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Towards a quantitative understanding of the Delta I=1/2 rule

P. Hernandez
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Abstract

A recently proposed strategy to quantify the role of the charm quark mass in the $ΔI=1/2$ rule is reviewed. Results for the low-energy couplings of the $ΔS=1$ chiral effective Hamiltonian in a theory with a light charm quark (GIM limit) are obtained through a matching of three-point correlation functions computed in Chiral Perturbation Theory and in quenched lattice QCD. We observe a large $ΔI=1/2$ enhancement, which is not large enough to explain the experimental result, but suggests significant long-distance contributions to the physical $ΔI=1/2$ which are unrelated to penguin contractions or operators.

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P. Hernandez. 2006-10-31. Towards a quantitative understanding of the Delta I=1/2 rule. https://arxiv.org/abs/hep-lat/0610129

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