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I : Chiral Perturbation for Kaons II: The $ΔI=1/2$-rule in the Chiral Limit

Johan Bijnens
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Abstract

I : Chiral Perturbation Theory is introduced and its applications to semileptonic and nonleptonic kaon decays are discussed. II: The method of large $N_c$ is used to calculate $K\toππ$ nonleptonic matrix elements, in particular the matching procedure between long and short-distance evolution that takes all scheme dependence correctly into account is discussed. Numerical results reproduce the $ΔI=1/2$ rule without the introduction of any free parameters.

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Johan Bijnens. 1999-07-27. I : Chiral Perturbation for Kaons II: The $ΔI=1/2$-rule in the Chiral Limit. https://arxiv.org/abs/hep-ph/9907514

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