Millisecond pulsars in the galactic bulge? An extended discussion on the wavelet analysis of the fermi-LAT data

A clear excess in the Fermi-LAT data is present at energies around a few GeV. The spectrum of this so-called 'GeV excess' is remarkably similar to the expected annihilation signal of WIMP dark matter. However, a large bulge population of millisecond pulsars living below the Fermi-LAT detection threshold could also explain the excess spectrum. In a recent work we optimized the search for sub-threshold sources, by applying a wavelet transform to the Fermi-LAT gamma-ray data. In the Inner-Galaxy the wavelet signal is significantly enhanced, providing supportive evidence for the point source interpretation of the excess. In these proceedings we will extent our previous work with a spectral analysis and elaborate on the potential contamination from substructures in the gas.