Second Order QCD Corrections to Γ ( t → Wb )
نویسندگان
چکیده
Corrections of O(α 2 s) to the decay of the top quark into a W boson and a bottom quark are calculated. The method is based on an expansion of the top quark propa-gator for small external momentum, q, as compared to the top quark mass, M t. The physical point q 2 = M 2 t is reached through Padé approximations. The described method allows to take effects induced by a finite W boson mass into account. The numerical relevance of the result is discussed. Important cross-checks against recent results for the decay rate b → ul¯ ν and the two-loop QED corrections to µ-decay are performed.
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تاریخ انتشار 1999