ИСТИНА

Recently discovered bursts of gravitational waves provides a good opportunity to verify the current view on the evolution of close binary stars. Modern population synthesis codes help to study this evolution from two main sequence stars up to the formation of two final remnant degenerate dwarfs, neutron stars or black holes. To study the evolution of predecessors of BH mergers we use the "Scenario Machine" code. The scenario modeling allowed to describe the evolution of systems for which the final stage is a massive BH+BH merger. Our calculations show the plausibility of modern evolutionary scenarios for binary stars and the population synthesis modeling based on it. We discuss a possible values of spins of BH mergers, and give arguments in favour of different values of BH spins in BH mergers (low spin + low spin, high spin + high spin, low spin + high spin, etc).