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CMS-SUS-16-034 ; CERN-EP-2017-170

Search for new phenomena in final states with two opposite-charge, same-flavor leptons, jets, and missing transverse momentum in pp collisions at $\sqrt{s} = $ 13 TeV

CMS Collaboration

26 September 2017

JHEP 03 (2018) 076

Abstract: Search results are presented for physics beyond the standard model in final states with two opposite-charge, same-flavor leptons, jets, and missing transverse momentum. The data sample corresponds to an integrated luminosity of 35.9 fb$^{-1}$ of proton-proton collisions at $\sqrt{s} = $ 13 TeV collected with the CMS detector at the LHC in 2016. The analysis uses the invariant mass of the lepton pair, searching for a kinematic edge or a resonant-like excess compatible with the Z boson mass. The search for a kinematic edge targets production of particles sensitive to the strong force, while the resonance search targets both strongly and electroweakly produced new physics. The observed yields are consistent with the expectations from the standard model, and the results are interpreted in the context of simplified models of supersymmetry. In a gauge mediated supersymmetry breaking (GMSB) model of gluino pair production with decay chains including Z bosons, gluino masses up to 1500-1770 GeV are excluded at the 95% confidence level depending on the lightest neutralino mass. In a model of electroweak chargino-neutralino production, chargino masses as high as 610 GeV are excluded when the lightest neutralino is massless. In GMSB models of electroweak neutralino-neutralino production, neutralino masses up to 500-650 GeV are excluded depending on the decay mode assumed. Finally, in a model with bottom squark pair production and decay chains resulting in a kinematic edge in the dilepton invariant mass distribution, bottom squark masses up to 980-1200 GeV are excluded depending on the mass of the next-to-lightest neutralino.

Links: e-print arXiv:1709.08908 [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 for CMS speakers can be found here.

Figures
png pdf	Figure 1: Diagrams for models with decays containing at least one dilepton pair stemming from an on-shell Z boson decay studied in this analysis. The model targeted by the strong-production search is shown in the upper left. The three other diagrams correspond to EW production of chargino-neutralino or neutralino-neutralino pairs. All the diagrams containing a gravitino ($ \tilde{\mathrm{G}} $) represent gauge-mediated SUSY breaking (GMSB) models.
png pdf	Figure 1-a: Diagram corresponding to the strong-production search: gauge-mediated SUSY breaking (GMSB) model. At least one dilepton pair stems from an on-shell Z boson decay.
png pdf	Figure 1-b: Diagram corresponding to the EW production of a chargino-neutralino pair search. One dilepton pair stems from the on-shell Z boson decay.
png pdf	Figure 1-c: Diagram corresponding to the EW production of a neutralino-neutralino pair search: gauge-mediated SUSY breaking (GMSB) model. At least one dilepton pair stems from an on-shell Z boson decay.
png pdf	Figure 1-d: Diagram corresponding to the EW production of a neutralino-neutralino pair search: gauge-mediated SUSY breaking (GMSB) model. One dilepton pair stems from the on-shell Z boson decay.
png pdf	Figure 2: Diagram showing a possible decay chain in the slepton edge model. Bottom squarks are pair produced with subsequent decays that frequently contain dilepton pairs. This model features a characteristic edge in the $ {m_{\ell \ell}} $ spectrum given approximately by the mass difference between the $ \tilde{\chi}^0_2 $ and $ \tilde{\chi}^0_1 $ particles.
png pdf	Figure 3: The $ {{p_{\mathrm {T}}} ^\text {miss}} $ distribution is shown for data compared to the background prediction in the on-Z strong-production SRs with no b-tagged jets (left) and at least 1 b-tagged jet (right). The rows show SRA (upper), SRB (middle), and SRC (lower). The lower panel of each plot shows the ratio of observed data to the predicted value in each bin. The hashed band in the upper panels shows the total uncertainty in the background prediction, including statistical and systematic components. The $ {{p_{\mathrm {T}}} ^\text {miss}} $ template prediction for each SR is normalized to the first bin of each distribution, and therefore the prediction agrees with the data by construction.
png pdf	Figure 3-a: The $ {{p_{\mathrm {T}}} ^\text {miss}} $ distribution is shown for data compared to the background prediction in the on-Z strong-production SRA signal region, with no b-tagged jet. The lower panel shows the ratio of observed data to the predicted value in each bin. The hashed band in the upper panel shows the total uncertainty in the background prediction, including statistical and systematic components. The $ {{p_{\mathrm {T}}} ^\text {miss}} $ template prediction is normalized to the first bin of the distribution, and therefore the prediction agrees with the data by construction.
png pdf	Figure 3-b: The $ {{p_{\mathrm {T}}} ^\text {miss}} $ distribution is shown for data compared to the background prediction in the on-Z strong-production SRA signal region, with at least 1 b-tagged jet. The lower panel shows the ratio of observed data to the predicted value in each bin. The hashed band in the upper panel shows the total uncertainty in the background prediction, including statistical and systematic components. The $ {{p_{\mathrm {T}}} ^\text {miss}} $ template prediction is normalized to the first bin of the distribution, and therefore the prediction agrees with the data by construction.
png pdf	Figure 3-c: The $ {{p_{\mathrm {T}}} ^\text {miss}} $ distribution is shown for data compared to the background prediction in the on-Z strong-production SRB signal region, with no b-tagged jet. The lower panel shows the ratio of observed data to the predicted value in each bin. The hashed band in the upper panel shows the total uncertainty in the background prediction, including statistical and systematic components. The $ {{p_{\mathrm {T}}} ^\text {miss}} $ template prediction is normalized to the first bin of the distribution, and therefore the prediction agrees with the data by construction.
png pdf	Figure 3-d: The $ {{p_{\mathrm {T}}} ^\text {miss}} $ distribution is shown for data compared to the background prediction in the on-Z strong-production SRB signal region, with at least 1 b-tagged jet. The lower panel shows the ratio of observed data to the predicted value in each bin. The hashed band in the upper panel shows the total uncertainty in the background prediction, including statistical and systematic components. The $ {{p_{\mathrm {T}}} ^\text {miss}} $ template prediction is normalized to the first bin of the distribution, and therefore the prediction agrees with the data by construction.
png pdf	Figure 3-e: The $ {{p_{\mathrm {T}}} ^\text {miss}} $ distribution is shown for data compared to the background prediction in the on-Z strong-production SRC signal region, with no b-tagged jet. The lower panel shows the ratio of observed data to the predicted value in each bin. The hashed band in the upper panel shows the total uncertainty in the background prediction, including statistical and systematic components. The $ {{p_{\mathrm {T}}} ^\text {miss}} $ template prediction is normalized to the first bin of the distribution, and therefore the prediction agrees with the data by construction.
png pdf	Figure 3-f: The $ {{p_{\mathrm {T}}} ^\text {miss}} $ distribution is shown for data compared to the background prediction in the on-Z strong-production SRC signal region, with at least 1 b-tagged jet. The lower panel shows the ratio of observed data to the predicted value in each bin. The hashed band in the upper panel shows the total uncertainty in the background prediction, including statistical and systematic components. The $ {{p_{\mathrm {T}}} ^\text {miss}} $ template prediction is normalized to the first bin of the distribution, and therefore the prediction agrees with the data by construction.
png pdf	Figure 4: The $ {{p_{\mathrm {T}}} ^\text {miss}} $ distribution is shown for data compared to the background prediction in the on-Z $ {{\mathrm {V}}\mathrm{Z}} $ (left) and $\mathrm{H} \mathrm{Z} $ (right) electroweak-production SRs. The lower panel of each figure shows the ratio of observed data to the predicted value in each bin. The hashed band in the upper panels shows the total uncertainty in the background prediction, including statistical and systematic sources. The ${{p_{\mathrm {T}}} ^\text {miss}}$ template prediction for each SR is normalized to the first bin of each distribution, and therefore the prediction agrees with the data by construction.
png pdf	Figure 4-a: The $ {{p_{\mathrm {T}}} ^\text {miss}} $ distribution is shown for data compared to the background prediction in the on-Z $ {{\mathrm {V}}\mathrm{Z}} $ electroweak-production SRs. The lower panel shows the ratio of observed data to the predicted value in each bin. The hashed band in the upper panel shows the total uncertainty in the background prediction, including statistical and systematic sources. The ${{p_{\mathrm {T}}} ^\text {miss}}$ template prediction for each SR is normalized to the first bin of each distribution, and therefore the prediction agrees with the data by construction.
png pdf	Figure 4-b: The $ {{p_{\mathrm {T}}} ^\text {miss}} $ distribution is shown for data compared to the background prediction in the $\mathrm{H} \mathrm{Z} $ electroweak-production SRs. The lower panel shows the ratio of observed data to the predicted value in each bin. The hashed band in the upper panel shows the total uncertainty in the background prediction, including statistical and systematic sources. The ${{p_{\mathrm {T}}} ^\text {miss}}$ template prediction for each SR is normalized to the first bin of each distribution, and therefore the prediction agrees with the data by construction.
png pdf	Figure 5: Results of the counting experiment of the edge search. For each SR, the number of observed events, shown as black data points, is compared to the total background estimate. The hashed band shows the total uncertainty in the background prediction, including statistical and systematic sources.
png pdf	Figure 6: Fit of the dilepton mass distributions to the signal-plus-background hypothesis in the "Edge fit'' SR from Table 1, projected on the same-flavor (left) and different-flavor (right) event samples. The fit shape is shown as a solid blue line. The individual fit components are indicated by dashed and dotted lines. The FS background is shown with a black dashed line. The $ {\text {DY}{+}\text {jets}} $ background is displayed with a red dotted line. The extracted signal component is displayed with a purple dash-dotted line. The lower panel in each plot shows the difference between the observation and the fit, divided by the square root of the number of fitted events.
png pdf	Figure 6-a: Fit of the dilepton mass distribution to the signal-plus-background hypothesis in the "Edge fit'' SR from Table 1, projected on the same-flavor event sample. The fit shape is shown as a solid blue line. The individual fit components are indicated by dashed and dotted lines. The FS background is shown with a black dashed line. The $ {\text {DY}{+}\text {jets}} $ background is displayed with a red dotted line. The extracted signal component is displayed with a purple dash-dotted line. The lower panel in each plot shows the difference between the observation and the fit, divided by the square root of the number of fitted events.
png pdf	Figure 6-b: Fit of the dilepton mass distribution to the signal-plus-background hypothesis in the "Edge fit'' SR from Table 1, projected on the different-flavor event sample. The fit shape is shown as a solid blue line. The individual fit components are indicated by dashed and dotted lines. The FS background is shown with a black dashed line. The $ {\text {DY}{+}\text {jets}} $ background is displayed with a red dotted line. The extracted signal component is displayed with a purple dash-dotted line. The lower panel in each plot shows the difference between the observation and the fit, divided by the square root of the number of fitted events.
png pdf root	Figure 7: Cross section upper limit and exclusion contours at 95% CL for the gluino GMSB model as a function of the $ {\mathrm{\widetilde{g}}} $ and $ \tilde{\chi}^0_1 $ masses, obtained from the results of the strong production on-Z search. The region to the left of the thick red dotted (black solid) line is excluded by the expected (observed) limit. The thin red dotted curves indicate the regions containing 68 and 95% of the distribution of limits expected under the background-only hypothesis. The thin solid black curves show the change in the observed limit due to variation of the signal cross sections within their theoretical uncertainties.
png pdf root	Figure 8: Cross section upper limit and exclusion contours at 95% CL for the EW $\mathrm{W} \mathrm{Z} $ model as a function of the $\tilde{\chi}^{\pm}_1$ (equal to $ \tilde{\chi}^0_2 $) and $ \tilde{\chi}^0_1 $ masses, obtained using the on-Z search for EW production results. The region under the thick red dotted (black solid) line is excluded by the expected (observed) limit. The thin red dotted curves indicate the regions containing 68 and 95% of the distribution of limits expected under the background-only hypothesis. The thin solid black curves show the change in the observed limit due to variation of the signal cross sections within their theoretical uncertainties.
png pdf	Figure 9: Cross section upper limit and exclusion lines at 95% CL, as a function of the $ \tilde{\chi}^0_1 $ mass, for the search for EW production in the ZZ topology (upper) and with a 50% branching fraction to each of the Z and Higgs bosons (lower). The red band shows the theoretical cross section, with the thickness of band representing the theoretical uncertainty in the signal cross section. Regions where the black dotted line reaches below the theoretical cross section are expected to be excluded. The green (yellow) band indicates the region containing 68 (95)% of the distribution of limits expected under the background-only hypothesis. The observed upper limit on the cross section is shown with a solid black line.
png pdf root	Figure 9-a: Cross section upper limit and exclusion lines at 95% CL, as a function of the $ \tilde{\chi}^0_1 $ mass, for the search for EW production in the ZZ topology. The red band shows the theoretical cross section, with the thickness of band representing the theoretical uncertainty in the signal cross section. Regions where the black dotted line reaches below the theoretical cross section are expected to be excluded. The green (yellow) band indicates the region containing 68 (95)% of the distribution of limits expected under the background-only hypothesis. The observed upper limit on the cross section is shown with a solid black line.
png pdf root	Figure 9-b: Cross section upper limit and exclusion lines at 95% CL, as a function of the $ \tilde{\chi}^0_1 $ mass, for the search for EW production in with a 50% branching fraction to each of the Z and Higgs bosons. The red band shows the theoretical cross section, with the thickness of band representing the theoretical uncertainty in the signal cross section. Regions where the black dotted line reaches below the theoretical cross section are expected to be excluded. The green (yellow) band indicates the region containing 68 (95)% of the distribution of limits expected under the background-only hypothesis. The observed upper limit on the cross section is shown with a solid black line.
png pdf root	Figure 10: Cross section upper limit and exclusion contours at 95% CL for the slepton edge model as a function of the $\tilde{\mathrm{b}}$ and $ \tilde{\chi}^0_2 $ masses, obtained from the results of the edge search. The region to the left of the thick red dotted (black solid) line is excluded by the expected (observed) limit. The thin red dotted curves indicate the regions containing 68 and 95% of the distribution of limits expected under the background-only hypothesis. The thin solid black curves show the change in the observed limit due to variation of the signal cross sections within their theoretical uncertainties.
png pdf root	Figure 11: The covariance (upper) and correlation (lower) matrices for the background predictions in the on-Z strong-production SRs. Within each SR, the individual ${{p_{\mathrm {T}}} ^\text {miss}}$ bins are shown in increasing order starting from 100 GeV. The matrices are symmetric, but only the entries along and above the diagonal are shown for simplicity.
png pdf root	Figure 11-a: The covariance matrix for the background predictions in the on-Z strong-production SRs. Within each SR, the individual ${{p_{\mathrm {T}}} ^\text {miss}}$ bins are shown in increasing order starting from 100 GeV. The matrix is symmetric, but only the entries along and above the diagonal are shown for simplicity.
png pdf root	Figure 11-b: The correlation matrix for the background predictions in the on-Z strong-production SRs. Within each SR, the individual ${{p_{\mathrm {T}}} ^\text {miss}}$ bins are shown in increasing order starting from 100 GeV. The matrix is symmetric, but only the entries along and above the diagonal are shown for simplicity.
png pdf root	Figure 12: The covariance (upper) and correlation (lower) matrices for the background predictions in the on-Z EW-production SRs. Within each SR, the individual ${{p_{\mathrm {T}}} ^\text {miss}}$ bins are shown in increasing order starting from 100 GeV. The matrices are symmetric, but only the entries along and above the diagonal are shown for simplicity.
png pdf root	Figure 12-a: The covariance matrix for the background predictions in the on-Z EW-production SRs. Within each SR, the individual ${{p_{\mathrm {T}}} ^\text {miss}}$ bins are shown in increasing order starting from 100 GeV. The matrix is symmetric, but only the entries along and above the diagonal are shown for simplicity.
png pdf root	Figure 12-b: The correlation matrix for the background predictions in the on-Z EW-production SRs. Within each SR, the individual ${{p_{\mathrm {T}}} ^\text {miss}}$ bins are shown in increasing order starting from 100 GeV. The matrix is symmetric, but only the entries along and above the diagonal are shown for simplicity.
png pdf root	Figure 13: The covariance (upper) and correlation (lower) matrices for the background predictions in the edge strong-production SRs. The matrices are symmetric, but only the entries along and above the diagonal are shown for simplicity.
png pdf root	Figure 13-a: The covariance matrix for the background predictions in the edge strong-production SRs. The matrix is symmetric, but only the entries along and above the diagonal are shown for simplicity.
png pdf root	Figure 13-b: The correlation matrix for the background predictions in the edge strong-production SRs. The matrix is symmetric, but only the entries along and above the diagonal are shown for simplicity.

Tables
png pdf	Table 1: Summary of all SR selections.
png pdf	Table 2: Predicted and observed event yields are shown for the on-Z strong-production SRs, for each ${{p_{\mathrm {T}}} ^\text {miss}} $ bin defined in Table 1. The uncertainties shown include both statistical and systematic components.
png pdf	Table 3: Predicted and observed event yields are shown for the EW on-Z SRs, for each ${{p_{\mathrm {T}}} ^\text {miss}} $ bin defined in Table 1. The uncertainties shown include both statistical and systematic sources.
png pdf	Table 4: Predicted and observed yields in each bin of the edge search counting experiment. The uncertainties shown include both statistical and systematic sources.
png pdf	Table 5: Results of the unbinned maximum likelihood fit for event yields in the edge fit SR of Table 1, including the $ {\text {DY}{+}\text {jets}} $ and FS background components, along with the fitted signal contribution and edge position. The fitted value for $ {R_{\text {SF/DF}}} $ and the local and global signal significances in terms of standard deviations are also given. The uncertainties account for both statistical and systematic components.
png pdf	Table 6: Systematic uncertainties taken into account for the signal yields and their typical values.

Summary

A search for phenomena beyond the standard model (SM) in events with opposite-charge, same-flavor leptons, jets, and missing transverse momentum has been presented. The data used corresponds to a sample of pp collisions collected with the CMS detector in 2016 at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Searches are performed for signals with a dilepton invariant mass ($ {m_{\ell\ell}} $) compatible with the Z boson or producing a kinematic edge in the distribution of $ {m_{\ell\ell}} $. By comparing the observation to estimates for SM backgrounds obtained from data control samples, no statistically significant evidence for a signal has been observed. The search for strongly produced new physics containing an on-shell Z boson is interpreted in a model of gauge-mediated supersymmetry breaking (GMSB), where the Z bosons are produced in decay chains initiated through gluino pair production. Gluino masses below 1500-1770 GeV have been excluded, depending on the neutralino mass, extending the exclusion limits derived from the previous CMS publication by almost 500 GeV. The search for electroweak production with an on-shell Z boson has been interpreted in multiple simplified models. For chargino-neutralino production, where the neutralino decays to a Z boson and the lightest supersymmetric particle (LSP) and the chargino decays to a W boson and the LSP, we probe chargino masses in the range 160-610 GeV. In a GMSB model of neutralino-neutralino production decaying to ZZ and LSPs, we probe neutralino masses up to around 650 GeV. Assuming GMSB production where the neutralino has a branching fraction of 50% to the Z boson and 50% to the Higgs boson, we probe neutralino masses up to around 500 GeV. Compared to published CMS results using 8 TeV data, these extend the exclusion limits by around 200-300 GeV depending on the model. The search for a kinematic edge in the $ {m_{\ell\ell}} $ distribution is interpreted in a simplified model based on bottom squark pair production. Decay chains containing the two lightest neutralinos and a slepton are assumed, leading to edge-like signatures in the distribution of $ {m_{\ell\ell}} $. Bottom squark masses below 980-1200 GeV have been excluded, depending on the mass of the second neutralino. These extend the previous CMS exclusion limits in the same model by 400-600 GeV.

Additional Figures
png pdf	Additional Figure 1: PDFs for the four input variables to the likelihood discriminant: ${E_{\mathrm {T}}^{\text {miss}}}$ (a), di-lepton $ {p_{\mathrm {T}}} $ (b), $|\Delta \phi |$ between the leptons (c), and $\Sigma m_{\ell \text {b}}$ (d) for data in the OF region.
png pdf	Additional Figure 1-a: PDF for an input variable to the likelihood discriminant: ${E_{\mathrm {T}}^{\text {miss}}}$.
png pdf	Additional Figure 1-b: PDF for an input variable to the likelihood discriminant: di-lepton $ {p_{\mathrm {T}}} $.
png pdf	Additional Figure 1-c: PDF for an input variable to the likelihood discriminant: $|\Delta \phi |$ between the leptons.
png pdf	Additional Figure 1-d: PDF for an input variable to the likelihood discriminant: $\Sigma m_{\ell \text {b}}$ (d) for data in the OF region.
png pdf	Additional Figure 2: Fitted shape for backgrounds containing a Z boson for dielectron events (a) and dimuon events (b). The fitted shape consists of an exponential (green) and a Breit-wigner convolved with a double-sided Crystal-Ball (red), whose sum (blue) describes the backgrounds containing a Z boson.
png pdf	Additional Figure 2-a: Fitted shape for backgrounds containing a Z boson for dielectron events. The fitted shape consists of an exponential (green) and a Breit-wigner convolved with a double-sided Crystal-Ball (red), whose sum (blue) describes the backgrounds containing a Z boson.
png pdf	Additional Figure 2-b: Fitted shape for backgrounds containing a Z boson for dimuon events. The fitted shape consists of an exponential (green) and a Breit-wigner convolved with a double-sided Crystal-Ball (red), whose sum (blue) describes the backgrounds containing a Z boson.
png pdf	Additional Figure 3: Result of fit in signal region for same-flavor (a) and different-flavor (b) events for data evaluating the null hypothesis.
png pdf	Additional Figure 3-a: Result of fit in signal region for same-flavor events for data evaluating the null hypothesis.
png pdf	Additional Figure 3-b: Result of fit in signal region for different-flavor events for data evaluating the null hypothesis.
png pdf	Additional Figure 4: $ {m_{\ell \ell}} $ distribution in the $ {\mathrm{t} {}\mathrm{\bar{t}}} $ like (a) and non $ {\mathrm{t} {}\mathrm{\bar{t}}} $ like (b) edge signal regions.The number of observed events, shown as black data points, is compared to the total background estimate, shown as a blue line with a blue uncertainty band. The non flavor symmetric background component from instrumental $E_{\text {T}}^{\text {miss}}$ is indicated as a green area while the non flavor symmetric background with neutrinos is shown as a violet area.
png pdf	Additional Figure 4-a: $ {m_{\ell \ell}} $ distribution in the $ {\mathrm{t} {}\mathrm{\bar{t}}} $ like edge signal regions.The number of observed events, shown as black data points, is compared to the total background estimate, shown as a blue line with a blue uncertainty band. The non flavor symmetric background component from instrumental $E_{\text {T}}^{\text {miss}}$ is indicated as a green area while the non flavor symmetric background with neutrinos is shown as a violet area.
png pdf	Additional Figure 4-b: $ {m_{\ell \ell}} $ distribution in the non $ {\mathrm{t} {}\mathrm{\bar{t}}} $ like edge signal regions.The number of observed events, shown as black data points, is compared to the total background estimate, shown as a blue line with a blue uncertainty band. The non flavor symmetric background component from instrumental $E_{\text {T}}^{\text {miss}}$ is indicated as a green area while the non flavor symmetric background with neutrinos is shown as a violet area.
png pdf	Additional Figure 5: Two-dimensional distribution of the observed significances in the slepton-edge signal model.
png pdf	Additional Figure 6: Summary of results in all the on-Z signal regions. The three blocks on the left correspond to the on-Z signal regions targeting the gluino GMSB signal model, while the two blocks on the right correspond to the on-Z signal regions looking for electroweakly produced new physics.
png pdf	Additional Figure 7: Summary of results in the on-Z signal regions targeting the gluino GMSB model.

Additional Tables
png pdf	Additional Table 1: Cut flow table for the edge signal model for a mass point at $m_{\tilde{b}}=$ 900 GeV and $m_{\tilde{\chi}_{2}^{0}}=$ 150 GeV. Expected dilepton events refers to luminosity$\times $cross section$\times $branching ratio.
png pdf	Additional Table 2: Cut flow table for the edge signal model for a mass point at $m_{\tilde{b}}=$ 900 GeV and $m_{\tilde{\chi}_{2}^{0}}=$ 500 GeV. Expected dilepton events refers to luminosity$\times $cross section$\times $branching ratio.
png pdf	Additional Table 3: Cut flow table for the edge signal model for a mass point at $m_{\tilde{b}}=$ 1000 GeV and $m_{\tilde{\chi}_{2}^{0}}=$ 300 GeV. Expected dilepton events refers to luminosity$\times $cross section$\times $branching ratio.
png pdf	Additional Table 4: Cut flow table for the edge signal model for a mass point at $m_{\tilde{b}}=$ 1200 GeV and $m_{\tilde{\chi}_{2}^{0}}=$ 200 GeV. Expected dilepton events refers to luminosity$\times $cross section$\times $branching ratio.
png pdf	Additional Table 5: Cut flow table for the edge signal model for a mass point at $m_{\tilde{b}}=$ 1200 GeV and $m_{\tilde{\chi}_{2}^{0}}=$ 1000 GeV. Expected dilepton events refers to luminosity$\times $cross section$\times $branching ratio.
png pdf	Additional Table 6: Cut flow table for the strong on-Z signal region selections for the gluino GMSB signal model with the mass of the gluino and the $\tilde{\chi}_{1}^{0}$ equal to 1400 and 700 GeV, respectively. The theoretical cross section for this signal is 25.3 fb and at least one Z boson was required to decay leptonically, for a branching fraction of 0.192.
png pdf	Additional Table 7: Cut flow table for the electroweak on-Z signal region selections for the WZ signal model with the mass of the chargino and the LSP equal to 550 and 200 GeV, respectively. The theoretical cross section for this signal is 30.2 fb and the Z boson was required to decay leptonically, for a branching fraction of 0.10.
png pdf	Additional Table 8: Cut flow table for the electroweak on-Z signal region selections for the ZZ signal model with the mass of the higginos equal to 350 GeV. The theoretical cross section for this signal is 154 fb (assuming scenario 1 from the text) and at least one Z boson was required to decay leptonically, for a branching fraction of 0.192.
png pdf	Additional Table 9: Cut flow table for the electroweak on-Z signal region selections for the HZ signal model with the mass of the higginos equal to 350 GeV. Only HZ events are considered here and a 100% branching fraction of the sparticles to the HZ final state is assumed in these numbers. The theoretical cross section for this signal is 154 fb (assuming scenario 1 from the text). The Z boson was required to decay leptonically and the Higgs boson to decay to ${\mathrm{b} \mathrm{\bar{b}}}$, for a branching fraction of 0.059.

Code for calculating the $ M_{\mathrm{T2}} $ variable can be found here. A macro for calculating the nll variable and the RooWorkSpace with the fitted pdfs used for the calculation is available here.

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