Cover Your Basis: Comprehensive Data-Driven Characterization of the Binary Black Hole Population

Understand

We introduce the first complete non-parametric model for the astrophysical distribution of the binary black hole (BBH) population.

• Constructed from basis splines, we use these models to conduct the most comprehensive data-driven investigation of the BBH population to date, simultaneously fitting non-parametric models for the BBH mass ratio, spin magnitude and misalignment, and redshift distributions.
• With GWTC-3, we report the same features previously recovered with similarly flexible models of the mass distribution, most notably the peaks in merger rates at primary masses of ${\sim}10\,M_\odot$ and ${\sim}35\,M_\odot$.
• Our model reports a suppressed merger rate at low primary masses and a mass ratio distribution consistent with a power law.