Flat-spectrum Radio Quasars and BL Lacs Dominate the Anisotropy of the Unresolved Gamma-Ray Background

Abstract We analyze the angular power spectrum (APS) of unresolved gamma-ray background (UGRB) emission and combine it with measured properties resolved sources Fermi-LAT 4FGL catalog. Our goals are to dissect composition sky establish relevance different classes source populations active galactic nuclei in determining observed size UGRB anisotropy, especially at low energies. find that, under physical assumptions for spectral energy distribution, i.e., by using catalog data as a prior, two required fit APS data, namely flat-spectrum radio quasars energies BL Lacs higher The inferred luminosity functions agree well extrapolation quasar Lac ones obtained from 4FLG use these calculate intensity blazars, finding contribution 20% 1 GeV 30% above 10 GeV. Finally, bounds on an additional due annihilating dark matter also derived.