Determine accuracy requirements for NR simulations and waveform models in GW astronomy

Determine quantitative accuracy requirements for numerical relativity simulations and gravitational waveform models that are sufficient to ensure reliable gravitational-wave parameter estimation and avoid significant biases in measurements across relevant signal-to-noise ratios and binary configurations.

Background

The paper presents new numerical relativity simulations of highly precessing, high–mass-ratio (q=18) binary black holes and demonstrates that state-of-the-art waveform models exhibit large mismatches and parameter biases in this regime. While mismatch errors in the NR waveforms can be non-negligible, the authors find that these errors often project largely orthogonal to the physical parameter manifold, complicating the mapping between waveform accuracy and parameter estimation performance.

These observations highlight that there is currently no robust, generally applicable criterion linking NR or model mismatch to acceptable parameter biases for gravitational-wave observations. Consequently, establishing clear, quantitative accuracy thresholds for both NR simulations and waveform models remains unresolved and is essential for future detectors and analyses.

References

The full determination of NR and waveform accuracy requirements remains an open question.

— The High-Mass-Ratio Challenge in Gravitational Waveform Modelling  (2603.26521 - Mahapatra et al., 27 Mar 2026) in Section 6 (Discussion)

The impact of waveform mismodeling---such as neglected eccentricity---on these joint analyses has not yet been quantified; we will address it in upcoming work through a joint eccentric, spin-precessing analysis of the signal and glitch.

— Enabling gravitational-wave astronomy with spin-precessing black holes on generic orbits  (2609.01568 - Gamboa et al., 1 Sep 2026) in Supplemental Material, Additional details of the GW200129 analysis (Section label sm:gw200129)