Neutrino oscillation interference phase in Kerr space--time

The mass neutrino interference phases along the null trajectory and the geodesic line in Kerr space--time are studied on the plane \theta=\pi/2. Because of the rotation object in Kerr space--time, a particle travelling along the radial geodesic must have a dragging effect produced by the angular momentum of the central object. We give the correction of the phase due to the rotation of the space--time. We find that the type-I interference phase along the geodesic remains the double of that along the null on the condition that the rotating quantity parameter a² is preserved and the higher order terms are negligible (e.g. a⁴). In addition, we calculate the proper oscillation length in Kerr space--time. All of our results can return to those in Schwarzschild space--time as the rotating parameter a approaches zero.