K + → π + ν¯ν Beyond Leading Logs and Vtd ∗
نویسنده
چکیده
The calculation of QCD corrections beyond the leading logarithmic approximation for the short-distance dominated rare decay K → πνν̄ is summarized. This analysis requires the complete O(αs) corrections to the top contribution to all orders in the top-quark mass and a two-loop renormalization group (RG) calculation for the charm contribution. The inclusion of these QCD corrections reduces considerably the theoretical uncertainty in calculating B(K → πνν̄). Implications for the determination of Vtd from this decay are discussed. ∗Talk given at the International Europhysics Conference on High Energy Physics, Marseille,
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