Integral Coefficients for One-Loop Amplitudes
arXiv:0711.4284 · doi:10.1088/1126-6708/2008/02/095
Abstract
We present a set of algebraic functions for evaluating the coefficients of the scalar integral basis of a general one-loop amplitude. The functions are derived from unitarity cuts, but the complete cut-integral procedure has been carried out in generality so that it never needs to be repeated. Where the master integrals are known explicitly, the results here can be used as a black box with tree-level amplitudes as input and one-loop amplitudes as output.
32 pages, 1 figure