Muon decays with nonconservation of lepton number in the model with minimal quark-lepton symmetry

The processes μ → eγ, μ → eγγ, and μ → ee 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 Γ(μ → ee bar e) much-gt Γ(μ → eγγ) much-gt Γ(μ → eγ) 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 μe conversion on nuclei and from a cosmological estimate for the decay make it possible to establish upper bounds for the branching ratios of the decays μ → eγγ (10-17) and μ → ee bar e(10-14). 16 refs., 4 figs