LHC di-lepton searches for Z' bosons which explain measurements of b → sl+l- transitions

Several current measurements of b -> sl(+)l(-) processes are in tension with Standard Model predictions, whereas others (e.g. R-K and R-K*) are in reasonable agreement with them. We examine some recent Z' models that fit the data as a whole appreciably better than does the Standard Model, confronting the models with ATLAS resonance searches in the e(+)e(-) and mu(+)mu(-) channels. The models are constrained by both channels; we find that the searches rule out less than one fifth of the allowed range of M. We estimate that the HL-LHC can roughly double the current sensitivity in My, but to cover the whole of the parameter space would take a more powerful machine, such as a 100 TeV pp collider.