Constraints On The Dynamical Environments Of Supermassive Black-hole Binaries Using Pulsar-timing Arrays

Understand

We introduce a technique for gravitational-wave analysis, where Gaussian process regression is used to emulate the strain spectrum of a stochastic background using population-synthesis simulations.

• This leads to direct Bayesian inference on astrophysical parameters.
• For PTAs specifically, we interpolate over the parameter space of supermassive black-hole binary environments, including 3-body stellar scattering, and evolving orbital eccentricity.
• We illustrate our approach on mock data, and assess the prospects for inference with data similar to the NANOGrav 9-yr data release.