Degenerate dwarfs in binary systems.

A model of the ensemble of the white dwarf population of the Galaxy formed in binary systems is obtained. It is shown that up to 24 percent of initial binary stars end their evolution as single objects. It is further found that up to 80 percent of all white dwarfs more massive than 0.65 solar mass must be single merger products. It is also shown that only about 10 percent of degenerate dwarfs have semiamplitudes of radial velocities exceeding 100 km/s and less than 1 percent have orbital periods shorter than 3 hours.