J/MNRAS/452/217ivo://CDS.VizieR/J/MNRAS/452/217doi:10.26093/cds/vizier.74520217CDSCrighton N.H.M.Murphy M.T.Prochaska J.X.Worseck G.Rafelski M.,Becker G.D.Ellison S.L.Fumagalli M.Lopez S.Meiksin A.O'meara J.M.2024-08-15T20:14:19Z2016-02-23T08:22:53ZCDS support team

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

cds-question@unistra.frquasarsredshiftedWe present the largest homogeneous survey of z>4.4 damped Ly{alpha} systems (DLAs) using the spectra of 163 QSOs that comprise the Giant Gemini GMOS (GGG) survey. With this survey we make the most precise high-redshift measurement of the cosmological mass density of neutral hydrogen, Omega_HI_. At such high redshift, important systematic uncertainties in the identification of DLAs are produced by strong intergalactic medium absorption and QSO continuum placement. These can cause spurious DLA detections, result in real DLAs being missed or bias the inferred DLA column density distribution. We correct for these effects using a combination of mock and higher resolution spectra, and show that for the GGG DLA sample the uncertainties introduced are smaller than the statistical errors on Omega_HI_. We find Omega_HI_=0.98^+0.20^_-0.18_x10^-3^ at <z>=4.9, assuming a 20 percent contribution from lower column density systems below the DLA threshold. By comparing to literature measurements at lower redshifts, we show that Omega_HI_ can be described by the functional form Omega_HI_(z){prop.to}(1+z)^0.4^. This gradual decrease from z=5 to 0 is consistent with the bulk of HI gas being a transitory phase fuelling star formation, which is continually replenished by more highly ionized gas from the intergalactic medium and from recycled galactic winds.2015MNRAS.452..217Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/452/217CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/445/1745 : Giant Gemini GMOS survey. I. (Worseck+, 2014)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/452/217https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/452/217http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/452/217https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/452/217https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/452/217http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/452/217GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/452/217/table1 (Higher resolution spectra used in our analysis)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/452/217/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/452/217/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/452/217/table1?GETtext/xml+votable180.050000true1.95483330.68877780.005555555555555556Cone search capability for table J/MNRAS/452/217/table3 (Redshift limits used to calculate the redshift search path for DLAs for each QSO)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/452/217/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/452/217/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/452/217/table3?GETtext/xml+votable180.050000true2.813458314.76716670.0055555555555555566/4101 4157 4227 4242 4352 4466 4475 4626 4641 4660 4729 4754 4872 4905 4931 5065 5098 5121 5170 5186 5229-5230 5295 5331 5400 5407 5458 5537 5710 5723 5752 5779 5923 5935 6071 6096 6112 6129 6133 6238 6415 6500 6552 6917 7183 7197 7293 7378 7464 7478 7522 8211 8224 8227 8238 8301 8319 8321 8323 8354 8481 8486 8515 8542 8553 8562 8638 8670 8672 8722 8819 8829 8846 9084 9095 9222 9273 9275 9278 9285 9412 9740 9748 9855 9902 9966 10123 10193 10336 10451 10497 10512 10520 10528 10609 10656 10665 10686 10734 10783 10803 10933 10939 10988 11027 11115 11121 11143 11165 11267 11287 11842 11945 17239 17470 17812 18018 18032 18091 18627 18882 18945 19028 19033 19046 19676 19690 20010 22006 23191 25911 25938 25977 26031 26037 26080 26098 26221 26233 26280 26351 26542 26567-26568 26990 27118 27135 27225 27359 27452 27508 27615 27696 27708 27828 27833 27870 27876 27901 27974 28008 28023 28027 28067 28080 28119 28294 28401 28419 28530 28560 28572 28612 28614 30037 31529 31629 32438 36725 36792https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/452/217?format=asciidefaultJ/MNRAS/452/217/table1Higher resolution spectra used in our analysisSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSDSSQSO SDSS name (JHHMMSS.ss+DDMMSS.s)meta.id;meta.maincharzemQSO emission redshiftsrc.redshiftfloatInstInstrument used to take the spectruminstr.setupcharS/NMedian S/N per pixel over rest-frame wavelengths 1240-1280{AA}stat.snrfloatGGG?[Yes/No ] Whether the QSO is in the GGG samplesrc.samplecharSloanDisplay the SDSS data for this quasarmeta.ref.urlchar_RARight ascension (derived from SDSS) for Eq=J2000degpos.eq.ra;meta.main_DEDeclination (derived from SDSS) for Eq=J2000degpos.eq.dec;meta.mainJ/MNRAS/452/217/table3Redshift limits used to calculate the redshift search path for DLAs for each QSOSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSDSSQSO SDSS name (JHHMMSS.ss+DDMMSS.s)meta.id;meta.maincharzminStart redshift for the DLA searchsrc.redshiftfloatzmaxEnd redshift for the DLA searchsrc.redshiftfloatzemQSO emission redshiftsrc.redshiftfloatSloanDisplay the SDSS data for this quasarmeta.ref.urlchar_RARight ascension (derived from SDSS) for Eq=J2000degpos.eq.ra;meta.main_DEDeclination (derived from SDSS) for Eq=J2000degpos.eq.dec;meta.main