On the giant, asymptotic and horizontal branches of globular clusters. I. Photographic photometry of M5.
Abstract
B, V photographic photometry was obtained for stars in the globular cluster M5, and all stars with B equal to or less than 1.5 and r between 2 and 5.6 arcmin were measured. A reduction procedure was then used that is based on a multicomponent, bidimensional Gaussian fit to the data derived by scanning the plates with a PDS microphotometer. A color-magnitude diagram was then obtained having a photometric accuracy of about 0.04 mag down to a B value of 17.5. It is deduced from this data that: (1) no blue HB stars fainter than a V value of 16.4 is present; (2) the RGB and AGB are clearly separated; and (3) the ratios of the numbers of HB, RGB and AGB stars are in good agreement with the proposed evolutionary model that takes into account semiconvection and mass loss.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- August 1981
- DOI:
- 10.1093/mnras/196.3.435
- Bibcode:
- 1981MNRAS.196..435B
- Keywords:
-
- Astronomical Photography;
- Giant Stars;
- Globular Clusters;
- Horizontal Branch Stars;
- Stellar Evolution;
- Stellar Spectrophotometry;
- Asymptotic Giant Branch Stars;
- Blue Stars;
- Color;
- Color-Magnitude Diagram;
- Red Giant Stars;
- Star Distribution;
- Stellar Luminosity;
- Stellar Magnitude;
- Stellar Mass Ejection;
- Variable Stars;
- Astrophysics