CNO and Li abundances and 12C/13C isotopic ratios have been derived for two metal-poor Ba giants, HD 104340 and HD 206983, and two CH subgiants, HD 50264 and HD 87080. High resolution spectra obtained with the 1.52 m telescope and the FEROS echelle spectrograph at ESO, La Silla, Chile, were used in this study. CNO and Li abundances so as 12C/ 13C isotopic ratios were determined by applying the synthetic spectrum method to the lines of C2, CH, CN, [O I and Li I. Our analysis showed that the giant stars studied here have quite different natures: HD 206983 is a metal-poor barium star while HD 104340, although showing enhancement of s-process elements, should not be considered as a classical barium star: its barium syndrome can be explained by internal nucleosynthesis. The low metallicity giant HD 104340 can experience deeper convective mixing and, consequently, a larger dredge-up of CNO-cycle products compared to normal red giants. Light element abundance pattern of HD 104340 resembles anomalies resulting from the appearance on the stellar surface of material enriched in triple- and CNO cycling.

Original languageEnglish
Pages (from-to)304-306
Number of pages3
JournalProceedings of the International Astronomical Union
Volume2
Issue numberS239
DOIs
StatePublished - 1 Aug 2006

    Scopus subject areas

  • Medicine (miscellaneous)
  • Astronomy and Astrophysics
  • Nutrition and Dietetics
  • Public Health, Environmental and Occupational Health
  • Space and Planetary Science

    Research areas

  • Stars: abundances, Stars: chemically peculiar, Stars: evolution, Stars: individual (HD 50264, HD 87080, HD 104340, HD 206983)

ID: 49048729