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arXiv · hep-ph/9711377

Long Distance Contribution to $K_L \to \ell^+ \ell^-$

G. Valencia
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Abstract

We revisit the calculation of the long distance contribution to $K_L \to μ^+ μ^-$. We discuss this process within the framework of chiral perturbation theory, and also using simple models for the $K_L γ^* γ^*$ vertex. We argue that it is unlikely that this mode can be used to extract information on short distance parameters. The process $K_L \to e^+ e^-$ is also long-distance dominated and we find that $B(K_L \to e^+ e^-) \approx 9 \times 10^{-12}$.

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G. Valencia. 1998-02-04. Long Distance Contribution to $K_L \to \ell^+ \ell^-$. https://doi.org/10.1016/s0550-3213(98)00116-3

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