First detected merger of black hole and neutron star

Astronomers have for the first time detected a black hole eating a ‘Pac Man’ neutron star, a milestone that documents the collision of the two most extreme and enigmatic objects in the Universe. The Laser Interferometer Gravitational Wave Observatory (LIGO), in the United States, and the Virgo gravitational wave observatory, in Italy, have captured the gravitational waves coming from the death spiral and the merger of a neutron star with a hole. ..

The Laser Interferometer Gravitational Wave Observatory (LIGO), in the United States, and the Virgo gravitational wave observatory, in Italy, have captured gravitational waves from the death spiral and the merger of a neutron star with a black hole , not once but twice, as published in ‘The Astrophysical Journal Letters’.

Researchers say their observations will help unravel some of the universe’s most complex mysteries, such as the components of matter and the workings of space and time. More than 1,000 scientists participated in the world’s first detections, and many of them from Australia, such as the Australian National University, led the process.

Distinguished Professor Susan Scott, co-author of the study based at the ANU School of Physics Research at the Center for Gravitational Astrophysics, said the events occurred about a billion years ago, but were so massive that we can still observe their ripples. gravitational today. “These collisions have shaken the Universe to its core and we have detected the waves they have sent through the cosmos,” she explains in a statement.

“These collisions have shaken the Universe to its core and we have detected the waves they have sent through the cosmos – he explains in a statement -. Each collision is not just the meeting of two massive and dense objects. It is really like the Pac -Man, with a black hole that swallows its companion neutron star. “

“These are extraordinary events and we have waited a long time to witness them,” he continues. “So it is incredible to be able to finally capture them.”

One of the events included a black hole with a mass nine times that of our own sun and a neutron star with a mass twice that of our sun. The other event included a black hole with about six times the mass of our sun and a neutron star with 1.5 times its mass.

Professor Scott, also a senior researcher at the ARC’s Center of Excellence for the Discovery of Gravitational Waves (OzGrav), notes that the international team had previously captured many collision events of two black holes, as well as two colliding neutron stars.

“We have now completed the last piece of the puzzle with the first confirmed observations of gravitational waves from the collision of a black hole and a neutron star,” he notes.

Dr. Johannes Eichholz, from the ANU Center for Gravitational Astrophysics and a research associate at OzGrav, said the two detections were originally made on January 5 and 15, 2020.

“These types of detections are incredibly rare – he says -. We have not detected these events once but twice and 10 days apart. Like the waves of these two events, which have been felt a billion years later. , these findings will have a profound impact on our understanding of the Universe for many years to come. “