Tail-induced spin-orbit effect in the gravitational radiation of compact binaries
Luc Blanchet, Alessandra Buonanno, Guillaume Faye
TL;DR
This work advances analytical gravitational-wave modeling for spinning compact binaries by deriving spin-orbit tail effects at $3$PN in the energy flux and at $2.5$PN/$3$PN in the waveform, thereby yielding accurate $3$PN phasing corrections for quasi-circular inspirals. The authors integrate tail integrals within the multipolar post-Newtonian framework, account for spin precession through a moving triad, and verify consistency with the test-particle limit against black-hole perturbation theory. The results enhance template fidelity for parameter estimation and NR comparisons, supporting improved predictions through the inspiral and merger phases. Future directions include completing non-tail SO couplings at $2$PN/$3$PN orders and extending computations to higher gravitational modes to further refine analytical templates.
Abstract
Gravitational waves contain tail effects which are due to the back-scattering of linear waves in the curved space-time geometry around the source. In this paper we improve the knowledge and accuracy of the two-body inspiraling post-Newtonian (PN) dynamics and gravitational-wave signal by computing the spin-orbit terms induced by tail effects. Notably, we derive those terms at 3PN order in the gravitational-wave energy flux, and 2.5PN and 3PN orders in the wave polarizations. This is then used to derive the spin-orbit tail effects in the phasing through 3PN order. Our results can be employed to carry out more accurate comparisons with numerical-relativity simulations and to improve the accuracy of analytical templates aimed at describing the whole process of inspiral, merger and ringdown.
