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Relative systematic uncertainties in the background estimate for the high-mass analysis. The individual uncertainties can be correlated, such that the total background uncertainty is not necessarily their sum in quadrature.

Breakdown of relative uncertainties in background model in the low-mass analysis. Uncertainties below 0.5\% are not shown but are used in the fit.

The division of signal, control, and validation regions using the $m(h_1)$ and $m(h_2)$ variables in the high-mass analysis.

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: : Distribution of \met in the control region (a) before and (b) after the BDT reweighting is applied.

Distributions of $m(h_1)$ (top) and \meffb (bottom) for events passing the preselection criteria of the high-mass analysis. All backgrounds (including $\ttbar$) are normalized using the best available theoretical calculation described in Section~\ref{sec:samples}. The dashed histograms show the distributions of the variables for selected signal models at the best available theoretical cross section. The statistical and experimental systematic uncertainties (as defined in Section~\ref{sec:syst_high}) are included in the uncertainty band. The last bin includes overflows.

Diagram for the simplified model considered in the analysis. The production of the \hino\ occurs via mass-degenerate pairs of charginos or neutralinos, which decay to the \ninoone\ and immeasurably low momentum particles.

Distributions of $m(h_1)$ (top) and \meffb (bottom) for events passing the preselection criteria of the high-mass analysis. All backgrounds (including $\ttbar$) are normalized using the best available theoretical calculation described in Section~\ref{sec:samples}. The dashed histograms show the distributions of the variables for selected signal models at the best available theoretical cross section. The statistical and experimental systematic uncertainties (as defined in Section~\ref{sec:syst_high}) are included in the uncertainty band. The last bin includes overflows.

Event yields in control regions and related \ttbar\ normalization factors after the background-only fit for the high-mass analysis. The upper panel shows the observed number of events and the predicted background yield before the fit. All uncertainties described in Section \ref{sec:syst_high} are included in the uncertainty band. The background category $\ttbar+X$ includes $\ttbar W/Z$, $\ttbar H$, and $\ttbar \ttbar$ events. The $\ttbar$ normalization is obtained from the fit and is displayed in the bottom panel.

The unrolled distribution of \met and \meffb for data and background in validation region 1 of the low-mass analysis. The bottom panel shows the significance of any disagreement between the data and the background model~\cite{Choudalakis2012}. All systematic uncertainties described in Section~\ref{sec:syst_low} are included.

Results of the background only fit extrapolated to the SRs of the high-mass analysis. The $\ttbar$ normalization is obtained from the fit to the CRs shown in Figure~\ref{fig:pullCR}. The data in the SRs are not included in the fit. The upper panel shows the observed number of events and the predicted background yield. The bottom panel shows the significance of any disagreement between the data and the background model~\cite{Choudalakis2012}. All uncertainties defined in Section~\ref{sec:syst_high} are included in the uncertainty band. The background category $\ttbar+X$ includes $\ttbar W/Z$, $\ttbar H$, and $\ttbar \ttbar$ events.

The unrolled distribution of \met and \meffb for data and background in the control region of the low-mass analysis. The bottom panel shows the significance of any disagreement between the data and the background model. Only the statistical and non-closure uncertainties, described in Section~\ref{sec:syst_low}, are shown.

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The unrolled distribution of \met and \meffb for data and background in validation region 2 of the low-mass analysis. The bottom panel shows the significance of any disagreement between the data and the background model~\cite{Choudalakis2012}. All systematic uncertainties described in Section~\ref{sec:syst_low} are included.

The unrolled distribution of \met and \meffb for data, background and an example signal sample in the signal region of the low-mass analysis. The bottom panel shows the significance of any disagreement between the data and the background model~\cite{Choudalakis2012}. All systematic uncertainties described in Section~\ref{sec:syst_low} are included. The dashed line includes the signal contribution and defines the significance as signal/$\sigma$.

Results of the background-only fit extrapolated to the VRs of the high-mass analysis. The $\ttbar$ normalization is obtained from the fit to the CRs shown in Figure~\ref{fig:pullCR}. The upper panel shows the observed number of events and the predicted background yield. The bottom panel shows the significance of any disagreement between the data and the background model~\cite{Choudalakis2012}. All uncertainties defined in Section~\ref{sec:syst_high} are included in the uncertainty band. The background category $\ttbar+X$ includes $\ttbar W/Z$, $\ttbar H$, and $\ttbar \ttbar$ events.

: : Exclusion limits on \hino\ pair production. In both interpretations, the results of the low-mass analysis are used below $\mhino = 300$ GeV, while those of the high-mass analysis are used above. In all cases the \gravino is assumed to be nearly massless. The figure shows (a) the observed (solid) vs expected (dashed) 95\% upper limits on the \hino\ pair production cross-section as a function of \mhino. The 1$\sigma$ and 2$\sigma$ uncertainty bands on the expected limit are shown as green and yellow, respectively. The theory cross-section and its uncertainty are shown in the solid and shaded red curve. The bottom panel shows the ratio of the observed and expected limits with the theory cross-section. The figure also shows (b) the observed (solid) vs expected (dashed) 95\% limits in the \mhino\ vs $B(\hino\rightarrow h \tilde{G})$ plane, where $B(\hino\rightarrow h \tilde{G})$ denotes the branching ratio for the decay $\hino \rightarrow h \gravino$. The 1$\sigma$ uncertainty band is overlaid in green and the 2$\sigma$ in yellow. The regions above the lines are excluded by the analyses.

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: : The distribution of $m_{2j}^\textrm{lead}$ versus $m_{2j}^\textrm{subl}$ for (a) the 4-tag data, and (b) the 2-tag data used to model the background. The region definitions are superimposed.