A team of scientists with the LIGO-Virgo-KAGRA (LVK) Collaboration has made a groundbreaking discovery, detecting the merger of two massive black holes that have produced a final black hole approximately 225 times the mass of our Sun. This finding is not only a record-breaker but also presents significant challenges to current theoretical models and pushes the limits of gravitational-wave detection technology.
The signal, designated GW231123, was detected during the fourth observing run of the LVK network on November 23, 2023. The merger involved two black holes with masses approximately 100 and 140 times that of the Sun, resulting in a massive final black hole.
“This is the most massive black hole binary we’ve observed through gravitational waves, and it presents a real challenge to our understanding of black hole formation,” said Mark Hannam, a member of the LVK Collaboration. “Black holes this massive are forbidden through standard stellar evolution models. One possibility is that the two black holes in this binary formed through earlier mergers of smaller black holes.”
The detection of GW231123 demonstrates the unique capabilities of gravitational wave astronomy. The high mass and rapid spinning of the black holes push the limits of both technology and theoretical models, requiring advanced simulations to extract accurate information from the signal.
Researchers are continuing to refine their analysis and improve models to better understand this extreme event. “It will take years for the community to fully unravel this intricate signal pattern and all its implications,” said Gregorio Carullo, a member of the LVK Collaboration.
The discovery highlights the importance of continued collaboration among scientists from around the world. The LIGO-Virgo-KAGRA Collaboration consists of over 1,600 scientists participating in the effort, with additional partners contributing to the project.
GW231123 will be presented at the 24th International Conference on General Relativity and Gravitation (GR24) and the 16th Edoardo Amaldi Conference on Gravitational Waves, scheduled for July 14-18, 2025. The calibrated data used to detect and study GW231123 will be made available for other researchers to analyze through the Gravitational Wave Open Science Center (GWOSC).
Source: https://www.caltech.edu/about/news/ligo-detects-most-massive-black-hole-merger-to-date