Spin-zero-exchange model of weak interactions

Abstract

A renormalizable model in which weak interactions are mediated by spin-0 exchange rather than by spin-1 exchange is studied. The lowest-order diagrams for ..mu.. and ..beta.. decay are box diagrams. Neutrino cross sections off leptons and hadrons are calculated for the effective charged and neutral currents of the model. Weak corrections to e/sup +/e/sup -/ ..-->.. ..mu../sup +/..mu../sup -/ and higher-order contributions to ..mu.. decay are also calculated. Neutral-current effects are predicted to be small for neutrinos on lepton targets and large for e/sup +/e/sup -/ ..-->.. ..mu../sup +/..mu../sup -/; their strength is fixed by ..nu..--hadron scattering. In particular, there is a sizeable suppression of ..nu../sub ..mu../e scattering and a large enhancement of the asymmetry in e/sup +/e/sup -/ ..-->.. ..mu../sup +/..mu../sup -/. The only troublesome prediction is a parameter-free value of 1 for the ratio sigma (..nu../sub ..mu../ + N ..-->.. ..nu../sub ..mu../ + X) / sigma (anti ..nu../sub ..mu../ + N ..-->.. anti ..nu../sub ..mu../ + X). On the whole, however, the model provides a sensible, renormalizable alternative to the gauge theories. (AIP)