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arXiv · 0805.4119

Electroweak Corrections to the Charm Quark Contribution to K+ -> pi+ nu nu-bar

Joachim Brod·Martin Gorbahn
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Abstract

We compute the leading-log QED, the next-to-leading-log QED-QCD, and the electroweak corrections to the charm quark contribution relevant for the rare decay K+ -> pi+ nu nu-bar. The corresponding parameter P_c(X) is increased by up to 2% with respect to the pure QCD estimate to P_c(X) = 0.372 +- 0.015 for m_c(m_c)= (1.286 +- 0.013) GeV, alphas(M_Z) = 0.1176 +- 0.0020 and |V_us| = 0.2255. For the branching ratio we find B(K+ -> pi+ nu nu-bar) = (8.5 +- 0.7)*10^{-11}, where the quoted uncertainty is dominated by the CKM elements.

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Joachim Brod, Martin Gorbahn. 2008-05-27. Electroweak Corrections to the Charm Quark Contribution to K+ -> pi+ nu nu-bar. https://doi.org/10.1103/physrevd.78.034006

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