Generating QCD amplitudes in the color-flow basis with MadGraph

Abstract

We propose to make use of the off-shell recursive relations with the color-flow decomposition in the calculation of QCD amplitudes on MadGraph. We introduce colored quarks and their interactions with nine gluons in the color-flow basis plus an Abelian gluon on MadGraph, such that it generates helicity amplitudes in the color-flow basis with off-shell recursive formulae for multi-gluon sub-amplitudes. We demonstrate calculations of up to 5-jet processes such as $gg\to 5g$, $u\bar{u}\to 5g$ and $uu\to uuggg$. Although our demonstration is limited, it paves the way to evaluate amplitudes with more quark lines and gluons with Madgraph.

29 pages, 13 figures

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Cited by in corpus (3)

• QCD in the Color-Flow Representation
• Search for Mono-Higgs Signals in $b\bar{b}$ Final States Using Deep Neural Networks
• The colour matrix at next-to-leading-colour accuracy for tree-level multi-parton processes