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arXiv · 1906.11862

A numerical evaluation of planar two-loop helicity amplitudes for a W-boson plus four partons

Heribertus Bayu Hartanto·Simon Badger·Christian Brønnum-Hansen·Tiziano Peraro
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Abstract

We present the first numerical results for the two-loop helicity amplitudes for the scattering of four partons and a W-boson in QCD. We use a finite field sampling method to reduce directly from Feynman diagrams to the coefficients of a set of master integrals after applying integration-by-parts identities. Since the basis of master integrals is not yet fully known analytically, we identify a set of master integrals with a simple divergence structure using local numerator insertions. This allows for accurate numerical evaluation of the amplitude using sector decomposition methods.

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Heribertus Bayu Hartanto, Simon Badger, Christian Brønnum-Hansen, Tiziano Peraro. 2019-06-27. A numerical evaluation of planar two-loop helicity amplitudes for a W-boson plus four partons. https://arxiv.org/abs/1906.11862

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