Quasinormal modes of black holes: The improved semianalytic approach

We extend the semianalytic technique of Iyer and Will for computing the complex quasinormal frequencies of black holes, omega, by constructing the Pade approximants of the (formal) series for omega(2). It is shown that for the (so-far best documented) quasinormal frequencies of the Schwarzschild and Reissner-Nordstrom black holes the Pade transforms P-6(6) and P-7(6) are, within the domain of applicability, always in excellent agreement with the numerical results. We argue that the method may serve as a black box with the potential Q(x) as an input and the accurate quasinormal modes as the output. The generalizations and modifications of the method are briefly discussed as well as the preliminary results for other classes of black holes.