Highly damped quasinormal modes of Kerr black holes: A complete numerical investigation

We compute for the first time very highly damped quasinormal modes of the (rotating) Kerr black hole. Our numerical technique is based on a decoupling of the radial and angular equations, performed using a large-frequency expansion for the angular separation constant (s)A(lm). This allows us to go much further in overtone number than ever before. We find that the real part of the quasinormal frequencies approaches a nonzero constant value which does not depend on the spin s of the perturbing field or on the angular index l: omega(R)=m (omega) over bar (a). We numerically compute (omega) over bar (a). Leading-order corrections to the asymptotic frequency are likely to be similar to1/omega(I). The imaginary part grows without bound, the spacing between consecutive modes being a monotonic function of a.