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arXiv · 2112.01200

Novel and self-consistency analysis of the QCD running coupling $\alpha_s(Q)$ in both the perturbative and nonperturbative domains

Abstract

The QCD coupling $\alpha_s$ is the most important parameter for achieving precise QCD predictions. By using the well measured effective coupling $\alpha^{g_1}_{s}(Q)$ defined from the Bjorken sum rules as a basis, we suggest a novel and self-consistency way to fix the $\alpha_s$ at all scales: The QCD light-front holographic model is adopted for its infrared behavior, and the fixed-order pQCD prediction under the principle of maximum conformality (PMC) is used for its high-energy behavior. Using the PMC scheme-and-scale independent perturbative series, and by transforming it into the one under the physical $V$-scheme, we observe that a precise $\alpha_s$ running behavior in both the perturbative and nonperturbative domains with a smooth transition from small to large scales can be achieved.

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Qing Yu, Hua Zhou, Xu-Dong Huang, Jian-Ming Shen, Xing-Gang Wu. 2021-12-02. Novel and self-consistency analysis of the QCD running coupling $\alpha_s(Q)$ in both the perturbative and nonperturbative domains. https://doi.org/10.1088/0256-307x%2F39%2F7%2F071201

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