Fig. 1.

Distribution of variables used for the signal region optimisation of the $2{\ell }^{\text{ss}}$ final state. The events are selected with the preselection requirements listed in Table 2. The data (dots) are compared with the predictions (histograms) that include the contributions from the dominant prompt-lepton background (WZ), other prompt-lepton backgrounds, processes where a fake lepton is reconstructed, and electrons with misidentified charge (QMisID). The expected signal distributions corresponding to two $H^{\pm \pm }$ masses are also shown, scaled up for visibility. The last bin includes overflows. In each figure the bottom panel shows the ratio of data to the prediction, where the band around unity represents the total uncertainty of the SM prediction