  Starting with the Dirac equation outside the event horizon of a non-extreme
Kerr black hole, we develop a time-dependent scattering theory for massive
Dirac particles. The explicit computation of the modified wave operators at
infinity is done by implementing a time-dependent logarithmic phase shift from
the free dynamics to offset the long range term in the full Hamiltonian due to
the presence of the gravitational force. Analytical expressions for the wave
operators are also given.
