Astronomers using the NASA/ESA/CSA James Webb Space Telescope discovered that just 740 million years ago, two galaxies and their central black hole (a galaxy known as ZS7) We have found evidence that a merger is underway.
This image shows the location of the galaxy ZS7. Image credits: NASA / ESA / CSA / Webb / J. Dunlop / D. Magee / PG Perez-Gonzalez / H. Ubler / R. Maiolino.
Supermassive black holes that are actively accreting matter have unique spectroscopic signatures that allow astronomers to identify them.
For very distant galaxies like the one in this study, these signatures are inaccessible from the ground and can only be seen in the web.
Dr. Hanna Ubler said: “We found evidence of very dense gas in fast motion near the black hole, as well as at high temperatures illuminated by the high-energy radiation that black holes typically produce during accretion. “We also found evidence of highly ionized gas.” Astronomer at Cambridge University.
“Thanks to Webb's unprecedented sharp imaging capabilities, our team was able to spatially separate the two black holes.”
Astronomers have discovered that one of the two black holes has a mass 50 million times that of the Sun.
Dr Roberto Maiolino, an astronomer at the University of Cambridge and University College London, said: “The mass of the other black hole is probably similar, but this second black hole is buried in dense gas.'' Therefore, it is much more difficult to measure.”
“Our findings suggest that mergers are an important pathway for black holes to grow rapidly, even at the dawn of the universe,” said Dr. Ubler.
“Together with Webb's other discoveries of active massive black holes in the distant Universe, our results also show that massive black holes have been shaping the evolution of galaxies from the beginning. ”
“The mass of the stars in this system that we studied is similar to the mass of the nearby Large Magellanic Cloud,” said Dr. Pablo G. Pérez González, an astronomer at the Astrobiologia Center.
“You can imagine how the merging evolution of galaxies would be affected if each galaxy had one supermassive black hole as large or larger than the one in the Milky Way.”
Researchers also note that gravitational waves are also generated when two black holes merge.
Such phenomena will be detectable by the next generation of gravitational-wave observatories, such as ESA's upcoming Laser Interferometer Space Antenna (LISA) mission.
“Webb's results show that light objects detectable by LISA should be much more frequent than previously assumed,” said LISA lead project scientist and ESA astronomer Nora. Dr. Luetzgendorf said.
“We'll probably tune our models for LISA velocities in this mass range. This is just the tip of the iceberg.”
This finding is reported in the following article: paper inside Royal Astronomical Society Monthly Notices.
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Hannah Uebler other. 2024. GA-NIFS: JWST discovers AGN offset 740 million years after the Big Bang. MNRAS 531 (1): 355-365; doi: 10.1093/mnras/stae943
Source: www.sci.news
