Table 7.

Results in the on-Z SRs (SR-Z). The flavour symmetric, $Z/{\mathit{\gamma }}^{\ast }+\text{jets}$ and fake-lepton background components are all derived using data-driven estimates described in the text. All other backgrounds are taken from MC simulation. The displayed uncertainties include the statistical and systematic uncertainty components combined

Channel	SR-Z ee	SR-Z $\mathit{\mu }\mathit{\mu }$	SR-Z same-flavour combined
Observed events	16	13	29
Expected background events	$4.2\pm 1.6$	$6.4\pm 2.2$	$10.6\pm 3.2$
Flavour-symmetric backgrounds	$2.8\pm 1.4$	$3.3\pm 1.6$	$6.0\pm 2.6$
$Z/{\mathit{\gamma }}^{\ast }+\text{jets}$ (jet-smearing)	$0.05\pm 0.04$	$0.{02}_{-0.02}^{+0.03}$	$0.07\pm 0.05$
Rare top	$0.18\pm 0.06$	$0.17\pm 0.06$	$0.35\pm 0.12$
WZ/ZZ diboson	$1.2\pm 0.5$	$1.7\pm 0.6$	$2.9\pm 1.0$
Fake leptons	$0.1_{-0.1}^{+0.7}$	$1.2_{-1.2}^{+1.3}$	$1.3_{-1.3}^{+1.7}$