Leptonic branching ratios of heavyZ0bosons

Abstract

In searching for ${Z}^{0}$ bosons heavier than that of the standard model, an assumption is made that these bosons have a significant branching ratio for the decay ${Z}^{0}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ or ${e}^{+}{e}^{\ensuremath{-}}$. This is of particular importance in searches involving hadron-hadron colliders. We examine the possibility that such heavy ${Z}^{0}$ bosons may prefer to decay into a pair of lighter charged gauge bosons ${Z}^{0}\ensuremath{\rightarrow}{W}^{+}{W}^{\ensuremath{-}}$ rather than into fermion pairs. In particular, in a recently proposed left-right-symmetric model, we examine how the decay ${Z}_{2}\ensuremath{\rightarrow}{{W}_{L}}^{+}{{W}_{L}}^{\ensuremath{-}}$ influences the ${Z}_{2}$ leptonic branching ratio, where ${Z}_{2}$ is the heavier of the two neutral gauge bosons.