Acceleration of binary X-ray sources by their radiation

We consider a case where the magnetic field of a neutron star in an X-ray binary system differs from a dipole field. This difference gives rise to an asymmetry in the X-ray radiation from the system and, consequently, to an accelerating force. After averaging over the rotation period of the neutron star, the component of the force along its spin axis remains. Its magnitude, F=xi L-X/c (where L-X is the total X-ray luminosity of the neutron star, and xi is the radiation asymmetry coefficient), can exceed the force of gravitational attraction of the binary system to the Galaxy. This effect is most important for low-mass X-ray binary systems at the stage of intense accretion of matter onto the neutron stars. Such systems form the Galactic halo, while some of them go away into intergalactic space.