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arXiv · 1004.5280

QCD Effective Coupling in the Infrared Region

Gurjav Ganbold
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Abstract

We estimate the QCD effective charge $\alpha_s$ in the low-energy region by exploiting the conventional meson spectrum within a relativistic quantum-field model based on analytic confinement. The ladder Bethe-Salpeter equation is solved for the masses of two-quark bound states. We found a new, independent and specific infrared-finite behavior of QCD coupling below energy scale 1 GeV. Particularly, an infrared-fixed point is extracted at $\alpha_s(0)\simeq 0.757$ for confinement scale $\Lambda=345$ MeV. As an application, we estimate masses of some intermediate and heavy mesons and obtain results in reasonable agreement with recent experimental data.

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Gurjav Ganbold. 2010-04-29. QCD Effective Coupling in the Infrared Region. https://doi.org/10.1103/physrevd.81.094008

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