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arXiv · 2408.11190

Light quark loops in $K^\pm \to \pi^\pm \nu\bar\nu$ from vector meson dominance and update on the Kaon Unitarity Triangle

E. Lunghi·A. Soni
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Abstract

We use vector meson dominance to calculate non-perturbative contributions to the branching ratio of the rare decay $K^\pm \to \pi^\pm \nu\bar \nu$ stemming from matrix elements involving up-quark loops. The importance of this observable as well as of $K^0 \to \pi^0 l^+ l^-$ and of the direct CP violation parameter $\epsilon_K^{\prime}$ is then discussed in the context of a Unitarity Triangle sqtudy based on Kaon sector observables only.

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E. Lunghi, A. Soni. 2024-08-20. Light quark loops in $K^\pm \to \pi^\pm \nu\bar\nu$ from vector meson dominance and update on the Kaon Unitarity Triangle. https://arxiv.org/abs/2408.11190

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