Brown dwarfs as close companions to white dwarfs
- Lick Observatory, Santa Cruz, CA (USA) Lunar and Planetary Institute, Houston, TX (USA)
The influence of the radiation flux emitted by a white dwarf primary on the evolution of a closely orbiting brown dwarf (BD) companion is investigated. Full stellar evolutionary calculations are presented for both isolated and thermal bath cases, including effects of large variations in the atmospheric grain opacities. High grain opacities significantly increase the radii of the BDs, but the thermal bath does not. The major influence of the thermal bath is to increase substantially the surface temperature and luminosity of the BD at a given age. These results are compared with the observational properties of the possible BD companion of the white dwarf G29-38. Inclusion of both physical effects, high grain opacities and thermal bath, increases the mass range (0.034-0.063 solar masses) of viable models significantly, yet the final determination of whether the object is indeed a BD requires improvements in the observations of the system's properties. 37 refs.
- OSTI ID:
- 6917973
- Journal Information:
- Astrophysical Journal; (USA), Vol. 349; ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
GENERAL PHYSICS
BINARY STARS
STAR EVOLUTION
WHITE DWARF STARS
RADIATION FLUX
DWARF STARS
HERTZSPRUNG-RUSSELL DIAGRAM
LUMINOSITY
MASS
MATHEMATICAL MODELS
STELLAR RADIATION
DIAGRAMS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
STARS
640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar
Radio & X-Ray Sources