Fast gravitational waveform models for quasicircular coalescences of neutron star-black hole binaries
Phys. Rev. D 114, 064044 – Published 9 September, 2026
DOI: https://doi.org/10.1103/b3c9-s8lh
Abstract
We present imrphenomxhm_nsbh and seobnrv5hm_rom_nrtidalv3_nsbh, the first two frequency-domain models for gravitational-wave signals from quasicircular, aligned-spin neutron star-black hole binaries including higher-order modes beyond the dominant quadrupole. We also present imrphenomxphm_nsbh, an extension of the former model to the spin-precessing case. These models incorporate tidal effects in the gravitational-wave phasing and amplitude using a higher-mode extension of the NRTidalv3 model as well as dedicated amplitude models calibrated to numerical-relativity simulations of neutron star-black hole mergers. We test the performance and validity of the new models by comparing them to numerical-relativity simulations and other existing models for these systems. Finally, we perform parameter estimation studies. The new models show clear improvements over their predecessors in analyses of simulated signals while yielding results consistent with the literature when applied to real events from the GWTC-3 and GWTC-4 catalogs.
