In a new paper published on 16 November 2017, the LIGO Scientific Collaboration and the Virgo Collaboration announced another gravitational wave discovery – this time the collision of the lightest pair of binary black holes seen by the collaborations’ detectors since the first detection in February 2016.
The merger of two relatively light black holes, seven and 12 times the mass of the Sun, was detected by the two LIGO detectors at 02:01:16 UTC Jon June 8 2017, and left behind a final black hole 18 times the mass of the Sun. This means that energy equivalent to about 1 solar mass was radiated away as gravitational waves during the merger.
As with previous detections, researchers from the University of Glasgow’s School of Physics and Astronomy and Institute for Gravitational Research played a key role in analysing the data from the detectors.
Prof Sheila Rowan, director of the Institute for Gravitational Research, said: “our most recent observing run is still giving us new surprises – and extending the black hole family tree into new branches.”
Professor Martin Hendry, head of the University’s School of Physics and Astronomy, said: “This latest discovery will help astronomers to better compare and contrast the properties of black holes observed with gravitational waves with the properties of similar-mass black holes previously detected indirectly with X-ray observations.”
Professor James Hough said: “This low-mass merger event provides us with another invaluable glimpse into the workings of black holes which would be impossible without gravitational wave astronomy.”
Dr John Veitch said: “GW170608 is the lightest pair of black holes that we have detected so far, which provides us with new opportunities to explore the crossover between gravitational wave astronomy and more conventional forms of astronomy.”