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arXiv · 1801.06085

Four-loop results on anomalous dimensions and splitting functions in QCD

A. Vogt·S. Moch·B. Ruijl·T. Ueda·J. A. M. Vermaseren
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Abstract

We report on recent progress on the flavour non-singlet splitting functions in perturbative QCD. The~exact four-loop (N^3LO) contribution to these functions has been obtained in the planar limit of a large number of colours. Phenomenologically sufficient approximate expressions have been obtained for the parts not exactly known so far. Both cases include results for the four-loop cusp and virtual anomalous dimensions which are relevant well beyond the evolution of non-singlet quark distributions, for which an accuracy of (well) below 1% has now been been reached.

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A. Vogt, S. Moch, B. Ruijl, T. Ueda, J. A. M. Vermaseren. 2018-01-18. Four-loop results on anomalous dimensions and splitting functions in QCD. https://arxiv.org/abs/1801.06085

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