Some of the gas erupts from the supermassive black hole located at the center of galaxy cluster SDSS J1531+3414 (abbreviated SDSS J1531) until it reaches a temperature high enough to form numerous star clusters. Cooled down.
Multi-wavelength image of the massive galaxy cluster SDSS J1531+3414.Image credits: NASA / CXC / SAO / Omorui other. / STScI / Tremblay other. / Astron / Loafers / NASA / CXC / SAO / N. Walk.
SDSS J1531 is a huge galaxy cluster containing hundreds of individual galaxies and a huge reservoir of hot gas and dark matter.
At the center of SDSS J1531, two of the cluster's largest galaxies collide with each other.
Surrounding these merging giants are 19 large star clusters called superclusters, arranged in an “S” shape similar to beads on a string.
Dr. Osase Omoruyi and colleagues at Harvard University and the Smithsonian Center for Astrophysics are using NASA's Chandra X-ray Observatory, the LOFAR radio network, and other telescopes to discover how this chain of unusual star clusters formed. I found out what happened.
The discovery of evidence of an ancient mega-eruption in SDSS J1531 provided important clues.
The eruption may have occurred when a supermassive black hole at the center of one of the large galaxies produced a very powerful jet.
As the jet traveled through space, it pulled surrounding hot gas away from the black hole, creating a huge cavity.
“We're already observing this system as it existed 4 billion years ago, when the Earth was just forming,” Omoruyi said.
“This ancient cavity is a fossil of the black hole's influence on its host galaxy and its surroundings, and tells us about important events that occurred almost 200 million years ago in the history of this star cluster.”
Evidence for the cavity comes from bright X-ray emission “wings” seen on Chandra that track dense gas near the center of SDSS J1531.
These wings form the edges of the cavity, and the less dense gas between them is part of the cavity.
LOFAR shows radio waves from the remains of the jet's energetic particles filling a huge cavity.
Taken together, these data provide convincing evidence for an ancient great explosion.
Astronomers also discovered cold and warm gas near the cavity's opening, detected by the Atacama Large Millimeter and Submillimeter Array (ALMA) and Gemini North Telescope, respectively.
They argue that some of the hot gas pushed out of the black hole eventually cooled down to cold, warm gas.
They believe that the tidal effects of the two galaxies merging compressed the gas along a curved path, forming the star cluster in a “string-bead” pattern.
“We reconstructed the sequence of events that may have occurred within this cluster over a wide range of distances and times,” said Dr. Grant Tremblay, also of Harvard University and the Smithsonian Center for Astrophysics.
“It started when a black hole, just one light-year in diameter, formed a cavity about 500,000 light-years wide.”
“This single event triggered the formation of young star clusters almost 200 million years later, each several thousand light-years in diameter.”
Although the authors only looked at the radio waves and cavity from one jet, black holes typically fire two jets in opposite directions.
They also observed radio emissions further out from the galaxy that could be the remains of a second jet, but it was unrelated to the detected cavity.
They speculate that radio and X-ray signals from other eruptions may have diminished to the point where they could no longer be detected.
“We believe the evidence for this large-scale eruption is strong, but further observations from Chandra and LOFAR will confirm the case,” Dr. Omoruyi said.
“We hope to learn more about the origins of the cavities we have already detected and find the cavities we expect to find on the other side of the black hole.”
a paper Regarding the survey results, astrophysical journal.
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Omase Omorui other. 2024. A “string bead” star formation associated with one of the most powerful she-AGN outbursts observed in the Cool Core Galaxy Cluster. APJ, in press. arXiv: 2312.06762
