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arXiv · 1102.1599

Non-perturbative momentum dependence of the coupling constant and hadronic models

A. Courtoy·S. Scopetta·V. Vento
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Abstract

Models of hadron structure are associated with a hadronic scale which allows by perturbative evolution to calculate observables in the deep inelastic region. The resolution of Dyson-Schwinger equations leads to the freezing of the QCD running coupling (effective charge) in the infrared, which is best understood as a dynamical generation of a gluon mass function, giving rise to a momentum dependence which is free from infrared divergences. We use this new development to understand why perturbative treatments are working reasonably well despite the smallness of the hadronic scale.

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A. Courtoy, S. Scopetta, V. Vento. 2011-02-08. Non-perturbative momentum dependence of the coupling constant and hadronic models. https://doi.org/10.1140/epja/i2011-11049-8

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