Neutral currents in expanded gauge theories

Abstract

We show how the standard SU(2) \ifmmode\times\else\texttimes\fi{} U(1) gauge model may be generalized to include several neutral intermediate vector bosons, without changing the predictions of the model for neutral-current neutrino interactions. The expanded gauge models involve at least one neutral intermediate vector boson which is lighter than the ${Z}^{0}(80 \mathrm{GeV})$ of the standard model.