Constraints on the Galactic Halo Dark Matter from Fermi-LAT Diffuse Measurements

TL;DR

This paper uses Fermi-LAT gamma-ray data to differentiate between astrophysical backgrounds and potential dark matter signals in the Galactic Halo, setting constraints on dark matter properties.

Contribution

It performs a comprehensive sky and spectral analysis to constrain dark matter annihilation and decay rates using Fermi-LAT data.

Findings

Constraints on dark matter annihilation cross section.

Limits on dark matter decay rate.

Analysis of spectral signatures of dark matter.

Abstract

The diffuse gamma ray emission from astrophysical backgrounds in our Galaxy and the signal due to the annihilation or decay of Dark Matter (DM) in the Galactic Halo are expected to have a substantially different morphology and spectral signatures. In order to exploit this feature we perform a full sky and spectral binned likelihood fit of both components, using data collected during the first 21 months of operation of the Fermi-LAT observatory. Preliminary constraints are presented on the DM annihilation cross section and decaying rate for various masses and annihilation/decay modes.