Barium stars abundances and kinematics

DOI

In this paper, we present an homogeneous analysis of photospheric abundances based on high-resolution spectroscopy of a sample of 182 barium stars and candidates. We determined atmospheric parameters, spectroscopic distances, stellar masses, ages, luminosities and scaleheight, radial velocities, abundances of the Na, Al, {alpha}-elements, iron-peak elements, and s-process elements Y, Zr, La, Ce, and Nd. We employed the local thermodynamic equilibrium model atmospheres of Kurucz and the spectral analysis code MOOG. We found that the metallicities, the temperatures and the surface gravities for barium stars cannot be represented by a single Gaussian distribution. The abundances of {alpha}-elements and iron peak elements are similar to those of field giants with the same metallicity. Sodium presents some degree of enrichment in more evolved stars that could be attributed to the NeNa cycle. As expected, the barium stars show overabundance of the elements created by the s-process. By measuring the mean heavy-element abundance pattern as given by the ratio [s/Fe], we found that the barium stars present several degrees of enrichment. We also obtained the [hs/ls] ratio by measuring the photospheric abundances of the Ba-peak and the Zr-peak elements. Our results indicated that the [s/Fe] and the [hs/ls] ratios are strongly anticorrelated with the metallicity. Our kinematical analysis showed that 90 per cent of the barium stars belong to the thin disc population. Based on their luminosities, none of the barium stars are luminous enough to be an asymptotic giant branch star, nor to become self-enriched in the s-process elements. Finally, we determined that the barium stars also follow an age-metallicity relation.

Cone search capability for table J/MNRAS/459/4299/sample (Basic informations (table1), atmospheric parameters (table3), abundances ratio (table7 and 8) and mass, distance, luminosity (table12) of the stuided stars)

Identifier
DOI http://doi.org/10.26093/cds/vizier.74594299
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/MNRAS/459/4299
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/459/4299
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/459/4299
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/MNRAS/459/4299
Provenance
Creator de Castro D.B; Pereira C.B; Roig F; Jilinski E; Drake N.A; Chavero C.,Sales Silva J.V
Publisher CDS
Publication Year 2016
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Interdisciplinary Astronomy; Natural Sciences; Physics; Stellar Astronomy