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arXiv · 1702.01458

Five-loop fermion anomalous dimension for a general gauge group from four-loop massless propagators

P. A. Baikov·K. G. Chetyrkin·J. H. Kühn
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Abstract

We extend the ${\cal O}(α_s^5)$ result of the analytic calculation of the quark mass anomalous dimension in pQCD [1] to the case of a generic gauge group. We present explicit formulas which express the relevant renormalization constants in terms of four-loop massless propagators. We also use our result to shed new light on the old puzzle of the absence of even zetas in results of perturbative calculations for a class of physical observables.

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P. A. Baikov, K. G. Chetyrkin, J. H. Kühn. 2017-02-08. Five-loop fermion anomalous dimension for a general gauge group from four-loop massless propagators. https://doi.org/10.1007/jhep04(2017)119

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