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arXiv · 0901.2190

The strong coupling constant at large distances

A. Deur
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Abstract

In this paper we discuss effective strong coupling constants. Those are well behaved in the low-Q^2 domain, contrarily to alpha_s from pQCD. We present an extraction of an effective strong coupling constant from Jefferson Lab polarized data at intermediate and low Q^2. We also show how these data, together with spin sum rules, allow us to obtain the effective coupling constant over the entire Q^2 range. We then discuss the relation between the experimentally extracted coupling constant and theoretical calculations at low Q^2. We conclude on the importance of such study for the application of the AdS/CFT correspondence to QCD.

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A. Deur. 2009-01-16. The strong coupling constant at large distances. https://doi.org/10.1063/1.3215646

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