The principal results on active galactic nuclei from the Phase 1 observations by the COMPTON Gamma Ray Observatory are presented. These include the detection of a new class of high-energy gamma ray sources by the EGRET instrument and extensive observations of Seyfert galaxies in low-energy gamma rays by OSSE. The identified EGRET sources are associated with core-dominated radio loud objects, OVV's and BL Lacs. EGRET has not detected any Seyfert galaxies. OSSE observes a thermal-like spectrum from NGC 4151, and the low-energy gamma ray spectra of other Seyferts are significantly softer than the spectra below 50 keV, suggesting that a thermal emission mechanism is characteristic of these objects. OSSE has not detected any positron annihilation radiation from any Seyfert, and neither OSSE nor COMPTEL have detected an MeV excess from these sources.
The slope of the low-energy spectrum of prompt gamma-ray burst emission