Two-loop amplitude generation in OpenLoops

Abstract

Numerical tools, such as OpenLoops, provide NLO scattering amplitudes for a very wide range of hard scattering amplitudes in a fully automated way. In order to match the numerical precision of current and future experiments, however, the higher precision of NNLO calculations is essential, and their automation in a similar tool highly desirable. In our approach, D-dimensional amplitudes are decomposed into loop-momentum tensor integrals with coefficients constructed in four dimensions and rational terms. We present a fully generic algorithm for the efficient numerical construction of the tensor coefficients, which constitutes an important building block for an automated NNLO tool.

arXiv commentContribution to the proceedings of the 15th International Symposium on Radiative Corrections: Applications of Quantum Field Theory to Phenomenology (RADCOR + LoopFest 2021); v2: Typos fixed, reference updated

References in corpus (11)

• Scattering Amplitudes with Open Loops
• Collier: a fortran-based Complex One-Loop LIbrary in Extended Regularizations
• OpenLoops 2
• OneLOop: for the evaluation of one-loop scalar functions
• On the Rational Terms of the one-loop amplitudes
• On-the-fly reduction of open loops
• Feynman Rules for the Rational Part of the QCD 1-loop amplitudes
• Feynman rules for the rational part of the Electroweak 1-loop amplitudes
• Primary Feynman rules to calculate the epsilon-dimensional integrand of any 1-loop amplitude
• Two-Loop Rational Terms in Yang-Mills Theories
• Rational Terms of UV Origin at Two Loops