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arXiv · 2409.02870

Constraints for twist-two alien operators in QCD

G. Falcioni·F. Herzog·S. Moch·S. Van Thurenhout
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Abstract

Parton evolution equations in QCD are controlled by the anomalous dimensions of gauge-invariant twist-two spin-$N$ quark and gluon operators. Under renormalization, these mix with gauge-variant operators of the same quantum numbers, referred to as alien operators. Our work addresses the systematic study of these alien operators at arbitrary spin $N$, using generalized BRST symmetry relations to derive their couplings and Feynman rules at all values of $N$. We observe how the all-$N$ structure of the generalized (anti-)BRST constraints relates the couplings of alien operators with $n+1$ gluons to those with $n$ gluons. Realizing a bootstrap, we present all one-loop results necessary for performing the operator renormalization up to four loops in QCD.

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G. Falcioni, F. Herzog, S. Moch, S. Van Thurenhout. 2024-09-04. Constraints for twist-two alien operators in QCD. https://doi.org/10.1007/jhep11(2024)080

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