Stellar populations in the Galaxy
Abstract
The stellar populations in the Galaxy are discussed, including those of the halo and the disk, and the requirements for constructing a stellar population model of the Galaxy are examined. Challenges to the view that the age spread of the globular clusters is characterized by a free-fall time for the Galaxy are discussed, as are the evidence that the clusters and the field halo form separate subsystems. The nature of the M stars in the nuclear bulge and the special characteristics of the stellar population of the outer halo are focused on. The age, kinematics, and composition of both the old and the young disk population are discussed. Radial abundance gradients in the disk are examined. The qualitative features of a two-component model are presented that describes the stellar age distribution at any point in the Galaxy and the kinematics and metallicity distribution there.
- Publication:
-
Annual Review of Astronomy and Astrophysics
- Pub Date:
- 1982
- DOI:
- 10.1146/annurev.aa.20.090182.000515
- Bibcode:
- 1982ARA&A..20...91M
- Keywords:
-
- Astronomical Models;
- Galactic Structure;
- Milky Way Galaxy;
- Star Distribution;
- Abundance;
- Galactic Bulge;
- Galactic Nuclei;
- Globular Clusters;
- Halos;
- M Stars;
- Rotating Disks;
- Stellar Evolution;
- Stellar Models;
- Stellar Motions;
- Astrophysics