The Influence of the Initial Mass Function on Populations of X-ray Binaries After a Burst of Star Formation

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In this article we use "Scenario Machine" - the population synthesis simulator- to calculate the evolution of the populations of the selected types of X-ray sources after the starformation burst with the total mass in binaries 1.5·10⁶ M during the first 20 Myr after the burst. Sources of the four types were calculated: transient sources- accreting neutron stars with Be- stars; accreting neutron stars in pair with supergiants; Cyg X-1-like sources- black holes with supergiants; superaccreting black holes. We used two values of the α- coefficient in the mass-function: 2.35 (Salpeter's function) and 1.01 ("flat spectrum"). The calculations were made for two values of the upper limit of the mass-function: 120 and 30 M. For the flat spectrum the number of sources of all types significantly increased. Decreasing of the upper mass limit below the critical mass of a black hole formation increase (for the "flat spectrum") the number of transient sources with neutron stars up to ≈ 300. We give approximating formulae for the time dependence of source numbers.