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Second post-Newtonian radiative evolution of the relative orientations of angular momenta in spinning compact binaries

László Á. Gergely
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Abstract

The radiative evolution of the relative orientations of the spin and orbital angular momentum vectors ${\bf S}_{\bf 1}, {\bf S}_{\bf 2}$ and ${\bf L}$, characterizing a binary system on eccentric orbit is studied up to the second post-Newtonian order. As an intermediate result, all Burke-Thorne type instantaneous radiative changes in the spins are shown to average out over a radial period. It is proved that spin-orbit and spin-spin terms contribute to the radiative angular evolution equations, while Newtonian, first and second post-Newtonian terms together with the leading order tail terms do not. In complement to the spin-orbit contribution, given earlier, the spin-spin contribution is computed and split into two-body and self-interaction parts. The latter provide the second post-Newtonian order corrections to the 3/2 order Lense-Thirring description.

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László Á. Gergely. 2000-03-09. Second post-Newtonian radiative evolution of the relative orientations of angular momenta in spinning compact binaries. https://doi.org/10.1103/physrevd.62.024007

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