Finally, we subdivide events in each and [$\Sigma\mT$]{}region into the categories ${\ensuremath{N_{\text{j}}}\xspace}= 0$ and ${\ensuremath{N_{\text{j}}}\xspace}\geq 1$. This binning is beneficial as background events passing the SR kinematic selections are largely characterized by additional jet activity, while signal contains very few additional jets. The 0-jet category therefore provides nearly background-free SRs. However, we retain the SRs with ${\ensuremath{N_{\text{j}}}\xspace}\geq 1$ that are also expected to contain signal events with ISR or pileup jets.

\[tab:sr\]

  -------------------------- -- --- --------- --- --------- --- --------- -- --- --------- --- --------- --- --------- --
                                                                                                                       
  \[\] [$\Sigma\mT$]{}\[\]                                                                                             
  \[\] [$N_{\text{j}}$]{}        0   $\geq$1   0   $\geq$1   0   $\geq$1      0   $\geq$1   0   $\geq$1   0   $\geq$1  
  -------------------------- -- --- --------- --- --------- --- --------- -- --- --------- --- --------- --- --------- --

![\[fig:srvariables\_tautau\] Distributions in [$\Sigma\mT$]{}() and () for events in the combined 2016 and 2017 data sets passing the baseline selection in the [$\tauh\tauh$]{}final state, along with the corresponding prediction for the SM background and three benchmark models for [$\PSGt_{\mathrm{L}}$]{}pair production with $m({\ensuremath{\PSGt_{\mathrm{L}}}\xspace})=100$, 125, and 200, $m(\PSGczDo)=1\GeV$. The numbers within parentheses in the legend correspond to the masses of the [$\PSGt_{\mathrm{L}}$]{}and in . The last bin includes overflow events in each case. The shaded uncertainty bands represent the combined statistical and 