Broad Line Radio Galaxies Observed with Fermi-LAT: The Origin of the GeV Gamma-Ray Emission

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We report on a detailed investigation of the gamma-ray emission from 18 broad line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope (LAT) data.

• We confirm the previously reported detections of 3C 120 and 3C 111 in the GeV photon energy range; a detailed look at the temporal characteristics of the observed gamma-ray emission reveals in addition possible flux variability in both sources.
• No statistically significant gamma-ray detection of the other BLRGs was however found in the considered dataset.
• Though the sample size studied is small, what appears to differentiate 3C 111 and 3C 120 from the BLRGs not yet detected in gamma-rays is the particularly strong nuclear radio flux.