Nav: Home

Supermassive black hole model predicts characteristic light signals at cusp of collision

February 14, 2018

A new simulation of supermassive black holes--the behemoths at the centers of galaxies--uses a realistic scenario to predict the light signals emitted in the surrounding gas before the masses collide, said Rochester Institute of Technology researchers.

The RIT-led study represents the first step toward predicting the approaching merger of supermassive black holes using the two channels of information now available to scientists--the electromagnetic and the gravitational wave spectra--known as multimessenger astrophysics. The findings appear in the paper "Quasi-periodic Behavior of Mini-disks in Binary Black Holes Approaching Merger," published in the Astrophysical Journal Letters.

"We've performed the first simulation in which an accretion disk around a binary black hole feeds individual accretion disks, or mini-disks, around each black hole in general relativity and magnetohydrodynamics," said Dennis Bowen, lead author and postdoctoral researcher at RIT's Center for Computational Relativity and Gravitation.

Unlike their less massive cousins, first detected in 2016, supermassive black holes are fed by gas disks that surround them like doughnuts. The strong gravitational pull of the black holes that inspiral toward one another heats and disrupts the flow of gas from disk to black hole and emits periodic signals in the visible to X-ray portions of the electromagnetic spectrum.

"We have not yet seen two supermassive black holes get this close," Bowen said. "It provides the first hints of what these mergers will look like in a telescope. The filling and refilling of mini-disks affect the light signatures."

The simulation models supermassive black holes in a binary pair, each surrounded by its own gas disks. A much larger gas disk encircles the black holes and disproportionately feeds one mini-disk over another, leading to the filling-and-refilling cycle described in the paper.

"The evolution is long enough to study what the real science outcome would look like," said Manuela Campanelli, director of the Center for Computational Relativity and Gravitation and a co-author on the paper.

Binary supermassive black holes emit gravitational waves at lower frequencies than stellar-mass black holes. The ground-based Laser Interferometer Gravitational-wave Observatory, in 2016, detected the first gravitational waves from stellar mass black holes collisions with an instrument tuned to higher frequencies. LIGO's sensitivity is unable to observe the gravitational wave signals produced by supermassive black hole coalescence.

The launch of the space-based Laser Interferometer Space Antenna, or LISA, slated for the 2030s, will detect gravitational waves from colliding supermassive black holes in the cosmos. When operational in the 2020s, the ground-based Large Synoptic Survey Telescope, or LSST, under construction in Cerro Pachón, Chile, will produce the widest, deepest survey of light emissions in the universe. The pattern of signals predicted in the RIT study could guide scientists to orbiting pairs of supermassive black holes.

"In the era of multimessenger astrophysics, simulations such as this are necessary to make direct predictions of electromagnetic signals that will accompany gravitational waves," Bowen said. "This is the first step toward the ultimate goal of simulations capable of making direct predictions of the electromagnetic signal from binary black holes approaching merger."

Bowen and his collaborators combined simulations from RIT's Black Hole Lab computer clusters and the Blue Waters supercomputer at the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign, one of the largest supercomputers in the United States.

Astrophysicists from RIT, Johns Hopkins University and NASA Goddard Space Flight Center collaborated on the project. The publication is based on Bowen's Ph.D. dissertation at RIT and completes research begun by a co-author, Scott Noble, a former RIT post-doctoral researcher, now at NASA Goddard. Their research is part of a collaborative National Science Foundation-funded project led by Campanelli. Co-authors include Vassilios Mewes, RIT postdoctoral researcher; Miguel Zilhao, former RIT post-doctoral researcher, now at Universidade de Lisboa, in Portugal; and Julian Krolik, professor of physics and astronomy at Johns Hopkins University.

In an upcoming paper, the authors will explore further the correlation between gas flowing in and out of the accretion disks and fluctuating light emissions. They will present predictions of light signatures scientists can expect to see with advanced telescopes when looking for supermassive black holes approaching merger.
-end-


Rochester Institute of Technology

Related Black Hole Articles:

Scientists make waves with black hole research
Scientists at the University of Nottingham have made a significant leap forward in understanding the workings of one of the mysteries of the universe.
Collapsing star gives birth to a black hole
Astronomers have watched as a massive, dying star was likely reborn as a black hole.
When helium behaves like a black hole
A team of scientists has discovered that a law controlling the bizarre behavior of black holes out in space -- is also true for cold helium atoms that can be studied in laboratories.
Star in closest orbit ever seen around black hole
Astronomers have found evidence of a star that whips around a likely black hole twice an hour.
Tail of stray black hole hiding in the Milky Way
By analyzing the gas motion of an extraordinarily fast-moving cosmic cloud in a corner of the Milky Way, Astronomers found hints of a wandering black hole hidden in the cloud.
Hubble gazes into a black hole of puzzling lightness
The beautiful spiral galaxy visible in the center of the image is known as RX J1140.1+0307, a galaxy in the Virgo constellation imaged by the NASA/ESA Hubble Space Telescope, and it presents an interesting puzzle.
Clandestine black hole may represent new population
Astronomers have combined data from NASA's Chandra X-ray Observatory, the Hubble Space Telescope and the National Science Foundation's Karl G.
When will a neutron star collapse to a black hole?
Astrophysicists from Goethe-University Frankfurt have found a simple formula for the maximum mass of a rotating neutron star and hence answered a question that had been open for decades.
Behemoth black hole found in an unlikely place
Astronomers have uncovered a near-record breaking supermassive black hole, weighing 17 billion suns, in an unlikely place: in the center of a galaxy in a sparsely populated area of the universe.
Behemoth black hole found in an unlikely place
Astronomers have uncovered one of the biggest supermassive black holes, with the mass of 17 billion Suns, in an unlikely place: the centre of a galaxy that lies in a quiet backwater of the Universe.

Related Black Hole 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

Jumpstarting Creativity
Our greatest breakthroughs and triumphs have one thing in common: creativity. But how do you ignite it? And how do you rekindle it? This hour, TED speakers explore ideas on jumpstarting creativity. Guests include economist Tim Harford, producer Helen Marriage, artificial intelligence researcher Steve Engels, and behavioral scientist Marily Oppezzo.
Now Playing: Science for the People

#524 The Human Network
What does a network of humans look like and how does it work? How does information spread? How do decisions and opinions spread? What gets distorted as it moves through the network and why? This week we dig into the ins and outs of human networks with Matthew Jackson, Professor of Economics at Stanford University and author of the book "The Human Network: How Your Social Position Determines Your Power, Beliefs, and Behaviours".