Golem95: a numerical program to calculate one-loop tensor integrals with up to six external legs

TL;DR

Golem95 is a Fortran95 program that numerically evaluates one-loop tensor integrals with up to six external legs, avoiding inverse Gram determinants for stability, enabling fast calculations with massless internal particles.

Contribution

The paper introduces Golem95, a novel numerical tool for calculating one-loop tensor integrals with up to six external legs, improving stability and efficiency.

Findings

Numerical evaluation of tensor integrals up to six legs.

Stable calculations avoiding inverse Gram determinants.

Fast computation for massless internal particles.

Abstract

We present a program for the numerical evaluation of form factors entering the calculation of one-loop amplitudes with up to six external legs. The program is written in Fortran95 and performs the reduction to a certain set of basis integrals numerically, using a formalism where inverse Gram determinants can be avoided. It can be used to calculate one-loop amplitudes with massless internal particles in a fast and numerically stable way.