Search results for "Barium star"
showing 2 items of 2 documents
On metal-deficient barium stars and their link with yellow symbiotic stars
2005
This paper addresses the question of why metal-deficient barium stars are not yellow symbiotic stars (YSyS). Samples of (suspected) metal-deficient barium (mdBa) stars and YSyS have been collected from the literature, and their properties reviewed. It appears in particular that the barium nature of the suspected mdBa stars needs to be ascertained by detailed abundance analyses. Abundances are therefore derived for two of them, HD 139409 and HD 148897, which reveal that HD 148897 should not be considered a barium star. HD 139409 is a mild barium star, with overabundances observed only for elements belonging to the first s-process peak (Y and Zr). The evidence for binarity among mdBa stars is…
An abundance analysis of the single-lined spectroscopic binaries with barium stars-like orbital elements
1997
Detailed abundance analyses have been car- ried out for 17 single-lined binaries (giants and dwarfs) with orbital elements and mass functions similar to those of barium stars, using high-dispersion CCD spectra and model atmospheres. All these binary systems contain an unseen low-mass component, presumably, a white dwarf. A mild enhancement (+0:1 0:25 dex) of the averaged s- process elements abundances has been found only for two stars. The heavy-element overabundances in these stars are much less marked than those of the classical barium stars having similar orbital periods. We have concluded that the existence of a white dwarf (WD) companion in binary systems with barium star like characte…