Scattering of scalar waves from a Schwarzschild black hole

Abstract

The scattering of scalar waves from a Schwarzschild black hole is investigated for wavelengths much less than the graviational radius (r_s). Explicit expressions for scattering parameters are obtained for two cases: high angular momenta and low angular momenta. In the first case we obtain the phase shifts and absorption coefficient with the JWKB method. The elastic differential cross section and the total absorption cross section are also calculated. For low angular momenta we present a method based in the DWBA (distorted wave Born approximation). With this method, the phase shifts and the absorption coefficients are obtained.