J/ApJ/770/138ivo://CDS.VizieR/J/ApJ/770/138doi:10.26093/cds/vizier.17700138CDSLehner N.Howk J.C.Tripp T.M.Tumlinson J.Prochaska J.X.,O'Meara J.M.Thom C.Werk J.K.Fox A.J.Ribaudo J.2017-12-07T07:27:08Z2015-02-03T13:31:47ZCDS support team

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

cds-question@unistra.frquasarsredshiftedchemical-abundancesh-i-line-emissionWe assess the metal content of the cool (~10^4^K) circumgalactic medium (CGM) about galaxies at z<~1 using an H I-selected sample of 28 Lyman limit systems (LLS; defined here as absorbers with 16.2<~logN_HI_<~18.5) observed in absorption against background QSOs by the Cosmic Origins Spectrograph on board the Hubble Space Telescope. The N_HI_ selection avoids metallicity biases inherent in many previous studies of the low-redshift CGM. We compare the column densities of weakly ionized metal species (e.g., O II, Si II, Mg II) to N_HI_ in the strongest H I component of each absorber. We find that the metallicity distribution of the LLS (and hence the cool CGM) is bimodal with metal-poor and metal-rich branches peaking at [X/H]=~-1.6 and -0.3 (or about 2.5% and 50% solar metallicities). The cool CGM probed by these LLS is predominantly ionized. The metal-rich branch of the population likely traces winds, recycled outflows, and tidally stripped gas; the metal-poor branch has properties consistent with cold accretion streams thought to be a major source of fresh gas for star forming galaxies. Both branches have a nearly equal number of absorbers. Our results thus demonstrate there is a significant mass of previously undiscovered cold metal-poor gas and confirm the presence of metal enriched gas in the CGM of z<~1 galaxies.2013ApJ...770..138Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/770/138CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/hst : HST Archived Exposures Catalog (STScI, 2007)J/MNRAS/434/1765 : Catalog of galaxies around PKS 0405-123 (Johnson+, 2013)J/ApJ/755/89 : Metallicities of damped Ly{alpha} systems (Rafelski+, 2012)J/ApJ/740/91 : Ly{alpha} & OVI in galaxies around quasars (Prochaska+, 2011)J/ApJ/736/42 : HST QSO Catalog (Ribaudo+, 2011)J/ApJS/193/28 : Galaxy survey around 20 UV-bright quasars (Prochaska+, 2011)J/ApJ/721/1 : Keck ESI observations of Ly{alpha} systems (Penprase+, 2010)J/ApJ/714/1521 : Spectroscopy of galaxies around distant QSOs (Chen+, 2010)J/ApJ/710/613 : Broad HI absorbers (Danforth+, 2010)J/ApJ/700/1299 : Gas-phase element depletions in the ISM (Jenkins, 2009)J/ApJS/182/378 : HI and OVI absorbers in nearby Universe (Wakker+, 2009)J/ApJ/676/262 : PKS1302-102 intergalactic absorption system (Cooksey+, 2008)J/ApJS/168/213 : Ionization states and cooling efficiencies (Gnat+, 2007)J/ApJ/636/610 : Damped Ly{alpha} systems at z<1.65 (Rao+, 2006)J/MNRAS/367/1261 : Redshift survey in 15 quasar fields (Morris+, 2006)J/ApJS/164/1 : IGM absorbers toward HE 0226-4110 (Lehner+, 2006)J/ApJ/617/718 : Atomic data and EW for PKS 0405-123 (Prochaska+, 2004)J/ApJ/599/116 : UV properties of absorbed quasars (Vestergaard+, 2003)J/ApJS/155/351 : Absorption toward PG 1116+215 (Sembach+, 2004)J/ApJ/513/168 : HST observations of carbon in spiral galaxies (Garnett+, 1999)J/ApJ/508/200 : QSO low-z Ly{alpha} absorbers (Tripp+, 1998)J/ApJ/475/469 : Composite HST Spectrum of Quasars (Zheng+ 1997)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/770/138https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/770/138http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/770/138https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/770/138https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/770/138http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/770/138GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/770/138/table1 (Summary of the metallicity of the Lyman limit systems (LLS), super-LLS, and DLA at z>~1)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/770/138/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/770/138/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/770/138/table1?GETtext/xml+votable180.050000true145.88175145.52541190.0055555555555555566/2 579 5773 6104 7381 7460 8282 8952 9252 9440 9457 9753 9817 10061 10098 10298 10432 10517 10571 10602 10659 10940 11723 12740 17730 17757 17818 17827 17833 17835 18096 18601 18772 18790 19483 20032 21180 22659 23016 25285 25742 25935 25940 26196 26245 26255 26267 26878 27030 27034 27037 27215 27248 27376 27526 27720 27739 28356 31686 32961 33796 33950 35205 36086 37385 40479 44028https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/770/138?format=asciiOpticalRadiodefaultJ/ApJ/770/138/table1Summary of the metallicity of the Lyman limit systems (LLS), super-LLS, and DLA at z>~1SimbadNameSimbad column added by the CDSmeta.idcharQSOQSO namemeta.id;meta.maincharzabs[0.006/1.1] Redshift of the absorbersrc.redshiftfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTypeObject type: LLS, SLLS or DLA (1)src.classcharNaNumber of absorbers for this quasarmeta.numberintnullableNnNumber of column densities measures for this absorber (table 2)meta.numberintnullablelogNHI[16.1/21.7] HI column densitylog(cm**-2)phys.columnDensityfloatE_logNHI[0.02/0.3] Positive error on logNHIlog(cm**-2)stat.error;stat.maxfloate_logNHI[0.02/0.3] Negative error on logNHIlog(cm**-2)stat.errorfloatl_[X/H]Limit flag on [X/H]meta.code.error;phys.abundchar[X/H][-2/0.7] Metallicity (2)log(Sun)phys.abundfloatu_[X/H][:] Uncertainty flag on [X/H] (3)meta.code.error;phys.abundchare_[X/H]? Uncertainty on [X/H]log(Sun)stat.error;phys.abundfloatnullablel_logU[<=> ] Limit flag on logUmeta.code.errorcharlogU[-5.2/-2]? Log of ionization parameter U (3)phys.ionizParam.radfloatnullablel_rhoLimit flag on rhometa.code.errorcharrho[6/3238]? Impact parameter {rho} (3)kpcsrc.impactParamintnullableRefReference(s) (see refs.dat file)meta.ref;pos.framecharn_RefRemarks on absorber (4)meta.notechar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/ApJ/770/138/table2Adopted column densitiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintQSOQSO name (1)meta.id;meta.maincharzabsRedshift from absorption linessrc.redshiftfloatr_zabs[bc] Origin of z (2)meta.ref;pos.framecharIonSpecies identifierphys.atmol.ionStagecharl_logNLimit flag on logN (3)meta.code.errorlogNLog column densitylog(cm**-2)phys.columnDensityfloatE_logN? Uncertainty in logN (4)log(cm**-2)stat.error;stat.maxfloatnullablee_logN? Lower limit uncertainty in logN (4)log(cm**-2)stat.errorfloatnullableu_logN[:] Uncertainty flag in logNmeta.code.errorcharv1Lower velocity of the integration of the N_a_(v) profilekm/sphys.velocintv2Upper velocity of the integration of the N_a_(v) profilekm/sphys.velocintJ/ApJ/770/138/refsReferencesRefReference codemeta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBibCodeBibcodemeta.bib.bibcodecharAutAuthor's name(s)meta.bib.authorcharCommComment (VizieR catalog reference)meta.notechar