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arXiv · 1103.4855

Dispersive representation of the scalar and vector Kpi form factors for tau --> K pi nu_tau and K_{l3} decays

Véronique Bernard·Diogo R. Boito·Emilie Passemar
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Abstract

Recently, the tau --> K pi nu_tau decay spectrum has been measured by the Belle and BaBar collaborations. In this work, we present an analysis of such decays introducing a dispersive parametrization for the vector and scalar Kpi form factors. This allows for precise tests of the Standard Model. For instance, the determination of f_+(0)|V_{us}| from these decays is discussed. A comparison and a combination of these results with the analyses of the K_{l3} decays is also considered.

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Véronique Bernard, Diogo R. Boito, Emilie Passemar. 2011-03-24. Dispersive representation of the scalar and vector Kpi form factors for tau --> K pi nu_tau and K_{l3} decays. https://doi.org/10.1016/j.nuclphysbps.2011.06.024

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