We present here a computer model of the distribution of the luminosity produced by old, isolated neutron stars accreting from the interstellar medium. The system of differential equations was solved numerically. Stars were born in the Galactic plane with a specified velocity distribution corresponding to non-symmetrical supernova explosions. In our model, we assumed that the birth rate of neutron stars is proportional to the square of the local density.
Luminosity is given in arbitrary units.