A Fine Abundance Analysis of Four Stars in the gamma Per Cluster- a Cautionary Tale
Abstract
High-resolution spectra of the F5 I β supergiant α Per and three dwarfs belonging to the α Per cluster were obtained in order to search for systematic differences in the abundances. Using LTE analyses of the spectroscopic data we have found that [Fe/H] is about 0.3-0.5 dex smaller for α Per as compared to the dwarfs, which we ascribe primarily to non-LTE effects in the analysis of α Per. If this result is confirmed, then it will be necessary to correct LTE abundance analyses that have been performed on supergiants. Surprisingly, our estimate for the mean value of [Fe/H] for the dwarfs is 0.17±0.06 dex; this value is significantly larger than the accepted value for the cluster, about [Fe/H]=0.04. While we have not been able to determine the source of this discrepancy, there is some evidence that it is due to chromospheric activity.
- Publication:
-
The Astronomical Journal
- Pub Date:
- January 1996
- DOI:
- 10.1086/117795
- Bibcode:
- 1996AJ....111..424G
- Keywords:
-
- OPEN CLUSTERS AND ASSOCIATIONS: INDIVIDUAL: GAMMA PER;
- SUPERGIANTS