Speaker
Description
We present IMRPhenomXHM_NSBH, a new phenomenological model for graviational-wave (GW) emission from neutron star–black hole (NSBH) coalescences. This model features a newly developed numerical relativity (NR)-calibrated amplitude prescription incorporating tidal contributions up to 7.5PN order, a phasing model tuned to NR simulations incorporating dynamical tidal effects (NRTidalv3), and the inclusion of higher GW strain harmonics also including tidal corrections calibrated to numerical relativity.
This model represents a significant improvement over previous phenomenological GW models for NSBHs, providing smooth and well-behaved waveforms across the parameter space with enhanced physical fidelity while introducing minimal computational overhead compared to its baseline binary black hole model, IMRPhenomXHM. As a result, it is the fastest NSBH model including higher-order harmonics, with its (2,2) mode being roughly an order of magnitude faster than previous NSBH models for this mode.
Finally, we discuss the prospects of extending the model to incorporate spin-precession and orbital eccentricity effects.
