Numerical evaluation of multi-gluon amplitudes for High Energy Factorization
Description
Abstract We present a program to evaluate tree-level multi-gluon amplitudes with up to two of them off-shell. Furthermore, it evaluates squared amplitudes summed over colors and helicities for up to six external gluons. It employs both analytic expressions, obtained via BCFW recursion, and numerical BCFW recursion. It has been validated numerically with the help of an independent program employing numerical Dyson–Schwinger recursion. Title of program: AMP4HEF Catalogue Id: AEXF_v1_0 Nature of problem The numerical evaluation of matrix elements applicable in factorization prescriptions for the cross section calculation of hadron scattering processes that require off-shell partonic initial states. Versions of this program held in the CPC repository in Mendeley Data AEXF_v1_0; AMP4HEF; 10.1016/j.cpc.2015.06.023 This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2018)