The ground-based ALMA radio telescope has helped astronomers determine that only a tiny fraction of the gas flowing toward the supermassive black hole at the center of the active galaxy Circulus will be absorbed by it. The remaining gas in different phases forms countless streams of escaping matter, some of which then returns to the black hole. The article was published in the journal Science. Supermassive black holes are found everywhere in the centers of galaxies and may exhibit activity due to the accretion of material entering the circular disk at the center of the galaxy from the intergalactic medium. or from galaxies with which the black hole’s host galaxy merges or interacts. In this case, the feedback effect may come into play: high activity of the galactic nucleus may increase the flux of matter from the interior of the system, negatively affecting the star formation process .
A team of astronomers led by Takuma Izumi of the National Astronomical Observatory of Japan has announced the results of submillimeter observations of the Compass galaxy using the ALMA radio telescope system. Scientists want to monitor the flow of matter to and from the black hole in the galactic core at subparsec scales. Observations were made on the emission lines of hydrogen cyanide (which allows us to trace a very dense molecular gas), carbon alone, and ionized carbon monoxide (responsible for a medium-density molecular gas). cylinder and diffuse atomic gas), as well as on the recombination line of atomic hydrogen. (responsible for ionized gas flow).
The Circulus galaxy is one of the closest active galaxies to the Sun (about 13 million light years away), exhibiting moderate X-ray activity. Its core contains a supermassive black hole, heavily obscured by clouds of gas and dust. A disk of gas is observed around it; Additionally, a giant cone of ionized gas emitting from the core was detected. The researchers confirmed the presence of a cone of ionized gas up to one kiloparsec in size and also provided a new estimate of the mass of the supermassive black hole, equal to two million solar masses, consistent with previous estimate. In some analyzes from black holes, diffuse atomic gas forms a thick structure, while dense molecular gas forms a thin disk. The rate at which matter flows into the black hole is 0.2 to 0.34 solar masses per year. This is enough to explain the observed X-ray brightness at the galaxy’s core. The rate at which ionized gas escapes from the black hole is 0.04 solar masses per year.
Scientists concluded that less than 3% of the mass of gas flowing toward the black hole will be absorbed by it. The rest of the matter will enter the multiphase flow from the black hole, with about 20% of the mass being ionized gas. Due to their relatively low speeds, these flows would then be slowed by the black hole’s gravity and their material would return to the nuclear disk.