J/MNRAS/445/2061ivo://CDS.VizieR/J/MNRAS/445/2061doi:10.26093/cds/vizier.74452061CDSLiang C.J.Chen H.-W.2024-08-14T20:18:17Z2015-10-09T15:49:03ZCDS support team

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

cds-question@unistra.frquasarsgalaxiesline-intensitiesThis paper presents an absorption-line study of the multiphase circumgalactic medium (CGM) based on observations of Ly{alpha}, CII, CIV, SiII, SiIII, and SiIV absorption transitions in the vicinities of 195 galaxies at redshift z<0.176. The galaxy sample is established based on a cross-comparison between public galaxy and quasi-stellar object (QSO) survey data and is characterized by a median redshift of <z>=0.041, a median projected distance of <d>=362kpc to the sightline of the background QSO, and a median stellar mass of log(M_star_/M_{sun}_)=9.7+/-1.1. Comparing the absorber features identified in the QSO spectra with known galaxy properties has led to strong constraints for the CGM absorption properties at z<~0.176. First, abundant hydrogen gas is observed out to d~500kpc, well beyond the dark matter halo radius R_h_ of individual galaxies, with a mean covering fraction of ~60 percent. In contrast, no heavy elements are detected at d>~0.7R_h_ from either low-mass dwarfs or high-mass galaxies. The lack of detected heavy elements in low- and high-ionization states suggests that either there exists a chemical enrichment edge at d~0.7R_h_ or gaseous clumps giving rise to the observed absorption lines cannot survive at these large distances. Considering all galaxies at d>R_h_ leads to a strict upper limit for the covering fraction of heavy elements of ~3% (at a 95% confidence level) over d=(1-9)R_h_. At d<R_h_, differential covering fraction between low- and high-ionization gas is observed, suggesting that the CGM becomes progressively more ionized from d<0.3R_h_ to larger distances. Comparing CGM absorption observations at low and high redshifts shows that at a fixed fraction of R_h_ the CGM exhibits stronger mean absorption at z=2.2 than at z~0, and that the distinction is most pronounced in low-ionization species traced by CII and SiII absorption lines. We discuss possible pseudo-evolution of the CGM as a result of misrepresentation of halo radius, and present a brief discussion on the implications of these findings.2014MNRAS.445.2061Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/445/2061CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/445/2061https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/445/2061http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/445/2061https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/445/2061https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/445/2061http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/445/2061GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/445/2061/galaxies (Summary of galaxy properties (table1) and derived halo absorption properties (table4))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/445/2061/galaxies?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/445/2061/galaxies?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/445/2061/galaxies?GETtext/xml+votable180.050000true1.4378119416.148126940.005555555555555556Cone search capability for table J/MNRAS/445/2061/table2 (Summary of observations of QSOs)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/445/2061/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/445/2061/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/445/2061/table2?GETtext/xml+votable180.050000true1.4968169416.1636150.0055555555555555566/0 4195 4204 4256 4807 4821 4823-4824 4939 4961 4966 4992 5215 5244 5246 5262-5263 5274 5409 5413 5480-5481 5529 5687 5731 5737 5759 5814 5817 5820 5822 5861 5974 5980 6020-6021 6081 6087 6093 6104 6223 6488-6489 6557 6606 7277 7281 7460-7461 7508-7510 7896 8017 8282 8935 8952 9011 9018 9031 9042 9186 9419 9440 9457 9753 9755 9817 10217 10220 10432-10433 10463 10517 10578 10602-10603 10634 10656 10753 10764 10940 10965 10969 11014 11021 11208-11210 11217 11219 11396 11409 15351 16894 17748 17772 18601 18770 19700 22659 23060 25599 25742 25932-25933 26017 26019 26258-26259 26292 26396 26859 26965 27001 27006 27023 27044 27206 27229 27250 27254 27295 27338 27376 27378 27526 27528 27862 28201 28203 28355-28356 28395-28396 28401 28403 28446 28468 28470-28471 28519 28527 28546 28589 28603 28636 32961 33950-33951 36785 36788 47014https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/445/2061?format=asciidefaultJ/MNRAS/445/2061/galaxiesSummary of galaxy properties (table1) and derived halo absorption properties (table4)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalaxyGalaxy namemeta.id;meta.maincharRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainzsp[0.002/0.18] Spectroscopic redshiftsrc.redshiftdoublelog(SFR)? SFR derived from GALEX NUV band (1)log(solMass.yr**-1)phys.SFRfloatnullablelog(M*)Stellar masslog(solMass)phys.massfloatlog(Mh)Halo mass (2)log(solMass)phys.massfloatRh[23/391] Halo radius (2)kpcphys.size.radiusfloatn_Rh[0/1] How the halo parameters are derived (2)meta.notecharrMAGAbsolute r band magnitude in SDSS (3)magphys.magAbs;em.opt.RfloatQSOClosest QSOs on the line of sightmeta.ref.urlcharSep[29/9198] Angular separation QSO-galaxyarcsecpos.angDistancefloatd[32/499] Impact parameter (projected distance)kpcpos.distancefloatzLya[0/0.18]? Redshift of Ly{alpha} detectionsrc.redshift;pos.heliocentricfloatnullablel_EW(Lya)[<= ] Limit flag on EW(Lya) (2{sigma})meta.code.errorEW(Lya)[8/1397]? Ly{alpha} equivalent width (1215{AA}) (4)0.1pmspect.line.eqWidthintnullablee_EW(Lya)[3/94]? rms uncertainty on EW(Lya)0.1pmstat.errorintnullablel_EW(1206)[<= ] Limit flag on EW(1206) (2{sigma})meta.code.errorEW(1206)[1/290]? SiIII 1206{AA} equivalent width (4)0.1pmspect.line.eqWidthintnullablee_EW(1206)[2/12]? rms uncertainty on EW(1206)0.1pmstat.errorintnullablel_EW(1260)[<= ] Limit flag on EW(260) (2{sigma})meta.code.errorEW(1260)[2/146]? SiII 1260{AA} equivalent width (4)0.1pmspect.line.eqWidthintnullablee_EW(1260)[2/8]? rms uncertainty on EW(1260)0.1pmstat.errorintnullablel_EW(1393)[<= ] Limit flag on EW(1393) (2{sigma})meta.code.errorEW(1393)[3/166]? SiIV 1393{AA} equivalent width (4)0.1pmspect.line.eqWidthintnullablee_EW(1393)[4/16]? rms uncertainty on EW(1393)0.1pmstat.errorintnullablel_EW(1334)[<= ] Limit flag on EW(1334) (2{sigma})meta.code.errorEW(1334)[2/221]? CII 1334{AA} equivalent width (4)0.1pmspect.line.eqWidthintnullablee_EW(1334)[4/19]? rms uncertainty on EW(1334)0.1pmstat.errorintnullablel_EW(1548)[<= ] Limit flag on EW(1548) (2{sigma})meta.code.errorEW(1548)[6/586]? CIV 1548{AA} equivalent width (4)0.1pmspect.line.eqWidthintnullablee_EW(1548)[4/33]? rms uncertainty on EW(1548)0.1pmstat.errorintnullableJ/MNRAS/445/2061/table2Summary of observations of QSOsSimbadNameSimbad column added by the CDSmeta.idcharQSOQSO Namemeta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNgGalaxy on the same line of sightmeta.ref.urlintnullableRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainzsp[0.05/1.5] Spectroscopic redshiftsrc.redshiftdoublePID[8015/12264] Program IDmeta.idintS/N1[2/29]? Median signal-to-noise in COS(G130M grating) (1150-1450{AA})em.wl.central;stat.medianintnullableS/N2[2/20]? Median signal-to-noise in COS(G160M grating) (1450-1750{AA})em.wl.central;stat.medianintnullableS/N3[5/48]? Median signal-to-noise in STIS (1200-1700{AA})em.wl.central;stat.medianintnullable