Constraining binaries of black hole mimickers using gravitational waves

There are various theoretical proposals for objects that are massive and compact enough to be mistaken for black holes observationally, e.g., boson stars. Binaries of such objects can be distinguished from binaries of black holes using gravitational wave (GW) observations. In particular, the inspiral signal from a binary of black hole mimickers has imprints of the objects' nonzero tidal deformabilities and non-black hole spin-induced multipole moments. Thus, one can use constraints on these effects to constrain properties of black hole mimickers that could produce GW signals identified as coming from binary black holes (BBHs). However, one has to exclude the less well-modeled post-inspiral signal from this analysis. We show that one can recover the true parameters of black hole mimicker-like signals by self-consistently restricting to the low-frequency portion of the signal. Here we perform the analysis using an extension of the IMRPhenomXP precessing BBH waveform model with additions in the phase of post-Newtonian tidal and spin-induced multipole terms, including the fmtidal model for dynamical tides. We use TEOBResumS + numerical relativity hybrid binary neutron star waveforms scaled to BBH-like masses to test the analysis.