All known black holes fall into two categories: small black holes of stellar masses, masses which are of order of several solar masses, and supermassive black holes, the mass of which number in the millions and billions of solar masses. Astronomers expect that black holes of intermediate masses, the mass of which should be from 100 to 10000 solar masses also exist, however, until now convincing evidence of the existence of such objects has been presented. In the new study, astronomers report the discovery of a black hole an intermediate-mass (intermediate-mass black hole, IMBH), the mass of which is about 2200 solar masses in a globular cluster of stars is 47 Tucanae.
“We want to detect black holes of intermediate masses, as they represent the missing link between black holes stellar-mass and supermassive black holes. They may be primary germ that grew up in those giant “monsters” that we see in the centers of galaxies,” said lead author of the study Kiziltan Bulent (Bulent Kiziltan) of the Harvard-Smithsonian astrophysical center, USA.
47 Tucanae is a star cluster about 12 billion years old, located at a distance of approximately 13000 light years away in the southern constellation of Toucan. It contains thousands of stars placed inside the sphere with a diameter of about 120 light years. It also contains about a dozen pulsars that have become an important part of this study.
In their work Kiziltan and his team identified the presence of the IMBH in the center of the cluster 47 Tucanae in two different ways: distortion of trajectories, the most severe of the stars sinking towards the center of the cluster of stars, gravity, black holes, and also a similar distortion of the trajectories of pulsars, which in the presence of a black hole can be located further from the center of the cluster than would be the case when the black hole is missing.