Black Hole-Neutron Star mergers in the parameter range of GW170817

We present simulations of low-mass black hole-neutron star (BHNS) mergers performed with the SpEC code. Black holes of less than two solar masses have never been observed, but cannot at this point be ruled out. The observation of a gravitational wave (GW) signal from a BHNS binary with such a low mass black hole would nearly certainly be mistaken for a binary neutron star (BNS) mergers. We use our simulations to study mass ejection and disk formation in low-mass BHNS mergers, and extract information regarding the observable properties of these systems. We also use our results to show that, even though the observed GW170817 event was most likely a BNS merger, a wide range of BHNS binary parameters remain compatible with both the GW signal and the bolometric kilonova light curve.