Decays ZH → Zγ and ZH → ZZ in the littlest Higgs model

Abstract

The study of the phenomenology of an extra neutral gauge boson, ZH, can help us to unravel the underlying theory from which this particle arises. We study the decay of such a particle into two neutral gauge bosons, ZH → Zγ and ZH → ZZ, in the littlest Higgs model. These decays are induced at the one-loop level by a fermion triangle and are interesting as they are strongly dependent on the mechanism of anomaly cancellation of the model. Other relevant tree-level two- and three-body ZH decays are also calculated. It is found that the branching ratios for the ZH → γZ decays can be as large as that of a tree-level three-body decay but the ZH → ZZ decay is very suppressed. We also discuss the experimental prospects for detecting these decays at the LHC.