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arXiv · 2403.12623

All-order Feynman rules for leading-twist gauge-invariant operators in QCD

G. Somogyi·S. Van Thurenhout
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Abstract

We present the Feynman rules for leading-twist gauge-invariant quark and gluon operators with an arbitrary number of total derivatives and applicable to any order in perturbation theory. This generalizes previous results and constitutes a necessary ingredient in the computation of the matrix elements of the corresponding operators. The results are written in a form appropriate for implementation in a computer algebra system. To illustrate the latter we provide implementations in Mathematica and FORM, which are made available at https://github.com/vtsam/NKLO.

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G. Somogyi, S. Van Thurenhout. 2024-03-19. All-order Feynman rules for leading-twist gauge-invariant operators in QCD. https://arxiv.org/abs/2403.12623

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