1996A&A...309..179P

We present a model for the evolution of a population of single stars and binaries, in which the eccentricity of initial binaries and mass transfer between the binary components are taken into account. To illustrate the model, we apply it to the formation of neutron stars, both single and in binaries. The eccentricity of primordial binaries allows a wide, non-interacting binary to survive the first and second supernovae in many more cases than suggested by previous calculations that assume circular orbits. Mass transfer in binaries enhances the rate of type I supernovae with respect to that of the type II supernovae. A sizable fraction of initial binaries merge into a single star; 10-15% of the type II supernovae are from such mergers. Models in which neutron stars receive a kick velocity at birth predict birth rates for wide and close radio-pulsar binaries, and for high-mass (including Be-) X-ray binaries that are roughly in agreement with observations. All our models produce too many Her X-1 type binaries. The formation rate of radio-pulsars that remain in a binary after the first supernova explosion and are released at the second supernova event is predicted by our models to be comparable to the formation rate of recycled binary radio pulsars, i.e. less than a few per cent of the formation rate of single radio pulsars.