"Figure 2" of "Search for a new heavy resonance decaying to a top quark and a neutral scalar boson in proton-proton collisions at $\sqrt{s}$ = 13 TeV"

The upper limit at 95% CL on the product of cross section for the $\mathrm{T}^{\prime} \to \mathrm{t}\phi$ process and branching fraction $\mathcal{B}(\mathrm{t} \to \mathrm{bq}\bar{\mathrm{q}}^\prime)$ as a function of $(\mathrm{T}^{\prime}, \mathit{m}_{\phi})$, assuming $\mathcal{B}(\phi \to \mathrm{b}\bar{\mathrm{b}})$=100%. Masses of the $\phi$ boson below 75 GeV are exclusive to the semileptonic channel, while $\mathit{m}_{\phi}>250$ are exclusive to the fully hadronic channel. Besides $\mathit{m}_{\phi} = 225$ GeV, also exclusive to the fully hadronic channel, upper limits for $75 < \mathit{m}_{\phi} < 250$ GeV are obtained from the combination of the two channels. Gaps in $\mathit{m}_{\phi}$ above 250 GeV are due to the limitations in the signal interpolation scheme in the hadronic channel, while gaps in $\mathit{m}_{\phi} < 250$ GeV correspond to signals not considered by the semileptonic channel due to poor signal efficiency.