The Fermi-LAT Galactic Center Excess: From Precision Measurements to WIMP Interpretations
ABSTRACT
The origin of the Fermi-LAT Galactic Center excess remains one of the most debated questions in gamma-ray astrophysics.
I will present a new measurement of its spectrum and morphology based on an improved treatment of interstellar emission and point sources.
The excess is found to be highly significant, approximately spherical, and well described by a generalized Navarro--Frenk--White profile, while stellar-bulge templates do not reproduce its full radial extension.
I will then discuss the implications for dark matter, reviewing which WIMP models can simultaneously explain the excess and satisfy relic-density, direct-detection, and indirect-detection constraints.
Most scenarios are restricted to narrow resonant regions, with pseudoscalar and leptophilic mediators among the most promising possibilities.
