J/MNRAS/465/588ivo://CDS.VizieR/J/MNRAS/465/588doi:10.26093/cds/vizier.74650588CDSDutta R.Srianand R.Gupta N.Momjian E.Noterdaeme P.Petitjean P.,Rahmani H.2024-08-17T20:17:24Z2018-09-07T10:59:42ZCDS support team

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

cds-question@unistra.frquasarsgalaxiesh-i-line-emissionredshiftedWe present the results from our survey of HI 21-cm absorption, using Giant Metrewave Radio Telescope, Very Large Array and Westerbork Radio Synthesis Telescope, in a sample of 55 z<0.4 galaxies towards radio sources with impact parameters (b) in the range ~0-35kpc. In our primary sample (defined for statistical analyses) of 40 quasar-galaxy pairs, probed by 45 sightlines, we have found seven HI 21-cm absorption detections, two of which are reported here for the first time. Combining our primary sample with measurements having similar optical depth sensitivity ({int}{tau}dv<=0.3km/s) from the literature, we find a weak anti-correlation (rank correlation coefficient =-0.20 at 2.42{sigma} level) between {int}{tau}dv and b, consistent with previous literature results. The covering factor of HI 21-cm absorbers (C21) is estimated to be 0.24^+0.12^_-0.08_ at b<=15kpc and 0.06^+0.09^_-0.04_ at b=15-35kpc. {int}{tau}dv and C_21_ show similar declining trend with radial distance along the galaxy's major axis and distances scaled with the effective HI radius. There is also tentative indication that most of the HI 21-cm absorbers could be co-planar with the extended HI discs. No significant dependence of {int}{tau}dv and C_21_ on galaxy luminosity, stellar mass, colour and star formation rate is found, though the HI 21-cm absorbing gas cross-section may be larger for the luminous galaxies. The higher detection rate (by a factor of ~4) of HI 21-cm absorption in z<1 damped Lyman-{alpha} systems compared to the quasar-galaxy pairs indicates towards small covering factor and patchy distribution of cold gas clouds around low-z galaxies.2017MNRAS.465..588Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/465/588CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/465/588https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/465/588http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/465/588https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/465/588https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/465/588http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/465/588GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/465/588/tablea1 (Details of the QGPs observed by us)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/465/588/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/465/588/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/465/588/tablea1?GETtext/xml+votable180.050000true10.3587917-1.71822220.0055555555555555566/4229 4247 4353 4383 4421 4524 4655 4800 4990 5407 5662 6623 7226 8229 8335 8780 9237-9238 9252 9353 9430 9462 9882 10309 10328 10401 10798 10815 10921 11639 11914 17834 17979 18112 18540 18851 22013 25972 26078 26209 26334 26385 26983 27045 27083 27378 27955 28518 28622 30039 31463 31477 31599https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/465/588?format=asciiRadiodefaultJ/MNRAS/465/588/tablea1Details of the QGPs observed by usType[QGU] Type of radio source (G3)spect.dopplerVeloc.radio;em.radiocharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSample[PSM] Sample (G1)src.samplecharQGPQGP name (JHHMM+DDMM)meta.id;meta.maincharm_QGPMultiplicity index on QGP (G2)meta.code.multipcharRNameRadio source name (JHHMMSS.ss+DDMMSS.s)meta.idcharl_zrad[>= ] Limit flag on zradmeta.code.errorcharzrad? Redshift of radio sourcesrc.redshift;pos.heliocentricfloatnullablen_zrad[ab] Note on zrad (3)meta.notecharMorph[CR] Morphology of radio source at arcsecond-scale (G4)meta.notecharGalaxyGalaxy name (JHHMMSS.ss+DDMMSS.s)meta.idcharzgal? Galaxy redshiftsrc.redshift;pos.heliocentricdoublenullabler_zgal? Reference for zgal (6)meta.ref;pos.distance;pos.frameintnullableg-r? Rest-frame SDSS g-r colour of galaxymagphot.color;em.opt.B;em.opt.RfloatnullablelogM*? log of stellar mass of galaxy from kcorrect (Blanton & Roweis, 2007AJ....133..734B)log(solMass)phys.massfloatnullablelogLB? log of B-band luminositylog(solLum)phys.luminosity;em.opt.Bfloatnullablel_bLimit flag on bmeta.code.errorcharbProjected separation or impact parameter between radio sightline and centre of galaxykpcpos.distancefloati? Galaxy inclinationdegsrcintnullablephi? Orientation of radio sightline with respect to galaxy's major axisphys.sizeintnullable_RAPosition from radio name (right ascension part)degpos.eq.ra;meta.main_DEPosition from radio name (declination part)degpos.eq.dec;meta.mainJ/MNRAS/465/588/tableb1Details of the QGPs searched for HI 21-cm absorption in the literature that are included in this workType[QGU] Type of radio source (G3)spect.dopplerVeloc.radio;em.radiocharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRNameRadio source name (JHHMMSS.ss+DDMMSS.s)meta.idcharzrad? Redshift of radio sourcesrc.redshift;pos.heliocentricfloatnullablen_zrad[p] Note on zrad, p for photometric redshiftmeta.notecharMorph[CR] Morphology of radio source at arcsecond-scale (G4)meta.notecharGalaxyGalaxy name (JHHMMSS.ss+DDMMSS.s)meta.idcharzgal? Galaxy redshiftsrc.redshift;pos.heliocentricdoublenullableg-r? Rest-frame SDSS g-r colour of galaxymagphot.color;em.opt.B;em.opt.RfloatnullablelogM*? log of stellar mass of galaxy from kcorrect (Blanton & Roweis, 2007AJ....133..734B)log(solMass)phys.massfloatnullablelogLB? log of B-band luminositylog(solLum)phys.luminosity;em.opt.BfloatnullablebProjected separation or impact parameter between radio sightline and centre of galaxykpcpos.distancefloati? Galaxy inclinationdegsrcintnullablephi? Orientation of radio sightline with respect to galaxy's major axisdegphys.angSize;em.radiointnullablel_Itdv3s[<= ] Limit flag on Itdv3smeta.code.errorcharItdv3s3{sigma} upper limit on integrated HI 21-cm optical depth from spectra smoothed to 10km/skm/sphys.absorption.opticalDepthfloatItdv? Integrated HI 21-cm optical depth in the case of detections at the observed spectral resolutionkm/sphys.absorption.opticalDepthfloatnullablen_Itdv[b] Note on Itdv (1)meta.notecharRefReference for the HI 21-cm optical depth measurements (2)meta.ref;phys.absorption.opticalDepthintJ/MNRAS/465/588/tablec1Details of the galaxy spectra obtained using SALTrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalaxyGalaxy name (JHHMMSS.ss+DDMMSS.s)meta.id;meta.maincharzgalGalaxy redshiftsrc.redshiftfloate_zgalrms uncertainty on zgalstat.error;pos.distance;pos.cartesian.zfloatEmLinesEmission lines detected in the SALT spectrummeta.id;spect.lineAbsLinesAbsorption lines detected in the SALT spectrummeta.id;spect.lineJ/MNRAS/465/588/tabled1Radio observation log of the sources observed by usrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSample[PSM] Sample (G1)src.samplecharRNameRadio source name (JHHMMSS.ss+DDMMSS.s)meta.idcharGalaxyGalaxy name (JHHMMSS.ss+DDMMSS.s)meta.idcharzgal? Galaxy redshiftsrc.redshiftdoublenullableTelTelescope used for radio observationinstr.setupcharDateDate of observationtime.epochnullabledv? Spectral resolution in km/s per channelkm/sspectfloatnullableTimeonTime on sourcehtime.epochfloatBeam1? Size of the restoring beam of the continuum imagearcsecphys.angSize;instr.beamfloatnullableBeam2? Size of the restoring beam of the continuum imagearcsecphys.angSize;instr.beamfloatnullableSpres1? Spatial resolution corresponding to the beam size at the redshift of the galaxykpcpos.angResolution;instr.beamfloatnullableSpres2? Spatial resolution corresponding to the beam size at the redshift of the galaxykpcpos.angResolution;instr.beamfloatnullableJ/MNRAS/465/588/tablee1Parameters derived from radio observationsRefReferences (2)meta.refintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSample[PSM] Sample (G1)src.samplecharQGPQGP name (JHHMM+DDMM)meta.id;meta.maincharm_QGPMultiplicity index on QGP (G2)meta.code.multipcharSpeakPeak flux densitymJy/beamphot.flux.density;em.radio.750-1500MHzintdvSpectral resolution in km/s per channelkm/sspectfloatrmsSpectral rms (1)mJy/beaminstr.det.noisefloatsigmatauStandard deviation of the HI 21-cm optical depth (1)stat.stdev;phys.absorption.opticalDepthfloatsigmap? Maximum HI 21-cm optical depth in the case of HI 21-cm detections (1)stat.stdev;phys.absorption.opticalDepthfloatnullablel_Itdv3s[<= ] Limit flag on Itdv3smeta.code.errorcharItdv3s3{sigma} upper limit on integrated HI 21-cm optical depth from spectra smoothed to 10km/skm/sphys.absorption.opticalDepthfloatItdv? Integrated HI 21-cm optical depth in the case of detections at the observed spectral resolution (1)km/sphys.absorption.opticalDepthfloatnullablee_Itdv? rms uncertainty on Idtvkm/sstat.errorfloatnullable