In this section, we describe what the Scenario Machine is and how it
works. Monte-Carlo simulations of binary star evolution allows one to
study the evolution of a large ensemble of binaries and to estimate
numbers of binaries at different evolutionary stages simultaneously .
Originally, this method for statistical study of binary evolution
was proposed by Kornilov and Lipunov
(1983a,b)[85, 86] to investigate the
spin evolution
of magnetized NS in massive binary systems. Lipunov and
Postnov
(1987a,b,c, 1988)[114, 112, 113, 116]
simulated low-mass binary evolution focusing on spin evolution of
magnetized WD. Dewey and Cordes (1987)[45] and
Bailes (1989)[7] applied a similar method for analysis of
radio pulsar statistics; de Kool (1992)[42] and de Kool and
Ritter (1993)[43] performed a detailed investigation using
the Monte-Carlo method of the formation and diverse properties of
galactic cataclysmic variables. Using a similar approach, Tutukov and
Yungelson (1993b)[197] studied the formation of NS in
binary systems (see also Yungelson *et al.*, 1994[216]). A more
detailed Monte-Carlo simulation of binary stellar evolution in young
open clusters until both stars have become compact objects was recently
reported by Pols and Marinus (1994)[163].

Of course, inevitable simplifications of analytical description of the binary evolution used to avoid extensive numerical calculations, mean that the numbers of different types of binaries are uncertain to within a factor of 2-3; ratios between various binary stellar populations are more precise.

Another method which is widely used for binary evolution studies is the calculation of distribution functions (see, e.g. Iben and Tutukov, 1984a,b;[72, 73] Meurs and van den Heuvel, 1989;[141] van den Heuvel, 1994,[205] for general discussion). However, within the framework of this method it is very difficult to take into account numerous factors influencing stellar evolution; it is especially hard to include even at a qualitative level the spin evolution of magnetized compact stars.

- Notes on Monte-Carlo Simulations
- Dependence on the Scenario Parameters and Initial Distributions
- How to Catch ``Rare'' Tracks
- Principles of Scenario Machine Operation
- Calculation of Evolutionary Tracks

Sat Feb 22 18:38:13 MSK 1997