The mass of the galactic halo derived from the luminosity function of high-velocity stars.
Abstract
The local luminosity function of high-velocity stars is derived on the basis of a complete sample of stars of large proper motion with trigonometric parallaxes. The fraction of these stars belonging to a roughly spherical galactic halo is deduced by using a kinematical criterion based on space velocities of metal-poor RR Lyrae variables. The local mass density of halo stars is about 1.7 x 10- solar masses per cubic parsec, corresponding to a fractional mass within the Sun's distance from the center of 6 percent, i.e., an order of magnitude lower than that of the massive halo proposed by Ostriker and Peebles. Subject headings: galactic structure - high-velocity stars - luminosity function - proper-motion stars - stellar statistics
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 1975
- DOI:
- 10.1086/153949
- Bibcode:
- 1975ApJ...202...22S
- Keywords:
-
- Galactic Structure;
- Stellar Luminosity;
- Stellar Mass;
- Velocity Distribution;
- Astronomical Models;
- Galactic Radiation;
- Mass Distribution;
- Star Distribution;
- Stellar Evolution;
- Stellar Motions;
- Astrophysics