Spectroscopic Investigations of Galactic Clusters with Associated Cepheid Variables. II. NGC 5662 and V Cen
Abstract
We present the results of a spectroscopic and photometric investigation of 15 objects from the open cluster NGC 5662, which contains the Cepheid V Cen. Besides the Cepheid, we studied one G-supergiant, two K-giants, four B-giants, and seven main sequence stars. Radial velocities (RV), v sin i, Teff, log g, and [Fe/H] were determined using model fitting. We have derived the color-excesses, reddenings, and intrinsic colors for these stars to determine their true Teff and log g from comparison to the atmosphere models, especially for hot stars, and to determine their absolute magnitudes. RV and GAIA DR2 2018 parallax/distance values for these stars allowed us to determine their membership in the cluster and to construct it 3D kinematic models. These parallaxes and reddenings led to the distances in a range of 700-875 pc, while photometric MV gave the distances of 550-660 pc. Two objects from our list were found to be non-members of the cluster, and two other objects to be background stars. All members have [Fe/H] =-0.1±0.04 dex. The main sequence stars and B-giants have abundances of C, N, and Na close to the solar one, while the cool supergiants and giants show a deficit of carbon, an overabundance of nitrogen, and a small overabundance or close to the solar sodium content. Two Li-rich K-giants, HD 127733 and HD 127753, were discovered in the cluster.
- Publication:
-
Odessa Astronomical Publications
- Pub Date:
- 2018
- DOI:
- 10.18524/1810-4215.2018.31.145381
- Bibcode:
- 2018OAP....31..117U
- Keywords:
-
- Open clusters: radial velocities;
- Stars: abundance;
- GAIA parallaxes;
- Cepheids;
- Lithium giants;
- individual: NGC 5662;
- V Cen;
- HD 127733;
- HD 127753