Team of scientists found that black holes in the center of galaxies are transformed into super-bright X-ray sources not as a result of collisions with other galaxies, as previously thought, but by internal processes in stellar systems.In the center of many of the large spiral galaxy are hidden supermassive black holes. Their weight in the millions and even billions of times greater then the mass of the Sun. In most galaxies, including our own, these black holes behave calmly.In some galaxies the central black holes behave in a very “aggressive” , they throw out the powerful jets of matter to the surrounding and strongly emit X-rays.
Such objects astronomers called active galactic nuclei.Astronomers believe that black holes are “included” as a result of collision or a close approximation of the galaxies. But now an international group of scientists, part of the collaboration of COSMOS, has determined that such cosmic accident trigger only a small fraction of active nuclei. The study’s authors examined data from the European orbital X-ray telescope XMM-Newton in the survey portion of the sky (the area around the full moon) in the constellation of a Sextant, where was discovered about 600 active galactic nuclei. Astronomers have discovered that most of the active nuclei located in galaxies with a large mass and a large number of dark matter. This was contrary to the prediction of the theory of collisions: if the supermassive black holes become active after the “accident”, they would be more common in galaxies with moderate mass, about a trillion solar masses.However, in galaxies the most active nuclei were about 20 times heavier than predicted by the theory of mergers.This indicates that black holes feed by processes of inside galaxies themselves, such as the instability disks or starbursts and not by collisions.