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arXiv · hep-ph/0111272

Updating V_us from kaon semileptonic decays

G. Calderon·G. Lopez Castro
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Abstract

We update the determination of |V_us| using semielectronic and semimuonic decays of K mesons. A modest improvement of 15% with respect to its present value is obtained for the error bar of this matrix element when we combine the four available semileptonic decays. The combined effects of long-distance radiative corrections and nonlinear terms in the vector form factors can decrease the value of |V_us| by up to 1%. Refined measurements of the decay widths and slope form factors in the semimuonic modes and a more accurate calculation of vector form factors at zero momentum transfer can push the determination of |V_us| at a few of percent level.

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G. Calderon, G. Lopez Castro. 2001-11-22. Updating V_us from kaon semileptonic decays. https://doi.org/10.1103/physrevd.65.073032

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