J/ApJS/111/377ivo://CDS.VizieR/J/ApJS/111/377doi:10.26093/cds/vizier.21110377CDSWorthey G.Ottaviani D.L.1998-03-15T14:50:04Z1998-03-15T15:49:58ZCDS support team

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

cds-question@unistra.frstellar-populationsline-intensitiesnarrow-band-photometryatomic-spectroscopyThe H{gamma} and H{delta} absorption features are measured in a sample of 455 (out of an original 460) Lick IDS stars with pseudo-equivalent width indices. For each Balmer feature, two definitions, involving a narrow (~20{AA}) and a wide (~40{AA}) central bandpass, were measured. These four new Balmer indices augment 21 indices previously determined by Worthey et al., and polynomial fitting functions that give index strengths as a function of stellar temperature, gravity, and [Fe/H] are provided. The new indices are folded into models for the integrated light of stellar populations, and predictions are given for single-burst stellar populations of a variety of ages and metallicities. Contrary to our initial hopes, the indices cannot break a degeneracy between burst age and burst strength in poststarbust objects, but they are successful mean-age indicators when used with sensitive metallicity indicators. An appendix gives data, advice, and examples of how to transform new spectra to the 25-index Lick IDS system.1997ApJS..111..377Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/111/377CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/111/377https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/111/377http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/111/377https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/111/377https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/111/377http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/111/377GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/ApJS/111/377/table2Index measurementsHD? Henry Draper (Cat. <III/135>) numbermeta.idintnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintm_HDMultiplicity index on HDmeta.code.multipcharOther1First alternate star namemeta.idcharOther2Second alternate namemeta.idcharHdeltaA*? Index equivalent width0.1nmspect.line.eqWidthfloatnullableHgammaA*? Index equivalent width0.1nmspect.line.eqWidthfloatnullableHdeltaF*? Index Equivalent width0.1nmspect.line.eqWidthfloatnullableHgammaF*? Index equivalent width0.1nmspect.line.eqWidthfloatnullableNdANumber of H{delta}A measurementsmeta.numberintNgANumber of H{gamma}A measurementsmeta.numberintNdFNumber of H{delta}F measurementsmeta.numberintNgFNumber of H{gamma}F measurementsmeta.numberintQual*Qualitymeta.code.qualint