"Figure 8b" of "Search for top quark partners with charge 5/3 in the same-sign dilepton and single-lepton final states in proton-proton collisions at $\sqrt{s} =$ 13 TeV"

Expected and observed limits at 95% CL for an RH $X_{5/3}$ after combining the same-sign dilepton and single-lepton final states. The theoretical uncertainty in the signal cross section is shown as a narrow band around the theoretical prediction.