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arXiv · 2102.08225

Reduction of planar double-box diagram for single-top production via auxiliary mass flow

Najam ul Basat·Zhao Li·Yefan Wang
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Abstract

The single-top production is an important process at the LHC to test the Standard Model (SM) and search for the new physics beyond the SM. Although the complete next-to-next-to-leading order (NNLO) QCD correction to the single-top production is crucial, this calculation is still challenging at present. In order to efficiently reduce the NNLO single-top amplitude, we improve the auxiliary mass flow (AMF) method by introducing the $\epsilon$ truncation. For demonstration we choose one typical planar double-box diagram for the $tW$ production. It is shown that one coefficient of the form factors on its amplitude can be systematically reduced into the linear combination of 198 scalar integrals.

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Najam ul Basat, Zhao Li, Yefan Wang. 2021-02-16. Reduction of planar double-box diagram for single-top production via auxiliary mass flow. https://doi.org/10.1103/physrevd.104.056020

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