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Constraints on the form factors for K --> pi l nu and implications for V_us

Richard J. Hill
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Abstract

Rigorous bounds are established for the expansion coefficients governing the shape of semileptonic K-->pi form factors. The constraints enforced by experimental data from tau-->K pi nu eliminate uncertainties associated with model parameterizations in the determination of |V_us|. The results support the validity of a powerful expansion that can be applied to other semileptonic transitions.

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Richard J. Hill. 2006-12-01. Constraints on the form factors for K --> pi l nu and implications for V_us. https://doi.org/10.1103/physrevd.74.096006

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