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Probing Lepton-number/flavour-violation in Semileptonic Tau Decays into Two Mesons

A. Ilakovac
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Abstract

The evaluation, systematic analysis and numerical study of the semileptonic $τ$-lepton decays with two mesons in the final state has been made in the frame of the standard model extended by right handed neutrinos. In the analysis, heavy-neutrino nondecoupling effects, finite quark masses, quark and meson mixings, finite widths of vector mesons, chiral symmetry breakings in vector-meson--pseudoscalar-meson vertices and effective Higgs-boson--pseudoscalar-meson couplings have been included. Numerical estimates reveal that the decays $τ^-\to e^-π^-π^+$, $τ^-\to e^-K^-K^+$ and $τ^-\to e^-K^0\bar{K}^0$ have branching ratios of the order of $10^{-6}$, close to present-day experimental sensitivities.

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A. Ilakovac. 1996-08-02. Probing Lepton-number/flavour-violation in Semileptonic Tau Decays into Two Mesons. https://doi.org/10.1103/physrevd.54.5653

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