NONFACTORIZABLE CORRECTIONS TO W-PAIR PRODUCTION - METHODS AND ANALYTIC RESULTS

In this paper we present two methods to evaluate non-factorizable corr ections to pair-production of unstable particles. The methods are illu strated in detail for W-pair-mediated four-fermion production. The res ults are valid a few widths above threshold, but not at threshold. One method uses the decomposition of n-point scalar functions for virtual and real photons, and can therefore be generalized to more complicate d final states than four fermions. The other technique is an elaborati on on a method known from the literature and serves as a useful check. Applications to other processes than W-pair production are briefly me ntioned. (C) 1997 Elsevier Science B.V.