Large mass-ratio ($3< q \leq 10$) inspiral-merger-ringdown model for eccentric binary black holes

Abstract

We present $\texttt{EccHybIMR22}$, a fully analytical $\textbf{Ecc}$entric-$\textbf{Hyb}$rid-$\textbf{I}$nspiral-$\textbf{M}$erger-$\textbf{R}$ingdown model for the quadrupole ($\ell$=$2$, $|m|$=$2$ or simply the $\textbf{22}$) mode. The model is obtained by smoothly attaching an eccentric-inspiral to a quasi-circular-merger-ringdown prescription and is trained on eccentric numerical relativity (NR) simulations with mass ratios $q\leq 10$. In particular, we focus on obtaining a model that is sensitive to large mass ratios ($q>3$). Leveraging the recent expansion of SXS catalog of NR simulations, we construct a set of 91 hybrids (obtained by combining waveforms from post-Newtonian (PN) theory with NR simulations) with a target low total mass limit ($M_{\rm low}$) of $20M_{\odot}$ at an averaged 22 mode frequency of 20Hz, inaccessible with existing NR simulations alone. Employing a little less than a third of these hybrids as targets, we construct $\texttt{EccHybIMR22}$ and recover $65\%$ of the hybrids from the remaining set with mismatches smaller than $\sim3\%$ for a total mass of $40M_\odot$ (chosen arbitrarily) and orbital eccentricity $e_{\rm 20Hz}\lesssim0.33$ ($e_{\rm 20Hz}\lesssim 0.12$) for mass ratios $q\leq3$ ($q>3$). Furthermore, when tested against 175 SXS simulations, the model is able to recover nearly $80\%$ of the simulations with similar mismatches for systems with $0\lesssim e^{\rm NR}_{\rm 20Hz}\lesssim 0.3$.