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Analytical approaches to the calculation of f+(0)

J. Portoles
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Abstract

Kl3 decays constitute, at present, the golden modes to extract |Vus| from experimental data. Its incertitude is dominated by the theoretical error in the determination of the vector form factor at zero transfer of momentum. I review the most relevant analytical approaches for the calculation of this parameter.

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J. Portoles. 2007-03-20. Analytical approaches to the calculation of f+(0). https://arxiv.org/abs/hep-ph/0703093

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