Periastron advance in neutron star-black hole binaries

As neutron star-black hole binaries are expected to be discovered through future pulsar surveys using upcoming facilities, it is necessary to understand various observable properties of such systems. In this work, we study the advance of the periastron of such binaries under the post-Newtonian formalism over a wide range of parameters. We find that the first-and second-order post-Newtonian effects and the leading order spin-orbit coupling effects are significant for such binaries but higher order effects can be neglected.