The strong coupling constant at large distances
نویسندگان
چکیده
In this paper we discuss effective strong coupling constants. Those are well behaved in the low-Q2 domain, contrarily to αs from pQCD. We present an extraction of an effective strong coupling constant from Jefferson Lab polarized data at intermediate and low Q2. We also show how these data, together with spin sum rules, allow us to obtain the effective coupling constant over the entire Q2 range. We then discuss the relation between the experimentally extracted coupling constant and theoretical calculations at low Q2. We conclude on the importance of such study for the application of the AdS/CFT correspondence to QCD.
منابع مشابه
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A striking contradiction between lattice short range static potential (n f = 0) and standard perturbative potential, observed in Ref. [18], is investigated in the framework of the background perturbation theory. With the use of the background coupling˜α B (r) which contains the only background parameter-mass m B , fixed by fine structure fit in bottomonium, the lattice data are nicely explained...
متن کاملar X iv : h ep - p h / 01 04 09 7 v 2 2 9 M ay 2 00 1 Freezing of QCD coupling affects the short distance static potential
A striking contradiction between lattice short range static potential (n f = 0) and standard perturbative potential, observed in Ref. [18], is investigated in the framework of the background perturbation theory. With the use of the background coupling˜α B (r) which contains the only background parameter-mass m B , fixed by fine structure fit in bottomonium, the lattice data are nicely explained...
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