J/MNRAS/435/482ivo://CDS.VizieR/J/MNRAS/435/482doi:10.26093/cds/vizier.74350482CDSJorgenson R.A.Murphy M.T.Thompson R.2024-08-06T20:17:20Z2014-10-09T16:09:36ZCDS support team

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

cds-question@unistra.frquasarsredshiftedline-intensitieschemical-abundancesWe present the chemical abundance measurements of the first large, medium-resolution, uniformly selected damped Lyman {alpha} system (DLA) survey. The sample contains 99 DLAs towards 89 quasars selected from the SDSS DR5 DLA sample in a uniform way. We analyse the metallicities and kinematic diagnostics, including the velocity width of 90 percent of the optical depth, {Delta}V_90_, and the equivalent widths of the SiII {lambda}1526 (W}{lambda}1526), CIV {lambda}1548 and MgII {lambda}2796 transitions. To avoid strong line-saturation effects on the metallicities measured in medium-resolution spectra (FWHM~71km/s), we derived metallicities from metal transitions which absorbed at most 35 percent of the quasar continuum flux. We find the evolution in cosmic mean metallicity of the sample, <Z>=(-0.04+/-0.13)z-(1.06+/-0.36), consistent with no evolution over the redshift range z~[2.2, 4.4], but note that the majority of our sample falls at z~[2.2, 3.5]. The apparent lack of metallicity evolution with redshift is also seen in a lack of evolution in the median {Delta}V_90_ and W{lambda}1526 values. While this result may seem to conflict with other large surveys that have detected significant metallicity evolution, such as Rafelski et al. who found <Z>=(-0.22+/-0.03)z-(0.65+/-0.09) over z~[0, 5], several tests show that these surveys are not inconsistent with our new result. However, over the smaller redshift range covered by our uniformly selected sample, the true evolution of the cosmic mean metallicity in DLAs may be somewhat flatter than the Rafelski et al. (2012ApJ...755...89R, Cat. J/ApJ/755/89) estimate.2013MNRAS.435..482Jhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/435/482CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/other/PASA/19.455 : Damped Lyman alpha absorption of QSOs (Curran+, 2002)J/MNRAS/346/1103 : Redshifts of damped Ly{alpha} absorbers (Peroux+, 2003)J/MNRAS/354/L31 : SDSS DR2 QSO and DLA properties (Murphy+, 2004)J/A+A/473/791 : CIV absorption in DLAs and sub-DLAs systems (Fox+, 2007)J/MNRAS/392/998 : Damped Lyman{alpha} systems (Ellison+, 2009)J/A+A/508/133 : DLA absorbers in z>4 QSOs (Guimaraes+, 2009)J/A+A/566/A24 : Extremely strong DLA systems (Noterdaeme+, 2014)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/435/482https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/435/482http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/435/482https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/435/482https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/435/482http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/435/482GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/435/482/table1 (DLA (damped Lyman {alpha}) Sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/435/482/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/435/482/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/435/482/table1?GETtext/xml+votable180.050000true2.813494214.76715780.0055555555555555566/523 4125 4167 4356 12552 17244 17299 17317 17518 17743 17751 18007 18405 18537 18582 18769 18857 19087 19374 19408 19411 19667 19676 19688 20016 23190 25821 25844 25937 25943 25987 26014 26088 26188 26206 26209 26236 26258 26264 26286 26301 26381 26398 26479 26553 26968 27001 27043 27053 27129 27237 27365 27398 27430 27450 27460 27473 27497 27508 27518 27537 27542 27561 27577 27599 27649 27667 27687 27693 27743 27747 27749 27760 27777 27799 27838 27907 27909 27922 27943 28171 28174 28197 31451 36792 49086 49121https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/435/482?format=asciiOpticaldefaultJ/MNRAS/435/482/table1DLA (damped Lyman {alpha}) SamplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintQuasarQuasar name (JHHMM+DDMM)meta.id;meta.maincharzem[2.4/5.0] Emission redshiftsrc.redshiftfloatzabs[2.2/4.4] Absorption redshiftsrc.redshiftfloatlogN(HI)HI column densitylog(cm**-2)phys.columnDensityfloatE_logN(HI)Error on HI (upper value)log(cm**-2)stat.error;stat.maxfloate_logN(HI)Error on HI (lower value)log(cm**-2)stat.errorfloatDV90Velocity width of 90% of the optical depthkm/sspect.line.widthintW1526? SiII 1526{AA} rest equivalent width (1)0.1nmspect.line.eqWidthfloatnullablee_W1526? rms uncertainty on W15260.1nmstat.errorfloatnullableW1548? CIV 1548{AA} rest equivalent width (1)0.1nmspect.line.eqWidthfloatnullablee_W1548? rms uncertainty on W15480.1nmstat.errorfloatnullable[M/H]Metallicitylog(Sun)phys.abund.Zfloate_[M/H]rms uncertainty on [M/H]log(Sun)stat.error;phys.abundfloatn_[M/H]Flag describing metallicity measurement (2)meta.noteint[Fe/H]Iron abundancelog(Sun)phys.abund.Fefloate_[Fe/H]rms uncertainty on [Fe/H]log(Sun)stat.error;phys.abund.Fefloatn_[Fe/H]Flag describing Fe Measurement (3)meta.noteintInstInstrument code (4)meta.code;instrinttexpExposure timestime.duration;obs.exposureintProgVLT programme ID numbers (5)meta.id;obscharDR5Details from the SDSS-DR5 photometric catalog (II/276)meta.ref.urlcharSimbadNameSimbad column added by the CDSmeta.idchar_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.main