Comparing eccentric waveform models based on post-Newtonian and effective-one-body approaches, over an observationally relevant parameter space

TL;DR

This study compares eccentric waveform models from post-Newtonian and effective-one-body approaches using extensive simulations across a broad parameter space to identify discrepancies and outliers in gravitational waveforms.

Contribution

It provides a comprehensive comparison of two numerical models for eccentric binary black hole waveforms over a large parameter space, highlighting differences and outliers.

Findings

Identified discrepancies in waveform mismatches between models.

Analyzed outlier points to understand model differences.

Performed extensive simulations covering diverse binary configurations.

Abstract

We used two numerical models, namely the \texttt{CBwaves} and \texttt{SEOBNRE} algorithms, based on the post-Newtonian and effective-one-body approaches for binary black holes evolving on eccentric orbits. We performed 20.000 new simulations for non-spinning and 240.000 simulations for aligned-spin configurations on a common grid of parameter values over the parameter space spanned by the mass ratio $q\equiv m_1/m_2\in[0.1,\,1]$, the gravitational mass $m_i \in [10M_\odot,\, 100M_\odot]$ of each component labeled by $i$, the corresponding spin magnitude $S_i \in [0,\,0.6]$ and a constant initial orbital eccentricity $e_{0}$. A detailed investigation was conducted to ascertain whether there was a discrepancy in the waveforms generated by the two codes. This involved an in-depth analysis of the mismatch. Furthermore, an extensive comparison was carried out on the outlier points between the two codes.