J/A+A/334/987ivo://CDS.VizieR/J/A+A/334/987doi:10.26093/cds/vizier.33340987CDSVenn K.A.Smartt S.J.Lennon D.J.Dufton P.L.1998-07-05T15:55:24Z1998-07-05T15:55:15ZCDS support team

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

cds-question@unistra.frearly-type-starsspectroscopyAs part of a programme to investigate spatial variations in the Galactic chemical composition, we have been searching for normal B-type stars and A-type supergiants near the Galactic center. During this search we have found eleven peculiar stars, and in some cases performed detailed abundance analyses of them which suggest that they may be at a post-AGB evolutionary stage. The A-type post-AGB candidates show [Fe/H]=-1.0 to -2.0, and [O/Fe]~+1.4, typical of the post-AGB abundance patterns discussed in the literature. One star, LS 3591 (=SAO 243756), has also been examined recently by Oudmaijer (1996A&A...306..823O); its spectrum appears to be changing very rapidly, which may indicate erratic mass loss or the incipient formation of a planetary nebula. A B-type post-AGB candidate, LS 4950, has a similar spectrum to a well studied post-AGB star, LSIV -12 111. However, an examination of the line strengths and elemental abundances of LS 4950 show that it is peculiar for both a PopulationII, post-AGB, B-type star and for a normal, PopulationI, B-type supergiant. Two other B-type stars, LS 4825 and LS 5112, are either post-AGB stars near the Galactic center or normal B-type supergiants lying well beyond the Galactic center. In addition, several Be-type stars have been newly (or more clearly) identified from our spectra.1998A&A...334..987Vhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/334/987CatalogResearchIsServedByTAP VizieR generic servicerelated-toVI/72 : Atomic Transition Probabilities, Sc-Ni (NIST 1993)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/334/987https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/334/987http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/334/987https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/334/987https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/334/987http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/334/987GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/A+A/334/987/appena*Spectral line data for two post-AGB A-type starslambdaWavelength0.1nmem.wlfloatIonIonphys.atmol.ionizationcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRMTMultiplet numberphys.atmol.levelintchiExcitation potentialeVphys.energy;phys.atmol.excitationfloatloggflog of oscillator strengthphys.atmol.wOscStrengthfloatEWLS3591? Equivalent width for the star LS 3591nmspect.line.eqWidthfloatnullableu_EWLS3591Uncertainty flag on EWLS3591meta.code.errorcharEWLS3593? Equivalent width for the star LS 3593nmspect.line.eqWidthfloatnullabler_loggfReference for the oscillator strength (1)meta.refcharJ/A+A/334/987/appenb*Spectral line data for four B-type stars towards the Galactic CenterIonIon (1)phys.atmol.ionizationcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlambdaWavelength0.1nmem.wlfloatlambda2? Second wavelength (2)0.1nmem.wlfloatnullableEWLS4950? Equivalent width for the star LS 4950nmspect.line.eqWidthfloatnullableEWLS4039? Equivalent width for the star LS 4039nmspect.line.eqWidthfloatnullableEWLS4825? Equivalent width for the star LS 4825nmspect.line.eqWidthfloatnullableEWLS5112? Equivalent width for the star LS 5112nmspect.line.eqWidthfloatnullable