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The Radio/Gamma-Ray Connection in Active Galactic Nuclei in the Era of the Fermi Large Area TelescopeWe present a detailed statistical analysis of the correlation between radio and gamma-ray emission of the active galactic nuclei (AGNs) detected by Fermi during its first year of operation, with the largest data sets ever used for this purpose.We use both archival interferometric 8.4 GHz data (from the Very Large Array and ATCA, for the full sample of 599 sources) and concurrent single-dish 15 GHz measurements from the OwensValley RadioObservatory (OVRO, for a sub sample of 199 objects). Our unprecedentedly large sample permits us to assess with high accuracy the statistical significance of the correlation, using a surrogate data method designed to simultaneously account for common-distance bias and the effect of a limited dynamical range in the observed quantities. We find that the statistical significance of a positive correlation between the centimeter radio and the broadband (E > 100 MeV) gamma-ray energy flux is very high for the whole AGN sample, with a probability of <10(exp -7) for the correlation appearing by chance. Using the OVRO data, we find that concurrent data improve the significance of the correlation from 1.6 10(exp -6) to 9.0 10(exp -8). Our large sample size allows us to study the dependence of correlation strength and significance on specific source types and gamma-ray energy band. We find that the correlation is very significant (chance probability < 10(exp -7)) for both flat spectrum radio quasars and BL Lac objects separately; a dependence of the correlation strength on the considered gamma-ray energy band is also present, but additional data will be necessary to constrain its significance.
Document ID
20120002553
Acquisition Source
Goddard Space Flight Center
Document Type
Reprint (Version printed in journal)
Authors
Ackermann, M.
(Stanford Univ. Stanford, CA, United States)
Ajello, M.
(Stanford Univ. Stanford, CA, United States)
Allafort, A.
(Stanford Univ. Stanford, CA, United States)
Angelakis, E.
(Max-Planck-Inst. fuer Radioastronomie Bonn, Germany)
Axelsson, M.
(Stockholm Univ. Sweden)
Baldini, L.
(Istituto Nazionale di Fisica Nucleare Trieste, Italy)
Ballet, J.
(Paris VII Univ. France)
Barbiellini, G.
(Istituto Nazionale di Fisica Nucleare Padova, Italy)
Bastieri, D.
(Istituto Nazionale di Fisica Nucleare Padova, Italy)
Bellazzini, R.
(Istituto Nazionale di Fisica Nucleare Trieste, Italy)
Berenji, B.
(Stanford Univ. Stanford, CA, United States)
Blandford, R. D.
(Stanford Univ. Stanford, CA, United States)
Bloom, E. D.
(Stanford Univ. Stanford, CA, United States)
Bonamente, E.
(Istituto Nazionale di Fisica Nucleare Perugia, Italy)
Borgland, A. W.
(Stanford Univ. Stanford, CA, United States)
Bouvier, A.
(California Univ. Santa Cruz, CA, United States)
Bregeon, J.
(Istituto Nazionale di Fisica Nucleare Trieste, Italy)
Brez, A.
(Istituto Nazionale di Fisica Nucleare Trieste, Italy)
Brigida, M.
(Istituto Nazionale di Fisica Nucleare Bari, Italy)
Bruel, P.
(Ecole Polytechnique Palaiseau, France)
Gehrels, N.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Hays, E.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
MeEnery, J. E.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Scargle, J. D.
(NASA Ames Research Center Moffett Field, CA, United States)
Thompson, D. J.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
August 25, 2013
Publication Date
November 1, 2011
Publication Information
Publication: The Astrophysical Journal
Volume: 741
Issue: 30
Subject Category
Astronomy
Report/Patent Number
GSFC.JA.5653.2011
Distribution Limits
Public
Copyright
Other

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