A first survey of spinning eccentric black hole mergers: Numerical relativity simulations, hybrid waveforms, and parameter estimation

TL;DR

This paper presents a comprehensive analysis of spinning eccentric black hole mergers using numerical relativity, hybrid waveforms, and Bayesian parameter estimation, highlighting the impact of eccentricity and spin on waveform modeling and parameter biases.

Contribution

It introduces new eccentric hybrid waveforms for spinning black hole binaries and evaluates the biases in parameter estimation when using quasicircular models for eccentric systems.

Findings

Eccentric hybrid waveforms connect numerical relativity data with post-Newtonian models.

Aligned-spin quasicircular models with higher modes reduce parameter biases.

Eccentricity and spin significantly affect waveform accuracy and parameter estimation.

Abstract

We analyze a new numerical relativity dataset of spinning but nonprecessing binary black holes on eccentric orbits, with eccentricities from approximately $0.1$ to $0.5$, with dimensionless spins up to $0.75$ included at mass ratios $q=m_1/m_2 = (1, 2)$, and further nonspinning binaries at mass ratios $q = (1.5, 3, 4)$. A comparison of the final mass and spin of these simulations with noneccentric data extends previous results in the literature on circularization of eccentric binaries to the spinning case. For the $(l,m)=(2,2)$ spin-weighted spherical harmonic mode we construct eccentric hybrid waveforms that connect the numerical relativity data to a post-Newtonian description for the inspiral, and we discuss the limitations in the current knowledge about post-Newtonian theory which complicate the generation of eccentric hybrid waveforms. We also perform a Bayesian parameter estimation study, quantifying the parameter biases introduced when using three different quasicircular waveform models to estimate the parameters of highly eccentric binary systems. We find that the used aligned-spin quasicircular model including higher order modes produces lower bias in certain parameters than the nonprecessing quasicircular model without higher order modes and the quasicircular precessing model.