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The QCD analytic effective charge and its dependence on the pion mass

A. V. Nesterenko·J. Papavassiliou
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Abstract

A new model for the QCD analytic running coupling, which incorporates the effects due to the $π$ meson mass, is proposed. The properties of this invariant charge in spacelike and timelike regions are examined. Its main distinctive features are a finite infrared limiting value, which depends on the pion mass, and the "plateau-like" behavior in the deep infrared domain of the timelike region.

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A. V. Nesterenko, J. Papavassiliou. 2004-09-18. The QCD analytic effective charge and its dependence on the pion mass. https://doi.org/10.1142/s0217751x05028296

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