Chemical composition of five giants with positive CN-indices.
Abstract
We derived the atmospheric parameters and chemical composition of five stars with positive CN-index from high dispersion coude echelle spectra obtained using the 1-m telescope of the Special Observatory of the Russian Academy of Sciences, equipped with a CCD detector. We found that HD 176411, HD 181984, HD 190940, and HD 207130 are normal giants in the post first dredge-up phase; HD 222404 (γ Cep) is possibly an unmixed star. HD 181984 (τ Dra), a suspected super-metal-rich star, has a metallicity of [Fe/H]=+0.10dex. It shows underabundances of C and O, and overabundances of Na, Al, Mn. HD 176411, HD 190940, and HD 207130 show nearly solar metallicity, underabundances of C and O, and overabundances of Na and Al. The derived abundances of O, Na (and Al) might be an evidence for anomalous mixing in these stars. HD 222404 has a nearly solar chemical composition. The program stars have on average solar abundances for Y, Zr, Ba, La, Ce, Pr, and Nd, within the errors of determination.
- Publication:
-
Astronomy and Astrophysics Supplement Series
- Pub Date:
- October 1995
- Bibcode:
- 1995A&AS..113..333M
- Keywords:
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- STARS: ABUNDANCES;
- STARS: ATMOSPHERES;
- STARS: EVOLUTION;
- STARS: GIANTS