SIMBAD references

The "Scenario Machine" (Monte Carlo simulations of binary evolution) which permits to build up a complete picture of all possible evolutionary stages of binaries in the Galaxy is used to study parameters of binary evolution scenario. Ratios of different populations of binary systems turn out to be most sensitive to the initial binary mass ratio distribution, f(q), (q=M₂/M₁<1), the efficiency of angular momentum removal during common envelope (CE) stage α_CE, and value of additional kick velocity imparted to young pulsars during supernova explosions. We find that our model gives the best agreement with the observations (within a half-order-of-magnitude difference between the observed (O) and calculated numbers (C) C/O+O/C≃3.3) if f(q)∝q^1.5, which is centered toward equal initial masses. Common envelope efficiency α_CE is found to less effect the results, allowing a range α_CE∼0.1-10. The best value of mean kick velocity w found by comparing the calculations with observational data on the galactic X-ray luminosity and binary radiopulsars statistics is ∼100-200km/s; the currently popular high mean kick velocity of 450 km/s would give C/O+O/C≃6-10 depending on the assumed kick velocity distribution.