DETERMINATION OF THE QCD COUPLING αs
نویسنده
چکیده
Theoretical basics and experimental determinations of the coupling parameter of the Strong Interaction, αs, are reviewed. The world average value of αs, expressed at the energy scale of the rest mass of the Z boson, is determined from analyses which are based on complete NNLO perturbative QCD. The result is αs(MZ0) = 0.1184 ± 0.0031. No significant deviations or systematic biases of subsamples of experimental results are found. From the observed energy dependence of αs, which is in excellent agreement with the expectations of QCD, the number of colour degrees of freedom can be constrained to Nc = 3.03± 0.12. MPI-PhE/2000-07 April 2000
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تاریخ انتشار 2008