Observation of Gravitational Waves from the Coalescence of a 2.5\text{-}4.5~M_\odot Compact Object and a Neutron Star

We report the observation of a coalescing compact binary with component masses 2.5\text{-}4.5~M_\odot and 1.2\text{-}2.0~M_\odot (all measurements quoted at the 90% credible level). The gravitational-wave signal GW230529_181500 was observed during the fourth observing run of the LIGO-Virgo-KAGRA detector network on 2023 May 29 by the LIGO Livingston Observatory. The primary... Show more