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arXiv · 1712.06048

Bjorken sum rule in QCD with analytic coupling

C. Ayala·G. Cvetic·A. V. Kotikov·B. G. Shaikhatdenov
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Abstract

We present details of study of the Bjorken polarized sum rule carried out recently in [1] within the range of energies where the data were collected by JLAB collaboration, 0.05 GeV2 < Q2 < 3 GeV2. Three approaches to QCD with analytic (holomorphic) coupling are considered: Analytic Perturbation Theory (APT), Two-delta analytic QCD, and Three-delta lattice-motivated analytic QCD in the three-loop and four-loop MiniMOM schemes. The new frameworks with respective couplings give results which agree well with the experimental data for 0.5 GeV2 < Q2 < 3GeV2 already when only one higher-twist term is taken into account.

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C. Ayala, G. Cvetic, A. V. Kotikov, B. G. Shaikhatdenov. 2017-12-17. Bjorken sum rule in QCD with analytic coupling. https://doi.org/10.1088/1742-6596%2F938%2F1%2F012055

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