The blazar gamma-ray luminosity function and the diffuse extragalactic gamma-ray background

We have used the data from the new EGRET catalog on "grazars" (blazars which are observed to be high-energy γ-ray sources), together with radio data, to construct a new relation between radio and γ-ray luminosity for these sources. Using this relation to construct a grazar γ-ray luminosity function, we then calculate the contribution of unresolved grazars to the cosmic γ-ray background radiation. We derive the energy spectrum of this background component above 100 MeV and the angular fluctuations in this background implied by our model.