Gravitational-Wave Transient Event Catalog published along with the correspondent data

On August 26, 2025, while the fourth observing period (O4) of the LIGO, Virgo and KAGRA detectors was still in progress, version 4.0 of the Gravitational-Wave Transient Catalog (GWTC-4.0) was published. It contains the events detected during the first part of O4, between May 2023 and January 2024. This catalog extends our knowledge of binary black hole systems and mixed systems with a black hole and a neutron star.

Also published along with the catalog are all the data analyzed to produce it so that scientists outside the LIGO-Virgo-KAGRA collaboration can study it independently in the spirit of “open science.”