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Parton densities and structure functions beyond the next-to-leading order

W. L. van Neerven·A. Vogt
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Abstract

We briefly discuss recent results on the evolution of unpolarized parton densities and structure functions in massless perturbative QCD. Present partial results on the next-to-next-to-leading order (NNLO) evolution kernels prove sufficient for reliable calculations at not too small values of the Bjorken variable, x > 10^-3. One order more can be taken into account at x >= 0.2. Inclusion of these terms considerably reduces the main theoretical uncertainties of determinations of alpha_s (to about 1% at the Z-mass) and the parton densities from structure functions.

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W. L. van Neerven, A. Vogt. 2000-06-20. Parton densities and structure functions beyond the next-to-leading order. https://doi.org/10.1016/s0920-5632(00)00836-7

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