Muon Decay in AN SU2 X U(1) Gauge Theory with Spinor and Vector Higgs Fields and Massive Majorana Neutrinos.

This thesis investigates the implications for muon decay of a gauge theory that incorporates modifications to the standard electro-weak theory, the Weinberg-Salam model. The Higgs sector of the original model is broadened to include an isovector or triplet Higgs field. Such an addition naturally provides for massive Majorana-type neutrinos and permits the decay modes (mu) (--->) e(gamma) and (mu) (--->) 3e which would not otherwise be allowed. The particles most responsible for these decay modes are new, charged, physical, scalar Higgs particles not present in the Weinberg -Salam model. The decay rates found, although considerably more favorable to muon decay than the simple addition of neutrino mass to the standard theory, are found to be much below the present limits of experimental detectability. The lengthy calculations required, including the derivation and utilization of the relevant Feynman diagrams, are displayed in some detail.