GWTC-4.0: Population Properties of Merging Compact Binaries
40 affiliations
- 1Max Planck Institute for Gravitational Physics (Albert Einstein Institute)
- 2LIGO Hanford Observatory
- 3INFN
- 4Università di Salerno
- 5University of Warwick
- 6Monash University
- 7The Pennsylvania State University
- 8Leibniz Universität Hannover
- 9University of Wisconsin-Milwaukee
- 10California Institute of Technology
- 11Louisiana State University
- 12Tata Institute of Fundamental Research
- 13Inter-University Centre for Astronomy and Astrophysics
- 14Université Catholique de Louvain
- 15Queen Mary University of London
- 16Sejong University
- 17Instituto Nacional de Pesquisas Espaciais
- 18University of the West of Scotland
- 19Università di Roma Tor Vergata
- 20Universiteit Antwerpen
- 21Advanced Technology Center
- 22Gravitational Wave Science Project
- 23Friedrich-Schiller-Universität Jena
- 24INFN Sezione di Torino
- 25University of Glasgow
- 26University of Western Australia
- 27Université Savoie Mont Blanc
- 28Università di Napoli “Federico II”
- 29Cardiff University
- 30Australian National University
- 31Massachusetts Institute of Technology
- 32Maastricht University
- 33Nikhef
- 34Aix Marseille Univ
- 35Université Paris-Saclay
- 36The University of Tokyo
- 37University of Tokyo
- 38Universitat de Barcelona (UB)
- 39The Barcelona Institute of Science and Technology
- 40Gran Sasso Science Institute (GSSI)
Abstract
We detail the population properties of binary neutron star, neutron star–black hole binary, and binary black hole mergers using 158 events from the cumulative Gravitational-Wave Transient Catalog 4.0. The black hole primary mass distribution consists of a power-law-like continuum that steepens above 35 M ⊙ with overdensities at 10 M ⊙ and 35 M ⊙ . Binary black holes with primary masses near 10 M ⊙ are more likely to have less massive secondaries, with a mass ratio distribution peaking at q = 0.7 1 − 0.11 + 0.12 , potentially a signature of stable mass transfer during binary evolution. Black hole spins are inferred to be nonextremal, with 90% of black holes having χ < 0.6, and preferentially aligned with binary orbits, implying many merging binaries form in isolation. However, we find that a significant fraction, 0.23–0.41, of binaries have negative effective inspiral spins, suggesting many could be formed dynamically in gas-free environments. We find evidence for correlation between effective inspiral spin and mass ratio, driven either by variation in the mode of the distribution or the width. The binary black hole merger rate increases with redshift, consistent with the cosmic star formation density. While there is no evidence of the mass spectrum evolving with redshift, the distribution of effective inspiral spin is found to broaden as redshift increases out to z ≈ 1. We infer the local merger rates (at z = 0) to be 8.8–250 Gpc −3 yr −1 for binary neutron stars, 9.3–86 Gpc −3 yr −1 for neutron star–black hole binaries, and 13–26 Gpc −3 yr −1 for binary black holes; all values reflect central 90% credible intervals.
Related
- GWTC-5.0: Population Properties of Merging Compact Binaries
- Natal Kicks of Compact Binaries: I. Population Synthesis Framework and Illustrative Examples
- Eccentricity and Inclination Excitation of Stellar Orbits around merging Black-Hole Binaries
- Eccentricity and Inclination Excitation of Stellar Orbits around Merging Black Hole Binaries
- Formation of Merging Black Hole Binaries Inside Massive AGN Stars
BibTeX
@article{abac2026gwtc40,
title = {{GWTC-4.0: Population Properties of Merging Compact Binaries}},
author = {Adrian Abac and I. Abouelfettouh and F. Acernese and K. Ackley and Christian Adamcewicz and S. Adhicary and D. Adhikari and N. Adhikari and R. X. Adhikari and V. K. Adkins and Samsuzzaman Afroz and D. Agarwal and M. Agathos and Maryam Aghaei Abchouyeh and Odylio D. Aguiar and S. Ahmadzadeh and L. Aiello and A. Ain and P. Ajith and Tomotada Akutsu and Simone Albanesi and R. A. Alfaidi and Ammar Al-Jodah and C. Alléné and A. Allocca and S. Al-Shammari and P. A. Altin and S. Álvarez-López and O. Amarasinghe and A. Amato and Claude Amra and A. Ananyeva and S. B. Anderson and Warren G. Anderson and M. Andia and M. Ando and T Andrade and Marc Andrés-Carcasona and T. Andrić and J. Anglin and Stefano Ansoldi and Javier Mauricio Antelis and S. Antier and M. Aoumi and E. Z. Appavuravther and S. Appert and S. K. Apple and Koji Arai and A. Araya and M. C. Araya and Manuel Arca Sedda and J. S. Areeda and L Argianas and N. Aritomi and F. Armato and Sharon Armstrong and N. Arnaud and M. Arogeti and Scott Aronson and K. G. Arun},
journal = {The Astrophysical Journal Letters},
year = {2026},
month = jul,
doi = {10.3847/2041-8213/ae771e},
url = {https://doi.org/10.3847/2041-8213/ae771e},
note = {CC BY},
}
RIS
TY - JOUR
TI - GWTC-4.0: Population Properties of Merging Compact Binaries
AU - Adrian Abac
AU - I. Abouelfettouh
AU - F. Acernese
AU - K. Ackley
AU - Christian Adamcewicz
AU - S. Adhicary
AU - D. Adhikari
AU - N. Adhikari
AU - R. X. Adhikari
AU - V. K. Adkins
AU - Samsuzzaman Afroz
AU - D. Agarwal
AU - M. Agathos
AU - Maryam Aghaei Abchouyeh
AU - Odylio D. Aguiar
AU - S. Ahmadzadeh
AU - L. Aiello
AU - A. Ain
AU - P. Ajith
AU - Tomotada Akutsu
AU - Simone Albanesi
AU - R. A. Alfaidi
AU - Ammar Al-Jodah
AU - C. Alléné
AU - A. Allocca
AU - S. Al-Shammari
AU - P. A. Altin
AU - S. Álvarez-López
AU - O. Amarasinghe
AU - A. Amato
AU - Claude Amra
AU - A. Ananyeva
AU - S. B. Anderson
AU - Warren G. Anderson
AU - M. Andia
AU - M. Ando
AU - T Andrade
AU - Marc Andrés-Carcasona
AU - T. Andrić
AU - J. Anglin
AU - Stefano Ansoldi
AU - Javier Mauricio Antelis
AU - S. Antier
AU - M. Aoumi
AU - E. Z. Appavuravther
AU - S. Appert
AU - S. K. Apple
AU - Koji Arai
AU - A. Araya
AU - M. C. Araya
AU - Manuel Arca Sedda
AU - J. S. Areeda
AU - L Argianas
AU - N. Aritomi
AU - F. Armato
AU - Sharon Armstrong
AU - N. Arnaud
AU - M. Arogeti
AU - Scott Aronson
AU - K. G. Arun
PY - 2026
DA - 2026/07/03
JO - The Astrophysical Journal Letters
DO - 10.3847/2041-8213/ae771e
UR - https://doi.org/10.3847/2041-8213/ae771e
AB - We detail the population properties of binary neutron star, neutron star–black hole binary, and binary black hole mergers using 158 events from the cumulative Gravitational-Wave Transient Catalog 4.0. The black hole primary mass distribution consists of a power-law-like continuum that steepens above 35 M ⊙ with overdensities at 10 M ⊙ and 35 M ⊙ . Binary black holes with primary masses near 10 M ⊙ are more likely to have less massive secondaries, with a mass ratio distribution peaking at q = 0.7 1 − 0.11 + 0.12 , potentially a signature of stable mass transfer during binary evolution. Black hole spins are inferred to be nonextremal, with 90% of black holes having χ < 0.6, and preferentially aligned with binary orbits, implying many merging binaries form in isolation. However, we find that a significant fraction, 0.23–0.41, of binaries have negative effective inspiral spins, suggesting many could be formed dynamically in gas-free environments. We find evidence for correlation between effective inspiral spin and mass ratio, driven either by variation in the mode of the distribution or the width. The binary black hole merger rate increases with redshift, consistent with the cosmic star formation density. While there is no evidence of the mass spectrum evolving with redshift, the distribution of effective inspiral spin is found to broaden as redshift increases out to z ≈ 1. We infer the local merger rates (at z = 0) to be 8.8–250 Gpc −3 yr −1 for binary neutron stars, 9.3–86 Gpc −3 yr −1 for neutron star–black hole binaries, and 13–26 Gpc −3 yr −1 for binary black holes; all values reflect central 90% credible intervals.
SN - 2041-8205
SN - 2041-8213
ER -