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arXiv · 1812.11818

Five-loop contributions to low-N non-singlet anomalous dimensions in QCD

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

We present the first calculations of next-to-next-to-next-to-next-to-leading order (N^4LO) contributions to anomalous dimensions of spin-N twist-2 operators in perturbative QCD. Specifically, we have obtained the respective non-singlet quark-quark anomalous dimensions at N=2 and N=3 to the fifth order in the strong coupling alpha_s. These results set the scale for the N^4LO contributions to the evolution of the non-singlet quark distributions of hadrons outside the small-x region, and facilitate a first approximate determination of the five-loop cusp anomalous dimension. While the N^4LO coefficients are larger than expected from the lower-order results, their inclusion stabilizes the perturbative expansions for three or more light flavours at a sub-percent accuracy for alpha_s < 0.3.

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F. Herzog, S. Moch, B. Ruijl, T. Ueda, J. A. M. Vermaseren, A. Vogt. 2018-12-31. Five-loop contributions to low-N non-singlet anomalous dimensions in QCD. https://doi.org/10.1016/j.physletb.2019.01.060

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