Gravitational spin-orbit coupling in binary systems at the second post-Minkowskian approximation

TL;DR

This paper calculates the spin rotations during scattering events of two gravitationally interacting particles at second post-Minkowskian order, enhancing the Effective One-Body model for spinning binary systems.

Contribution

It provides an improved computation of spin-orbit interactions at second post-Minkowskian order and integrates these into the EOB framework for better modeling of spinning binary black holes.

Findings

Derived spin rotation results at second PM order.

Enhanced the spin-orbit sector of the EOB Hamiltonian.

Proposed resummation methods for improved EOB models.

Abstract

We compute the rotations, during a scattering encounter, of the spins of two gravitationally interacting particles at second-order in the gravitational constant (second post-Minkowskian order). Following a strategy introduced in Phys. Rev. D {\bf 96}, 104038 (2017), we transcribe our result into a correspondingly improved knowledge of the spin-orbit sector of the Effective One-Body (EOB) Hamiltonian description of the dynamics of spinning binary systems. We indicate ways of resumming our results for defining improved versions of spinning EOB codes which might help in providing a better analytical description of the dynamics of coalescing spinning binary black holes.