Image Details
GWTC-4.0: Population Properties of Merging Compact Binaries
A. G. Abac et al 2026 The Astrophysical Journal Letters 1005 .
Caption: Figure 7.
Marginal spin magnitude χ (left) and cosine tilt angle ﹩\cos \theta ﹩ (right) distributions under the GAUSSIAN COMPONENT SPINS (blue) and B-SPLINE (green) models. The results from the GWTC-3.0 DEFAULT are shown for comparison (black dashed); note that this model is different from what is used for GWTC-4.0. The GWTC-3.0 analysis employed a Beta distribution for spin magnitudes rather than a truncated normal and fixed the location of the Gaussian component of the spin tilt angle distribution to ﹩\cos \theta =1﹩ rather than letting it vary freely in inference. The solid lines show the median of the inferred distributions from GWTC-4.0, and the shaded regions show their 90% credible regions. The thick dashed lines show the median from GWTC-3.0, while the thin dashed lines show its 90% credible region.
© 2026. The Author(s). Published by the American Astronomical Society.