Some Exact Results for Two-Loop Diagrams with Three and Four External Lines
arXiv:hep-ph/9307327
Abstract
Evaluation of three- and four-point diagrams with massless internal particles and arbitrary external momenta is considered. Exact results for some two-loop diagrams (planar and non-planar three-point contributions and the "double box" diagram) are obtained in terms of polylogarithms.
To appear in Proc. VII Intern. Workshop "High Energy Physics and Quantum Field Theory" (Sochi, Russia, October 1992), Yad.Fiz., v.56, No.11, p.172-179 (November 1993)