The Origin and Evolution of Helium-Rich White Dwarfs (review)
Abstract
White dwarfs with helium-rich atmospheres constitute about one fifth of the white dwarfs hotter than 12,000K. They appear to have a mass distribution similar to the hydrogen atmosphere (DA) stars, and are similar in other properties. However, the temperature distribution exhibits a deficiency of DB/DO stars in the interval 25,000 - 45,000K, which implies evolution in the dominant surface composition as the stars cool. The hottest group of transition DO white dwarfs are the pulsating objects of the PG 1159 class. The central star of K1-16 is a related object, as may be the newly discovered very hot star H 1504+65, which shows no detected surface features of either hydrogen or helium.
- Publication:
-
IAU Colloq. 87: Hydrogen Deficient Stars and Related Objects
- Pub Date:
- 1986
- DOI:
- 10.1007/978-94-009-4744-3_31
- Bibcode:
- 1986ASSL..128..367L
- Keywords:
-
- Abundance;
- Helium;
- Stellar Evolution;
- Stellar Temperature;
- White Dwarf Stars;
- Hertzsprung-Russell Diagram;
- Hot Stars;
- Mass Distribution;
- Star Distribution;
- Stellar Oscillations;
- Temperature Distribution;
- Astrophysics