J/ApJS/245/3ivo://CDS.VizieR/J/ApJS/245/3doi:10.26093/cds/vizier.22450003CDSGrasha K.Darling J.Bolatto A.Leroy A.K.Stocke J.T.2020-09-08T08:14:27Z2020-04-29T08:44:17ZCDS support team

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

cds-question@unistra.fractive-galactic-nucleiredshiftedh-i-line-emissionradio-astronomyWe present the results of a large search for intrinsic HI 21cm and OH 18cm absorption in 145 compact radio sources in the redshift range 0.02<z<3.8 with the Green Bank Telescope. We redetect HI 21cm absorption toward six known absorption systems, but detect no new HI or OH absorption in 102 interference-free sources. Seventy-nine sources have not previously been observed for HI 21cm absorption. We recover a mean optical depth limit of {tau}_3{sigma}_<0.023 for all the nondetections in the survey. Our results do not support the high intrinsic absorption rates found by previous studies in compact radio sources at low redshift. Our results do, however, support the hypothesis proposed by Curran+ (2019MNRAS.484.1182C) that high ultraviolet (UV) luminosity active galactic nuclei do not show intrinsic HI 21cm absorption, confirming a threshold of L_UV_=10^23^W/Hz, above which our intrinsic absorption fraction is zero (54 sources). The exact nature of the UV luminosity effect on HI absorption systems remains ambiguous. We additionally find no statistical correlation between the 1.4GHz radio luminosity or the source size and the 21cm absorption detection rate. We attribute the lack of intrinsic absorption in our survey to the UV luminosity effect caused by an optical selection bias and a decreased column density sensitivity with increasing redshift due to lower radio continuum flux densities, high radio frequency interference, and higher telescope system temperatures at low frequencies.2019ApJS..245....3Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/245/3CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/2 : Molonglo Reference Catalog of Radio Sources (Large+ 1981)VIII/37 : The Third Bologna Survey (B3) (Ficarra+ 1985)VIII/17 : The North 20cm Survey (White+ 1992)VIII/42 : Texas Survey of radio sources at 365MHz (Douglas+ 1996)VIII/34 : Parkes Half-Jansky Flat-Spectrum Sample (Drinkwater+ 1997)VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)II/282 : The SDSS Photometric Catalog, Release 6 (Adelman-McCarthy+, 2007)J/ApJS/95/1 : Atlas of Quasar Energy Distributions (Elvis+ 1994)J/A+AS/115/11 : Optical identifications of radio sources (Stickel+, 1996)J/A+AS/124/259 : Westerbork Northern Sky Survey I. (Rengelink+ 1997)J/A+AS/131/303 : GHz-Peaked-Spectrum radio sources (Stanghellini+ 1998)J/A+A/342/378 : 6 and 20cm flux densities of radio galaxies (Gurvits+ 1999)J/ApJS/128/17 : VLBA obs. of radio reference frame sources III. (Fey+, 2000)J/ApJS/131/95 : VSOP 5 GHz continuum survey (Fomalont+, 2000)J/A+A/369/380 : CSS/GPS radio sources VLA observations (Fanti+, 2001)J/A+A/386/97 : Parkes quarter-Jansky flat-spectrum sample (Jackson+, 2002)J/other/NewA/11.27 : 2MASS observation of BL Lac objects (Chen+, 2005)J/AJ/130/1345 : Optical-infrared colors of CORALS QSOs (Ellison+, 2005)J/AJ/130/1389 : Linear polarization of AGN jets at 15GHz (Lister+, 2005)J/MNRAS/368/1411 : Flat-spectrum symmetric radio sources (Augusto+, 2006)J/ApJ/636/610 : Damped Ly{alpha} systems at z<1.65 (Rao+, 2006)J/ApJ/664/53 : UV photometry of GALEX QSO candidates (Atlee+, 2007)J/ApJS/171/61 : All-Sky Survey of Flat-Spectrum Rad. Sources (Healey+, 2007)J/A+A/463/97 : Optical observations of GPS radio sources (Labiano+, 2007)J/ApJS/175/97 : CGRaBS: survey of {gamma}-ray blazar cand. (Healey+, 2008)J/AJ/136/580 : Sixth VLBA calibrator survey: VCS6 (Petrov+, 2008)J/AJ/138/845 : BVRI observations of 235 bright quasars (Ojha+, 2009)J/MNRAS/440/696 : HI absorption in nearby radio galaxies (Allison+, 2014)J/A+A/575/A44 : HI absorption in flux-selected radio AGNs (Gereb+, 2015)J/MNRAS/462/4197 : HI 21-cm absorption in redshifted galaxies (Curran+, 2016)J/AJ/151/74 : VLA/VLBA obscured radio-loud AGN (Yan+, 2016)J/A+A/604/A43 : HI in nearby radio sources (Maccagni+, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/245/3https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/245/3http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/245/3https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/245/3https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/245/3http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/245/3GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/245/3/table1 (Observations of intrinsic HI and OH lines toward compact radio sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/245/3/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/245/3/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/245/3/table1?GETtext/xml+votable180.050000true5.36416773.2116390.0055555555555555566/110 124 180 579 1450 1521 1701 2063 2245 2323 2331 2397 2414 2631 2836 3820 3886 3918 4649 4695 4770 5458 5767 5806 5817 6164 6252 6377 6536 6576 6641 7195 7296 7426 7570 7857 7969 8626 8858 9403 10163 10288 10422 10432 10654 10795 10815 11024 11430 11551 11639 11715 12047 12094 12301 13410 13496 15023 15067 15147 15286 15341 15823 15936 16027 16253 16281 16298 17516 17909 18005 18035 18271 18387 18669 18895 19085 19101 19166 19177 19190 19325 19398 19609 20099 20111 21012 21121 21266 21358 21437 21924 21935 21968 22363 22375 22396 22917 22943 22950 22965 23099 23121 23127 24116 24571 24775 25196 26131 26292 26301 27060 27310 27532 27583 28083 28167 28479 28492 29570 29675 29963 31211 31424 32247 32594 36100 36139 36417 38763 40060 40131 40344 40479 42901 42980 44805 46964 47941 48023 48529 48595 48610 489651.1032405581798342e-24 1.1032405581798342e-24https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/245/3?format=asciiRadiodefaultJ/ApJS/245/3/table2HI 21cm line observations, column densities, and source sizesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDSource identifiermeta.id;meta.maincharz[0.017/3.8] Optical redshiftsrc.redshiftdoublee_z[9e-06/0.008]? Uncertainty in zstat.error;src.redshiftdoublenullablenu[297.5/1396] HI absorption line centroid or expected frequencyMHzem.freqdoublee_nu[0.01/3]? Uncertainty in nuMHzstat.errorfloatnullableBlue[-12690/-327]? Blue velocity range limitkm/sinstr.bandwidthintnullableRed[20/26560]? Red velocity range limitkm/sinstr.bandwidthintnullablerms[1.8/49]? Spectral rms noise in search regionstat.stdev;instr.det.noise;obs.fieldfloatnullablef_rms[R] R= Radio Frequency Interferencemeta.codecharCtnm[0.1/46.7]? Continuum flux density at expected redshifted lineJyphot.flux.density;em.radio.750-1500MHzdoublenullablee_Ctnm[2e-05/3.6]? Uncertainty in CtnmJystat.errordoublenullablel_NHIThe 3{sigma} limit flag on NHImeta.code.errorcharNHI[0.01/74]? Measured H I column density1e+20cm**-2phys.columnDensityfloatnullablee_NHI[0.4/13]? Uncertainty in NHI1e+20cm**-2stat.errorfloatnullablel_P-NHIThe 3{sigma} limit flag on P-NHImeta.code.errorcharP-NHI[0.08/81]? Previously measured HI column density1e+20cm**-2phys.columnDensityfloatnullabler_P-NHI[1/10]? Flag on P-NHI (4)meta.ref;pos.frameintnullablee_P-NHI[1.3/17]? Uncertainty in P-NHI1e+20cm**-2stat.errorfloatnullableASize[0.0004/9.2]? Largest projected angular sizearcsecphys.angSize;stat.maxfloatnullablePSize[0.001/64.5]? Linear sizekpcphys.sizedoublenullableRefc[1/17]? Continuum source characteristics reference code (5)meta.ref;pos.frameintnullableJ/ApJS/245/3/table3OH 18cm observations and column density limitsf_NOH/Tx[ab] Flag on NOH/Tx (1)meta.codecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDSource identifiermeta.id;meta.maincharz[0.15/3.8] Optical redshiftsrc.redshiftdoublenu1612[337.7/1398.8] Expected frequency of 1612MHz lineMHzem.freq;spect.linefloatBlue1612[-10741/-93]? Blue velocity range limit of 1612MHz linekm/sinstr.bandwidthintnullableRed1612[760/13121]? Red velocity range limit of 1612MHz linekm/sinstr.bandwidthintnullablerms1612[2/18]? Spectral rms noise around 1612MHz linemJystat.stdev;instr.det.noisefloatnullablef_rms1612[R] R: Radio Frequency Interferencemeta.codecharnu1667[349.3/1446.6] Expected frequency of 1667MHz lineMHzem.freq;spect.linefloatBlue1667[-10496/-83]? Blue velocity range limit of 1667MHz linekm/sinstr.bandwidthintnullableRed1667[270/12882]? Red velocity range limit of 1667MHz linekm/sinstr.bandwidthintnullablerms1667[1.5/19.1]? Spectral rms noise around 1667MHz linemJystat.stdev;instr.det.noisefloatnullablef_rms1667[R] R: Radio Frequency Interferencemeta.codecharnu1720[360.4/1492.7] Expected frequency of 1720MHz lineMHzem.freq;spect.linefloatBlue1720[-12972/-42]? Blue velocity range limit of 1720MHz linekm/sinstr.bandwidthintnullableRed1720[142/9330]? Red velocity range limit of 1720MHz linekm/sinstr.bandwidthintnullablerms1720[1.9/18.2]? Spectral rms noise around 1720MHz linemJystat.stdev;instr.det.noisefloatnullablef_rms1720[R] R: Radio Frequency Interferencemeta.codecharCntm[0.1/45]? Expected continuum flux at redshifted 1667MHz OH linemJyphot.flux.density;em.radio.1500-3000MHzdoublenullablee_Cntm[2e-05/3]? Uncertainty in CntmmJystat.errordoublenullablef_Cntm[ab] Flag on Cntm (1)meta.codecharl_NOH/TxThe 3{sigma} limit flag on NOH/Txmeta.code.errorcharNOH/Tx[0.3/1640]? Column density of expected redshifted 1670MHz OH line1e+13cm**-2.K**-1phys.columnDensityfloatnullableJ/ApJS/245/3/table1Observations of intrinsic HI and OH lines toward compact radio sourcesSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHIDisplay the HI data (link to Table 2)meta.ref.urlintnullableIDSource identifiermeta.id;meta.maincharprimaryOHDisplay the OH data (link to Table 3)meta.ref.urlintnullableRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainz[0.017/3.8] Optical redshiftsrc.redshiftdoublee_z[9e-06/0.01]? Uncertainty in zstat.error;src.redshiftdoublenullablenuHI[297/1396] Expected frequency of HI 21cm lineMHzem.freq;spect.linedoublee_nuHI[0.01/3]? Uncertainty in nuHIMHzstat.errorfloatnullableHItime[164/3583]? Total HI integration timestime.expointnullableOHtime[149/3583]? Total OH integration timestime.expointnullableClassRadio source cassification (1)meta.code.classcharr_ClassClassification reference code(s) (2)meta.ref;pos.framecharRefsp[1/5]? Previous HI spectrum reference code (3)meta.ref;pos.frameintnullableWBDisplay data from White and Becker, 1992, VIII/17, within 30"meta.ref.urlintnullableNEDNED column added by the CDSmeta.ref.urlchar