http://arxiv.org/abs/1905.10771
A preliminary version of the fourth catalog (4LAC) of active galactic nuclei (AGNs) detected by the Fermi-Large Area Telescope (LAT) is presented. It is based on the fourth Fermi-LAT catalog (4FGL) of sources detected with a Test Statistic (TS) greater than 25 between 50 MeV and 1 TeV using the first 8 years of gamma-ray data. The 4LAC catalog includes 2863 AGNs located at high Galactic latitudes (|b|>10{\deg}), a 80% increase over the previous 3LAC catalog established with 4 years of data. AGNs represent at least 79% of the high-latitude 4FGL sources. In addition, we report the detection of 345 AGNs located at low galactic latitudes. A fraction of 98% of the detected AGNs are blazars. These blazars are classified following a two-fold approach i) according to the strength of their optical lines as Flat Spectrum Radio Quasars, FSRQs, BL Lac-type objects, BL Lacs, or blazar candidates of unknown types, BCUs and ii) according to the position of their synchrotron peak, using archival data as low-, intermediate- or high-synchrotron peaked objects, LSPs, ISPS and HSPs respectively. The properties of these sources, in terms of spectral features, redshifts and variability, are briefly discussed.
F. collaboration
Tue, 28 May 19
23/82
Comments: Early release. Preliminary fits tables can be found at this ftp URL