J/ApJS/232/8ivo://CDS.VizieR/J/ApJS/232/8doi:10.26093/cds/vizier.22320008CDSLiu T.Tozzi P.Wang J.-X.Brandt W.N.Vignali C.Xue Y.,Schneider D.P.Comastri A.Yang G.Bauer F.E.Paolillo M.Luo B.,Gilli R.Wang Q.D.Giavalisco M.Ji Z.Alexander D.M.Mainieri V.,Shemmer O.Koekemoer A.Risaliti G.2019-06-05T14:32:24Z2017-10-26T13:36:46ZCDS support team

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

cds-question@unistra.fractive-galactic-nucleix-ray-sourcesredshiftedWe present a detailed spectral analysis of the brightest active galactic nuclei (AGNs) identified in the 7Ms Chandra Deep Field-South (CDF-S) survey over a time span of 16 years. Using a model of an intrinsically absorbed power-law plus reflection, with possible soft excess and narrow Fe K{alpha} line, we perform a systematic X-ray spectral analysis, both on the total 7Ms exposure and in four different periods with lengths of 2-21 months. With this approach, we not only present the power-law slopes, column densities N_H_, observed fluxes, and absorption-corrected 2-10keV luminosities L_X_ for our sample of AGNs, but also identify significant spectral variabilities among them on timescales of years. We find that the N_H_ variabilities can be ascribed to two different types of mechanisms, either flux-driven or flux-independent. We also find that the correlation between the narrow Fe line EW and N_H_ can be well explained by the continuum suppression with increasing N_H_. Accounting for the sample incompleteness and bias, we measure the intrinsic distribution of N_H_ for the CDF-S AGN population and present reselected subsamples that are complete with respect to N_H_. The N_H_-complete subsamples enable us to decouple the dependences of N_H_ on L_X_ and on redshift. Combining our data with those from C-COSMOS, we confirm the anticorrelation between the average N_H_ and L_X_ of AGN, and find a significant increase of the AGN-obscured fraction with redshift at any luminosity. The obscured fraction can be described as f_obscured_~0.42(1+z)^0.60^.2017ApJS..232....8Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/232/8CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJS/121/473 : A diagnostic diagram for Seyfert 2 Galaxies (Bassani+, 1999)J/ApJS/139/369 : Chandra Deep Field South. 1 Ms catalog (Giacconi+, 2002)J/AJ/126/539 : The Chandra Deep Fields North and South (Alexander+, 2003)J/ApJS/161/21 : Extended Chandra Deep Field-South survey (Lehmer+, 2005)J/A+A/451/457 : X-ray properties of AGN in CDFS (Tozzi+, 2006)J/AJ/131/2373 : Extended Chandra Deep Field-South survey (Virani+, 2006)J/ApJ/681/1163 : Late-type galaxies in Chandra deep fields (Lehmer+, 2008)J/ApJS/179/19 : CDFS survey: 2 Ms source catalogs (Luo+, 2008)J/AJ/135/1505 : CDFs AGNs X-ray power-law photon index (Saez+, 2008)J/ApJS/184/158 : Chandra COSMOS survey I. (Elvis+, 2009)J/ApJS/180/102 : AEGIS-X: Chandra deep survey (Laird+, 2009)J/ApJ/728/58 : Swift-BAT survey of AGNs (Burlon+, 2011)J/A+A/533/A119 : GOODS-Herschel North and South catalogs (Elbaz+, 2011)J/ApJ/740/37 : Obscured AGN at z~0.5-1 in the CDFS (Luo+, 2011)J/ApJ/742/3 : Photometric catalogs for ECDF-S and CDF-N (Rafferty+, 2011)J/ApJS/195/10 : The CDF-S survey: 4Ms source catalogs (Xue+, 2011)J/ApJ/754/45 : IR properties of Swift/BAT X-ray AGNs (Ichikawa+, 2012)J/MNRAS/420/2190 : ECDFS sources with radio counterparts (Vattakunnel+, 2012)J/ApJ/748/124 : AGN X-ray variability in the 4Ms catalog (Young+, 2012)J/MNRAS/436/3759 : ECDFS sources optical/IR counterparts (Bonzini+, 2013)J/A+A/556/A114 : Obscured AGNs in CDF-S (Castello-Mor+, 2013)J/A+A/555/A42 : The XMM-CDFS catalogues (Ranalli+, 2013)J/MNRAS/443/1999 : X-ray spectral analysis of AGNs (Brightman+, 2014)J/A+A/564/A125 : AGN Torus model comparison of AGN in the CDFS (Buchner+, 2014)J/ApJ/802/89 : Luminosity function of X-ray-selected AGNs (Buchner+, 2015)J/A+A/576/A130 : Ultra-deep cat. of X-ray groups in ECDF-S (Finoguenov+, 2015)J/ApJ/807/129 : X-ray to MIR luminosities relation of AGNs (Stern, 2015)J/ApJ/819/62 : The COSMOS-Legacy Survey (CLS) catalog (Civano+, 2016)J/ApJ/825/7 : Evolution of ~6Ms CDF-S galaxies (Lehmer+, 2016)J/A+A/593/A55 : MEXSAS catalogue (Vagnetti+, 2016)J/ApJS/224/15 : Improved 2Ms and 250ks Chandra catalogs (Xue+, 2016)J/ApJ/831/145 : 6Ms Chandra long-term analyses of AGNs (Yang+, 2016)J/ApJ/835/74 : IR photom. of AGNs in Swift/BAT 70month cat. (Ichikawa+, 2017)J/ApJS/228/2 : Chandra Deep Field-South survey: 7Ms sources (Luo+, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/232/8https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/232/8http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/232/8https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/232/8https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/232/8http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/232/8GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/232/8/table3 (Spectral properties)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/232/8/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/232/8/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/232/8/table3?GETtext/xml+votable180.050000true52.9487561111-27.80814694440.0055555555555555566/35935 35957https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/232/8?format=asciiX-raydefaultJ/ApJS/232/8/table2Counts and fluxes of each source in each observation periodrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[20/988] Identifier from Luo+ 2017, J/ApJS/228/2meta.id;meta.mainintprimaryPerObservation period (see the "Description" section above)meta.id;obscharScts[0/13061] Soft band (0.5-2keV) countsctphot.count;em.X-rayinte_Scts[1/115] Uncertainty in Sctsctstat.errorintHcts[0/7706] Hard band (2-7keV) countsctphot.count;em.X-rayinte_Hcts[4/90] Uncertainty in Hctsctstat.errorintFS[0/680] Soft band (0.5-2keV) flux1e-16mW.m**-2phot.flux;em.X-rayfloate_FS[0/64] Lower uncertainty in FS1e-16mW.m**-2stat.errorfloatE_FS[0.02/39] Upper uncertainty in FS1e-16mW.m**-2stat.error;stat.maxfloatFH[0/816] Hard band (2-7keV) flux1e-16mW.m**-2phot.flux;em.X-rayfloate_FH[0/28] Lower uncertainty in FH1e-16mW.m**-2stat.errorfloatE_FH[0.2/37] Upper uncertainty in FH1e-16mW.m**-2stat.error;stat.maxfloatJ/ApJS/232/8/fekNarrow (table 4) and broad (table 5) Fe K{alpha} linesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLmeta.codecharID[26/988] Identifiermeta.id;meta.mainintEnergy[6/6.7] Rest-frame central energykeVem.energyfloate_EnergyNegative 1{sigma} error on EnergykeVstat.error;phys.energyfloatE_EnergyPositive 1{sigma} error on EnergykeVstat.error;stat.maxfloatEW[66/2569] Rest-frame equivalent-widtheVspect.line.eqWidthinte_EWNegative 1{sigma} error on EWeVstat.error;spect.line.eqWidthintE_EWPositive 1{sigma} error on EWeVstat.error;stat.maxintsigma[0.2/3]? Rest-frame width (only for table 5)keVspect.line.widthfloatnullablee_sigma? Negative 1{sigma} error on sigmakeVstat.errorfloatnullableE_sigma? Positive 1{sigma} error on sigmakeVstat.error;stat.maxfloatnullableJ/ApJS/232/8/table3Spectral propertiesNH[0.005/600] Hydrogen column density (3)1e+22cm**-2phys.columnDensityfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCptCompton ("thick": 22 occurrences or "thin")src.classcharID[20/988] Identifier in the 7Ms CDF-S catalog (Luo+ 2017, J/ApJS/228/2)meta.id;meta.mainintprimaryFeKDisplay the narrow or broad Fe K{alpha} lines data (tables 4 and 5)meta.ref.urlintnullablez[0.1/5.3] Redshift from Luo+, 2017, J/ApJS/228/2src.redshiftfloatf_zFlag on z (s=secure spectroscopic) (1)meta.codecharPerObservation period (see the "Description" section above) (2)meta.id;obscharl_NHLimit flag on NHmeta.code.errorchare_NH[0.005/514]? Lower 90% uncertainty in NH1e+22cm**-2stat.errorfloatnullableE_NH[0/554]? Upper 90% uncertainty in NH1e+22cm**-2stat.error;stat.maxfloatnullableGamma[1.4/2.4]? Power-law slopespect.indexfloatnullablef_Gamma[f] f=fixedmeta.codechare_Gamma[0.02/0.4]? Lower 90% uncertainty in Gammastat.errorfloatnullableE_Gamma[0.02/0.4]? Upper 90% uncertainty in Gammastat.error;stat.maxfloatnullableSRate? Soft band (0.5-2keV) net count rate; in photon/cm^2^/s units (4)ph.cm**-2.s**-1phot.count;em.X-rayfloatnullableHRate? Hard band (2-7keV) net count rate in photon/cm^2^/s units (4)ph.cm**-2.s**-1phot.count;em.X-rayfloatnullablelogL[39.5/48]? log 2-10keV unabsorbed luminosity; in erg/s (5)log(1e-07W)phys.luminosity;em.X-rayfloatnullablee_logL[0/3]? Lower 90% uncertainty in logLlog(1e-07W)stat.errorfloatnullableE_logL[0/5]? Upper 90% uncertainty in logLlog(1e-07W)stat.error;stat.maxfloatnullableC-NH[-1/24] Completeness flag (6)meta.codefloatModelPeriod number in which soft excess component added (see the "Description" section above) (7)meta.id;obscharL17Display data from Luo+, 2017, J/ApJS/228/2, main sources (table 4)meta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlchar_RAPositions from Luo+, 2017, J/ApJS/228/2, main source catalog (table 4) (right ascension part)degpos.eq.ra;meta.main_DEPositions from Luo+, 2017, J/ApJS/228/2, main source catalog (table 4) (declination part)degpos.eq.dec;meta.main