Nav: Home

Simulating supermassive black holes

March 30, 2016

Near the edge of the visible Universe are some of the brightest objects ever observed, known as quasars, which are believed to contain supermassive black holes of more than a billion times the mass of our Sun. Simulations by Kentaro Nagamine at Osaka University's Department of Earth and Space Science, Isaac Shlosman at the University of Kentucky and co-workers have revealed for the first time exactly how these black holes formed 700 million years after the Big Bang.

"The early Universe was a dense, hot and uniform plasma," explains Nagamine. "As it cooled, fluctuations in the mass distribution formed seeds around which matter could gather due to gravity." These are the origins of the first stars. Similar processes might have later seeded the growth of bigger structures such as supermassive black holes.

Until recently, many researchers thought supermassive black holes were seeded by the collapse of some of the first stars. But modeling work by several groups has suggested that this process would only lead to small black holes. Nagamine and co-workers simulated a different situation, in which supermassive black holes are seeded by clouds of gas falling into potential wells created by dark matter -- the invisible matter that astronomers believe makes up 85% of the mass of the Universe.

Simulating the dynamics of huge gas clouds is extremely complex, so the team had to use some numerical tricks called 'sink particles' to simplify the problem.

"Although we have access to extremely powerful supercomputers at Osaka University's Cybermedia Center and the National Astronomical Observatory of Japan, we can't simulate every single gas particle," explains Nagamine. "Instead, we model small spatial scales using sink particles, which grow as the surrounding gas evolves. This allows us to simulate much longer timescales than was previously possible."

The researchers found that most seed particles in their simulations did not grow very much, except for one central seed, which grew rapidly to more than 2 million Sun-masses in just 2 million years, representing a feasible path toward a supermassive black hole. Moreover, as the gas spun and collapsed around the central seed it formed two misaligned accretion discs, which have never been observed before.

In other recent work, Nagamine and co-workers described the growth of massive galaxies that formed around the same time as supermassive black holes [1]. "We like to push the frontier of how far back in time we can see," says Nagamine. The researchers hope their simulations will be validated by real data when NASA's James Webb Space Telescope, due to be launched in 2018, observes distant sources where direct gas collapse is happening.
-end-
1. Yajima, H., Shlosman, I., Romano-Díaz, E. & Nagamine, K. Observational properties of simulated galaxies in overdense and average regions at redshifts z?6-12. Monthly Notices of the Royal Astronomical Society 451, 418-432 (2015).

Osaka University

Related Supermassive Black Holes Articles:

Astronomers detect orbital motion in pair of supermassive black holes
Images made with the continent-wide Very Long Baseline Array detect the orbital motion of two supermassive black holes as they circle each other at the center of a distant galaxy.
Groundbreaking discovery confirms existence of orbiting supermassive black holes
For the first time ever, astronomers at The University of New Mexico say they've been able to observe and measure the orbital motion between two supermassive black holes hundreds of millions of light years from Earth -- a discovery more than a decade in the making.
Extremely fine measurements of motion in orbiting supermassive black holes
After 12 years observing black holes at the center of an amalgam of ancient galaxies, a multi-institution team, including Stanford's Roger Romani, may have recorded the smallest-ever movement of an object across the sky.
VLA reveals new object near supermassive black hole in famous galaxy
When astronomers took a new look at a famous galaxy with the upgraded Very Large Array, they were surprised by the appearance of a new, bright object that had not appeared in previous images.
Supermassive black holes found in 2 tiny galaxies
U astronomers and colleagues have found two ultra-compact dwarf galaxies with supermassive black holes, the second and third such galaxies found to harbor the objects.
Stars born in winds from supermassive black holes
Observations using ESO's Very Large Telescope have revealed stars forming within powerful outflows of material blasted out from supermassive black holes at the cores of galaxies.
Hubble detects supermassive black hole kicked out of galactic core
An international team of astronomers using the NASA/ESA Hubble Space Telescope have uncovered a supermassive black hole that has been propelled out of the centre of the distant galaxy 3C186.
Breaking the supermassive black hole speed limit
A new computer simulation helps explain the existence of puzzling supermassive black holes observed in the early universe.
New model explains the formation of supermassive black holes in the very early universe
Simulations performed using supercomputers demonstrate that the radiation from nearby galaxies can facilitate the formation of supermassive black hole seeds in nearby gas clouds.
Changes of supermassive black hole in the center of NGC 2617 galaxy
Scientists have been studying changes in the appearance of emission from around the supermassive black hole in the center of a galaxy known to astronomers as NGC 2617.

Related Supermassive Black Holes Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Digital Manipulation
Technology has reshaped our lives in amazing ways. But at what cost? This hour, TED speakers reveal how what we see, read, believe — even how we vote — can be manipulated by the technology we use. Guests include journalist Carole Cadwalladr, consumer advocate Finn Myrstad, writer and marketing professor Scott Galloway, behavioral designer Nir Eyal, and computer graphics researcher Doug Roble.
Now Playing: Science for the People

#530 Why Aren't We Dead Yet?
We only notice our immune systems when they aren't working properly, or when they're under attack. How does our immune system understand what bits of us are us, and what bits are invading germs and viruses? How different are human immune systems from the immune systems of other creatures? And is the immune system so often the target of sketchy medical advice? Those questions and more, this week in our conversation with author Idan Ben-Barak about his book "Why Aren't We Dead Yet?: The Survivor’s Guide to the Immune System".