Systematic biases in parameter estimation of binary black-hole mergers

TL;DR

This study assesses the systematic biases in estimating binary black hole parameters using current waveform models, finding biases are small for ground-based detectors but more significant at higher SNRs and in space-based observations.

Contribution

It provides a detailed analysis of the magnitude of systematic biases in parameter estimation with effective-one-body templates across different detector sensitivities.

Findings

Biases are within statistical errors for realistic ground-based SNRs.

Biases become comparable to statistical errors at high ground-based SNRs (50).

Biases remain small (a few percent) for black hole mass estimates in space-based detectors.

Abstract

Parameter estimation of binary-black-hole merger events in gravitational-wave data relies on matched-filtering techniques, which, in turn, depend on accurate model waveforms. Here we characterize the systematic biases introduced in measuring astrophysical parameters of binary black holes by applying the currently most accurate effective-one-body templates to simulated data containing non-spinning numerical-relativity waveforms. For advanced ground-based detectors, we find that the systematic biases are well within the statistical error for realistic signal-to-noise ratio (SNR). These biases grow to be comparable to the statistical errors at high ground-based-instrument SNRs (SNR=50), but never dominate the error budget. At the much larger signal-to-noise ratios expected for space-based detectors, these biases will become large compared to the statistical errors, but for astrophysical black hole mass estimates the absolute biases (of at most a few percent) are still fairly small.