The cyanogen distribution of the red giants in M 5.
Abstract
On the basis of a spectroscopic survey of 29 red giants from the globular cluster M5 it was observed that cyanogen distribution is strongly bimodal in the (-1.7) to (-0.5) magnitude range. The ratio of CN-strong to CN-weak stars is 2.6 to 1, and the CN-weak stars are observed to have stronger G bands than CN-strong stars. M5 is thus one of four or five other clusters from a sample of 12 to appear bimodal with respect to cyanogen. Attention is likewise given to the possibility that there is a connection between the distribution of stars on the horizontal branch of M5 and its cyanogen distribution of the red giants as has been suggested by NGC 6752 and M4. Future work will examine the horizontal branch distribution based on high-quality photoelectric standards.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 1983
- DOI:
- 10.1086/160588
- Bibcode:
- 1983ApJ...264..215S
- Keywords:
-
- Abundance;
- Astronomical Spectroscopy;
- Cyanogen;
- Late Stars;
- Red Giant Stars;
- Stellar Evolution;
- Horizontal Branch Stars;
- Spectral Line Width;
- Astrophysics