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Fermi/LAT Observations of Swift/BAT Seyfert Galaxies: On the Contribution of Radio-Quiet Active Galactic Nuclei to the Extragalactic gamma-Ray BackgroundWe present the analysis of 2.1 years of Fermi Large Area Telescope (LAT) data on 491 Seyfert galaxies detected by the Swift Burst Alert Telescope (BAT) survey. Only the two nearest objects, NGC 1068 and NGC 4945, which were identified in the Fermi first year catalog, are detected. Using Swift/BAT and radio 20 cm fluxes, we define a new radio-loudness parameter R(sub X,BAT) where radio-loud objects have logR(sub X,BAT) > -4.7. Based on this parameter, only radio-loud sources are detected by Fermi/LAT. An upper limit to the flux of the undetected sources is derived to be approx.2x10(exp -11) photons/sq cm/s, approximately seven times lower than the observed flux of NGC 1068. Assuming a median redshift of 0.031, this implies an upper limit to the gamma-ray (1-100 GeV) luminosity of < approx.3x10(exp 41) erg/s. In addition, we identified 120 new Fermi/LAT sources near the Swift/BAT Seyfert galaxies with significant Fermi/LAT detections. A majority of these objects do not have Swift/BAT counterparts, but their possible optical counterparts include blazars, flat-spectrum radio quasars, and quasars.
Document ID
20120001991
Acquisition Source
Goddard Space Flight Center
Document Type
Reprint (Version printed in journal)
Authors
Teng, Stacy H.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Mushotzky, Richard F.
(Maryland Univ. College Park, MD, United States)
Sambruna, Rita M.
(George Mason Univ. Fairfax, VA, United States)
Davis, David S.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Reynolds, Christopher S.
(Maryland Univ. College Park, MD, United States)
Date Acquired
August 25, 2013
Publication Date
December 1, 2011
Publication Information
Publication: The Astrophysical Journal
Publisher: American Astronomical Society
Volume: 742
Issue: 2
Subject Category
Astrophysics
Report/Patent Number
GSFC.JA.5671.2011
GSFC.JA.6622.2012
Funding Number(s)
CONTRACT_GRANT: NNG06EO90A
Distribution Limits
Public
Copyright
Other

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