The anomalous cluster NGC 6649 and/or Cepheid V367 Scuti.
Abstract
The evidence suggesting that the double-mode Cepheid V367 Scuti is a member of the open cluster NGC 6649 is reexamined. It is shown that the location of V367 Sct on the color-magnitude diagram of NGC 6649 is actually very different from that of other Cepheids that are cluster members and that if V367 Sct is assumed to be a cluster member, the history of star formation in NGC 6649 is very different from what is found for other open clusters, which indicates that NGC 6649 or V367 Sct is somehow anomalous. Besides the anomalous nature of this system, membership of V367 Sct in NGC 6649 has not yet been established through proper-motion or radial-velocity studies; this suggests that it is perhaps premature to include this Cepheid in the calibration of the period-luminosity relation.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 1978
- DOI:
- 10.1086/156443
- Bibcode:
- 1978ApJ...224..948F
- Keywords:
-
- Cepheid Variables;
- Star Clusters;
- Stellar Evolution;
- Anomalies;
- Color-Magnitude Diagram;
- Colorimetry;
- Open Clusters;
- Stellar Magnitude;
- Stellar Models;
- Astronomy;
- C-M Diagrams:Open Clusters;
- Cepheids:Open Clusters;
- Open Clusters: Membership