Dissipative tidal effects to next-to-leading order and constraints on the dissipative tidal deformability using gravitational wave data

Dissipative tidal interactions can be used to probe the out-of-equilibrium physics of neutron stars using gravitational wave observations. In this paper, we present the first post-Newtonian (PN) corrections to the orbital dynamics of a binary system containing objects whose tidal interactions have a dissipative contribution. We derive the 1 PN-accurate equations of motion in the center-of-mass frame and a generalized energy-balance law that is valid for dissipative tidal interactions. We show how mass and energy loss due to the absorption of orbital energy change the orbital dynamics and derive the next-to-leading order correction to the gravitational wave phase of a binary system in a quasicircular orbit containing initially nonspinning components. We then use this waveform model to constrain, for the first time, the individual dissipative tidal deformabilities of each of the binary components that generated the GW170817 event using real data. We find that the GW170817 data require Ξ₁1121 and Ξ₂1692 at 90% confidence, where Ξ1,2 are the individual tidal deformabilities of the primary and secondary binary components that produced the GW170817 event.