Astronomers used NASA’s Chandra X-ray Observatory and NSF’s Carl G. Jansky Very Large Array (VLA) to locate H1821+643, the closest quasar hosted by a galaxy cluster, about 3.4 billion light years away. The quasar was found to be more powerful than many supermassive black holes in other galaxy clusters.
This composite image shows quasar H1821+643.Image credit: NASA / CXC / University of Nottingham / Russell other. / NSF / NRAO / VLA / SAO / N. Walk.
Quasars are a rare and extreme class of supermassive black holes that violently pull matter inward, producing intense radiation and sometimes powerful jets.
This quasar, known as H1821+643, is about 3.4 billion light-years from Earth and contains a black hole with a mass of 4 billion solar masses.
Most growing supermassive black holes pull matter in at a slower rate than quasars.
Astronomers have been studying the effects of these more common black holes by observing black holes at the centers of galaxy clusters.
Periodic explosions from such black holes prevent the massive amount of superheated gas embedded in the black hole from cooling down, increasing the number of stars forming in its host galaxy and the fuel pouring toward the black hole. limit the amount of
Little is known about how much influence quasars within galaxy clusters have on their surroundings.
“Our research shows that quasars appear to have given up much of the control imposed by slower-growing black holes. The appetite of black holes is unmatched in their influence,” Nottingham said. University astronomer Dr Helen Russell said.
To reach this conclusion, Russell and his colleagues used Chandra to study the hot gas surrounding H1821+643 and its host galaxy.
But the bright X-rays from quasars have made it difficult to study the weaker X-rays from hot gases.
“To reveal the effects of a black hole, we had to carefully remove the X-ray glare. Then we found that it actually had little effect on its surroundings,” says Harvard University. said Dr. Paul Nalsen, an astronomer at the Smithsonian Center for Astrophysics.
Using Chandra, astronomers discovered that the density of gas near the black hole at the center of a galaxy is much higher than in more distant regions, and the temperature of the gas is much cooler.
Researchers believe that when there is little or no energy input (usually from an explosion from a black hole), hot gas behaves this way to prevent it from cooling and flowing toward the center of the cluster. Expect.
“The supermassive black hole generates far less heat than other black holes at the center of galaxy clusters. This allows the hot gas to cool rapidly and form new stars, which fuel the black hole. It also acts as a source,” said Dr Lucy Crews, an astronomer at the Open University.
The researchers determined that the equivalent of about 3,000 solar masses per year of hot gas has cooled to the point where it is no longer visible in X-rays.
This rapid cooling easily supplies enough material for the 120 solar masses of new stars observed to form each year within the host galaxy and the 40 solar masses consumed by black holes each year. be able to.
The scientists also investigated the possibility that radiation from quasars directly causes cooling of the cluster's hot gases.
This involves photons of light from the quasar colliding with electrons in the hot gas, increasing the energy of the photons and causing the electrons to lose energy and cool down.
This study showed that this type of cooling is probably occurring within the cluster containing H1821+643, but is too weak to explain the large amount of gas cooling seen.
Dr Thomas Braben, an astronomer at the University of Nottingham, said: “This black hole may not be producing enough because it isn't pumping any heat into its surroundings, but the current situation won't last forever.'' ” he said.
“Ultimately, the rapid uptake of fuel by the black hole should increase the jet's power and strongly heat the gas.”
“After that, the growth of the black hole and its galaxy should slow down significantly.”
team's paper will be published in Royal Astronomical Society Monthly Notices.
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HR Russell other. 2024. Cooling flow around low-redshift quasar H1821+643. MNRAS, in press. arXiv: 2401.03022
Source: www.sci.news
