• A.A. Gvozdev, A.V. Kuznetsov, N.V. Mikheev and L.A. Vassilevskaya
    Muon Decays with Nonconservation of Lepton Number in the Model with Minimal Quark-Lepton Symmetry $SU(4)_V \otimes SU(2)_L \otimes G_R$
    Yadernaya Fizika, 1995, V. 58, N 9, P. 1667-1671.
    [Physics of Atomic Nuclei, 1995, V. 58, N 9, P. 1571-1574.]

    • Abstract

    The processes $\mu \to e \gamma$, $\mu \to e \gamma \gamma$, and $\mu \to e e \bar e$ with nonconservation of lepton number are analyzed in the framework of quark-lepton symmetry of the Pati-Salam type with allowance for mixing in quark-lepton currents. The characteristic hierarchy of decay probabilities $\Gamma(\mu \to e e \bar e) \gg \Gamma(\mu \to e \gamma \gamma) \gg \Gamma(\mu \to e \gamma)$ is obtained in the model under consideration. The existing constraints on the leptoquark mass and on the elements of the mixing matrix (obtained from the width of $\mu e$ conversion on nuclei and from a cosmological estimate for the decay $\pi^0 \to \nu \bar{\nu}$ ) make it possible to establish upper bounds for the branching ratios of the decays $\mu \to e \gamma \gamma$ (10-17) and $\mu \to e e \bar e$ (10-14).

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