Binary black holes (BBH) are expected to form and merge in active galactic nuclei (AGN), deep in the potential well of a supermassive black hole (SMBH), from populations that exist in a nuclear star cluster (NSC). Here we investigate the gravitational wave (GW) signature of a BBH lensed by a nearby SMBH. For a fiducial GW150914-like BBH orbiting close to a 108M⊙ SMBH located at z=0.1, the lensed GW signal varies in a predictable manner in and out of the LISA detectability band and across frequencies. The occurrence of such signatures has the potential to confound LISA global fit models if they are not modelled. Detection of these sources provide an independent measure of AGN inclination angles, along with detecting warping of the inner disk, and measuring the SMBH spin.
@article{arxiv.2502.10591,
title = {Evolution of LISA Observables for Binary Black Holes Lensed by an SMBH},
author = {Jake Postiglione and K. E. Saavik Ford and Henry Best and Barry McKernan and Matthew O'Dowd},
journal= {arXiv preprint arXiv:2502.10591},
year = {2025}
}