J/ApJ/802/89ivo://CDS.VizieR/J/ApJ/802/89doi:10.26093/cds/vizier.18020089CDSBuchner J.Georgakakis A.Nandra K.Brightman M.Menzel M.-L.Liu Z.,Hsu L.-T.Salvato M.Rangel C.Aird J.Merloni A.Ross N.2017-10-18T13:46:43Z2015-08-27T13:31:29ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frredshiftedactive-galactic-nucleisurveysx-ray-sourcesWe aim to constrain the evolution of active galactic nuclei (AGNs) as a function of obscuration using an X-ray-selected sample of ~2000 AGNs from a multi-tiered survey including the CDFS, AEGIS-XD, COSMOS, and XMM-XXL fields. The spectra of individual X-ray sources are analyzed using a Bayesian methodology with a physically realistic model to infer the posterior distribution of the hydrogen column density and intrinsic X-ray luminosity. We develop a novel non-parametric method that allows us to robustly infer the distribution of the AGN population in X-ray luminosity, redshift, and obscuring column density, relying only on minimal smoothness assumptions. Our analysis properly incorporates uncertainties from low count spectra, photometric redshift measurements, association incompleteness, and the limited sample size. We find that obscured AGNs with N_H_>10^22^/cm2 account for 77_-5_^+4^% of the number density and luminosity density of the accretion supermassive black hole population with L_X_>10^43^erg/s, averaged over cosmic time. Compton-thick AGNs account for approximately half the number and luminosity density of the obscured population, and 38_-7_^+8^% of the total. We also find evidence that the evolution is obscuration dependent, with the strongest evolution around N_H_{approx}10^23^/cm2. We highlight this by measuring the obscured fraction in Compton-thin AGNs, which increases toward z~3, where it is 25% higher than the local value. In contrast, the fraction of Compton-thick AGNs is consistent with being constant at {approx}35%, independent of redshift and accretion luminosity. We discuss our findings in the context of existing models and conclude that the observed evolution is, to first order, a side effect of anti-hierarchical growth.2015ApJ...802...89Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/802/89CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/802/89https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/802/89http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/802/89https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/802/89https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/802/89http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/802/89GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalX-raydefaultJ/ApJ/802/89/table5Space density estimates as a function of luminosity, redshift and obscurationrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlogL0[42/46] Lower edge of model luminosity bin (G1)log(1e+07W)phys.luminosityfloatlogL1[42/46] Upper edge of model luminosity bin (G1)log(1e+07W)phys.luminosityfloatz0[0/4] Lower edge of model redshift binsrc.redshiftfloatz1[0.1/7] Upper edge of model redshift binsrc.redshiftfloatlogNH0[20/24] Lower edge of model neutral hydrogen equivalent column density bin (G1)log(cm**-2)phys.columnDensity;meta.modelled;stat.minfloatlogNH1[21/26] Upper edge of model neutral hydrogen equivalent column density bin (G1)log(cm**-2)phys.columnDensity;meta.modelled;stat.maxfloatlogphi0[-9.2/-4.1] The 10% quantile of space density posterior (2)log(Mpc**-3)phys.luminosity.funfloatlogphi1[-7.1/-3.3] The 90% quantile of space density posterior (2)log(Mpc**-3)phys.luminosity.funfloatJ/ApJ/802/89/figure4Total AGN Intrinsic 2-10keV Luminosity function, including Compton-thickrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintz0[0/4] Lower edge of redshift binsrc.redshiftfloatz1[0.1/7] Upper edge of redshift binsrc.redshiftfloatlogL0[42/46] Lower edge of luminosity bin (G1)log(1e+07W)phys.luminosityfloatlogL1[42/46] Upper edge of luminosity bin (G1)log(1e+07W)phys.luminosityfloatlogphilo10% quantile of the posterior of the space density (G1)log(Mpc**-3)phys.luminosity.funfloatlogphihi90% quantile of the posterior of the space density (G1)log(Mpc**-3)phys.luminosity.funfloatJ/ApJ/802/89/figure7Obscured and Compton-thick fractions as a function of luminosity and redshiftrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlogL0[42/46] Lower edge of luminosity bin (G1)log(1e+07W)phys.luminosityfloatlogL1[42/46] Upper edge of luminosity bin (G1)log(1e+07W)phys.luminosityfloatz0[0/4] Lower edge of redshift binsrc.redshiftfloatz1[0.1/7] Upper edge of redshift binsrc.redshiftfloatobscflo[0/1] Compton-thin obscured fraction 10% quantilephot.flux;arith.ratiofloatobscfhi[0/1] Compton-thin obscured fraction 90% quantilephot.flux;arith.ratiofloatobscfpch[0/1] Compton-thin constant-value estimatephot.flux;arith.ratiofloatobscfpcs[0/1] Compton-thin obscured fraction constant-slope estimatephot.flux;arith.ratiofloatCTKflo[0/1] Compton-thick fraction 10% quantilephot.flux;arith.ratiofloatCTKfhi[0/1] Compton-thick fraction 90% quantilephot.flux;arith.ratiofloatCTKfpch[0/1] Compton-thick fraction constant-value estimatephot.flux;arith.ratiofloatCTKfpcs[0/1] Compton-thick fraction constant-slope estimatephot.flux;arith.ratiofloat