O4a Open Data Release

First published: August 24, 2025

The LIGO, Virgo, and KAGRA collaborations have publicly released a new dataset from the first segment of their fourth observing run (O4a) covering Gravitational-Wave (GW) observations from May 24, 2023, to January 16, 2024.

The data release currently includes strain data from the two LIGO observatories and also some of their auxiliary channels. The users will also find in our pages the fourth version of the Gravitational Wave Transient Catalog (GWTC 4.0).