A rare triple quasar is one of the most massive objects in the universe

Supermassive black holes are the most massive objects in the universe. Its mass can reach millions and billions of solar masses. Supercomputer simulations on the Texas Advanced Computing Center’s (TACC) Frontera supercomputer have helped astrophysicists uncover the origin of supermassive black holes that formed about 11 billion years ago.

“We found that one possible formation channel for supermassive black holes is from the intense mergers of massive galaxies that most likely occur in the ‘cosmic noon’ era,” said Yuying Ni, a postdoctoral fellow at the Smithsonian Institution for Astrophysics.

Ni is the lead author of the work published in Astrophysical Journal Letters In December 2022, supermassive black holes were found to have formed from the merger of ternary quasars, systems of three galactic nuclei illuminated by gas and dust falling into a supermassive intervening black hole.

Working in conjunction with the telescope’s data, the computational simulation helps astrophysicists fill in missing parts of the origins of stars and exotic objects like black holes.

It is called one of the largest cosmic simulations to date AstridCo-developed by Ni. It is the largest simulation in terms of particle size, or memory load, in the field of galaxy formation simulations.

She explained that “Astrid’s scientific goal is to study the formation of galaxies, the mergers of supermassive black holes, and reionization over the course of cosmic history.” Astrid models large volumes of the universe spanning hundreds of millions of light-years, yet she can zoom in to very high resolution.

Developed by Ni Astrid using the Frontera supercomputer of the Texas Advanced Computing Center (TACC), it is the most powerful academic supercomputer in the United States.

Frontera is the only system we’ve done [in] Astrid from the first day. It’s a pure simulation based on Frontera,” Ni continued.

Frontera is ideal for Ni’s Astrid simulations because of its ability to support large applications that need thousands of computation nodes and individual physical systems of processors and memory harnessed together for some of the most difficult scientific computations.

“We used 2048 nodes, the maximum allowed in the large queue, to launch these simulations on a routine basis. This is only possible on large supercomputers like Frontera,” Ni said.

My findings from Astrid’s simulation show something completely mind-boggling – the formation of black holes can reach a theoretical upper limit of 10 billion solar masses. “It’s a very difficult computational task. But you can only capture these rare and extreme objects with large-scale simulations,” Ni said.

“What we found are three supermassive black holes that gathered their mass during the cosmic noon, which is the time 11 billion years ago when star formation, active galactic nuclei (AGN) and supermassive black holes in general reached their peak activity,” he added.

About half of all stars in the universe were born during a cosmic noon. Evidence for this comes from multi-wavelength data from several galaxy surveys such as the Great Observations Origins Deep Survey, where spectra from distant galaxies tell the ages of their stars, the formation history of the stars, and the chemical elements of the stars within.

“In this era, we detected an intense and relatively rapid merger of three massive galaxies,” Ni said. “The mass of each galaxy is 10 times that of our own Milky Way, and there is a supermassive black hole at the center of each galaxy. Our findings show the possibility that these triple quasar systems are the ancestors of those rare supermassive black holes. , after these three interact force of gravity and merge with each other.

Moreover, new observations of galaxies at cosmic noon will help reveal the merger of supermassive black holes and the formation of supermassive holes. Data is now rolling in from the James Webb Space Telescope (JWST), with high-resolution detail of galaxy shapes.

“We are following a model of feedback from the JWST data from the Astrid simulation,” said Ni.

“In addition, NASA’s Laser Interferometer Space Telescope (LISA) Observatory will give us a better understanding of how these massive black holes merge and/or merge, along with their hierarchical structure, composition, and galaxy mergers over the course of cosmic history.” “This is an exciting time for astrophysicists, and it’s good that we have simulations to allow for theoretical predictions of those observations.”

The Ni research group also plans to systematically study the host AGN of galaxies in general. “It is a very important science objective for JWST, as it determines what the AGN’s host galaxies look like and how they differ compared to the vast galaxy population during the cosmic noon,” she added.

“It’s great to have access to supercomputers, technology that allows us to model a swath of the universe in great detail and make predictions from observations,” Ni said.