J/ApJ/658/1203ivo://CDS.VizieR/J/ApJ/658/1203doi:10.26093/cds/vizier.16581203CDSJohnson J.A.Herwig F.Beers T.C.Christlieb N.2017-11-29T11:49:08Z2009-03-31T13:59:52ZCDS support team

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

cds-question@unistra.frcarbon-starschemical-abundancesTheoretical models of very metal-poor intermediate-mass asymptotic giant branch (AGB) stars predict a large overabundance of primary nitrogen. The very metal-poor, carbon-enhanced, s-process-rich stars, which are thought to be the polluted companions of now extinct AGB stars, provide direct tests of the predictions of these models. Recent studies of the carbon and nitrogen abundances in metal-poor stars have focused on the most carbon-rich stars, leading to a potential selection bias against stars that have been polluted by AGB stars that produced large amounts of nitrogen and hence have small [C/N] ratios. We call these stars nitrogen-enhanced metal-poor (NEMP) stars and define them as having [N/Fe]>+0.5 and [C/N]<-0.5. In this paper we report on the [C/N] abundances of a sample of 21 carbon-enhanced stars, all but three of which have [C/Fe]<+2.0. If NEMP stars were made as easily as carbon-enhanced metal-poor (CEMP) stars, then we expected to find between two and seven NEMP stars. Instead, we found no NEMP stars in our sample.2007ApJ...658.1203Jhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/658/1203CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/658/1203https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/658/1203http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/658/1203https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/658/1203https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/658/1203http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/658/1203GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/658/1203/table2 (Photometry data)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/658/1203/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/658/1203/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/658/1203/table2?GETtext/xml+votable180.050000true299.7072392-18.20309560.005555555555555556Cone search capability for table J/ApJ/658/1203/table10 (Additional literature values)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/658/1203/table10?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/658/1203/table10?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/658/1203/table10?GETtext/xml+votable180.050000true198.480625-12.19486110.0055555555555555566/8197 8848 16654 16659 16679 16680 16790 16865 16880 17174 17221 17392 17543 17623 17642 17679 17994 18483 18507 18637 18683 18719 18737 18973 23240 25574 25733 26057 27048 31136 33260 33526 33642 33708 34037 35009 36228 42331 44016 44541 44671 44909 45404 45806 46663 46704 46724 46791 46792 47009 47344 47478 48173 48234 48392 48501 48555 48557 48722 48798 48824 48862 49078https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/658/1203?format=asciiOpticaldefaultJ/ApJ/658/1203/table2Photometry datarecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharVmagV magnitudemagphot.mag;em.opt.VfloatB-V? B-V colour indexmagphot.color;em.opt.B;em.opt.VfloatnullableU-B? U-B colour indexmagphot.color;em.opt.U;em.opt.BfloatnullableV-R? V-R colour indexmagphot.color;em.opt.V;em.opt.RfloatnullableV-I? V-I colour indexmagphot.color;em.opt.V;em.opt.IfloatnullableV-J? V-J colour indexmagphot.color;em.opt.V;em.IR.JfloatnullableV-K? V-K colour indexmagphot.color;em.opt.V;em.IR.KfloatnullableE(B-V)Galactic colour excessmagphot.color.excessfloatSimbadNameSimbad column added by the CDSmeta.idchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/ApJ/658/1203/table10Additional literature valuesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSample[123] Sample (1)src.samplecharNameStar namemeta.id;meta.maincharlogeCC abundance (H=12)phys.abundfloatlogeNN abundance (H=12)phys.abundfloat[Fe/H]Metallicitylog(Sun)phys.abund.Zfloat[C/N]Abundance, C/Nlog(Sun)phys.abundfloatRefReference for abundancesmeta.ref;pos.framechars-el[Yes/No] s-process element rich star ?meta.codecharSimbadNameSimbad column added by the CDSmeta.idchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main