Hadron collider sensitivity to fat flavourful Z's for R-K(*)

Abstract

We further investigate the case where new physics in the form of a massive Z ′ particle explains apparent measurements of lepton flavour non-universality in B → K ( * ) l + l − decays. Hadron collider sensitivities for direct production of such Z ′ s have been previously studied in the narrow width limit for a μ + μ − final state. Here, we extend the analysis to sizeable decay widths and improve the sensitivity estimate for the narrow width case. We estimate the sensitivities of the high luminosity 14 TeV Large Hadron Collider (HL-LHC), a high energy 27 TeV LHC (HE-LHC), as well as a potential 100 TeV future circular collider (FCC). The HL-LHC has sensitivity to narrow Z ′ resonances consist..