J/A+A/645/A10ivo://CDS.VizieR/J/A+A/645/A10doi:10.26093/cds/vizier.36450010CDSGil-Pons P.Doherty C.L.Gutierrez J.Campbell S.W.Siess L.,Lattanzio J.C.2021-09-09T12:16:04Z2020-12-23T10:04:08ZCDS support team

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

cds-question@unistra.frstellar-evolutionary-modelscarbon-starschemically-peculiar-starspopulation-ii-starschemical-abundancesObserved abundances of extremely metal-poor (EMP) stars in the Halo hold clues for the understanding of the ancient universe. Interpreting these clues requires theoretical stellar models at the low-Z regime. We provide the nucleosynthetic yields of intermediate-mass Z=10^-5^ stars between 3 and 7.5M_{sun}_, and quantify the effects of the uncertain wind rates. We expect these yields can be eventually used to assess the contribution to the chemical inventory of the early universe, and to help interpret abundances of selected C-enhanced EMP stars. By comparing our models and other existing in the literature, we explore evolutionary and nucleosynthetic trends with wind prescriptions and with initial metallicity. We compare our results to observations of CEMP-s stars belonging to the Halo. The yields of intermediate-mass EMP stars reflect the effects of very deep second dredge-up (for the most massive models), superimposed with the combined signatures of hot-bottom burning and third dredge-up. We confirm the reported trend that models with initial metallicity Zini<=0.001 give positive yields of ^12^C, ^15^N, ^16^O, and ^26^Mg. The ^20^Ne, ^21^Ne, and ^24^Mg yields, which were reported to be negative at Zini=0.0001, become positive for Z=10^-5^. The results using two different prescriptions for mass-loss rates differ widely in terms of the duration of the thermally-pulsing (Super) AGB phase, overall efficiency of the third dredge-up episode, and nucleosynthetic yields. The most efficient of the standard wind rates frequently used in the literature seems to favour agreement between our yield results and observational data. Regardless of the wind prescription, all our models become N-enhanced EMP stars.2021A&A...645A..10Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/645/A10CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/490/769 : Yields from extremely metal-poor stars (Campbell+, 2008)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/645/A10https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/645/A10http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/645/A10https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/645/A10https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/645/A10http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/645/A10GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/645/A10/z1em5blYields computed with wind prescription by Bloecker (1995A&A...297..727B)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintZMetallicityphys.abund.ZfloatMiniInitial masssolMassphys.massfloatWindWind prescriptionmeta.bibchareta? Wind prescription parameter (only for z1em5bl.dat file)stat.fit.paramfloatnullableSpeciesSpecies imeta.notecharA(i)Atomic mass of iphys.atmol.weightintYield(i)Yield of isolMassphys.composition.yielddoubleMeject(i)Ejected mass of isolMassphys.composition.yielddoubleMini(i)Initial mass of i, M0(i) (Msun)solMassphys.composition.yielddouble<X(i)>Average abundance of i in the windphys.abunddoubleX0(i)Initial abundance of iphys.abunddoublelog(<X(i)>/X0(i))log10 of production factor of iphys.abunddoubleJ/A+A/645/A10/z1em5vwYields computed with wind prescription by Vassiliadis and Wood (1993ApJ...413..641V)A(i)Atomic mass of iphys.atmol.weightintSpeciesSpecies imeta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintZMetallicityphys.abund.ZfloatMiniInitial masssolMassphys.massfloatWindWind prescriptionmeta.bibchareta? Wind prescription parameter (only for z1em5bl.dat file)stat.fit.paramfloatnullableYield(i)Yield of isolMassphys.composition.yielddoubleMeject(i)Ejected mass of isolMassphys.composition.yielddoubleMini(i)Initial mass of i, M0(i) (Msun)solMassphys.composition.yielddouble<X(i)>Average abundance of i in the windphys.abunddoubleX0(i)Initial abundance of iphys.abunddoublelog(<X(i)>/X0(i))log10 of production factor of iphys.abunddouble