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arXiv · hep-ph/0307214

Semileptonic Hyperon Decays and CKM Unitarity

Nicola Cabibbo·Earl C. Swallow·Roland Winston
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Abstract

Using a technique that is not subject to first-order SU(3) symmetry breaking effects, we determine the $V_{us}$ element of the CKM matrix from data on semileptonic hyperon decays. We obtain $V_{us}$ =0.2250(27). This value is of similar precision to the one derived from $K_{l3}$, but higher and in better agreement with the unitarity requirement, $|V_{ud}|^2+|V_{us}|^2+|V_{ub}|^2=1$.

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Nicola Cabibbo, Earl C. Swallow, Roland Winston. 2004-05-07. Semileptonic Hyperon Decays and CKM Unitarity. https://doi.org/10.1103/physrevlett.92.251803

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