J/ApJ/735/55ivo://CDS.VizieR/J/ApJ/735/55doi:10.26093/cds/vizier.17350055CDSColucci J.E.Bernstein R.A.Cameron S.A.McWilliam A.2017-10-13T15:41:46Z2013-01-16T11:40:17ZCDS support team

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

cds-question@unistra.frchemical-abundancesglobular-star-clustersmagellanic-cloudsline-intensitiesIn this paper, we refine our method for the abundance analysis of high-resolution spectroscopy of the integrated light of unresolved globular clusters (GCs). This method was previously demonstrated for the analysis of old (>10Gyr) Milky Way (MW) GCs. Here, we extend the technique to young clusters using a training set of nine GCs in the Large Magellanic Cloud. Depending on the signal-to-noise ratio of the data, we use 20-100 Fe lines per cluster to successfully constrain the ages of old clusters to within a ~5Gyr range, the ages of ~2Gyr clusters to a 1-2Gyr range, and the ages of the youngest clusters (0.05-1Gyr) to a ~200Myr range. We also demonstrate that we can measure [Fe/H] in clusters with any age less than 12Gyr with similar or only slightly larger uncertainties (0.1-0.25dex) than those obtained for old MW GCs (0.1dex); the slightly larger uncertainties are due to the rapid evolution in stellar populations at these ages. In this paper, we present only Fe abundances and ages. For several of the clusters in this sample, there are no high-resolution abundances in the literature from individual member stars; our results are the first detailed chemical abundances available.2011ApJ...735...55Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/735/55CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/717/277 : Chemical composition of LMC clusters (Mucciarelli+, 2010)J/ApJ/695/L134 : Chemical anomalies in old LMC clusters (Mucciarelli+, 2009)J/ApJ/704/385 : M31 integrated light abundances (Colucci+, 2009)J/AJ/136/375 : Chemical composition of LMC red giants (Mucciarelli+, 2008)J/MNRAS/386/1380 : BVRI photometry of LMC star clusters (Kumar+, 2008)J/AJ/132/1630 : CaII spectroscopy in Magellanic Cloud clusters (Grocholski+,J/MNRAS/300/665 : HST Photometry of LMC Old Globular Clusters (Olsen+, 1998)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/735/55https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/735/55http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/735/55https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/735/55https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/735/55http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/735/55GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/735/55/table1 (LMC cluster sample (9 GCs))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/735/55/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/735/55/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/735/55/table1?GETtext/xml+votable180.050000true79.657917-69.4063890.0055555555555555566/33075 33094 33096 33097 33098 33112 33113 33123 331373.322582951404819e-19 3.852589004194616e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/735/55?format=asciiOpticaldefaultJ/ApJ/735/55/table1LMC cluster sample (9 GCs)B-VB-V color indexmagphot.color;em.opt.B;em.opt.VfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCageAge classification (>5Gyr: old, 1-3Gyr: intermediate or <1Gyr: young)time.agecharNGCGlobular cluster NGC numbermeta.id;meta.mainintprimaryRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainVmagV-band magnitude (1)magphot.mag;em.opt.Vfloate_B-V? B-V uncertaintymagstat.error;phot.color;em.opt.BfloatnullableE(B-V)? B-V color excessmagphot.color.excessfloatnullablee_E(B-V)? E(B-V) uncertaintymagstat.errorfloatnullablel_AgeLimit flag on Agemeta.code.error;time.agecharAgeAgeGyrtime.agefloat[Fe/H]Fe/H abundancephys.abund.Fefloat[a/fe]? {alpha}/Fe abundance (2)phys.abundfloatnullableRefReference(s) (3)meta.ref;pos.framecharSimbadSimbad column added by the CDSmeta.refcharNEDSimbad column added by the CDSmeta.refcharJ/ApJ/735/55/ewLine parameters and integrated light equivalent widths for 9 LMC GCsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNGCLMC GC numbermeta.id;meta.mainintIon[Fe I] Species identification (FeI only)phys.atmol.ionStagecharlambdaWavelength in Angstroms0.1nmem.wldoubleExPotExcitation potentialeVphys.atmol.excitationfloatlog(gf)Log of the oscillator strengthphys.atmol.oscStrengthfloatEW? Equivalent width in units of milli-Angstroms1e-13mspect.line.eqWidth;arith.ratiofloatnullable