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arXiv · hep-ph/9603256

Determination of the Kobayashi-Maskawa-Cabibbo matrix element V_{us} under various flavor-symmetry-breaking models in hyperon semileptonic decays

R. Flores-Mendieta·A. Garcia·G. Sanchez-Colon
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Abstract

We study the success to describe hyperon semileptonic decays of four models that incorporate second-order SU(3) symmetry breaking corrections. The criteria to assess their success is by determining V_{us} in each of the three relevant hyperon semileptonic decays and comparing the values obtained with one another and also with the one that comes from K_{l3} decays. A strong dependence on the particular symmetry breaking model is observed. Values of V_{us} which do not agree with the one of K_{l3} are generally obtained. However, in the context of chiral perturbation theory, only the model whose corrections are O(m_s) and O(m_s^{3/2}) is successful. Using its predictions for the f_1 form factors one can quote a value of V_{us} from this model, namely, V_{us}=0.2176\pm 0.0026, which is in excellent agreement with the K_{l3} one.

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R. Flores-Mendieta, A. Garcia, G. Sanchez-Colon. 1998-03-14. Determination of the Kobayashi-Maskawa-Cabibbo matrix element V_{us} under various flavor-symmetry-breaking models in hyperon semileptonic decays. https://doi.org/10.1103/physrevd.54.6855

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