Astronomy and Astrophysics – Astrophysics – High Energy Astrophysical Phenomena
Scientific paper
2011-08-05
Astronomy and Astrophysics
Astrophysics
High Energy Astrophysical Phenomena
Accepted for publication in The Astrophysical Journal. 103 pages, 45 figures, 9 tables. Full tables are available at http://
Scientific paper
The second catalog of active galactic nuclei (AGNs) detected by the Fermi Large Area Telescope (LAT) in two years of scientific operation is presented. The Second LAT AGN Catalog (2LAC) includes 1017 gamma-ray sources located at high Galactic latitudes (|b|>10{\deg}) that are detected with a test statistic greater than 25 and associated statistically with AGNs. However some of these are affected by analysis issues and some are associated with multiple AGNs. Consequently we define a clean sample which includes 886 AGNs, comprising 395 BL Lacertae objects (BL Lacs), 310 flat-spectrum radio quasars (FSRQs), 157 candidate blazars of unknown type (i.e., with broad-band blazar characteristics but with no optical spectral measurement yet), eight misaligned AGNs, four narrow-line Seyfert 1 (NLS1s), 10 AGNs of other types and two starburst galaxies. Where possible, the blazars have been further classified based on their spectral energy distributions (SEDs) as archival radio, optical, and X-ray data permit. While almost all FSRQs have a synchrotron-peak frequency 10^14 Hz, about half of the BL Lacs have a synchrotron-peak frequency >10^15 Hz. The 2LAC represents a significant improvement relative to the First LAT AGN Catalog (1LAC), with 52% more associated sources. The full characterization of the newly detected sources will require more broad-band data. Various properties, such as gamma-ray fluxes and photon power law spectral indices, redshifts, gamma-ray luminosities, variability, and archival radio luminosities---and their correlations are presented and discussed for the different blazar classes. The general trends observed in 1LAC are confirmed.
No associations
LandOfFree
The Second Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Second Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Second Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-962