GWTC-4.0: Updating the Gravitational-wave Transient Catalog with Observations from the First Part of the Fourth LIGO–Virgo–KAGRA Observing Run

Authors

• A. G. Abac
• I. Abouelfettouh
• Teviet Creighton, The University of Texas Rio Grande ValleyFollow
• Mario C. Diaz, The University of Texas Rio Grande ValleyFollow
• Raul Alberto Espinosa Perez, The University of Texas Rio Grande Valley
• J. Lawrence, The University of Texas Rio Grande Valley
• Francisco Llamas Villarreal, The University of Texas Rio Grande Valley
• Soma Mukherjee, The University of Texas Rio Grande ValleyFollow
• Volker Quetschke, The University of Texas Rio Grande ValleyFollow
• Miriam Ramos Arevalo, The University of Texas Rio Grande ValleyFollow
• Wenhui Wang, The University of Texas Rio Grande Valley

Document Type

Article

Publication Date

6-20-2026

Abstract

Version 4.0 of the Gravitational-Wave Transient Catalog (GWTC-4.0) adds new candidates detected by the LIGO, Virgo, and KAGRA observatories through the first part of the fourth observing run (O4a: 2023 May 24 15:00:00 to 2024 January 16 16:00:00 UTC) and a preceding engineering run. In these new data, we find 128 compact binary coalescence candidates that are identified by at least one of our search algorithms with a probability of astrophysical origin pastro ≥ 0.5 and that are not vetoed during event validation. We also provide detailed source property measurements for 86 of these that have a false-alarm rate < 1 yr−1. Based on the inferred component masses, these candidates are consistent with signals from binary black holes (BBHs) and neutron star–black hole binaries (GW230518_125908 and GW230529_181500). Median-inferred component masses of BBHs in the catalog now range from 5.79M⊙ (GW230627_015337) to 137 (GW231123_135430), while GW231123_135430 was probably produced by the most massive binary observed in the catalog. For the first time, we have discovered BBH signals with network signal-to-noise ratio exceeding 30, GW230814_230901 and GW231226_101520, enabling high-fidelity studies of the waveforms and astrophysical properties of these systems. Combined with the 90 candidates included in GWTC-3.0, the catalog now contains 218 candidates with pastro ≥ 0.5 and not otherwise vetoed, more than doubling the size of the catalog and further opening our view of the gravitational-wave Universe.

Comments

Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

Recommended Citation

Abac, A. G., I. Abouelfettouh, F. Acernese, et al. “GWTC-4.0: Updating the Gravitational-Wave Transient Catalog with Observations from the First Part of the Fourth LIGO–Virgo–KAGRA Observing Run.” The Astrophysical Journal Letters 1004, no. 2 (2026): L22. https://doi.org/10.3847/2041-8213/ae2c74.

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

Publication Title

The Astrophysical Journal Letters

DOI

10.3847/2041-8213/ae2c74