Adiabatic Radiation Reaction to Orbits in Kerr Spacetime

The geodesic motion of a point particle in Kerr geometry has three constants of motion, the energy E, the azimuthal angular momentum L, and the Carter constant Q. Under the adiabatic approximation, the radiation reaction effect is characterized by the time evolution of these constants. In this paper, we show that the scheme for evaluating them can be greatly simplified.