Next: Binary Pulsar Diversity and Up: Restrictions on the Scenario Previous: Phenomenological Kick Velocity
Let us consider what fraction of different types of binary radiopulsars can be obtained within the framework of the modern evolutionary scenario of binary stars if a phenomenological kick velocity caused by the collapse anisotropy is added. Several attempts of this kind have been made over the last 10 years (Kornilov and Lipunov, 1984; Tutukov et al., 1984; Dewey and Cordes, 1987; Bailes, 1989). The observational data existing at that time convincingly pointed to the presence of a small kick velocity of about 70-100 km s . However, the statistics of binary radiopulsars at that time was very poor. Of course, all such studies are restricted considering the evolution of an ensemble of stars that initially originated from binaries and were not tidally captured, as occurs in globular clusters; so the numerous binary pulsars observed in globular clusters and whose evolution is not yet fully understood must be excluded from consideration.
Here, we focus on the ratio of binary to single pulsars as a function of the kick velocity; use of the binary pulsar type fraction among single pulsars allows us to get rid of many poorly known pulsar parameters (such as the characteristic time of magnetic field decay). We stress that especially for binary NS the results are fully independent the decay time.
Mass loss and kick velocity are the processes leading to binary system disruption; however, there are a number of processes connected with the orbital momentum losses tending to bound the binary (e.g. gravitational radiation, magnetic stellar wind). For massive binaries (with primary mass ), which produce the vast majority of NS in binaries, a more important and effective process is the orbital angular momentum loss during the CE stage. As already mentioned, a flat distribution by semi-major axes of the binaries makes the uncertainty in rather insignificant. Below we put .
We compare the calculated (``C'') and observed (``O'') numbers of binary radiopulsars with NS (PSR+NS), WD (PSR+WD), planets (PSR+PL), and normal OB-stars (PSR+OB). The observed numbers of the binary pulsars in the galactic disk and their assumed scenario origin are presented in Table 6.