A straightforward SU(3) × U(1) model in which there is effectively one new neutral-current parameter (denoted by $R$) is shown to give the canonical neutrino neutral-current predictions for all values of $R$. For small $R$ the "low-energy" theory is essentially SU(2) × U(1) while for $R$ of the order of one it has a much richer "low-energy" gauge-boson mass spectrum. Even in the latter case, the predicted $e-d$ asymmetry agrees with experiment. It is interesting that the atomic-physics parity violation depends sensitively on $R$.

• Received 31 March 1980

DOI:https://doi.org/10.1103/PhysRevD.22.738