Hawking radiation of Dirac particles in a variable-mass Kerr space-time

The Hawking effect of Dirac particles in a variable-mass Kerr space-time is investigated by using a method called as the generalized tortoise coordina te transformation. The location and the temperature of the event horizon of the non-stationary Kerr black hole are derived. It is shown that the tempe rature and the shape of the event horizon depend not only on the time but a lso on the angle. However, the Fermi-Dirac spectrum displays a residual ter m which is absent from that of Bose-Einstein distribution.