Parameter estimation of gravitational waves from hyperbolic black hole encounters

TL;DR

This paper adapts the RIFT parameter estimation algorithm to analyze gravitational wave signals from hyperbolic black hole encounters, including scattering and plunge events, using the TEOBResumSDALI waveform model.

Contribution

It introduces a method to accurately estimate parameters of hyperbolic black hole encounters, expanding gravitational wave analysis beyond traditional inspiral signals.

Findings

RIFT accurately recovers mass, spins, and orbit parameters

Method works with simulated signals at Cosmic Explorer sensitivity

Demonstrates feasibility for unbound black hole encounters

Abstract

Systems of two black holes with unbound orbits can produce a diverse array of gravitational wave signals with rich morphology. This parameter space encompasses both hyperbolic orbit scattering events and dynamical captures, including zoom-whirl orbits with multiple flybys and direct plunge mergers. These signals challenge traditional parameter estimation infrastructure, which is largely optimized for quasicircular inspiral binaries. In this work we discuss the adaptation of the Rapid Iterative FiTting (RIFT) algorithm to this problem using the TEOBResumSDALI waveform model which can simulate generic orbits. We present results from a study of simulated signals emulating a scatter and plunge event, utilizing the design sensitivity of the forthcoming Cosmic Explorer interferometer. Our analysis demonstrates that RIFT accurately recovers the mass, spins, and hyperbolic orbit parameters: the system energy and angular momentum defined at a fiducial initial separation.