Standard Model and New Physics contributions to KL and KS into four leptons
نویسندگان
چکیده
We study the KL and KS decays into four leptons (eēeē, μμ̄μμ̄, eēμμ̄) where we use a form factor motivated by vector meson dominance, and show the dependence of the branching ratios and spectra from the slopes. A precise determination of short distance contribution to KL → μμ is affected by our ignorance on the sign of the amplitude A(KL → γγ) but we show a possibility to measure the sign of this amplitude by studying KL and KS decays in four leptons. We also investigate the effect of New Physics contributions for these decays PACS 12.39.Fe · 13.20.Eb
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