Hide and seek with the third family hypercharge model’s Z′ at the large hadron collider

Abstract

The Third Family Hypercharge Model predicts a Z′$$Z^\prime $$ gauge boson with flavour dependent couplings which has been used to explain anomalies in meson decay processes which involve the b→sμ+μ-$$b\rightarrow s\mu ^+\mu ^-$$ transition. The model predicts that a TeV-scale Z′$$Z^\prime $$ should decay to particle-antiparticle pairs of muons, taus, top quarks and bottom quarks with appreciable branching ratios. We reinterpret various ATLAS and CMS search limits for Z′$$Z^\prime $$ production followed by such decays at the LHC over a parameter space of the model that results from a successful combined fit to the b→sl+l-$$b\rightarrow s l^+ l^-$$ data and precision electroweak observables. Current exclusions in parameter space and expected sensitivities of the various different channels in the high-luminosity run are compared. We find that the high-luminosity run of the LHC will significantly increase the sensitivity to the model beyond the existing empirical limits, which we find to be surprisingly weak.