ε′/ε in the standard model
نویسنده
چکیده
In (5), GF is the Fermi coupling, the functions zi(μ) and yi(μ) are the Wilson coefficients and τ = −VtdV ∗ ts/VudV ∗ us. According to the standard parameterization of the CKM matrix, in order to determine ε/ε , we only need to consider the yi(μ) components, which control the CP -violating part of the lagrangian. The coefficients yi(μ), and zi(μ) contain all the dependence of short-distance physics, and depend on the t,W, b, c masses, the intrinsic QCD scale ΛQCD, the γ5-scheme used in the regularization and the renormalization scale μ. They are known to the next-to-leading order (NLO) order in αs and αe [4]. The Qi in eq. (4) are the effective four-quark operators obtained in the standard model by integrating out the vector bosons and the heavy quarks t, b and c. A convenient and by now standard basis includes the following ten operators:
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