Black hole collisions explained by new simulations of OJ 287 system
OJ 287 displays light bursts equivalent to one trillion suns approximately every 12 years. Astronomers now attribute these phenomena to a binary system of supermassive black holes. The secondary black hole repeatedly passes through the disk of gas surrounding the primary, disrupting its structure and generating outflows and bursts of light.
Sean Ressler, a postdoctoral researcher at CITA, led a study presenting the first comprehensive simulations of OJ 287. The research, co-authored by Luciano Combi, Bart Ripperda, and Xinyu Li, modeled complex interactions between gravity, electromagnetism, and fluid dynamics associated with these collisions.
"These simulations take into account the complicated interaction between extreme gravity, electrodynamics, and fluid dynamics in order to rigorously test whether or not the model can actually explain the observed outbursts," Combi said. "This is the first time the gas (which produces the light) around the binary hole has been simulated all together."
The principal black hole in OJ 287 has a mass of approximately 18 billion times that of the sun, while the companion is about 150 million solar masses. The team's work provides evidence that collisions within the disk produce sufficient energy to explain the observed bursts, and the resulting disturbances warp the disk and create spiral patterns.
Ressler stated, "These calculations should really be treated as a first step towards fully realistic simulations. We still need to include the effects of how the flashes of light are produced and then get bent by the extreme gravity of the black holes. We also made a few simplifications to make the simulations more feasible, but in the end, we expect to remove these simplifications and account for the behaviour of light. This is a step towards a fully coherent picture of the system."
The researchers note connections to gravitational waves: the intense gravity from these massive black holes generates space-time ripples that may be detectable by future pulsar timing arrays. Combining gravitational wave data with traditional telescope findings will enhance understanding of galaxy mergers, black hole physics, and cosmic growth.
Bart Ripperda commented, "combining the information that we would get from these gravitational waves with the information we get from traditional telescopes will lead to major breakthroughs in our understanding of gravity, black holes, and how galaxies grow over time. Realistic simulations will be crucial in predicting electromagnetic signatures from the plasma physics near the event horizon."
Research Report:Black Hole Collisions With Thin Accretion Disks: OJ 287 and Small-Mass-Ratio Supermassive Black Hole Binary Candidates
Related Links
Canadian Institute for Theoretical Astrophysics
Understanding Time and Space
