J/A+A/573/A13ivo://CDS.VizieR/J/A+A/573/A13doi:10.26093/cds/vizier.35730013CDSDias B.Barbuy B.Saviane I.Held E.V.Da Costa G.S.Ortolani S.,Vasquez S.Gullieuszik M.Katz D.2017-07-06T06:26:00Z2015-02-27T15:38:19ZCDS support team

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

cds-question@unistra.frglobular-star-clusterschemical-abundanceseffective-temperatureWe have observed almost one third of the globular clusters in the Milky Way, targeting distant and/or highly reddened objects, as well as a few reference clusters. A large sample of red giant stars was observed with FORS2 at VLT/ESO at R~2000. The method for deriving stellar parameters is presented with application to six reference clusters. We aim at deriving the stellar parameters effective temperature, gravity, metallicity, and {alpha}-element enhancement as well as the radial velocity to confirm the membership of individual stars in each cluster. We analyse the spectra collected for the reference globular clusters NGC 6528 ([Fe/H]~-0.1), NGC 6553 ([Fe/H]~-0.2), M 71 ([Fe/H]~-0.8), NGC 6558 ([Fe/H]~-1.0), NGC 6426 ([Fe/H]~-2.1), and Terzan 8 ([Fe/H]~-2.2). They cover the full range of globular cluster metallicities, and are located in the bulge, disc, and halo. Full spectrum-fitting techniques were applied by comparing each target spectrum with a stellar library in the optical region at 4560-5860{AA}. We employed the library of observed spectra MILES, and the Coelho synthetic library. We validated the method by recovering the known atmospheric parameters for 49 well-studied stars that cover a wide range in the parameter space. We adopted as final stellar parameters (effective temperatures, gravities, metallicities) the average of results using the observed and synthetic spectral libraries.2015A&A...573A..13Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/573/A13CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/573/A13https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/573/A13http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/573/A13https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/573/A13https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/573/A13http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/573/A13GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/573/A13/sample (Star-by-star coordinates, heliocentric radial velocity and atmospheric parameters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/573/A13/sample?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/573/A13/sample?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/573/A13/sample?GETtext/xml+votable180.050000true271.1807717-30.00702360.0055555555555555566/12943 28768 28778 28882 31095 31778 479033.322582951404819e-19 3.852589004194616e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/573/A13?format=asciidefaultJ/A+A/573/A13/sampleStar-by-star coordinates, heliocentric radial velocity and atmospheric parametersSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarStar identification (1)meta.id;meta.maincharRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainVmagV magnitudemagphot.mag;em.opt.VfloatV-IV-I colour indexmagphot.color;em.opt.V;em.opt.IfloatHV[-317/200] Heliocentric velocitykm/sspect.dopplerVeloc;pos.heliocentricfloatHVt[231/209]? Ca triplet heliocentric velocity (2)km/sphys.veloc;pos.heliocentricfloatnullableMmb[M] Membership (M=member)meta.code.membercharTeffaEffective temperature from MILES libraryKphys.temperature.effectiveinte_Teffarms uncertainty on TeffaKstat.errorintTeffbEffective temperature from Coelho libraryKphys.temperature.effectiveinte_Teffbrms uncertainty on TeffbKstat.errorintTeffAverage of MILES and Coelho effective temperatureKphys.temperature.effective;stat.meaninte_Teffrms uncertainty on TeffKstat.error;phys.temperature.effectiveintloggaSurface gravity from MILES librarylog(cm.s**-2)phys.gravityfloate_loggarms uncertainty on loggalog(cm.s**-2)stat.errorfloatloggbSurface gravity from Coelho librarylog(cm.s**-2)phys.gravityfloate_loggbrms uncertainty on loggblog(cm.s**-2)stat.errorfloatloggAverage of MILES and Coelho surface gravitylog(cm.s**-2)phys.gravity;stat.meanfloate_loggrms uncertainty on logglog(cm.s**-2)stat.errorfloat[Fe/H]aMetallicity from MILES librarylog(Sun)phys.abund.Fefloate_[Fe/H]arms uncertainty on [Fe/H]alog(Sun)stat.error;phys.abund.Fefloat[Fe/H]bMetallicity from Coelho librarylog(Sun)phys.abund.Fefloate_[Fe/H]brms uncertainty on [Fe/H]blog(Sun)stat.error;phys.abund.Fefloat[Fe/H]Average of MILES and Coelho metallicitylog(Sun)phys.abund.Fefloate_[Fe/H]rms uncertainty on [Fe/H]log(Sun)stat.error;phys.abund.Fefloat[Mg/Fe]Abundance [Mg/Fe] from MILES librarylog(Sun)phys.abundfloate_[Mg/Fe]rms uncertainty on [Mg/Fe]log(Sun)stat.error;phys.abundfloat[a/Fe]Abundance [{alpha}/Fe] from Coelho librarylog(Sun)phys.abundfloate_[a/Fe]rms uncertainty on [{alpha}/Fe]log(Sun)stat.error;phys.abundfloat