. | . |
RIT scientists contribute to the first discovery of an intermediate-mass black hole by Staff Writers Rochester NY (SPX) Sep 10, 2020
The LIGO Scientific Collaboration and the Virgo Collaboration recently announced the discovery of GW190521, the most massive gravitational wave binary observed to date, and Rochester Institute of Technology scientists played an important role in identifying and analyzing the event. They detected the signal with the National Science Foundation's Laser Interferometer Gravitational-wave Observatory (LIGO). The two inspiralling black holes had masses of about 85 and 66 solar masses, and resulted in the formation of a black hole remnant of 142 solar masses, providing the first clear detection of an "intermediate-mass" black hole. "We're seeing something more massive than we've seen before, past the point where we thought that we could form black holes," said Associate Professor Richard O'Shaughnessy, a member of CCRG and the LIGO Scientific Collaboration. "It's therefore suggesting that our previous understanding was incomplete or maybe there's more out there than we previously envisioned." Not only were the black holes in this event larger than those detected previously, the signal indicates that they could have been spinning about their own axes, at angles that were out of alignment with the axis of their orbit. The black holes' misaligned spins likely caused their orbits to wobble, or "precess," as the they spiraled toward each other. Jacob Lange '20 Ph.D. (astrophysical sciences and technology) is a recent alum who contributed heavily to the analysis, using RIT-developed parameter estimation code and direct comparisons to numerical relativity simulations to estimate and corroborate the unique features of the event, including the masses and spin of the black holes. He said he is excited about the discovery because it challenges previous assumptions about black hole formation and raises important new questions about the fundamentals of how gravity works. "We thought it would be almost impossible for us to measure precession at this high mass but somehow we were able to do it and it's not really clear why that was the case," said Lange. "It's not what we expected to be able to detect and hopefully we can learn a lot more from it." The discovery and its implications are outlined in two papers published in Physical Review Letters and The Astrophysical Journal Letters and 10 researchers from RIT's Center for Computational Relativity and Gravitation are listed among the authors. RIT's contributions also included providing computer simulations of Albert Einstein's equations by co-authors Professor Carlos Lousto and Research Associate James Healy used to compare the signal with and developing a waveform catalog. While previous black holes detected by the European Virgo and the U.S. National Science Foundation LIGO are believed to have formed by collapsing stars, theory suggests that black holes with masses between 65 and 120 times the mass of the sun cannot be formed by this method. This perhaps means that intermediate black holes may form by another method, such as Pacman-like behavior where black holes grow by merging with smaller black holes.
Brazilian researcher proposes universal mechanism for ejection of matter by black holes Sao Paulo, Brazil (SPX) Sep 03, 2020 Black holes can expel a thousand times more matter than they capture. The mechanism that governs both ejection and capture is the accretion disk, a vast mass of gas and dust spiraling around the black hole at extremely high speeds. The disk is hot and emits light as well as other forms of electromagnetic radiation. Part of the orbiting matter is pulled toward the center and disappears behind the event horizon, the threshold beyond which neither matter nor light can escape. Another, much larger, part is ... read more
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |