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arXiv · 2102.12880

The three-loop singlet contribution to the massless axial-vector quark form factor

T. Gehrmann·A. Primo
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Abstract

We compute the three-loop corrections to the quark axial vector form factor in massless QCD, focusing on the pure-singlet contributions where the axial vector current couples to a closed quark loop. Employing the Larin prescription for $\gamma_5$, we discuss the UV renormalization of the form factor. The infrared singularity structure of the resulting singlet axial-vector form factor is explained from infrared factorization, defining a finite remainder function.

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T. Gehrmann, A. Primo. 2021-02-25. The three-loop singlet contribution to the massless axial-vector quark form factor. https://doi.org/10.1016/j.physletb.2021.136223

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