Exact matrix elements in supersymmetric theories

The lowest representatives of the form factors relative to the trace operators of N = 1 super sinh-Gordon model are exactly calculated. The novelty of their determination consists in solving a coupled set of unitarity and crossing equations. Analytic continuations of the form factors as functions of the coupling constant allows for the study of interesting models in a uniform way, among these the latest model of the Roaming series and the minimal supersymmetric models as investigated by Schoutens. A fermionic version of the c-theorem is also proved and the corresponding sum rule derived. (C) 1998 Elsevier Science B.V.