J/A+A/601/A96ivo://CDS.VizieR/J/A+A/601/A96doi:10.26093/cds/vizier.36010096CDSLarsen S.S.Brodie J.P.Strader J.2017-05-12T15:34:30Z2017-05-10T08:45:06ZCDS support team

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

cds-question@unistra.frmilky-way-galaxyglobular-star-clustersmetallicityspectroscopyWe test the performance of our analysis technique for integrated-light spectra by applying it to seven well-studied Galactic GCs that span a wide range of metallicities. Integrated-light spectra were obtained by scanning the slit of the UVES spectrograph on the ESO Very Large Telescope across the half-light diameters of the clusters. We modelled the spectra using resolved Hubble Space Telescope colour-magnitude diagrams (CMDs), as well as theoretical isochrones, in combination with standard stellar atmosphere and spectral synthesis codes. The abundances of Fe, Na, Mg, Ca, Ti, Cr, and Ba were compared with literature data for individual stars in the clusters. The typical differences between iron abundances derived from our integrated-light spectra and those compiled from the literature are less than 0.1 dex. A larger difference is found for one cluster (NGC 6752), and is most likely caused primarily by stochastic fluctuations in the numbers of bright red giants within the scanned area. As expected, the alpha-elements (Ca, Ti) are enhanced by about 0.3 dex compared to the Solar-scaled composition, while the [Cr/Fe] ratios are close to Solar. When using up-to-date line lists, our [Mg/Fe] ratios also agree well with literature data. Our [Na/Fe] ratios are, on average, 0.08-0.14 dex lower than average values quoted in the literature, and our [Ba/Fe] ratios may be overestimated by 0.20-0.35 dex at the lowest metallicities. We find that analyses based on theoretical isochrones give very similar results to those based on resolved CMDs. Overall, the agreement between our integrated-light abundance measurements and the literature data is satisfactory. Refinements of the modelling procedure, such as corrections for stellar evolutionary and non-LTE effects, might further reduce some of the remaining offsets.2017A&A...601A..96Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/601/A96CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/601/A96https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/601/A96http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/601/A96https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/601/A96https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/601/A96http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/601/A96GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/601/A96/clusters (List of studied clusters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/601/A96/clusters?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/601/A96/clusters?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/601/A96/clusters?GETtext/xml+votable180.050000true6.0223333-72.08144440.0055555555555555566/12405 31019 33321 33330 42314 47125 48434https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/601/A96?format=asciiOpticaldefaultJ/A+A/601/A96/clustersList of studied clustersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintClusterCluster namemeta.id;meta.maincharRAJ2000Simbad right ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Simbad declination (J2000.0)pos.eq.dec;meta.mainFileNameName of the table with individual abundancesmeta.id;phys.abund;meta.tablecharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/A+A/601/A96/tablea2Abundances for NGC 362recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintElementElement ratiophys.atmol.element;arith.ratiocharlambda1Starting wavelength of spectral window0.1nmem.wlfloatlambda2Ending wavelength of spectral window0.1nmem.wlfloatAbdAbundance (dex)phys.abundfloate_AbdAbundance error (dex)stat.errorfloatJ/A+A/601/A96/tablea3Abundances for NGC 6254recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintElementElement ratiophys.atmol.element;arith.ratiocharlambda1Starting wavelength of spectral window0.1nmem.wlfloatlambda2Ending wavelength of spectral window0.1nmem.wlfloatAbdAbundance (dex)phys.abundfloate_AbdAbundance error (dex)stat.errorfloatJ/A+A/601/A96/tablea6Abundances for NGC 7078recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintElementElement ratiophys.atmol.element;arith.ratiocharlambda1Starting wavelength of spectral window0.1nmem.wlfloatlambda2Ending wavelength of spectral window0.1nmem.wlfloatAbdAbundance (dex)phys.abundfloate_AbdAbundance error (dex)stat.errorfloatJ/A+A/601/A96/tablea7Abundances for NGC 7099recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintElementElement ratiophys.atmol.element;arith.ratiocharlambda1Starting wavelength of spectral window0.1nmem.wlfloatlambda2Ending wavelength of spectral window0.1nmem.wlfloatAbdAbundance (dex)phys.abundfloate_AbdAbundance error (dex)stat.errorfloatJ/A+A/601/A96/tablea4Abundances for NGC 6388recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintElementElement ratiophys.atmol.element;arith.ratiocharlambda1Starting wavelength of spectral window0.1nmem.wlfloatlambda2Ending wavelength of spectral window0.1nmem.wlfloatAbdAbundance (dex)phys.abundfloate_AbdAbundance error (dex)stat.errorfloatJ/A+A/601/A96/tablea1Abundances for NGC 104ElementElement ratiophys.atmol.element;arith.ratiocharrecnoRecord number assigned by the VizieR team. 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