"Figure 6a" of "Search for charged Higgs bosons decaying into top and bottom quarks in lepton+jets final states in proton-proton collisions at $\sqrt{s}$ = 13 TeV"

Observed and expected 95% CL limits on the cross section times branching ratio for different $H^{\pm}$ mass hypotheses with $ρ_{tc} = 0.4$, $ρ_{tt} = 0.6$ . The inner (green) band and the outer (yellow) band represent the regions containing 68% and 95%, respectively, of the distribution of limits expected under the background-only hypothesis. Theoretical prediction with different $ρ_{tc}$ and $ρ_{tt}$ couplingsare shown with the grey bands representing the corresponding uncertainties due to the factorization and renormalization scales and the PDFs.