## [1312.0775] Gravitational Self-Torque and Spin Precession in Compact Binaries

Authors: Sam R. Dolan, Niels Warburton, Abraham I. Harte, Alexandre Le Tiec, Barry Wardell, Leor Barack

Date: 3 Dec 2013

Abstract: We calculate the effect of self-interaction on the "geodetic" spin precession of a compact body in a strong-field orbit around a black hole. Specifically, we consider the spin precession angle $\psi$ per radian of orbital revolution for a particle carrying mass $\mu$ and spin $s \ll (G/c) \muˆ2$ in a circular orbit around a Schwarzschild black hole of mass $M \gg \mu$. We compute $\psi$ through $O(\mu/M)$ in perturbation theory, i.e, including the correction $\delta\psi$ (obtained numerically) due to the torque exerted by the conservative piece of the gravitational self-field. Comparison with a post-Newtonian (PN) expression for $\delta\psi$, derived here through 3PN order, shows good agreement but also reveals strong-field features which are not captured by the latter approximation. Our results can inform semi-analytical models of the strong-field dynamics in astrophysical binaries, important for ongoing and future gravitational-wave searches.

#### Dec 03, 2013

1312.0775 (/preprints)
2013-12-03, 21:30