On the rare $K \to π\bar l l$ decays

David Greynat

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arXiv · hep-ph/0411210

On the rare $K \to π\bar l l$ decays

David Greynat

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Abstract

In this talk, we present our recent work on the $K\raπ\bar{l} l$ decays in a combined framework of chiral perturbation theory and Large--$N_c$ QCD under the dominance of a minimal narrow resonance structure. The proposed description reproduces very well the experimental Br$(K^+\raπ^+ e^+ e^-)$ and Br$(K_S\raπ^0 e^+ e^-)$. Predictions for the $K\raπμ^{+}μ^{-}$ modes are also obtained and we can conclude to the constructive type for the interference between the {\it direct} and {\it indirect} CP--violation amplitudes in $K_L\raπ^0 e^+ e^-$.

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David Greynat. 2004-11-16. On the rare $K \to π\bar l l$ decays. https://arxiv.org/abs/hep-ph/0411210

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