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arXiv · 0705.0329

Bound state approach to the QCD coupling at low energy scales

M. Baldicchi·A. V. Nesterenko·G. M. Prosperi·D. V. Shirkov·C. Simolo
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Abstract

We exploit theoretical results on the meson spectrum within the framework of a Bethe-Salpeter (BS) formalism adjusted for QCD, in order to extract an ``experimental'' coupling α_s^{exp}(Q^2) below 1 GeV by comparison with the data. Our results for α_s^{exp}(Q^2) exhibit a good agreement with the infrared safe Analytic Perturbation Theory (APT) coupling from 1 GeV down to 200 MeV. As a main result, we claim that the combined BS-APT theoretical scheme provides us with a rather satisfactory correlated understanding of very high and low energy phenomena.

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M. Baldicchi, A. V. Nesterenko, G. M. Prosperi, D. V. Shirkov, C. Simolo. 2007-11-22. Bound state approach to the QCD coupling at low energy scales. https://doi.org/10.1103/physrevlett.99.242001

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