Bondi-Hoyle-Lyttleton accretion model for low-luminosity X-ray sources in globular clusters

We present a new model for low-luminosity X-ray sources in globular clusters, with L-X less than or similar to 10(34) ergs s(-1). The model we propose is that of a single neutron star accreting from cluster gas that has accumulated as a natural product of stellar evolution. An analytic luminosity function is derived under the assumption that the speed distribution of neutron stars in the central region of a cluster is described by a Maxwellian, and that the density and temperature of the gas are uniform. Predictions of the model and implications for the gas content of globular clusters are discussed.