130 GeV, analyzing Fermi LAT data and discussing possible dark matter implications and instrumental effects.

Findings

4.6 sigma excess near Galactic center at 130 GeV

Significance reduces to 3.2 sigma after look-elsewhere correction

Implication of dark matter particles with mass around 130 GeV

Abstract

Using 43 months of public gamma-ray data from the Fermi Large Area Telescope, we find in regions close to the Galactic center at energies of 130 GeV a 4.6 sigma excess that is not inconsistent with a gamma-ray line from dark matter annihilation. When taking into account the look-elsewhere effect, the significance of the observed signature is 3.2 sigma. If interpreted in terms of dark matter particles annihilating into a photon pair, the observations imply a partial annihilation cross-section of about 10^-27 cm^3s^-1 and a dark matter mass around 130 GeV. We review aspects of the statistical analysis and comment on possible instrumental indications.