A residue calculus for root systems

Abstract

Let V be a nite dimensional real vector space on which a root system is given. Consider a meromorphic function ' on VC = V +iV , the singular locus of which is a locally nite union of hyperplanes of the form f 2 VC j h; i = sg, 2 , s 2 R. Assume ' is of suitable decay in the imaginary directions, so that integrals of the form R +iV '() d make sense for generic 2 V . A residue calculus is developed that allows shifting . This residue calculus can be used to obtain Plancherel and Paley{Wiener theorems on semisimple symmetric spaces.