J/ApJS/236/48ivo://CDS.VizieR/J/ApJS/236/48doi:10.26093/cds/vizier.22360048CDSKocevski D.D.Hasinger G.Brightman M.Nandra K.Georgakakis A.,Cappelluti N.Civano F.Li Y.Li Y.Aird J.Alexander D.M.,Almaini O.Brusa M.Buchner J.Comastri A.Conselice C.J.,Dickinson M.A.Finoguenov A.Gilli R.Koekemoer A.M.Miyaji T.,Mullaney J.R.Papovich C.Rosario D.Salvato M.Silverman J.D.,Somerville R.S.Ueda Y.2019-01-07T08:44:53Z2018-10-17T13:51:36ZCDS support team

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

cds-question@unistra.frx-ray-sourcessurveysredshiftedWe present the X-UDS survey, a set of wide and deep Chandra observations of the Subaru-XMM Deep/UKIDSS Ultra Deep Survey (SXDS/UDS) field. The survey consists of 25 observations that cover a total area of 0.33deg^2^. The observations are combined to provide a nominal depth of ~600ks in the central 100arcmin^2^ region of the field that has been imaged with Hubble/WFC3 by the CANDELS survey and ~200ks in the remainder of the field. In this paper, we outline the survey's scientific goals, describe our observing strategy, and detail our data reduction and point source detection algorithms. Our analysis has resulted in a total of 868 band-merged point sources detected with a false-positive Poisson probability of <1x10^-4^. In addition, we present the results of an X-ray spectral analysis and provide best-fitting neutral hydrogen column densities, N_H_, as well as a sample of 51 Compton-thick active galactic nucleus candidates. Using this sample, we find the intrinsic Compton-thick fraction to be 30%-35% over a wide range in redshift (z=0.1-3), suggesting the obscured fraction does not evolve very strongly with epoch. However, if we assume that the Compton-thick fraction is dependent on luminosity, as is seen for Compton-thin sources, then our results are consistent with a rise in the obscured fraction out to z~3. Finally, an examination of the host morphologies of our Compton-thick candidates shows a high fraction of morphological disturbances, in agreement with our previous results.2018ApJS..236...48Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/236/48CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/chandra : The Chandra Archive Log (CXC, 1999-2014)II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)J/AJ/126/539 : The Chandra Deep Fields North and South (Alexander+, 2003)J/MNRAS/356/568 : Deep Chandra survey of the Groth Strip (Nandra+, 2005)J/ApJS/179/124 : Subaru/XMM-Newton deep survey (SXDS) III. (Ueda+, 2008)J/ApJS/184/158 : Chandra COSMOS survey I. (Elvis+, 2009)J/ApJS/180/102 : AEGIS-X: Chandra deep survey (Laird+, 2009)J/MNRAS/414/3084 : Multi-waveband analysis of 12um galaxies (Brightman+, 2011)J/A+A/533/A119 : GOODS-Herschel North and South catalogs (Elbaz+, 2011)J/ApJ/739/57 : Ultra hard X-ray AGNs in the Swift/BAT survey (Koss+, 2011)J/ApJS/195/10 : The CDF-S survey: 4Ms source catalogs (Xue+, 2011)J/ApJS/201/30 : The Chandra COSMOS survey. III. (Civano+, 2012)J/ApJ/769/80 : Spitzer/IRAC observations of five deep fields (Ashby+, 2013)J/ApJS/206/10 : CANDELS multiwavelength catalog (Galametz+, 2013)J/MNRAS/443/1999 : X-ray spectral analysis of AGNs (Brightman+, 2014)J/ApJ/802/89 : Luminosity function of X-ray-selected AGNs (Buchner+, 2015)J/ApJS/220/10 : AEGIS-X Deep survey of EGS (AEGIS-XD) (Nandra+, 2015)J/ApJ/815/L13 : Compton-thick AGNs from 70-month Swift/BAT (Ricci+, 2015)J/ApJS/224/15 : Improved 2Ms and 250ks Chandra catalogs (Xue+, 2016)J/ApJS/235/17 : NuSTAR Extragalactic Surveys: UDS field (Masini+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/236/48https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/236/48http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/236/48https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/236/48https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/236/48http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/236/48GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/236/48/table1 (Observation log)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/236/48/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/236/48/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/236/48/table1?GETtext/xml+votable180.050000true34.2082083-5.26649440.005555555555555556Cone search capability for table J/ApJS/236/48/xuds (Chandra X-UDS source catalog: basic source properties, fluxes and HRs and best-fit spectral parameters (tables 4-6))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/236/48/xuds?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/236/48/xuds?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/236/48/xuds?GETtext/xml+votable180.050000true34.45419-5.385106110.0055555555555555566/17677 17679 17688 17690https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/236/48?format=asciiX-raydefaultJ/ApJS/236/48/table1Observation logrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFieldField nameobs.fieldcharObsID[17287/17311] Chandra ObsIDmeta.noteintRAJ2000[2] Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000[5] Degree of declination (J2000)pos.eq.dec;meta.mainStartStart time (UT)time.epochnullableExp[44.6/51.2] Exposure timekstime.duration;obs.exposurefloatRoll[70.2/106.2] Roll angledeginstr.offsetfloatJ/ApJS/236/48/xudsChandra X-UDS source catalog: basic source properties, fluxes and HRs and best-fit spectral parameters (tables 4-6)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintXUDS[1/868] Internal identifier (<[KHB2018] xuds NNN> in Simbad)meta.id;meta.mainintCXOUDSChandra X-UDS catalog identifier (JHHMMSS.s+DDMMSS)meta.idcharRAJ2000[34/34.8] Right Ascension (J2000)degpos.eq.ra;meta.mainDEJ2000[-5.5/-4.9] Declination (J2000)degpos.eq.dec;meta.mainePos[0.1/1.4] Positional uncertaintyarcsecstat.error;posfloatOAA[3.4/12.1] Off axis anglearcmininstr.offsetfloatFBcts[6/5859] Full 0.5-10keV band countsctphot.count;em.X-rayintFBbck[1.9/65] Background counts in 0.5-10keV bandctinstr.background;em.X-ray.mediumfloatSBcts[0/3720] Soft 0.5-2keV band countsctphot.count;em.X-ray.softintSBbck[0.5/16] Background counts in 0.5-2keV bandctinstr.background;em.X-ray.softfloatHBcts[2/2069] Hard 2-10keV band countsctphot.count;em.X-ray.hardintHBbck[1.5/56] Background counts in 2-10keV bandctinstr.background;em.X-ray.mediumfloatUBcts[1/675] Ultra hard 5-10keV band countsctphot.count;em.X-ray.hardintUBbck[0.9/38.5] Background counts in 5-10keV bandctinstr.background;em.X-ray.mediumfloatDetDetection code (1)meta.code;instr.saturationcharlogP[-8/-4] log minimum Poisson false detection probability (2)stat.fit.goodnessfloatl_FbF68% upper limit flag on FbFmeta.code.errorcharFbF[0.1/497] Full 0.5-10keV Bayesian flux (3)1e-18W.m**-2phot.flux;em.X-rayfloatE_FbF[0/10]? Upper uncertainty in FbF1e-18W.m**-2stat.error;stat.maxfloatnullablee_FbF[0/9]? Lower uncertainty in FbF1e-18W.m**-2stat.errorfloatnullablel_FbS68% upper limit flag on FbSmeta.code.errorcharFbS[0.03/152] Soft 0.5-2keV Bayesian flux (3)1e-18W.m**-2phot.flux;em.X-ray.softfloatE_FbS[0/5]? Upper uncertainty in FbS1e-18W.m**-2stat.error;stat.maxfloatnullablee_FbS[0/5]? Lower uncertainty in FbS1e-18W.m**-2stat.errorfloatnullablel_FbH68% upper limit flag on FbSmeta.code.errorcharFbH[0.1/281] Hard 2-10keV Bayesian flux (3)1e-18W.m**-2phot.flux;em.X-ray.hardfloatE_FbH[0/11]? Upper uncertainty in FbH1e-18W.m**-2stat.error;stat.maxfloatnullablee_FbH[0/10]? Lower uncertainty in FbH1e-18W.m**-2stat.errorfloatnullablel_FbU68% upper limit flag on FbUmeta.code.errorcharFbU[0.2/141] Ultra hard 5-10keV Bayesian flux (3)1e-18W.m**-2phot.flux;em.X-ray.hardfloatE_FbU[0.3/12]? Upper uncertainty in FbU1e-18W.m**-2stat.error;stat.maxfloatnullablee_FbU[0.4/11]? Lower uncertainty in FbU1e-18W.m**-2stat.errorfloatnullablel_FcF68% upper limit flag on FcFmeta.code.errorcharFcF[0.05/497] Full 0.5-10keV classical flux (4)1e-18W.m**-2phot.flux;em.X-rayfloatE_FcF[0.2/10]? Upper uncertainty in FcF1e-18W.m**-2stat.error;stat.maxfloatnullablee_FcF[0.2/9]? Lower uncertainty in FcF1e-18W.m**-2stat.errorfloatnullablel_FcS68% upper limit flag on FcSmeta.code.errorcharFcS[0.04/152] Soft 0.5-2keV classical flux (4)1e-18W.m**-2phot.flux;em.X-ray.softfloatE_FcS[0.08/5]? Upper uncertainty in FcS1e-18W.m**-2stat.error;stat.maxfloatnullablee_FcS[0.06/5]? Lower uncertainty in FcS1e-18W.m**-2stat.errorfloatnullablel_FcH68% upper limit flag on FcHmeta.code.errorcharFcH[0.1/281] Hard 2-10keV classical flux (4)1e-18W.m**-2phot.flux;em.X-ray.hardfloatE_FcH[0.3/14]? Upper uncertainty in FcH1e-18W.m**-2stat.error;stat.maxfloatnullablee_FcH[0.3/10]? Lower uncertainty in FcH1e-18W.m**-2stat.errorfloatnullablel_FcU68% upper limit flag on FcHmeta.code.errorcharFcU[0.2/142] Ultra hard 5-10keV classical flux (4)1e-18W.m**-2phot.flux;em.X-ray.hardfloatE_FcU[0.5/20]? Upper uncertainty in FcU1e-18W.m**-2stat.error;stat.maxfloatnullablee_FcU[0.4/12]? Lower uncertainty in FcU1e-18W.m**-2stat.errorfloatnullableHRb[-1/1] Bayesian hardness ratio (5)phot.flux;arith.ratiofloatE_HRb[0.01/0.9] Upper 1{sigma} uncertainty in HRbstat.error;stat.maxfloate_HRb[0.01/0.8] Lower 1{sigma} uncertainty in HRbstat.errorfloatHRc[-99/1] Classical hardness ratio (5)phot.flux;arith.ratiofloatPhot[0/2]? Photometric quality flag (6)meta.code.qual;photintnullableCts[2/5824] Full 0.5-10keV band counts from best fitctphot.count;em.X-rayintzsp[0.01/5.8]? Optical counterpart spectroscopic redshift (7)src.redshiftfloatnullablelogNH[20/26] log HI column densitylog(cm**-2)phys.columnDensityfloate_logNH[0.06/2]? Lower 90% uncertainty in logNH (8)log(cm**-2)stat.errorfloatnullableE_logNH[0.09/3]? Upper 90% uncertainty in logNH (8)log(cm**-2)stat.error;stat.maxfloatnullablegamma[1.2/10] Best-fit power law indexspect.indexfloate_gamma[0.05/5]? Lower 90% uncertainty in gamma (8)stat.errorfloatnullableE_gamma[0.05/8]? Upper 90% uncertainty in gamma (8)stat.error;stat.maxfloatnullablelogF[-25.2/-12.4] log observed 0.5-8keV band flux; in units of erg/s/cm^-2^.log(mW.m**-2)phot.flux;em.X-rayfloatlogL[32.7/53.6]? log 2-10keV rest-frame luminosity absorption-corrected; in units of erg/slog(1e-07W)phys.luminosity;em.X-rayfloatnullableCANDELSDisplay data from CANDELS (Galametz+, 2013, J/ApJS/206/10) within 0.5"meta.ref.urlintnullable