Prospects for Gravitational-Wave Observations of Neutron-Star Tidal Disruption in Neutron-Star–Black-Hole Binaries

For an inspiraling neutron-star–black-hole (NS-BH) binary, we estimate the gravity-wave frequency f_td at the onset of NS tidal disruption. We model the NS as a tidally distorted, homogeneous, Newtonian ellipsoid on a circular, equatorial geodesic around a Kerr BH. We find that f_td depends strongly on the NS radius R, and estimate that LIGO-II (ca. 2006–2008) might measure R to 15% precision at 140 Mpc ( ∼1 event/yr under current estimates). This suggests that LIGO-II might extract valuable information about the NS equation of state from tidal-disruption waves.