Dissecting Gravitational-waves from Heavy Binary Black Holes in the Time Domain*

Lying on the edge of the Laser Interferometer Gravitational-wave Observatory's (LIGO) sensitivity, the short-duration observable gravitational-wave signals from highly massive binary black holes are dominated by the merger phase of coalescence where the imprint of many physical effects remains poorly understood. In Miller et. al. 2024, we conduct parameter estimation in the time domain to trace the effect of spin precession cycle-by-cycle on the heaviest binary black hole confidently detected by LIGO to date, GW19051, finding that the inference of precession stems in the signal from the suppression of a weak portion of the pre-merger data with respect to the louder merger-ringdown. Here, we expand upon this framework and explore the utility of time-domain inference to locate the imprint of different underlying physical effects (e.g. spin precession, mass ratio, and eccentricity) on simulated merger-dominated waveforms. Establishing a consistent picture between a binary black hole's source dynamics and the resulting observed data is crucial for characterizing the growing number of LIGO observations, safeguarding against data quality issues and systematics, and ensuring the robustness of resultant astrophysical claims.