Mr. Stephen Portillo (Harvard-Smithsonian Center for Astrophysics)
A highly significant and spatially extended excess of GeV gamma-rays has been observed by Fermi LAT in the Inner Galaxy. While the excess’s spectrum and morphology are consistent with a dark matter annihilation interpretation, the excess has also been interpreted to be the emission from a population of unresolved point sources. We present a Bayesian method for producing probabilistic catalogues to constrain the population of point sources below the Fermi LAT detection limit. To validate our method, we apply it to the high latitude Fermi LAT data and constrain the population of point sources down to 6×10-11 ph/cm2/s in 1-3 GeV, significantly below the 3FGL detection threshold ~2×10-10 ph/cm2/s. The probabilistic catalogue constrains the slope of the flux distribution of sources to be 1.8±0.2, agreeing with results obtained using non-Poissonian template fitting. The talk by Tansu Daylan will further present the probabilistic catalogue inferred using the Inner Galaxy Fermi LAT data.
Mr. Tansu Daylan (Graduate Student)