The Samurai Project: verifying the consistency of black-hole-binary waveforms for gravitational-wave detection

TL;DR

This paper assesses the consistency of numerical relativity black-hole-binary waveforms across different codes, demonstrating their high agreement and suitability for gravitational-wave detection in current and future observatories.

Contribution

It provides a detailed comparison of waveforms from five numerical codes, establishing their agreement and validating their use in gravitational-wave searches.

Findings

Waveform phase and amplitude agree within uncertainties.

Mismatch is below 10^{-3} for certain mass ranges.

Waveforms are indistinguishable at typical detection SNRs.

Abstract

We quantify the consistency of numerical-relativity black-hole-binary waveforms for use in gravitational-wave (GW) searches with current and planned ground-based detectors. We compare previously published results for the $(\ell=2,| m | =2)$ mode of the gravitational waves from an equal-mass nonspinning binary, calculated by five numerical codes. We focus on the 1000M (about six orbits, or 12 GW cycles) before the peak of the GW amplitude and the subsequent ringdown. We find that the phase and amplitude agree within each code's uncertainty estimates. The mismatch between the $(\ell=2,| m| =2)$ modes is better than $10^{-3}$ for binary masses above $60 M_{\odot}$ with respect to the Enhanced LIGO detector noise curve, and for masses above $180 M_{\odot}$ with respect to Advanced LIGO, Virgo and Advanced Virgo. Between the waveforms with the best agreement, the mismatch is below $2 \times 10^{-4}$. We find that the waveforms would be indistinguishable in all ground-based detectors (and for the masses we consider) if detected with a signal-to-noise ratio of less than $\approx14$, or less than $\approx25$ in the best cases.