Self interaction of spins in binary systems

TL;DR

This paper calculates higher-order effects, including self-interaction of spins, on the gravitational wave evolution of binary systems with spins, quadrupoles, and magnetic moments, providing new insights into their coalescence behavior.

Contribution

It introduces the first detailed calculation of self-interaction spin terms at the second post-Newtonian order for spinning compact binaries.

Findings

Self-interaction spin terms are comparable to spin-spin effects in certain binaries.

The results are applicable to systems like the double pulsar J0737-3039.

Contributions significantly impact gravitational wave signal modeling.

Abstract

Beyond point mass effects various contributions add to the radiative evolution of compact binaries. We present all the terms up to the second post-Newtonian order contributing to the rate of increase of gravitational wave frequency and the number of gravitational wave cycles left until the final coalescence for binary systems with spin, mass quadrupole and magnetic dipole moments, moving on circular orbit. We evaluate these contributions for some famous or typical compact binaries and show that the terms representing the self interaction of individual spins, given for the first time here, are commensurable with the proper spin-spin contributions for the recently discovered double pulsar J0737-3039.