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arXiv · 2112.03795

Renormalization of the axial current operator in dimensional regularization at four-loop in QCD

Long Chen·Michał Czakon
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Abstract

We provide the renormalization constants of the axial current operators, both singlet and non-singlet, in dimensional regularization up to four-loop order in QCD, determined using the off-shell Ward-Takahashi identity for an axial current with a non-anticommuting $\gamma_5$. A possible application of the result for the singlet axial current operator is the extraction of the non-decoupling mass logarithms in the axial quark form factors.

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Long Chen, Michał Czakon. 2021-12-07. Renormalization of the axial current operator in dimensional regularization at four-loop in QCD. https://doi.org/10.1007/jhep01(2022)187

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