Adiabatic tides in compact binaries on quasielliptic orbits: Radiation at the second-and-a-half relative post-Newtonian order
Phys. Rev. D 114, 064062 – Published 16 September, 2026
DOI: https://doi.org/10.1103/bszd-247c
Abstract
We compute the gravitational fluxes and waveform for eccentric compact binaries including matter effects through adiabatic tidal interactions within the post-Newtonian approximation. The computations are performed at the relative 2.5PN order. Using the dynamics derived in Henry et al. (2025), we first derive the radiated energy and angular momentum, from which we deduce the equations describing the secular evolution of the orbital elements. We numerically solve for the secular dynamics for various systems. We find that the eccentric corrections to tidal terms induce a dephasing that could potentially be detectable in some regions of the parameter space of gravitational wave sources, especially for high enough initial eccentricity or mass ratio. Finally, we compute the amplitude of the strain, decomposed in spin-weighted spherical harmonics. Besides the memory contributions that are left for future works, we provide the amplitude modes containing the instantaneous, tail, and postadiabatic corrections expanded to the twelfth order in eccentricity. All relevant results are provided in the Supplemental Material. The expressions of the radiated fluxes and the secular evolution of orbital elements are valid for eccentricities up to 1, while the amplitude modes, due to the eccentricity expansion, are not valid beyond the Laplace limit .