THREE-LOOP RUNNING OF THE STRONG COUPLING CONSTANT AND THE MASS OF THE b QUARK IN THE SUPERSYMMETRIC QCD
نویسنده
چکیده
Supersymmetric extension of the QCD (SQCD) is considered, and the scale dependence of some important parameters, i.e., strong coupling αs and b-quark running mass mb, is studied with the help of three-loop renormalization group equations. Fiveavour QCD is considered as a lowenergy effective theory of SQCD, and two-loop decoupling (threshold) effects are taken into account. Variations in running αs and mb at the GUT scale μGUT = 1016 GeV due to uncertainties in the initial experimental data and the ambiguities in the decoupling scale are analyzed for a particular point of the parameter space. Comparison with known results is given.
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