The population of close double white dwarfs in the Galaxy

Abstract

We present a new model for the Galactic population of close double white dwarfs. The model accounts for the suggestion of the avoidance of a substantial spiral-in during mass transfer between a giant and a main-sequence star of comparable mass and for detailed cooling models. It agrees well with the observations of the local sample of white dwarfs if the initial binary fraction is close to 50% and an ad hoc assumption is made that white dwarfs with mass less than about 0.3 solar mass cool faster than the models suggest. About 1000 white dwarfs brighter than V=15 have to be surveyed for detection of a pair which has total mass greater than the Chandrasekhar mass and will merge within 10 Gyr.

15 pages, 7 figures, to appear in Proc. ``The influence of binaries on stellar population studies'', Brussels, August 2000 (Kluwer, D. Vanbeveren ed.)

References in corpus (6)

• KPD1930+2752 - a candidate Type Ia supernova progenitor
• A Survey for Cool White Dwarfs and the age of the Galactic Disc
• Cooling curves and initial models for low-mass white dwarfs (<0.25 Msun) with helium core
• The triple degenerate star WD1704+481
• Detached white-dwarf close-binary stars -- CV's extended family
• Confirmation of Eclipses in KPD 0422+5421, A Binary Containing a White Dwarf and a Subdwarf B Star

Cited by in corpus (3)

• The astrophysical gravitational wave stochastic background
• Parameter estimation for Galactic binaries by LISA
• The Discovery of a Companion to the Lowest Mass White Dwarf