  We have modelled the spatial distribution of luminous X-ray binaries (XRBs)
in spiral galaxies that are like the Milky Way using an evolutionary population
synthesis code. In agreement with previous theoretical expectations and
observations, we find that both high- and low-mass XRBs show clear
concentrations towards the galactic plane and bulge.We also compare XRB
distributions under the galactic potential with a dark matter halo and the
modified Newtonian dynamics potential, and we suggest that the difference may
serve as potential evidence to discriminate between these two types of model.
