Parameter estimation with the current generation of phenomenological waveform models applied to the black hole mergers of GWTC-1

TL;DR

This paper re-analyzes ten confirmed black hole merger gravitational-wave signals from GWTC-1 using advanced, efficient phenomenological waveform models to improve parameter estimation accuracy and validate previous results.

Contribution

It introduces the use of the latest IMRPhenomX and IMRPhenomT waveform models for detailed parameter estimation of GWTC-1 events, including precession and subdominant modes.

Findings

Results are consistent with original GWTC-1 analyses.

Including subdominant harmonics and precession affects posteriors.

Validation with multiple sampling codes confirms robustness.

Abstract

We consider the ten confidently detected gravitational-wave signals in the GWTC-1 catalog which are consistent with mergers of binary black hole systems, and perform a thorough parameter estimation re-analysis. This is made possible by using computationally efficient waveform models of the current (fourth) generation of the IMRPhenom family of phenomenological waveform models, which consists of the IMRPhenomX frequency-domain modelsand the IMRPhenomT time-domain models. The analysis is performed with both precessing and non-precessing waveform models with and without subdominant spherical harmonic modes. Results for all events are validated with convergence tests, discussing in particular the events GW170729 and GW151226. For the latter and the other two lowest-mass events, we also compare results between two independent sampling codes, Bilby and LALInference. We find overall consistent results with the original GWTC-1 results, with all Jensen-Shannon divergences between the previous results using IMRPhenomPv2 and our default IMRPhenomXPHM posteriors below 0.045 bits, but we also discuss cases where including subdominant harmonics and/or precession influences the posteriors.