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arXiv · hep-ph/9910490

Value of $α_s$ and high twists from combined analysis $e-μ$ DIS data

Abstract

We perform a NLO QCD analysis of the combined SLAC-BCDMS-NMC-E665-H1-ZEUS data on inclusive deep inelastic cross section. Particular attention was paid to the extraction of strong coupling constant $α_s$ and high twist (HT) contribution to the structure functions $F_2$ and $F_L$. It was shown that at small and moderate x there is a visible dependence of the extracted values of HT contribution to $F_2$ on the QCD renormalization scale, which indicates that in this region extracted HT can absorb NNLO QCD corrections. At larger x the dependence of HT on the renormalization scale is negligible and the influence of NNLO correction on their values should be less significant. The value of $α_s(M_Z)=0.1159\pm0.0031$ (total) is obtained, where the error includes statistical, systematical and theoretical uncertainties.

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BibTeXRIS

Alekhin Sergey. 1999-10-26. Value of $α_s$ and high twists from combined analysis $e-μ$ DIS data. https://arxiv.org/abs/hep-ph/9910490

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