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arXiv · hep-ph/0003258

$K_{\ell 4}$ Form-Factors and $π$-$π$ Scattering

G. Amoros·J. Bijnens·P. Talavera
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Abstract

The $F$ and $G$ form-factors of $K_{\ell4}$ and the quark condensates are calculated to ${\cal O}(p^6)$ in Chiral Perturbation Theory (CHPT). Full formulas are presented as much as possible. A full refit of most of the ${\cal O}(p^4)$ CHPT parameters is done with a discussion of all inputs and underlying assumptions. We discuss the consequences for the vacuum expectation values, decay constants, pseudoscalar masses and $π$-$π$ scattering.

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G. Amoros, J. Bijnens, P. Talavera. 2000-03-27. $K_{\ell 4}$ Form-Factors and $π$-$π$ Scattering. https://doi.org/10.1016/s0550-3213(00)00366-7

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