2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/230386The radial component of the motion of compact binary systems composed of neutron stars and/or black holes on eccentric orbit is integrated. We consider all type of perturbations that emerge up to second post-Newtonian order. These perturbations are either of relativistic origin or are related to the spin, mass quadrupole and magnetic dipole moments of the binary components. We derive a generalized Kepler equation and investigate its domain of validity, in which it properly describes the radial motion.to appear in the Proceedings of the Eleventh Marcel Grossmann Meeting 2006, World Scientific, Singapore (2007)General Relativity and Quantum CosmologyAstrophysicstext