The Initial Mass Function for Very Low Mass Stars in the Hyades
Abstract
Theoretical luminosity functions at various evolutionary ages for stars and substellar objects (brown dwarfs), spanning the mass range from 0.03 to 0.2 solar mass is computed. These functions constrain the distribution of very low mass objects in a star cluster of known age. Calculations with a 1988-1989 survey of faint members of the Hyades cluster by Leggett and Hawkins (1988, 1989), a cluster whose age is 6 x 10 to the 8th yr are compared. The comparison shows that the survey does not reach sufficiently low luminosities to reveal brown dwarfs. A strong constraint on the initial mass function (IMF) for very low mass stars in the Hyades is obtained and it is inferred that its IMF does not increase with decreasing mass for the mass interval investigated here. Results imply at most a moderate contribution from brown dwarfs to the cluster mass, and to the Galaxy's mass if the Hyades are representative of the Galaxy as a whole.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 1990
- DOI:
- 10.1086/185778
- Bibcode:
- 1990ApJ...358L..53H
- Keywords:
-
- Brown Dwarf Stars;
- Star Formation;
- Stellar Luminosity;
- Stellar Mass;
- Interstellar Chemistry;
- Interstellar Magnetic Fields;
- Stellar Atmospheres;
- Astrophysics;
- STARS: BROWN DWARFS;
- STARS: FORMATION