L151-81A/B: A Unique White Dwarf Binary with DB and DA Components
Abstract
Spectroscopic observations of the wide binary L151-81A/B reveal that both components are white dwarfs with spectral types DB3 and DA4, the first such binary identified in a comprehensive survey of Luyten and Giclas common proper motion pairs. Assuming log g = 8, measurements of the helium line profiles in the DB primary yield Teff = 16,000 + or - 2,000, while the hydrogen profiles for the DA companion yield Teff =12,000 + or - 2,000. The existence of a helium-rich/hydrogen-rich degenerate pair offers several interesting tests of theoretical white dwarf formation channels and surface abundance evolution.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- October 1988
- DOI:
- 10.1086/185293
- Bibcode:
- 1988ApJ...333L..87O
- Keywords:
-
- Astronomical Photography;
- Binary Stars;
- Spectroscopic Analysis;
- Stellar Motions;
- Stellar Spectra;
- White Dwarf Stars;
- Helium;
- Hydrogen;
- Signal To Noise Ratios;
- Spectral Resolution;
- Astrophysics;
- STARS: BINARIES;
- STARS: PROPER-MOTION;
- STARS: SPECTRA;
- STARS: WHITE DWARFS