Quasi-normal modes of Schwarzschild-de Sitter black holes

The low-lying frequencies of characteristic quasi-normal modes (QNMs) of Schwarzschild-de Sitter (SdS) black holes have been calculated for fields of different spin using the sixth-order WKB approximation and the approximation by the Pbschl-Teller potential. The well-known asymptotic formula for large l is generalized here in a case of the SdS black hole. In the limit of the near extreme Lambda term the results given by both methods are in very good agreement, and in this limit fields of different spin decay with the same rate.