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CMS-SUS-16-049 ; CERN-EP-2017-129

Search for direct production of supersymmetric partners of the top quark in the all-jets final state in proton-proton collisions at $ \sqrt{s} = $ 13 TeV

CMS Collaboration

10 July 2017

J. High Energy Phys. 10 (2017) 005

Abstract: A search for direct production of top squark pairs in events with jets and large transverse momentum imbalance is presented. The data are based on proton-proton collisions at a center-of-mass energy of 13 TeV, collected in 2016 at the CERN LHC, and correspond to an integrated luminosity of 35.9 fb$^{-1}$. The search considers a variety of $R$-parity conserving supersymmetric models, including ones for which the top squark and neutralino masses are nearly degenerate. Specialized jet reconstruction tools are developed to exploit the unique characteristics of the signal topologies. With no significant excess of events observed above the standard model expectations, upper limits are set on the direct top squark pair production cross section in the context of simplified supersymmetric models for various decay hypotheses. Models with larger differences in mass between the top squark and neutralino are probed for masses up to 1040 and 500 GeV, respectively, whereas models with a more compressed mass hierarchy are probed up to 660 and 610 GeV, respectively. The smallest mass difference probed is for masses near to 550 and 540 GeV, respectively.

Links: e-print arXiv:1707.03316 [hep-ex] (PDF) ; CDS record ; inSPIRE record ; CADI line (restricted) ;

Additional information on efficiencies needed for reinterpretation of these results are available here. Additional technical material can be found here

Figures
png pdf	Figure 1: Diagrams for the decay modes of pair-produced top squarks studied in this analysis. The decay cascades are denoted: (a) T2tt, (b) T2bW, (c) T2tb, (d) T2ttC, (e) T2bWC, and (f) T2cc. An asterisk indicates that the particle may be produced off-shell.
png pdf	Figure 2: Efficiencies in MC simulation for identifying the quark decays of top quarks (left), and W bosons (right), as a function of the $ {p_{\mathrm {T}}} $ of the generated top quarks or W bosons to which they were matched.
png pdf	Figure 2-a: Efficiencies in MC simulation for identifying the quark decays of top quarks, as a function of the $ {p_{\mathrm {T}}} $ of the generated top quarks or W bosons to which they were matched.
png pdf	Figure 2-b: Efficiencies in MC simulation for identifying the quark decays of W bosons, as a function of the $ {p_{\mathrm {T}}} $ of the generated top quarks or W bosons to which they were matched.
png pdf	Figure 3: Left: Efficiency in MC simulation to identify resolved top quark decays as a function of the $ {p_{\mathrm {T}}} $ of the generated top quark. Right: Misidentification rate in MC simulation as a function of the $ {p_{\mathrm {T}}} $ of resolved top quarks, in a sample dominated by the QCD multijet process.
png pdf	Figure 3-a: Efficiency in MC simulation to identify resolved top quark decays as a function of the $ {p_{\mathrm {T}}} $ of the generated top quark.
png pdf	Figure 3-b: Misidentification rate in MC simulation as a function of the $ {p_{\mathrm {T}}} $ of resolved top quarks, in a sample dominated by the QCD multijet process.
png pdf	Figure 4: Observed data and SM background predictions in the low-$ { {p_{\mathrm {T}}} ^\text {miss}}$ validation sample for the low $ {\Delta m} $ (left) and high $ {\Delta m} $ (right) selections. Ratios of the observed to SM predicted event counts derived from control regions are shown in the lower panel of each plot. The shaded blue band represents the statistical uncertainty combined with the systematic uncertainty resulting from the top quark and W boson tagging correction factors on the background prediction.
png pdf	Figure 4-a: Observed data and SM background predictions in the low-$ { {p_{\mathrm {T}}} ^\text {miss}}$ validation sample for the low $ {\Delta m} $ selection. Ratios of the observed to SM predicted event counts derived from control regions are shown in the lower panel. The shaded blue band represents the statistical uncertainty combined with the systematic uncertainty resulting from the top quark and W boson tagging correction factors on the background prediction.
png pdf	Figure 4-b: Observed data and SM background predictions in the low-$ { {p_{\mathrm {T}}} ^\text {miss}}$ validation sample for the high $ {\Delta m} $ selection. Ratios of the observed to SM predicted event counts derived from control regions are shown in the lower panel. The shaded blue band represents the statistical uncertainty combined with the systematic uncertainty resulting from the top quark and W boson tagging correction factors on the background prediction.
png pdf	Figure 5: Observed data events and SM background predictions for the low $ {\Delta m} $ search regions with $N_{\mathrm{ b } }=$ 0 (top), $N_{\mathrm{ b } }=$ 1 (middle), and $N_{\mathrm{ b } }\geq $ 2 (bottom). Ratios of the observed to SM predicted event counts are shown in the lower panel of each plot. The shaded blue band represents the combined statistical and systematic uncertainties on the SM predictions. The one SR for which the result is not visible in the lower panel is discussed in the text. Units are GeV.
png pdf	Figure 5-a: Observed data events and SM background predictions for the low $ {\Delta m} $ search regions with $N_{\mathrm{ b } }=$ 0. Ratios of the observed to SM predicted event counts are shown in the lower panel of each plot. The shaded blue band represents the combined statistical and systematic uncertainties on the SM predictions. The one SR for which the result is not visible in the lower panel is discussed in the text. Units are GeV.
png pdf	Figure 5-b: Observed data events and SM background predictions for the low $ {\Delta m} $ search regions with $N_{\mathrm{ b } }=$ 1. Ratios of the observed to SM predicted event counts are shown in the lower panel of each plot. The shaded blue band represents the combined statistical and systematic uncertainties on the SM predictions. The one SR for which the result is not visible in the lower panel is discussed in the text. Units are GeV.
png pdf	Figure 5-c: Observed data events and SM background predictions for the low $ {\Delta m} $ search regions with $N_{\mathrm{ b } }\geq $ 2. Ratios of the observed to SM predicted event counts are shown in the lower panel of each plot. The shaded blue band represents the combined statistical and systematic uncertainties on the SM predictions. The one SR for which the result is not visible in the lower panel is discussed in the text. Units are GeV.
png pdf	Figure 6: Observed data events and SM background predictions for the high $ {\Delta m} $ search regions. Details of the selection applied is displayed on each plot. Ratios of the observed to SM predicted event counts are shown in the lower panel of each plot. The shaded blue band represents the statistical and systematic uncertainty on the prediction. The one SR for which the result is not visible in the lower panel is discussed in the text. Units are GeV.
png pdf	Figure 6-a: Observed data events and SM background predictions for one the high $ {\Delta m} $ search regions. Details of the selection applied is displayed on the plot. Ratios of the observed to SM predicted event counts are shown in the lower panel. The shaded blue band represents the statistical and systematic uncertainty on the prediction. Units are GeV.
png pdf	Figure 6-b: Observed data events and SM background predictions for one the high $ {\Delta m} $ search regions. Details of the selection applied is displayed on the plot. Ratios of the observed to SM predicted event counts are shown in the lower panel. The shaded blue band represents the statistical and systematic uncertainty on the prediction. Units are GeV.
png pdf	Figure 6-c: Observed data events and SM background predictions for one the high $ {\Delta m} $ search regions. Details of the selection applied is displayed on the plot. Ratios of the observed to SM predicted event counts are shown in the lower panel. The shaded blue band represents the statistical and systematic uncertainty on the prediction. Units are GeV.
png pdf	Figure 6-d: Observed data events and SM background predictions for one the high $ {\Delta m} $ search regions. Details of the selection applied is displayed on the plot. Ratios of the observed to SM predicted event counts are shown in the lower panel. The shaded blue band represents the statistical and systematic uncertainty on the prediction. Units are GeV.
png pdf root	Figure 7: Exclusion limits at 95% CL for top squark pair production followed by the decay $\tilde{ \mathrm{ t } } _{1}\to \mathrm{ t } \tilde{\chi}^0_1 $ (T2tt), in the mass plane $m_{\tilde{\chi}^0_1 }$ versus $m_{\tilde{ \mathrm{ t } } _{1}}$. The areas to the left and below the solid black curves represent the observed exclusion and the $\pm $1 standard deviation contours for the NLO+NLL cross section calculations and their uncertainties [63]. The dashed red curves represent the corresponding expectation at 95% CL and $\pm $1 standard deviation contours for the associated experimental uncertainties. The "islands" represent regions that are not excluded by this search. The diagonal area where $ {\Delta m} $ is very close to the top quark mass, corresponding to a very light $ \tilde{\chi}^0_1 $, is left blank because the final states, which are similar to the SM ${\mathrm{ t } {}\mathrm{ \bar{t} } }$ background, have acceptance that varies strongly with $ \tilde{\chi}^0_1 $ mass, making it very difficult to model the signal acceptance in this region.
png pdf root	Figure 8: Exclusion limits at 95% CL for top squark pair production followed by the decay $\tilde{ \mathrm{ t } } _{1}\to \mathrm{ b } \tilde{\chi}^{\pm}_1 \to \mathrm{ b } \mathrm{ W } ^{\pm } \tilde{\chi}^0_1 $ (T2bW), in the mass plane $m_{\tilde{\chi}^0_1 }$ versus $m_{\tilde{ \mathrm{ t } } _{1}}$. The areas to the left and below the solid black curves represent the observed exclusion and the $\pm $1 standard deviation contours for the NLO+NLL cross section calculations and their uncertainties [63]. The dashed red curves represent the corresponding expectation at 95% CL and $\pm $1 standard deviation contours for the associated experimental uncertainties. In the lower left corner of the diagram, where $ {\Delta m} $ is close to the top quark mass, the sensitivity of the search is significantly reduced due to the fact that the $\tilde{ \mathrm{ t } } _{1}$ decay products are soft and often escape detection.
png pdf root	Figure 9: Exclusion limits at 95% CL for top squark pair production followed by the mixed decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } _{1}\overline{\tilde{\mathrm{t}}} _{1}\to \mathrm{ \bar{t} } \tilde{\chi}^0_1 \mathrm{ b } \tilde{\chi}^{+}_{1} $ (T2tb) decay scenario, in the mass plane $m_{\tilde{\chi}^0_1 }$ versus $m_{\tilde{ \mathrm{ t } } _{1}}$. In T2tb an assumption of a compressed mass spectrum in which the mass of $ \tilde{\chi}^{\pm}_1 $ is only 5 GeV greater than that of $ \tilde{\chi}^0_1 $, is considered. The areas to the left and below the solid black curves represent the observed exclusion and the $\pm $1 standard deviation contours for the NLO+NLL cross section calculations and their uncertainties [63]. The dashed red curves represent the corresponding expectation at 95% CL and $\pm $1 standard deviation contours for the associated experimental uncertainties. In the lower left corner of the diagram, where $ {\Delta m} $ is close to the top quark mass, the sensitivity of the search is significantly reduced due to the fact that the $\tilde{ \mathrm{ t } } _{1}$ decay products are soft and often escape detection.
png pdf root	Figure 10: Exclusion limits at 95% CL for top squark pair production followed by the four-body decay $\tilde{ \mathrm{ t } } _{1} \to \mathrm{ b } \mathrm {f} \bar{\mathrm {f'}} \tilde{\chi}^0_1 $ (T2ttC) in the mass plane $ {\Delta m}(\tilde{ \mathrm{ t } } _{1},\tilde{\chi}^0_1)$ versus $m_{\tilde{ \mathrm{ t } } _{1}}$. The areas to the left and below the solid black curves represent the observed exclusion and the $\pm $1 standard deviation contours for the NLO+NLL cross section calculations and their uncertainties [63]. The dashed red curves represent the corresponding expectation at 95% CL and $\pm $1 standard deviation contours for the associated experimental uncertainties.
png pdf root	Figure 11: Exclusion limits at 95% CL for top squark pair production followed by the decay $\tilde{ \mathrm{ t } } _{1}\to \mathrm{ b } \tilde{\chi}^{\pm}_1 \to \mathrm{ b } \mathrm {f} \bar{\mathrm {f'}} \tilde{\chi}^0_1 $ (T2bWC) in the mass plane $ {\Delta m}(\tilde{ \mathrm{ t } } _{1},\tilde{\chi}^0_1)$ versus $m_{\tilde{ \mathrm{ t } } _{1}}$. The areas to the left and below the solid black curves represent the observed exclusion and the $\pm $1 standard deviation contours for the NLO+NLL cross section calculations and their uncertainties [63]. The dashed red curves represent the corresponding expectation at 95% CL and $\pm $1 standard deviation contours for the associated experimental uncertainties.
png pdf root	Figure 12: Exclusion limits at 95% CL for top squark pair production followed by the decay $\tilde{ \mathrm{ t } } _{1}\to \mathrm{c} \tilde{\chi}^0_1 $ (T2cc) in the mass plane $ {\Delta m}(\tilde{ \mathrm{ t } } _{1},\tilde{\chi}^0_1)$ versus $m_{\tilde{ \mathrm{ t } } _{1}}$. The areas to the left and below the solid black curves represent the observed exclusion and the $\pm $1 standard deviation contours for the NLO+NLL cross section calculations and their uncertainties [63]. The dashed red curves represent the corresponding expectation at 95% CL and $\pm $1 standard deviation contours for the associated experimental uncertainties.

Tables
png pdf	Table 1: Summary of the 51 non-overlapping search regions that mainly target high $ {\Delta m} $ signal. The high $ {\Delta m} $ baseline selection is $N_{\text {j}}\geq $ 5, $ { {p_{\mathrm {T}}} ^\text {miss}} \geq $ 250 GeV, no leptons, $N_{\mathrm{ b } }\geq $ 1, and $\Delta \phi _{1234}\geq $ 0.5.
png pdf	Table 2: Summary of the 53 non-overlapping search regions that mainly target low $ {\Delta m} $ signal. The low $ {\Delta m} $ baseline selection is $N_{\text {j}}\geq $ 2, $ { {p_{\mathrm {T}}} ^\text {miss}} \geq $ 250 GeV, no leptons, $N_{\mathrm{ t } }=N_{\mathrm{ W } }=N_{\text {res}}= $ 0, $m_{\mathrm {T}}^{\mathrm {b}}< $ 175 GeV (when applicable), $ {| \Delta \phi (\mathrm {j}_1, {\vec{p}_{\mathrm {T}}^{\,\text {miss}}}) | } \geq $ 0.5, ${| \Delta \phi (\mathrm {j}_{2,3}, {\vec{p}_{\mathrm {T}}^{\,\text {miss}}}) | } \geq $ 0.15, and an ISR jet with $p_{\mathrm {T}}^{\mathrm {ISR}}\geq $ 300 GeV, $ {| \eta | } \leq $ 2.4, $ {| \Delta \phi (j_{\text {ISR}}, {\vec{p}_{\mathrm {T}}^{\,\text {miss}}}) | } \geq $ 2, and $ {S_{E_{\mathrm {T}}} } \geq $10 $\sqrt{} $GeV.
png pdf	Table 3: Summary of the validation region selections. The top part of the table (rows 0-14) corresponds to regions for the low $ {\Delta m} $ selections, whereas the bottom part (rows 15-31) corresponds to regions for the high $ {\Delta m} $ selections.
png pdf	Table 4: Range of systematic uncertainties [%] in the prediction across the different search regions. "Rare" column includes diboson and ${{\mathrm{ t } {}\mathrm{ \bar{t} } } \mathrm{Z}} $ processes. "Signal" column shows the range of systematic uncertainties representative of the full set of models shown in Fig. xxxxx.
png pdf	Table 5: Predicted background yields and the observation in different search regions for the low $ {\Delta m} $ analysis. The total uncertainty is given for each background prediction.
png pdf	Table 6: Predicted background yields and the observation in different search regions for the high $ {\Delta m} $ analysis. The total uncertainty is given for each background prediction.

Summary

A search is presented for direct top squark pair production in the all-jets final states based upon data collected with the CMS detector in pp collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. The search is optimized for discovery through a variety of signatures. No significant excess of events is observed beyond the expected contribution from SM processes, and exclusion limits are set at a 95% confidence level in the context of simplified models [46,47,48] of direct top squark pair production. In the parameter space of large mass differences between the $\tilde{ \mathrm{ t } }_{1}$ and $\tilde{\chi}^0_1$ that permit the $\tilde{ \mathrm{ t } }_{1}$ to decay to an on-shell top quark and a neutralino, top squark masses up to 1040 GeV and $\tilde{\chi}^0_1$ masses up to 500 GeV are excluded. Alternatively, when the top squark decays to a bottom quark and a $\tilde{\chi}^{\pm}_1$, $\tilde{ \mathrm{ t } }_{1}$ masses up to 800 GeV and $\tilde{\chi}^0_1$ masses up to 360 GeV are excluded. Finally, for possibilities in which the branching fractions for these two top squark decay modes equal 50%, including the assumption of a compressed mass spectrum with the mass of the $ \tilde{\chi}^{\pm}_1 $ only 5 GeV greater than that of $ \tilde{\chi}^0_1 $, top squark masses up to 940 GeV and $\tilde{\chi}^0_1$ masses up to 440 GeV are excluded. In the regions of parameter space where the mass difference between the $\tilde{ \mathrm{ t } }_{1}$ and $\tilde{\chi}^0_1$ is smaller than the mass of the W boson, we consider four-body decays of top squarks in which top squark masses up to 580 GeV are excluded for a neutralino mass of 540 GeV. An additional decay that is relevant in this parameter space is one in which the top squark decays to a bottom quark and a $\tilde{\chi}^{\pm}_1$, that then decays to a virtual W boson and a $ \tilde{\chi}^0_1 $. Here, top squark masses up to 660 GeV are excluded for a neutralino mass of 610 GeV. Finally, we consider decays through a flavor changing neutral current process where the $\tilde{ \mathrm{ t } }_{1}$ decays to a c quark and a $ \tilde{\chi}^0_1 $. In this case, $\tilde{ \mathrm{ t } }_{1}$ and $ \tilde{\chi}^0_1 $ masses up to 560 GeV and up to 520 GeV, respectively, are excluded. In summary, we present a search that takes advantage of a large new set of data collected by the CMS experiment in 2016, as well as a variety of new methods that yield exclusion limits for a wide array of top squark decay modes in planes of $m_{\tilde{\chi}^0_1}$ versus $m_{\tilde{ \mathrm{ t } }_{1}}$ and $m_{\tilde{ \mathrm{ t } }_{1}} - m_{\tilde{\chi}^0_1}$ versus $m_{\tilde{ \mathrm{ t } }_{1}}$ that extend significantly beyond those obtained in previous searches.

Additional Figures
png pdf	Additional Figure 1: Expected significances for simplified models of top squark pair production in the pure $\tilde{ \mathrm{ t } } _{1}\to \mathrm{ t } \tilde{\chi}^0_1 $ ("T2tt") decay scenario.
png pdf	Additional Figure 2: Observed significances for simplified models of top squark pair production in the pure $\tilde{ \mathrm{ t } } _{1}\to \mathrm{ t } \tilde{\chi}^0_1 $ ("T2tt") decay scenario.
png pdf	Additional Figure 3: Expected significances for simplified models of top squark pair production in the pure $\tilde{ \mathrm{ t } } _{1}\to \mathrm{ b } \tilde{\chi}^{\pm}_1 \rightarrow \mathrm{ b } {\mathrm {W}}^{\pm } \tilde{\chi}^0_1 $ ("T2bW'') decay scenario.
png pdf	Additional Figure 4: Observed significances for simplified models of top squark pair production in the pure $\tilde{ \mathrm{ t } } _{1}\to \mathrm{ b } \tilde{\chi}^{\pm}_1 \rightarrow \mathrm{ b } {\mathrm {W}}^{\pm } \tilde{\chi}^0_1 $ ("T2bW'') decay scenario.
png pdf	Additional Figure 5: Expected significances for simplified models of top squark pair production in the $\mathrm{ p } \mathrm{ p } \rightarrow \tilde{ \mathrm{ t } } _{1}\overline{\tilde{\mathrm{t}}} _{1}\rightarrow \mathrm{ \bar{t} } \tilde{\chi}^0_1 \mathrm{ b } \tilde{\chi}^{+}_{1} $ ("T2tb'') decay scenario, under the assumption of a compressed mass spectrum in which the mass of $ \tilde{\chi}^{\pm}_1 $ is only 5 GeV greater than that of $ \tilde{\chi}^0_1 $.
png pdf	Additional Figure 6: Observed significances for simplified models of top squark pair production in the $\mathrm{ p } \mathrm{ p } \rightarrow \tilde{ \mathrm{ t } } _{1}\overline{\tilde{\mathrm{t}}} _{1}\rightarrow \mathrm{ \bar{t} } \tilde{\chi}^0_1 \mathrm{ b } \tilde{\chi}^{+}_{1} $ ("T2tb'') decay scenario, under the assumption of a compressed mass spectrum in which the mass of $ \tilde{\chi}^{\pm}_1 $ is only 5 GeV greater than that of $ \tilde{\chi}^0_1 $.
png pdf	Additional Figure 7: Expected significances for simplified models of top squark pair production in the $\tilde{ \mathrm{ t } } _{1} \to \mathrm{ b } \mathrm {f} \bar{\mathrm {f'}} \tilde{\chi}^0_1 $ ("T2ttC'') four-body decay scenario.
png pdf	Additional Figure 8: Observed significances for simplified models of top squark pair production in the $\tilde{ \mathrm{ t } } _{1} \to \mathrm{ b } \mathrm {f} \bar{\mathrm {f'}} \tilde{\chi}^0_1 $ ("T2ttC'') four-body decay scenario.
png pdf	Additional Figure 9: Expected significances for simplified models of top squark pair production in the $\tilde{ \mathrm{ t } } _{1}\to \mathrm{ b } \tilde{\chi}^{\pm}_1 \to \mathrm{ b } \mathrm {f} \bar{\mathrm {f'}} \tilde{\chi}^0_1 $ ("T2bWC") four-body decay scenario.
png pdf	Additional Figure 10: Observed significances for simplified models of top squark pair production in the $\tilde{ \mathrm{ t } } _{1}\to \mathrm{ b } \tilde{\chi}^{\pm}_1 \to \mathrm{ b } \mathrm {f} \bar{\mathrm {f'}} \tilde{\chi}^0_1 $ ("T2bWC") four-body decay scenario.
png pdf	Additional Figure 11: Expected significances for simplified models of top squark pair production in the $\tilde{ \mathrm{ t } } _{1}\to \mathrm{c} \tilde{\chi}^0_1 $ ("T2cc") decay scenario.
png pdf	Additional Figure 12: Observed significances for simplified models of top squark pair production in the $\tilde{ \mathrm{ t } } _{1}\to \mathrm{c} \tilde{\chi}^0_1 $ ("T2cc") decay scenario.
png pdf	Additional Figure 13: BDT efficiency of merged top tagging for reinterpretation objects. See reinterpretation material.
png pdf	Additional Figure 14: BDT efficiency of merged top misidentification rate for reinterpretation objects. See reinterpretation material.
png pdf	Additional Figure 15: BDT efficiency of merged W tagging for reinterpretation objects. See reinterpretation material.
png pdf	Additional Figure 16: BDT efficiency of merged W misidentification rate for reinterpretation objects. See reinterpretation material.
png pdf	Additional Figure 17: BDT efficiency of resolved top tagging for reinterpretation objects. See reinterpretation material.
png pdf	Additional Figure 18: BDT efficiency of resolved top misidentification rate for reinterpretation objects. See reinterpretation material.
png pdf	Additional Figure 19: Observed events and SM estimates for the super search regions defined for the low $ {\Delta m} $ category. The ratios of the observed data to the SM prediction derived from control regions (black points, with error bars corresponding to the data statistical uncertainty) are shown in the ratio plots. The shaded blue band represents the statistical and systematic uncertainty on the background prediction. The units of $ { {p_{\mathrm {T}}} ^{\mathrm {b}}}$ and $m_{\mathrm {T}}^{\mathrm {b}}$ are GeV, where applicable.
png pdf	Additional Figure 20: Observed events and SM estimates for the super search regions defined for the high $ {\Delta m} $ category. The ratios of the observed data to the SM prediction derived from control regions (black points, with error bars corresponding to the data statistical uncertainty) are shown in the ratio plots. The shaded blue band represents the statistical and systematic uncertainty on the background prediction. The units of $ { {p_{\mathrm {T}}} ^{\mathrm {b}}}$ and $m_{\mathrm {T}}^{\mathrm {b}}$ are GeV, where applicable.
png pdf root	Additional Figure 21: Correlation matrix of the background estimates between the 26 super search regions.
png pdf root	Additional Figure 22: Covariance matrix of the background estimates between the 26 super search regions.
png pdf	Additional Figure 23: Summary of the limits obtained in the search.
png pdf	Additional Figure 24: Cross section limits and exclusion region for the T2ttC model in the top squark vs. LSP mass plane.
png pdf	Additional Figure 25: Cross section limits and exclusion region for the T2bWC model in the top squark vs. LSP mass plane.
png pdf	Additional Figure 26: Cross section limits and exclusion region for the T2cc model in the top squark vs. LSP mass plane.

Additional Tables
png pdf	Additional Table 1: Event yields from simulation, followed by the total selection efficiency with respect to the first row, after applying the sequential selections composing the low and high $ {\Delta m} $ baseline selections. The offline trigger selection is firstly applied, followed by the lepton vetoes. Next, the high $ {\Delta m} $ baseline selections are applied sequentially starting after the lepton vetoes. Finally, the low $ {\Delta m} $ baseline selections are applied sequentially but starting again just after the lepton vetoes. The expected yields of three signal benchmark points are included. The numbers are normalized to an integrated luminosity of 35.9 fb$^{-1}$ and the uncertainties correspond to statistical uncertainty from the MC samples.
png pdf	Additional Table 2: Predicted acceptance times efficiency in the super search regions of the low $ {\Delta m} $ category for the T2ttC(500,450) signal benchmark point. The first column corresponds to the top and W objects used in the analysis; the second corresponds to the simplified top and W objects defined in the reinterpretation material.
png pdf	Additional Table 3: Predicted acceptance times efficiency in the super search regions of the high $ {\Delta m} $ category for the T2tt(850,100) signal benchmark point. The first column corresponds to the top and W objects used in the analysis; the second corresponds to the simplified top and W objects defined in the reinterpretation material.
png pdf	Additional Table 4: Summary of the 10 disjoint super search regions in the low $ {\Delta m} $ category. The low $ {\Delta m} $ baseline selection is $N_{\text {j}}\geq 2$, $ { {p_{\mathrm {T}}} ^\text {miss}} >250 GeV $, zero leptons, $N_{\mathrm{ t } }=N_{ {\mathrm {W}}}=N_{\text {res}}=0$, $N_{\mathrm{ b } }\geq 0$, $m_{\mathrm {T}}^{\mathrm {b}}<175 GeV $ (when applicable), $|\Delta \phi (\text {j}_1, {E_{\mathrm {T}}})|>0.5, |\Delta \phi (\text {j}_{2,3}, {E_{\mathrm {T}}})| > 0.15$, $ {p_{\mathrm {T}}} (\text {ISR}) > 300$ GeV, $ |\eta (\text {ISR})| < 2.4$, $|\Delta \phi (j_{\text {ISR}}, { {p_{\mathrm {T}}} ^\text {miss}})|>2$, and $ {S_{E_{\mathrm {T}}\hspace {-0.8em}/\kern 0.45em} }> 10 GeV ^{1/2}$.
png pdf	Additional Table 5: Summary of the 16 disjoint super search regions in the high $ {\Delta m} $ category. The high $ {\Delta m} $ baseline selection is $N_{\text {j}}\geq 5$, $ { {p_{\mathrm {T}}} ^\text {miss}} >250 GeV $, zero leptons, $N_{\mathrm{ b } }\geq 1$, and $\Delta \phi _{1234}>0.5$.
png pdf	Additional Table 6: Predicted background yields and the observation in the super search regions of the low $ {\Delta m} $ category. The total uncertainty is given for each background prediction.
png pdf	Additional Table 7: Predicted background yields and the observation in the super search regions of the high $ {\Delta m} $ category. The total uncertainty is given for each background prediction.

Additional material and instructions needed for reinterpretation here.

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26	ATLAS Collaboration	Search for direct top squark pair production in final states with one isolated lepton, jets, and missing transverse momentum in $ \sqrt{s}=$ 7 TeV $ \mathrm{ p }\mathrm{ p } $ collisions using 4.7 fb$^{-1} $ of ATLAS data	PRL 109 (2012) 211803	1208.2590
27	ATLAS Collaboration	Search for a heavy top-quark partner in final states with two leptons with the ATLAS detector at the LHC	JHEP 11 (2012) 094	1209.4186
28	ATLAS Collaboration	Search for direct top-squark pair production in final states with two leptons in $ \mathrm{ p }\mathrm{ p } $ collisions at $ \sqrt{s}=$ 8 TeV with the ATLAS detector	JHEP 06 (2014) 124	1403.4853
29	ATLAS Collaboration	Search for direct third-generation squark pair production in final states with missing transverse momentum and two b-jets in $ \sqrt{s}=$ 8 TeV $ \mathrm{ p }\mathrm{ p } $ collisions with the ATLAS detector	JHEP 10 (2013) 189	1308.2631
30	ATLAS Collaboration	Measurement of spin correlation in top-antitop quark events and search for top squark pair production in pp collisions at $ \sqrt{s}=$ 8 TeV using the ATLAS detector	PRL 114 (2015) 142001	1412.4742
31	ATLAS Collaboration	Search for pair-produced third-generation squarks decaying via charm quarks or in compressed supersymmetric scenarios in $ \mathrm{ p }\mathrm{ p } $ collisions at $ \sqrt{s}=$ 8 TeV with the ATLAS detector	PRD 90 (2014) 052008	1407.0608
32	ATLAS Collaboration	ATLAS Run 1 searches for direct pair production of third-generation squarks at the Large Hadron Collider	EPJC 75 (2015) 510	1506.08616
33	CMS Collaboration	Search for top-squark pair production in the single-lepton final state in $ \mathrm{ p }\mathrm{ p } $ collisions at $ \sqrt{s} = $ 8 TeV	EPJC 73 (2013) 2677	CMS-SUS-13-011 1308.1586
34	CMS Collaboration	Search for supersymmetry in hadronic final states with missing transverse energy using the variables $ \alpha_\mathrm{T} $ and b-quark multiplicity in pp~collisions at $ \sqrt{s} = $ 8 TeV	EPJC 73 (2013) 2568	CMS-SUS-12-028 1303.2985
35	CMS Collaboration	Search for supersymmetry using razor variables in events with b-tagged jets in $ \mathrm{ p }\mathrm{ p } $ collisions at $ \sqrt{s} = $ 8 TeV	PRD 91 (2015) 052018	CMS-SUS-13-004 1502.00300
36	CMS Collaboration	Searches for third-generation squark production in fully hadronic final states in proton-proton collisions at $ \sqrt{s} = $ 8 TeV	JHEP 06 (2015) 116	CMS-SUS-14-001 1503.08037
37	CMS Collaboration	Search for direct pair production of supersymmetric top quarks decaying to all-hadronic final states in $ \mathrm{ p }\mathrm{ p } $ collisions at $ \sqrt{s} = $ 8 TeV	EPJC 76 (2016) 460	CMS-SUS-13-023 1603.00765
38	ATLAS Collaboration	Search for top squarks in final states with one isolated lepton, jets, and missing transverse momentum in $ \sqrt{s}=$ 13 TeV $ \mathrm{ p }\mathrm{ p } $ collisions with the ATLAS detector	PRD 94 (2016) 052009	1606.03903
39	CMS Collaboration	Search for new physics with the M$ _{T2} $ variable in all-jets final states produced in $ \mathrm{ p }\mathrm{ p } $ collisions at $ \sqrt{s}=$ 13 TeV	JHEP 10 (2016) 006	CMS-SUS-15-003 1603.04053
40	CMS Collaboration	Inclusive search for supersymmetry using razor variables in $ \mathrm{ p }\mathrm{ p } $ collisions at $ \sqrt{s} = $ 13 TeV	PRD 95 (2017) 012003	CMS-SUS-15-004 1609.07658
41	CMS Collaboration	A search for new phenomena in pp collisions at $ \sqrt{s} = $ 13 TeV in final states with missing transverse momentum and at least one jet using the $ \alpha _{\mathrm {T}} $ variable	EPJC 77 (2017) 294	CMS-SUS-15-005 1611.00338
42	CMS Collaboration	Searches for pair production of third-generation squarks in $ \sqrt{s} = $ 13 TeV pp collisions	EPJC 77 (2017) 327	CMS-SUS-16-008 1612.03877
43	ATLAS Collaboration	Search for direct top squark pair production in events with a Higgs or $ Z $ boson, and missing transverse momentum in $ \sqrt{s}=$ 13 TeV $ pp $ collisions with the ATLAS detector	Submitted to JHEP	1706.03986
44	CMS Collaboration	Search for supersymmetry in multijet events with missing transverse momentum in proton-proton collisions at 13 TeV	Submitted to PRD	CMS-SUS-16-033 1704.07781
45	CMS Collaboration	Search for new phenomena with the $ M_{\text{T}2} $ variable in the all-hadronic final state produced in proton-proton collisions at $ \sqrt{s} = $ 13 TeV	Submitted to EPJC	CMS-SUS-16-036 1705.04650
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88	J. Thaler and K. Van Tilburg	Maximizing boosted top identification by minimizing N-subjettiness	JHEP 02 (2012) 093	1108.2701
89	CMS Collaboration	Performance of quark/gluon discrimination in 8 TeV pp data	CMS-PAS-JME-13-002	CMS-PAS-JME-13-002
90	H. Voss, A. Hocker, J. Stelzer, and F. Tegenfeldt	TMVA, the toolkit for multivariate data analysis with ROOT	in XIth International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT) 2007	physics/0703039
91	CMS Collaboration	Jet algorithms performance in 13 TeV data	CMS-PAS-JME-16-003	CMS-PAS-JME-16-003
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97	CMS Collaboration	Measurement of the WZ production cross section in $ \mathrm{ p }\mathrm{ p } $ collisions at $ \sqrt{s}=$ 13 TeV	PLB 766 (2017) 268	CMS-SMP-16-002 1607.06943
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100	CMS Collaboration	CMS luminosity measurements for the 2016 data taking period	CMS-PAS-LUM-17-001	CMS-PAS-LUM-17-001
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103	ATLAS and CMS Collaborations	Procedure for the LHC Higgs boson search combination in summer 2011	ATL-PHYS-PUB-2011-011, CMS NOTE-2011/005
104	G. Cowan, K. Cranmer, E. Gross, and O. Vitells	Asymptotic formulae for likelihood-based tests of new physics	EPJC 71 (2011) 1554	1007.1727
105	R. Grober, M. M. Mohlleitner, E. Popenda, and A. Wlotzka	Light stop decays: implications for LHC searches	EPJC 75 (2015) 420	1408.4662

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