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arXiv · 2202.00703

Two-loop amplitude generation in OpenLoops

Stefano Pozzorini·Natalie Schär·Max F. Zoller
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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.

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Stefano Pozzorini, Natalie Schär, Max F. Zoller. 2022-02-01. Two-loop amplitude generation in OpenLoops. https://doi.org/10.21468/scipostphysproc.7.018

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