Characteristics of galactic gamma-ray sources in the second EGRET catalog

The second catalog of high-energy gamma-ray sources (> 100 MeV) has been derived from the EGRET all sky survey (Phase 1) and the pointed observations obtained during Phase 2 of the Compton Observatory mission. This catalog uses not only more data but also an improved model of the diffuse galactic gamma-ray background which is essential for the analysis of point sources. 129 sources were detected. They include identified sources (a solar flare, five pulsars, the Large Magellanic Cloud and 51 active galactic nuclei, AGN) as well as sources for which no identification with objects at other wavelengths is yet available. We present a short summary of the 2EG catalog and derive properties of the low galactic latitude population of unidentified gamma-ray sources based on assumptions on their distribution in the Galaxy. The typical luminosity of galactic unidentified sources above 100 MeV must be in the range 6 10(34) to 4 10(35) erg/s in order to be compatible with their observed spatial galactic distribution and the spectrum of their fluxes.