With the VLA telescope (Very Large Array,Astronomers from the National Radio Astronomy Observatory were able to first see and get clear images of the torus of one of the two supermassive black holes in the center of the radio galaxy Cygnus A. This observation confirms the theory of the “single” origin of all types of quasars.
According to modern concepts in the centerEach galaxy in the universe is a supermassive black hole, absorbed matter (gas and dust) from the accretion disk around it. From time to time, a part of this matter is ejected by a black hole in the form of a jet — a thin beam of gas accelerated almost to light speed, and has a tremendous amount of energy in the form of optical and X-ray radiation.
Theories and computer modeling talk aboutthat the black hole itself and its accretion disk are enclosed in another very dense “layer” of matter in the form of a “donut” or toroid also of gas and dust, which prevents the propagation of jet radiation, and also holds gas and dust inside the accretion disk . Due to its presence, even galaxies similar to each other will look completely different for us if you look at them "from the side" or "from above." Thus, it was suggested that all active galaxies, whose centers contain quasars or blazars, are seen from the side of the hole in this donut, and black hole emissions in quieter clusters of stars are hidden from our eyes by a cocoon of dust and gas.
Some astronomers with such an explanation do notagree, considering that the difference in the appearance of galaxies is associated with the peculiarities of the structure of their nuclei, which are still unknown to science. Chris Carilli and his team of astrophysicists from the National Radio Astronomy Observatory, in turn, were able to prove that skeptics are mistaken in this matter. To this conclusion, scientists led the observation of the central part of the galaxy Cygnus A, the study of which was carried out using the VLA radio telescope.
A couple of years ago, the same group of scientists literallysense, accidentally discovered in this galaxy the presence of another supermassive black hole. The discovery was made during the calibration of the equipment of the telescope, which by that time had passed the next modernization. The researchers decided to study in detail both objects in the center of Cygnus A and try to identify traces of their possible interaction.
Due to the increased sensitivity andthe resolution of the new equipment VLT, astronomers were able to get the first clear images of the accumulation of gas and dust in the form of a toroid around one of the black holes and its accretion disk. Observation of these objects was carried out at different frequencies. Then, the resulting images were combined, filtering information related to the radiation of the black hole itself and its accretion disk. Thanks to such manipulations, scientists were able to see a disc-shaped structure located at a distance from the alleged center of the black hole. The researchers explain that the radius of this structure is about 860 light years, and the thickness is about 900 light years.
Scientists are not sure what kind of structure it hasthis torus, however, the calculation of the ratio of its brightness and estimated density indicate that it may be inhomogeneous. According to the researchers, the “bagel” consists of small clusters of clouds of gas and dust, with different degrees of ionization and density.
The proposed scheme of the structure of the "donut" of black holes
Carilli and his team believe that theirThe study fully supports the theory of the general origin of all types of quasars. In the future, with the help of other telescopes, scientists plan to find out the chemical composition and structure of the torus of this black hole.
“We are glad that we were finally able to see oureyes object, in whose existence we have long been convinced. In order to understand its exact composition and form, we will need to conduct new observations. For example, using the ALMA telescope, we can map the distribution of dust and gas inside it, ”adds Carilli.
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