Physics (Internal)

The Fermi GeV excess: annihilating dark matter or millisecond pulsars?

This event is part of the HET Seminar Series.

Abstract: Data from the Fermi Large Area Telescope suggests that there is an extended excess of GeV gamma-ray photons in the Inner Galaxy. Identifying potential astrophysical sources that contribute to this excess is an important step in verifying whether the signal originates from annihilating dark matter. I will show that the statistics of the photons---in particular, the flux probability density function of the photon counts below the point-source detection threshold---can potentially distinguish between the dark-matter and point-source interpretations of the excess. I will describe preliminary results that arise from applying our statistical method to the Fermi data.