Comparing second-order gravitational self-force and effective one body waveforms from inspiralling, quasicircular and nonspinning black hole binaries. II. The large-mass-ratio case
Angelica Albertini, Alessandro Nagar, Adam Pound, Niels Warburton, Barry Wardell, Leanne Durkan, J. Miller
Abstract
We compare recently computed waveforms from second-order gravitational self-force (GSF) theory to those generated by a new, GSF-informed, effective one body (EOB) waveform model for (spin-aligned, eccentric) inspiralling black hole binaries with large mass ratios. We focus on quasicircular, nonspinning, configurations and perform detailed GSF/EOB waveform phasing comparisons, either in the time domain or via the gauge-invariant dimensionless function ${Q}_{\ensuremath{\omega}}\ensuremath{\equiv}{\ensuremath{\omega}}^{2}/\stackrel{\ifmmode \dot{}\else \textperiodcentered \fi{}}{\ensuremath{\omega}}$, where $\ensuremath{\omega}$ is the gravitational wave frequency. The inclusion of high-PN test-mass terms within the EOB radiation reaction (notably, up to 22PN) is crucial to achieve an EOB/GSF phasing agreement below 1 rad up to the end of the inspiral for mass ratios up to 500. For larger mass ratios, up to $5\ifmmode\times\else\texttimes\fi{}{10}^{4}$, the contribution of horizon absorption becomes more and more important and needs to be accurately modeled. Our results indicate that our GSF-informed EOB waveform model is a promising tool to describe waveforms generated by either intermediate or extreme mass ratio inspirals for future gravitational wave detectors.