Se p 20 04 RG solutions for α s at large N c in d = 3 + 1 QCD
نویسنده
چکیده
Solutions of RG equations for β(α) and α(Q) are found in the class of meromorphic functions satisfying asymptotic conditions at large Q (resp. small α), and analyticity properties in the Q 2 plane. The resulting α R (Q) is finite in the Euclidean Q 2 region and agrees well at Q ≥ 1 GeV with the M S α s (Q).
منابع مشابه
RG Solutions for α s at large N c in d = 3 + 1 QCD
QCD is known to simplify at large Nc: i) the perturbation theory dictates that only planar diagrams survive in the leading order [1]; ii) assuming that confinement exists also in the limit Nc → ∞, the spectrum of mesons and glueballs consists of bound-state poles, and the decay width vanishes at large Nc[1, 2, 3]. In the 1+1 QCD this property was proved both analytically and numerically [3] (fo...
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