Scattering of High Speed Particles in the Kerr Gravitational Field
  We calculate the angles of deflection of high speed particles projected in an arbitrary direction into the Kerr gravitational field. This is done by first calculating the light-like boost of the Kerr gravitational field in an arbitrary direction and then using this boosted gravitational field as an approximation to the gravitational field experienced by a high speed particle. In the rest frame of the Kerr source the angles of deflection experienced by the high speed test particle can then easily be evaluated. 
C. Barrab\`es and P. A. Hogan