RIT scientists measure black hole's tilt and spin for clues to how massive stars die

June 01, 2017

Rochester Institute of Technology researchers continue to make significant contributions to gravitational wave astronomy, with the third detection of gravitational waves and a new black hole 49 times the size of our sun.

The LIGO collaboration today announced results from the detection of gravitational waves on Jan. 4. The discovery will be published in the journal Physical Review Letters.

RIT scientists helped the collaboration measure and interpret black hole spins and their alignment. These measurements can tell scientists what happens when massive stars die and transform into black holes.

The gravitational wave signal was produced from the collision of black holes. The newly found black hole, formed by the merger, has a mass about 49 times that of our sun. This fills in a gap between the masses of the two merged black holes detected previously by LIGO, with solar masses of 62 (first detection) and 21 (second detection).

"We can see the outlines of a population of black holes emerge," said Richard O'Shaughnessy, associate professor in RIT's School of Mathematical Sciences.

The LIGO paper cites O'Shaughnessy's upcoming research, which was used in part, to help interpret the most recent event. He will present his work at the American Astronomical Society on June 5 in Austin, Texas.

The new observations rule out the possibility that pairs of heavy black holes have a lot of net-aligned spin and agree with LIGO's 2015 breakthrough observation, he noted.

"That's either because heavy black hole spins are small, or because they're tilted, so their net effect cancels out," O'Shaughnessy said. "Different teams have made different predictions for black hole spins. The most extreme predictions are ruled out. As for the others, time will tell."

Research at RIT's Center for Computational Relativity and Gravitation is advancing techniques for understanding that crucial astrophysical parameter--spin, said Carlos Lousto, professor in RIT's School of Mathematical Sciences.

"At RIT, we are working on improving the spin measurements of the black holes by solving to high accuracy Einstein's equations and directly comparing those theoretical predictions with LIGO's observed signals," Lousto said.

Researchers in RIT's Center for Computational Relativity and Gravitation directly compared gravitational wave signals to their computer simulations based on Albert Einstein's equations. The recent observations further tested Einstein's general theory of relativity and prediction that gravitational waves always move at the speed of light. LIGO saw no evidence that the waves travelled at different speeds.

"This third event lies in an mass range intermediate to the previous two events and shows that black hole mergers are common in the universe," said Manuela Campanelli, director of RIT's Center for Computational Relativity and Gravitation and Frontier in Gravitational Astrophysics, an RIT signature research area.

RIT members of the LIGO Scientific Collaboration include O'Shaughnessy, Campanelli, Lousto, Yosef Zlochower, John Whelan, Hans-Peter Bischof, James Healy, Brennan Ireland, Jacob Lange, Daniel Wysocki, Andrew Williamson, Yuanhao Zhang and Monica Rizzo. The international collaboration has about 1,000 members who perform LIGO research together with the European-based Virgo Collaboration.

The new detection occurred during LIGO's current observing run, which began Nov. 30, 2016, and will continue through the summer. LIGO observations are carried out by twin detectors--one in Hanford, Wash., and the other in Livingston, La.--operated by Caltech and Massachusetts Institute of Technology with funding from the National Science Foundation.

LIGO made the first-ever direct observation of gravitational waves in September 2015 and a second detection in December 2015. The breakthrough LIGO paper prominently cites 2005 landmark research done by Campanelli and her team on binary black hole mergers. Based on this milestone work, Lousto and Healy numerically modeled the merger of a pair of black holes and simulated gravitational waveforms that match the first LIGO detection.
LIGO is funded by the National Science Foundation, and operated by MIT and Caltech, which conceived and built the project. Financial support for the Advanced LIGO project was led by NSF with Germany (Max Planck Society), the U.K. (Science and Technology Facilities Council) and Australia (Australian Research Council) making significant commitments and contributions to the project. More than 1,000 scientists from around the world participate in the effort through the LIGO Scientific Collaboration, which includes the GEO Collaboration. LIGO partners with the Virgo Collaboration, a consortium including 280 additional scientists throughout Europe supported by the Centre National de la Recherche Scientifique,, the Istituto Nazionale di Fisica Nucleare,, and Nikhef, as well as Virgo's host institution, the European Gravitational Observatory. Additional partners are listed at http://ligo.org/partners.php.

Rochester Institute of Technology

Related Black Holes Articles from Brightsurf:

The black hole always chirps twice: New clues deciphering the shape of black holes
A team of gravitational-wave scientists led by the ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav) reveal that when two black holes collide and merge, the remnant black hole 'chirps' not once, but multiple times, emitting gravitational waves--intense ripples in the fabric space and time--that inform us about its shape.

Black holes? They are like a hologram
Spherical, smooth and simple according to the theory of relativity, or extremely complex and full of information as, according to quantum laws, Stephen Hawking used to say?

Under pressure, black holes feast
A new, Yale-led study shows that some supermassive black holes actually thrive under pressure.

Staining cycles with black holes
In the treatment of tumors, microenvironment plays an important role.

Black holes sometimes behave like conventional quantum systems
A group of Skoltech researchers led by Professor Anatoly Dymarsky have studied the emergence of generalized thermal ensembles in quantum systems with additional symmetries.

Scientists may have discovered whole new class of black holes
New research shows that astronomers' search for black holes might have been missing an entire class of black holes that they didn't know existed.

Are black holes made of dark energy?
Two University of Hawaii at Manoa researchers have identified and corrected a subtle error that was made when applying Einstein's equations to model the growth of the universe.

Telescopes in space for even sharper images of black holes
Astronomers have just managed to take the first image of a black hole, and now the next challenge facing them is how to take even sharper images, so that Einstein's Theory of General Relativity can be tested.

Can entangled qubits be used to probe black holes?
Information escapes from black holes via Hawking radiation, so it should be possible to capture it and use it to reconstruct what fell in: if given time longer than the age of the universe.

How black holes power plasma jets
Cosmic robbery powers the jets streaming from a black hole, new simulations reveal.

Read More: Black Holes News and Black Holes Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.