Overview

• The GW231123 event, detected on November 23, 2023, fused roughly 100 and 140 solar-mass black holes into a 225-solar-mass object, marking the largest merger observed to date.
• Preliminary analysis shows the progenitor black holes spun near the maximum rate allowed by general relativity, underscoring the detectors’ precision in capturing a 0.1-second signal.
• Presented at the GR24 and Edoardo Amaldi conferences in Glasgow, the findings challenge the predicted mass gap by suggesting hierarchical assembly in dense stellar clusters.
• This detection boosts the LIGO-Virgo-KAGRA network’s catalog to about 300 gravitational-wave signals since the first 2015 observation, reflecting rapid advances in sensitivity and collaboration.
• The upcoming public data release will enable researchers worldwide to probe the event’s implications for stellar evolution models and black hole growth scenarios.