Revealing phase transition in dense matter with gravitational wave spectroscopy of binary neutron star mergers

We use numerical relativity simulations of binary neutron star mergers to show that high density deconfinement phase transitions to quark matter can be probed using multimodal postmerger gravitational wave (GW) spectroscopy. Our simulations suggest that hadron-quark phase transitions may suppress the one-armed spiral instability in the remnant. This is manifested in an anticorrelation between the energy carried in the ℓ=2, m=1 GW mode and energy density gap which separates the two phases. Our work demonstrates a potential connection between features of the postmerger GW spectrum and microphysical features of the high-density equation of state.