Work

Inferring the pair-instability mass gap from gravitational wave data

Year: 2025

Type: article

Abstract: We use hierarchical Bayesian inference with nonparametric Gaussian process models to investigate the effective inspiral spin parameter, χ eff , as a function of primary black hole mass in the third gravitational-wave transient catalog (GWTC-3). Our analysis reveals a transition in the population at a primary mass of 46 − 5 + 7 M ⊙ . Beyond this mass, the χ eff distribution broadens, becomes consistent with being symmetric around zero, and has a median of − 0.0 3 − 0.59 + 0.36 (90% credibility). These results are consistent with the presence of a pair-instability mass gap that is repopulated by black holes that are the remnant of a previous merger, formed in dense star clusters. However, asymmetric distributions skewed toward positive χ eff are not excluded by current data. Below the inferred transition mass, we constrain the fraction of second-generation black holes to be ≲ 10 % . These results provide model-independent support for a high-mass and high-spin population of black holes in the data, consistent with earlier work using parametric models. Imminent gravitational-wave data releases will be essential to sharpen constraints on spin symmetry and clarify the origin of the black holes.

Source: Physical review. D/Physical review. D.

DOI: 10.1103/nxnr-pdyx

Authors: Fabio Antonini, Thomas Callister, Fani Dosopoulou, Isobel M. Romero-Shaw, Debatri Chattopadhyay

Institutions: Cardiff University, University of Chicago, University of Cambridge, Northwestern University

Language: English

Topic: Pulsars and Gravitational Waves Research

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid