With the recent release of the second gravitational-wave transient catalogue (GWTC-2), which introduced dozens of new detections, we are at a turning point of gravitational wave astronomy, as we are now able to directly infer constraints on the astrophysical population of compact objects. Here, we tackle the burning issue of understanding the origin of binary black hole (BBH) mergers. To this effect, we make use of state-of-the-art population synthesis and N-body simulations, to represent two distinct formation channels: BBHs formed in the field (isolated channel) and in young star clusters (dynamical channel). We then use a Bayesian hierarchical approach to infer the distribution of the mixing fraction $f$, with $f=0$ ($f=1$) in the pure dynamical (isolated) channel. %that controls the proportion of isolated and dynamical BBHs. We explore the effects of additional hyper-parameters of the model, such as the spread in metallicity $σ_{\text{Z}}$ and the parameter $σ_{\text{sp}}$, describing the distribution of spin magnitudes. We find that the dynamical model is slightly favoured with a median value of $f=0.26$, when $σ_{\text{sp}}=0.1$ and $σ_{\text{Z}}=0.4$. Models with higher spin magnitudes tend to strongly favour dynamically formed BBHs ($f\le{}0.1$ if $σ_{\text{sp}}=0.3$). Furthermore, we show that hyper-parameters controlling the rates of the model, such as $σ_{\rm Z}$, have a large impact on the inference of the mixing fraction, which rises from $0.18$ to $0.43$ when we increase $σ_{\text{Z}}$ from 0.2 to 0.6, for a fixed value of $σ_{\text{sp}}=0.1$. Finally, our current set of observations is better described by a combination of both formation channels, as a pure dynamical scenario is excluded at the $99\%$ credible interval, except when the spin magnitude is high.
Fast gravitational waveform models for quasi-circular coalescences of neutron star--black hole binaries
Universitat de les Illes Balears（巴利阿里群岛大学）；Max Planck Institute for Gravitational Physics (Albert Einstein Institute)（马克斯·普朗克引力物理研究所（爱因斯坦研究所））；Universität Potsdam（波茨坦大学）；CNRS/IN2P3, Laboratoire de Physique Corpusculaire (LPC) UMR6534（法国国家科学研究中心/法国国家核与粒子物理研究所，核物理实验室）；University of Canterbury（坎特伯雷大学）
Merger rate density of stellar-mass binary black holes from young massive clusters, open clusters, and isolated binaries: comparisons with LIGO-Virgo-KAGRA results
Evidence for additional structure in the effective spin distribution hints at multiple formation pathways in GWTC-5.0
LIGO Laboratory, Massachusetts Institute of Technology（麻省理工学院）；Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology（麻省理工学院卡弗里天体物理与空间研究所）；Department of Physics, Massachusetts Institute of Technology（麻省理工学院物理系）
Remnant recoil and host environments of GWTC-4.0 binary black-hole mergers
Universitat de les Illes Balears（巴利阿里群岛大学）；Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences（波兰科学院尼古拉·哥白尼天体物理中心）；University of Warsaw（华沙大学）；Max Planck Institute for Astrophysics（马克斯·普朗克天体物理学研究所）；Institut de Ciències de l’Espai (ICE, CSIC)（空间科学研究所（ICE，CSIC））
Optimizing Optical Searches for Supermassive Black Hole Binaries in AGN Light Curves: Fourier versus Bayesian Periodicity Detection
Vanderbilt University（范德堡大学）；Wake Forest University（维克森林大学）；Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA)（天体物理跨学科探索与研究中心）；Northwestern University（西北大学）
Evidence of the pair instability gap from black hole masses
Monash University（莫纳什大学）；OzGrav: The ARC Centre of Excellence for Gravitational Wave Discovery（OzGrav：引力波发现ARC卓越中心）；Canadian Institute for Theoretical Astrophysics, University of Toronto（多伦多大学加拿大理论天体物理研究所）；David A. Dunlap Department of Astronomy and Astrophysics, University of Toronto（多伦多大学大卫·A·邓普林天文学与天体物理学系）；Department of Physics, University of Toronto（多伦多大学物理系）；Nottingham Centre of Gravity & School of Mathematical Sciences, University of Nottingham（诺丁汉大学重力研究中心与数学科学学院）；LIGO Laboratory, Massachusetts Institute of Technology（麻省理工学院LIGO实验室）；Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology（麻省理工学院卡弗里天体物理学与空间研究研究所）；Department of Physics, Massachusetts Institute of Technology（麻省理工学院物理系）；Williams College（威廉姆斯学院）；Kavli Institute for Cosmological Physics, The University of Chicago（芝加哥大学卡弗里宇宙物理研究所）
Impact of eccentricity on the population properties of neutron star - black hole mergers
Max Planck Institute for Gravitational Physics (Albert Einstein Institute)（马克斯·普朗克引力物理研究所（爱因斯坦研究所））；Instituto de Física Teórica UAM/CSIC, Universidad Autónoma de Madrid（马德里自治大学理论物理研究所）；School of Physics and Astronomy and Institute for Gravitational Wave Astronomy, University of Birmingham（伯明翰大学物理与天文学学院及引力波天文研究所）
What do gravitational-wave observations tell us about Luminous Red Novae?
Aryabhatta Research Institute of Observational Sciences (ARIES)（阿亚巴塔观测科学研究所）；Department of Applied Physics, Mahatma Jyotibha Phule Rohilkhand University（马哈特玛·乔蒂巴·普勒罗希尔坎德大学应用物理系）；Inter-University Centre for Astronomy and Astrophysics（大学间天文学与天体物理学中心）；Institute for Gravitational Wave Astronomy and School of Physics and Astronomy, University of Birmingham（伯明翰大学引力波天文台及物理与天文学学院）；Bareilly College, Mahatma Jyotibha Phule Rohilkhand University（马哈特玛·乔蒂巴·普勒罗希尔坎德大学巴雷利学院）；Chennai Mathematical Institute（金奈数学研究所）
Can isolated binaries form unequal-mass binary black-hole mergers with a high-spin primary black hole?
Tsung-Dao Lee Institute, Shanghai Jiao-Tong University（李政道研究所，上海交通大学）；Center for Astrophysics and Planetary Science, Department of Astronomy, Cornell University（康奈尔大学天文学系天文与行星科学中心）；Institute for Astronomy, School of Physics, Zhejiang University（浙江大学物理学院天体物理研究所）；Center for Cosmology and Computational Astrophysics, Institute for Advanced Study in Physics, Zhejiang University（浙江大学物理高等研究院宇宙学与计算天体物理中心）
Joint constraints on the field-cluster mixing fraction, common envelope efficiency, and globular cluster radii from a population of binary hole mergers via deep learning
