Reference : Spectral Energy Distributions of Hard X-Ray Selected Active Galactic Nuclei in the XM...
Scientific journals : Article
Physical, chemical, mathematical & earth Sciences : Space science, astronomy & astrophysics
http://hdl.handle.net/2268/24953
Spectral Energy Distributions of Hard X-Ray Selected Active Galactic Nuclei in the XMM-Newton Medium Deep Survey
English
Polletta, M. [Center for Astrophysics and Space Sciences, University of California, San Diego, La Jolla, CA 92093-0424.]
Tajer, M. [INAF-Osservatorio di Brera, via Brera 28, 20121 Milano, Italy.; Università degli studi di Milano-Bicocca, Dipartimento di fisica, Piazza della Scienza 3, 20126 Milano, Italy.]
Maraschi, L. [INAF-Osservatorio di Brera, via Brera 28, 20121 Milano, Italy.]
Trinchieri, G. [INAF-Osservatorio di Brera, via Brera 28, 20121 Milano, Italy.]
Lonsdale, C. J. [Center for Astrophysics and Space Sciences, University of California, San Diego, La Jolla, CA 92093-0424.]
Chiappetti, L. [INAF-IASF Milano, via Bassini 15, I-20133 Milano, Italy.]
Andreon, S. [INAF-Osservatorio di Brera, via Brera 28, 20121 Milano, Italy.]
Pierre, M. [CEA Saclay, DSM/DAPNIA, Service d'Astrophysique, 91191 Gif-sur-Yvette, France.]
Le Fèvre, O. [Laboratoire d'Astrophysique de Marseille, UMR 6110 CNRS-Université de Provence, Traverse du Siphon, BP 8, 13012 Marseille, France.]
Zamorani, G. [INAF-Osservatorio di Bologna, via Ranzani 1, 40127 Bologna, Italy.]
Maccagni, D. [INAF-IASF Milano, via Bassini 15, I-20133 Milano, Italy.]
Garcet, Olivier [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Astroph. extragalactique et observations spatiales (AEOS) >]
Surdej, Jean mailto [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Astroph. extragalactique et observations spatiales (AEOS) >]
Franceschini, A. [Dipartimento di Astronomia, Università di Padova, Vicolo dell'Osservatorio 2, I-35122, Padova, Italy.]
Alloin, D. [CEA Saclay, DSM/DAPNIA, Service d'Astrophysique, 91191 Gif-sur-Yvette, France.]
Shupe, D. L. [Spitzer Science Center, California Institute of Technology, 100-22, Pasadena, CA 91125.]
Surace, J. A. [Spitzer Science Center, California Institute of Technology, 100-22, Pasadena, CA 91125.]
Fang, F. [Spitzer Science Center, California Institute of Technology, 100-22, Pasadena, CA 91125.]
Rowan-Robinson, M. [Astrophysics Group, Blackett Laboratory, Imperial College, Prince Consort Road, London, SW7 2BW, UK.]
Smith, H. E. [Center for Astrophysics and Space Sciences, University of California, San Diego, La Jolla, CA 92093-0424.]
Tresse, L. [Laboratoire d'Astrophysique de Marseille, UMR 6110 CNRS-Université de Provence, Traverse du Siphon, BP 8, 13012 Marseille, France.]
2007
Astrophysical Journal
University of Chicago Press
663
81-102
Yes (verified by ORBi)
International
0004-637X
Chicago
IL
[en] Infrared: Galaxies ; Galaxies: Quasars: General ; X-Rays: Galaxies ; Galaxies: Active
[en] We present the SEDs of a hard X-ray selected sample containing 136 sources with F[SUB]2-10keV[/SUB]>10[SUP]-14[/SUP] erg cm[SUP]-2[/SUP] s[SUP]-1[/SUP] 132 are AGNs. The sources are detected in a 1 deg[SUP]2[/SUP] area of the XMM-Newton Medium Deep Survey where optical data from the VVDS and CFHTLS and infrared data from the SWIRE survey are available. Based on a SED fitting technique we derive photometric redshifts with sigma(1+z)=0.11 and 6% of outliers and identify AGN signatures in 83% of the objects. This fraction is higher than derived when a spectroscopic classification is available. The remaining 17[SUP]+9[/SUP][SUB]-6[/SUB]% of AGNs show star-forming galaxy SEDs (SF class). The sources with AGN signatures are divided in two classes, AGN1 (33[SUP]+6[/SUP][SUB]-1[/SUB]%) and AGN2 (50[SUP]+6[/SUP][SUB]-11[/SUB]%). The AGN1 and AGN2 classes include sources whose SEDs are fitted by type 1 and type 2 AGN templates, respectively. On average, AGN1s show soft X-ray spectra, consistent with being unabsorbed, while AGN2s and SFs show hard X-ray spectra, consistent with being absorbed. The analysis of the average SEDs as a function of X-ray luminosity shows a reddening of the infrared SEDs, consistent with a decreasing contribution from the host galaxy at higher luminosities. The AGNs in the SF classes are likely obscured in the mid-infrared, as suggested by their low L[SUB]3-20mum[/SUB]/L[SUP]corr[/SUP][SUB]0.5-10keV[/SUB] ratios. We confirm the previously found correlation for AGNs between the radio luminosity and the X-ray and the mid-infrared luminosities. The X-ray-radio correlation can be used to identify heavily absorbed AGNs. However, the estimated radio fluxes for the missing AGN population responsible for the bulk of the background at E>10 keV are too faint to be detected even in the deepest current radio surveys.
Researchers ; Professionals
http://hdl.handle.net/2268/24953
10.1086/518113
http://esoads.eso.org/abs/2007ApJ...663...81P
The authors thank http://arxiv.org/abs/astro-ph/0703255 for their preprint deposit authorization. The original publication can be found in the Astrophysical Journal.
http://arxiv.org/abs/astro-ph/0703255

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