Internal Bremsstrahlung Signature of Real Scalar Dark Matter and Consistency with Thermal Relic Density

Understand

A gamma-ray excess from the galactic center consistent with line emission around 130 GeV was recently found in the Fermi-LAT data.

• Although the Fermi-LAT Collaboration has not confirmed its significance, such a signal would be a clear signature of Dark Matter annihilation.
• Until now, there have been many attempts to explain the excess by Dark Matter.
• However these efforts tend to give too-small cross sections into photons if consistency with the correct thermal relic density of Dark Matter is required.