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arXiv · 1302.3952

The polarized Bjorken sum rule analysis: revised

V. L. Khandramai·O. P. Solovtsova·O. V. Teryaev
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Abstract

We present progress in the QCD analysis of the Bjorken sum rule at low momentum transfers. We study asymptotic structure of the perturbative QCD expansion at low $Q^2$ scales based on analysis of recent accurate data on the Bjorken sum rule and available now four-loop expression for the coefficient-function $C_{Bj}(Q^2)$. We demonstrate that the standard perturbative series for $C_{Bj}(Q^2)$ gives a hint to its asymptotic nature manifesting itself in the region $Q^2 \lesssim 1$ GeV$^2$. It is confirmed by the considered integral model for the perturbative QCD correction. We extract a value of higher-twist $\mu_4$ coefficient and study the interplay between higher orders and higher-twist contributions. Results of other approaches to the description of Bjorken sum rule data are discussed.

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V. L. Khandramai, O. P. Solovtsova, O. V. Teryaev. 2013-02-16. The polarized Bjorken sum rule analysis: revised. https://arxiv.org/abs/1302.3952

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