New analytic running coupling in spacelike and timelike regions
نویسنده
چکیده
The model for the QCD analytic running coupling, proposed recently, is extended to the timelike region. This running coupling naturally arises under unification of the analytic approach to QCD and the renormalization group (RG) formalism. A new method for determining the coefficients of the “analytized” RG equation is elaborated. It enables one to take into account the higher loop contributions to the new analytic running coupling in a consistent way. It is shown that the difference between the values of the new analytic running coupling in respective spacelike and timelike regions is rather valuable for intermediate energies. It is essential for the correct extracting of the running coupling from experimental data. PACS number(s): 11.15.Tk, 11.55.Fv, 12.38.Lg, 12.39.Pn Typeset using REVTEX ∗Electronic address: [email protected]
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تاریخ انتشار 2001