Spin-perturbed orbits near black holes

Abstract

Inspirals of rotating stellar-mass compact objects into massive black holes are influenced by the spin-curvature coupling, which drives the compact body away from geodesic motion due to its rotation. I formulate the Hamilton-Jacobi equation for a spinning test body orbiting a Kerr black hole, solve it to linear order in spin, and use the perturbative solution to compute the fundamental frequencies of motion along the orbit. This result provides one of the necessary ingredients for waveform models for the upcoming space-based gravitational-wave detector LISA.