Evolution of close binaries after the burst of starformation for different IMFs

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We use "Scenario Machine" -- the population synthesis simulator -- to calculate the evolution of populations of selected types of X-ray sources after a starformation burst with the total mass in binaries (1--1.5) · 10⁶ M during the first 20 Myr after a burst. We present here the results of two sets of runs of the program. In the first set we examined the following types of close binaries: transient sources-- neutron stars with Be- stars; ``X-ray pulsars''-- neutron stars in pairs with supergiants; Cyg X-1-like sources-- black holes with supergiants; ``SS443-like sources''-- superaccreting black holes. We used two values of the exponent α in the initial mass function: 2.35 (Salpeter's function) and 1 (``flat spectrum''). The calculations were made for the folowing values of the upper limit of the mass function: 120 and 30 M. For the ``flat spectrum'', suggested in (Contini et al, 1995), the number of sources of all types significantly increased. With the ``flat spectrum'' and with the upper mass limit 120 M we obtained hundreds of sources of all calculated types. Decreasing of the upper mass limit below the critical mass of a black hole formation increase the number of transient sources with neutron stars up to ≈ 300. In the second set we examined the evolution of of 12 other types of X-ray sources for α=1, α=1.35 and α=2.35 and for three upper mass limits: 120 M, 60 M, 40 M (see Perez-Olia & Colina 1995 for the reasons for such upper limits) on the same time scale 20 Myr after a star formation burst.