Numerical relativity reaching into post-Newtonian territory: a compact-object binary simulation spanning 350 gravitational-wave cycles

TL;DR

This paper presents a long-duration numerical relativity simulation of a compact-object binary that covers the entire frequency band of advanced gravitational-wave detectors, demonstrating the accuracy of effective-one-body models over post-Newtonian approximations.

Contribution

First long-duration numerical-relativity simulation of a binary covering the full detector frequency band, validating effective-one-body models against shorter waveforms.

Findings

Effective-one-body models match the new waveform well.

Post-Newtonian waveforms show significant disagreement.

Modeling errors have negligible impact on detection rates.

Abstract

We present the first numerical-relativity simulation of a compact-object binary whose gravitational waveform is long enough to cover the entire frequency band of advanced gravitational-wave detectors, such as LIGO, Virgo and KAGRA, for mass ratio 7 and total mass as low as $45.5\,M_\odot$. We find that effective-one-body models, either uncalibrated or calibrated against substantially shorter numerical-relativity waveforms at smaller mass ratios, reproduce our new waveform remarkably well, with a negligible loss in detection rate due to modeling error. In contrast, post-Newtonian inspiral waveforms and existing calibrated phenomenological inspiral-merger-ringdown waveforms display greater disagreement with our new simulation. The disagreement varies substantially depending on the specific post-Newtonian approximant used.