Identification of the Early Fermi LAT Gamma-Ray Bright Objects with Extragalactic VLBI sources

Understand

A list of 205 gamma-ray strong objects was reported recently as a result of a 3-month integration with the Large Area Telescope on board the Fermi Gamma-Ray Space Telescope.

• We attempted identification of these objects, cross-correlating the gamma-ray positions with VLBI positions of a large all-sky sample of extragalactic radio sources selected on the basis of their parsec-scale flux density.
• The original associations reported by the Fermi team are confirmed and six new identifications are suggested.
• A Monte-Carlo analysis shows that the fraction of chance associations in our analysis is less than 5 per cent, and confirms that the vast majority of gamma-ray bright extragalactic sources are radio loud blazars with strong parsec-scale jets.