Evaluation of Multiloop Diagrams via Lightcone Integration

When loop momenta of a Feynman or a nonabelian cut diagram are written in lightcone coordinates, integration over their + components can be performed using residue calculus. This yields a number of terms, in which the + components of their internal momenta are evaluated at the poles of appropriate internal lines. The challenge is to find these internal lines for an arbitrarily complicated multiloop diagram. We shall provide two ways for doing that. Typeset using REVTEX 1