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Non-singlet structure functions beyond the next-to-next-to leading order

W. L. van Neerven·A. Vogt
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Abstract

We study the evolution of the flavour non-singlet deep-inelastic structure functions F_{2,NS} and F_3 at the next-to-next-to-next-to-leading order (N^3LO) of massless perturbative QCD. The present information on the corresponding three-loop coefficient functions is used to derive approximate expressions of these quantities which prove completely sufficient for values x > 10^{-2} of the Bjorken variable. The inclusion of the N^3LO corrections reduces the theoretical uncertainty of alpha_s determinations from non-singlet scaling violations arising from the truncation of the perturbation series to less than 1%. We also study the predictions of the soft-gluon resummation, of renormalization-scheme optimizations by the principle of minimal sensitivity (PMS) and the effective charge (ECH) method, and of the Pade' summation for the structure-function evolution kernels. The PMS, ECH and Pade' approaches are found to facilitate a reliable estimate of the corrections beyond N^3LO.

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W. L. van Neerven, A. Vogt. 2001-03-12. Non-singlet structure functions beyond the next-to-next-to leading order. https://doi.org/10.1016/s0550-3213(01)00158-4

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