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| CMS-PAS-SUS-16-051 | ||
| Search for top squark pair production in the single lepton final state in pp collisions at $\sqrt{s}= $ 13 TeV | ||
| CMS Collaboration | ||
| March 2017 | ||
| Abstract: A search for top squark pair production in pp collisions at $\sqrt{s}= $ 13 TeV is performed using events with a single isolated electron or muon, jets, and large transverse momentum imbalance. Results are based on a study of data from proton-proton collisions collected in 2016 with the CMS detector at the LHC corresponding to an integrated luminosity of 35.9 fb$^{-1}$. No significant excess of events is observed above the expectation from standard model processes. Exclusion limits are set in the context of supersymmetric models of pair production of top squarks that decay either to a top quark and a neutralino or to a bottom quark and a chargino. | ||
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These preliminary results are superseded in this paper, JHEP 10 (2017) 019. The superseded preliminary plots can be found here. |
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| Figures & Tables | Summary | Additional Figures & Tables | References | CMS Publications |
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| Additional information on efficiencies needed for reinterpretation of these results are available here and additional figures for speakers can be found here. |
| Figures | |
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Figure 1:
Diagrams corresponding to top squark pair production, followed by the specific decay modes targeted in this note. Top left: $pp\rightarrow \tilde{t_1}\tilde{t_1}^*\rightarrow t^{(*)}\chi ^0_1\bar{t}^{(*)}\chi ^0_1$; top right: $pp\rightarrow \tilde{t_1}\tilde{t_1}^*\rightarrow b\chi ^+_1\bar{b}\chi ^-_1$; bottom: $pp\rightarrow \tilde{t_1}\tilde{t_1}^*\rightarrow t^{(*)}\chi ^0_1b\chi ^+_1$. |
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Figure 1-a:
Diagram corresponding to top squark pair production and decay targeted in this note: $pp\rightarrow \tilde{t_1}\tilde{t_1}^*\rightarrow t^{(*)}\chi ^0_1\bar{t}^{(*)}\chi ^0_1$. |
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Figure 1-b:
Diagram corresponding to top squark pair production and decay targeted in this note: $pp\rightarrow \tilde{t_1}\tilde{t_1}^*\rightarrow b\chi ^+_1\bar{b}\chi ^-_1$. |
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Figure 1-c:
Diagram corresponding to top squark pair production and decay targeted in this note: $pp\rightarrow \tilde{t_1}\tilde{t_1}^*\rightarrow t^{(*)}\chi ^0_1b\chi ^+_1$. |
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Figure 2:
Distributions of ${E_{\mathrm {T}}^{\text {miss}}}$ for a top-enriched control region of $\mathrm{ e } \mu$ events with at least one b tagged jet. |
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Figure 3:
Comparison of the modeling of kinematic distributions in data and simulation relevant for the estimate of the single lepton backgrounds. (a) Comparison of the ${M_{\mathrm {\ell b}}}$ distribution in a control sample with 1 or 2 jets, with 60 $ < {M_{\mathrm {T}}} < $ 120 GeV. The distribution is shown separately for events with 0 and $\geq $1 jet passing the medium b-tagging working point. The lower panel shows the ratio of the the transfer factors (TF) in data and simulation from the 0 tags to the $\geq 1$ tags samples. (b) The distribution of the number of b-tagged jets in the same control sample after tightening the ${E_{\mathrm {T}}^{\text {miss}}}$ requirement to 250 GeV. The shaded band shows the uncertainty resulting from a 50% systematic uncertainty on the heavy flavor component of the W+jets sample. (c) Comparison of the ${E_{\mathrm {T}}^{\text {miss}}}$ distribution between data and simulation in the $\gamma $+jets control region. The uncertainty shown is statistical-only. |
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Figure 3-a:
Comparison of the ${M_{\mathrm {\ell b}}}$ distribution in a control sample with 1 or 2 jets, with 60 $ < {M_{\mathrm {T}}} < $ 120 GeV. The distribution is shown separately for events with 0 and $\geq $1 jet passing the medium b-tagging working point. The lower panel shows the ratio of the the transfer factors (TF) in data and simulation from the 0 tags to the $\geq 1$ tags samples. |
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Figure 3-b:
The distribution of the number of b-tagged jets in the same control sample after tightening the ${E_{\mathrm {T}}^{\text {miss}}}$ requirement to 250 GeV. The shaded band shows the uncertainty resulting from a 50% systematic uncertainty on the heavy flavor component of the W+jets sample. |
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Figure 3-c:
Comparison of the ${E_{\mathrm {T}}^{\text {miss}}}$ distribution between data and simulation in the $\gamma $+jets control region. The uncertainty shown is statistical-only. |
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Figure 4:
Observed data yields compared with SM background estimations for the 31 signal regions of Table 2 and 3. The uncertainties, which are the quadratic sums of statistical and systematic uncertainties, are shown as shaded bands. The expectations for three signal hypotheses are overlaid. The corresponding numbers in parentheses in the legend refer to the masses of the top squark and neutralino, respectively. |
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Figure 5:
The exclusion limits at 95% CL for direct top-squark production with decay $\tilde{ \mathrm{ t } }_1 \to \mathrm{ t } \tilde{\chi}^0_1 $. The interpretation is done in the two dimensional space of $m_{\tilde{ \mathrm{ t } } }$ vs. $m_{\tilde{\chi}^0_1 }$. The color indicates the 95% CL upper limit on the cross section times branching fraction at each point in the $m_{\tilde{ \mathrm{ t } }_1 }$ vs. $m_{\tilde{\chi}^0_1 }$ plane. The area to the left of and below the thick black curve represents the observed exclusion region at 95% CL, while the dashed red lines indicate the expected limit at 95% CL and their $\pm$1$ \sigma $ experiment standard deviation uncertainties. The thin black lines show the effect of the theoretical uncertainties ($\sigma _\mathrm {theory}$) on the signal cross section. The whited out region is discussed in Sec. 7. |
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Figure 6:
The exclusion limit at 95% CL for direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } }_1 \tilde{ \mathrm{ t } }_1 ^*\to \mathrm{ b \bar{b} } \tilde{\chi}^{\pm}_1 \tilde{\chi}^{\pm}_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $. The mass of the chargino is chosen to be $(m_{\tilde{ \mathrm{ t } }_1 } + m_{\tilde{\chi}^0_1 })/2$. The interpretation is done in the two dimensional space of $m_{\tilde{ \mathrm{ t } }_1 }$ vs. $m_{\tilde{\chi}^0_1 }$. The color indicates the 95% CL upper limit on the cross section times branching fraction at each point in the $m_{\tilde{ \mathrm{ t } }_1 }$ vs. $m_{\tilde{\chi}^0_1 }$ plane. The area to the left of and below the thick black curve represents the observed exclusion region at 95% CL, while the dashed red lines indicate the expected limit at 95% CL and their $\pm$1$ \sigma $ experiment standard deviation uncertainties. The thin black lines show the effect of the theoretical uncertainties ($\sigma _\mathrm {theory}$) on the signal cross section. |
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Figure 7:
The exclusion limit at 95% CL for direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } }_1 \tilde{ \mathrm{ t } }_1 ^*\to \mathrm{ t } \mathrm{ b } \tilde{\chi}^{\pm}_1 \tilde{\chi}^0_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } ^{*}\tilde{\chi}^0_1 $. The mass splitting of the chargino and neutralino is fixed to 5 GeV. The interpretation is done in the two dimensional space of $m_{\tilde{ \mathrm{ t } }_1 }$ vs. $m_{\tilde{\chi}^0_1 }$. The color indicates the 95% CL upper limit on the cross section times branching fraction at each point in the $m_{\tilde{ \mathrm{ t } }_1 }$ vs. $m_{\tilde{\chi}^0_1 }$ plane. The area to the left of and below the thick black curve represents the observed exclusion region at 95% CL, while the dashed red lines indicate the expected limit at 95% CL and their $\pm$1$ \sigma $ experiment standard deviation uncertainties. The thin black lines show the effect of the theoretical uncertainties ($\sigma _\mathrm {theory}$) on the signal cross section. |
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Figure 8:
Exclusion limits at 95% CL for direct top squark pair production for the decay mode $\tilde{ \mathrm{ t } }_1 \to \mathrm{ t } \tilde{\chi}^0_1 $. The color indicates the 95% CL upper limit on the cross section times branching fraction at each point in the $m_{\tilde{ \mathrm{ t } }_1 }-m_{\tilde{\chi}^0_1 }$ plane. The area to the left of and below the thick black curve represents the observed exclusion region at 95% CL, while the dashed red lines indicate the expected limits at 95% CL and their $\pm$1$ \sigma $ experiment standard deviation uncertainties. The thin black lines show the effect of the theoretical uncertainties $\sigma _\mathrm {theory}$ on the signal cross section. The magenta short-dashed, blue dotted, and long-short-dashed orange curves show the expected limits for the fully-hdaronic [27], single-lepton and dilepton [28] analyses, respectively. |
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Figure 9:
Exclusion limits at 95% CL for direct top squark pair production for the decay mode $\tilde{ \mathrm{ t } }_1 \to \mathrm{ b } \tilde{ \chi }^{+}_1 $, $\tilde{ \chi }^{+}_1 \to \mathrm{ W } ^{+}\tilde{\chi}^0_1 $. The mass of the chargino is chosen to be $(m_{\tilde{ \mathrm{ t } }_1 } + m_{\tilde{\chi}^0_1 })/2$. The color indicates the 95% CL upper limit on the cross section times branching fraction at each point in the $m_{\tilde{ \mathrm{ t } }_1 }-m_{\tilde{\chi}^0_1 }$ plane. The area to the left of and below the thick black curve represents the observed exclusion region at 95% CL, while the dashed red lines indicate the expected limits at 95% CL and their $\pm$1$ \sigma $ experiment standard deviation uncertainties. The thin black lines show the effect of the theoretical uncertainties $\sigma _\mathrm {theory}$ on the signal cross section. The magenta short-dashed, blue dotted, and long-short-dashed orange curves show the expected limits for the fully-hdaronic [27], single-lepton and dilepton [28] analyses, respectively. |
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Figure 10:
Correlation matrix for the background predictions for the signal regions for the standard selection (in percent). The labelling of the regions follows the convention of Fig. {fig:results}. |
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Figure 11:
Correlation matrix for the background predictions for the signal regions for the compressed selection (in percent). The labelling of the regions follows the convention of Fig. {fig:results}. |
| Tables | |
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Table 1:
Summary of the preselection. ${H_{\mathrm {T}}^{\mathrm {miss}}}$ is the magnitude of the vector sum of the transverse momenta of all jets and leptons in the event. The symbol $ {p_{\mathrm {T}}} ^{\mathrm {lep}}$ denotes the transverse momentum of the lepton, while $ {p_{\mathrm {T}}} ^{\mathrm {sum}}$ is the scalar sum of the transverse momenta of all PF candidates in a cone around the lepton but excluding the lepton. The radius of the cone is $\Delta R = $ 0.2 for $ {p_{\mathrm {T}}} ^{\mathrm {lep}} \le $ 50 GeV , and $\Delta R = $ Max(0.05, 10 GeV/$ {p_{\mathrm {T}}} ^{\mathrm {lep}}$) at higher values of lepton transverse momentum. |
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Table 2:
Definitions for the 27 signal regions of the standard selection. At least one b-tagged jet (medium WP) is required in all search regions. To suppress the W+jets background in signal regions with $ {M_{\mathrm {\ell b}}} > $ 175 GeV, a more strict requirement that at least one jet satisfies the tight b-tagging WP is made. |
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Table 3:
Summary of the compressed selection and the requirements for the four corresponding signal regions. The symbol $\Delta \phi ( {E_{\mathrm {T}}^{\text {miss}}} ,\ell ) $ denotes the angle between $ E_{\mathrm{T}}^{\text{miss}} $ and the $\vec{p}_{\mathrm{T}}$ of the lepton. |
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Table 4:
Dilepton control regions that are combined when estimating the LL background. |
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Table 5:
Result of the background estimates and signal region yields corresponding to 35.9 fb${^{-1}} $. |
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Table 6:
Summary of the systematic uncertainties for the signal efficiency with their typical values in individual signal regions. |
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Table 7:
Background predictions and data for aggregated signal regions. |
| Summary |
| We have reported on a search for top squark pair production in pp collisions at $ \sqrt{s} = $ 13 TeV in events with a single isolated electron or muon, jets, and large $E_{\mathrm{T}}^{\text{miss}}$ using 35.9 fb${^{-1}}$ of data collected with the CMS detector during the 2016 run of the LHC. The event data counts are consistent with expectations from SM processes. The results are interpreted as exclusion limits in the context of supersymmetric models with pair production of top squarks that decay either to a top quark and a neutralino or to a bottom quark and a chargino. Assuming both top squarks decay to a top quark and a neutralino, we exclude at the 95% confidence level top squark masses up to 1120 GeV for a massless neutralino and neutralino masses up to 515 GeV for a 950 GeV top squark mass. |
| Additional Figures | |
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Additional Figure 1:
Comparison between postfit and prefit background predictions and data for 35.9 fb$^{-1}$ collected during 2016 pp collisions. |
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Additional Figure 2:
Covariance matrix for the background predictions for the signal regions for the standard selection. The labelling of the regions follows the convention of correlation matrices in the appendix of the note. |
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Additional Figure 3:
Covariance matrix for the background predictions for the signal regions for the compressed selection. The labelling of the regions follows the convention of correlation matrices in the appendix of the note. |
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Additional Figure 4:
Significances for a model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ t } ^{(*)}\tilde{\chi}^0_1 $ as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. (a) Observed, (b) expected. |
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Additional Figure 4-a:
Observed significance for a model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ t } ^{(*)}\tilde{\chi}^0_1 $ as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. |
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Additional Figure 4-b:
Expected significance for a model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ t } ^{(*)}\tilde{\chi}^0_1 $ as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. |
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Additional Figure 5:
Significances for a model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} \to \mathrm{ b \bar{b} } \tilde{\chi}^{\pm}_1 \tilde{\chi}^{\pm}_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $ as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. The mass of the chargino is chosen to be $(M_{\tilde{ \mathrm{ t } } } + M_{\tilde{\chi}^0_1 })/2$. (a) Observed, (b) expected. |
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Additional Figure 5-a:
Observed significance for a model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} \to \mathrm{ b \bar{b} } \tilde{\chi}^{\pm}_1 \tilde{\chi}^{\pm}_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $ as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. The mass of the chargino is chosen to be $(M_{\tilde{ \mathrm{ t } } } + M_{\tilde{\chi}^0_1 })/2$. |
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Additional Figure 5-b:
Expected significance for a model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} \to \mathrm{ b \bar{b} } \tilde{\chi}^{\pm}_1 \tilde{\chi}^{\pm}_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $ as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. The mass of the chargino is chosen to be $(M_{\tilde{ \mathrm{ t } } } + M_{\tilde{\chi}^0_1 })/2$. |
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Additional Figure 6:
Significances for a model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 / \mathrm{ t } \tilde{\chi}^0_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $, $m_{\tilde{\chi}^{\pm}_1 } = m_{\tilde{\chi}^0_1 }+ $ 5 GeV, BR($\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 $) = BR($\tilde{ \mathrm{ t } } \to \mathrm{ t } \tilde{\chi}^0_1 $) = 0.5 as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. (a) Observed, (b) expected. |
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Additional Figure 6-a:
Observed significance for a model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 / \mathrm{ t } \tilde{\chi}^0_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $, $m_{\tilde{\chi}^{\pm}_1 } = m_{\tilde{\chi}^0_1 }+ $ 5 GeV, BR($\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 $) = BR($\tilde{ \mathrm{ t } } \to \mathrm{ t } \tilde{\chi}^0_1 $) = 0.5 as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. |
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Additional Figure 6-b:
Expected significance for a model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 / \mathrm{ t } \tilde{\chi}^0_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $, $m_{\tilde{\chi}^{\pm}_1 } = m_{\tilde{\chi}^0_1 }+ $ 5 GeV, BR($\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 $) = BR($\tilde{ \mathrm{ t } } \to \mathrm{ t } \tilde{\chi}^0_1 $) = 0.5 as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. |
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Additional Figure 7:
Exclusion limit for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 / \mathrm{ t } \tilde{\chi}^0_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $, $m_{\tilde{\chi}^{\pm}_1 } = m_{\tilde{\chi}^0_1 }+ $ 5 GeV as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$ for various choices of the branching fraction between the two decays. (a) Observed, (b) expected. |
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Additional Figure 7-a:
Observed exclusion limit for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 / \mathrm{ t } \tilde{\chi}^0_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $, $m_{\tilde{\chi}^{\pm}_1 } = m_{\tilde{\chi}^0_1 }+ $ 5 GeV as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$ for various choices of the branching fraction between the two decays. |
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Additional Figure 7-b:
Expected exclusion limit for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 / \mathrm{ t } \tilde{\chi}^0_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $, $m_{\tilde{\chi}^{\pm}_1 } = m_{\tilde{\chi}^0_1 }+ $ 5 GeV as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$ for various choices of the branching fraction between the two decays. |
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Additional Figure 8:
Exclusion limit for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ t } ^{(*)}\tilde{\chi}^0_1 $ as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$ for unpolarized top quarks (black lines), right-handed top quarks (red lines), and left-handed top quarks (blue lines). |
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Additional Figure 9:
Exclusion limits as presented in the note, with the addition of the most recent previous limits as presented during ICHEP 2016 or Moriond 2015. (a): for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ t } ^{(*)}\tilde{\chi}^0_1 $, (b): for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} \to \mathrm{ b \bar{b} } \tilde{\chi}^{\pm}_1 \tilde{\chi}^{\pm}_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $ as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. The mass of the chargino is chosen to be $(M_{\tilde{ \mathrm{ t } } } + M_{\tilde{\chi}^0_1 })/2$, (c): for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 / \mathrm{ t } \tilde{\chi}^0_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $, $m_{\tilde{\chi}^{\pm}_1 } = m_{\tilde{\chi}^0_1 }+ $ 5 GeV, BR($\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 $) = BR($\tilde{ \mathrm{ t } } \to \mathrm{ t } \tilde{\chi}^0_1 $) = 0.5. |
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Additional Figure 9-a:
Exclusion limits as presented in the note, with the addition of the most recent previous limits as presented during ICHEP 2016 or Moriond 2015, for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ t } ^{(*)}\tilde{\chi}^0_1 $. |
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Additional Figure 9-b:
Exclusion limits as presented in the note, with the addition of the most recent previous limits as presented during ICHEP 2016 or Moriond 2015, for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} \to \mathrm{ b \bar{b} } \tilde{\chi}^{\pm}_1 \tilde{\chi}^{\pm}_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $ as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. The mass of the chargino is chosen to be $(M_{\tilde{ \mathrm{ t } } } + M_{\tilde{\chi}^0_1 })/2$. |
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Additional Figure 9-c:
Exclusion limits as presented in the note, with the addition of the most recent previous limits as presented during ICHEP 2016 or Moriond 2015, for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 / \mathrm{ t } \tilde{\chi}^0_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $, $m_{\tilde{\chi}^{\pm}_1 } = m_{\tilde{\chi}^0_1 }+ $ 5 GeV, BR($\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 $) = BR($\tilde{ \mathrm{ t } } \to \mathrm{ t } \tilde{\chi}^0_1 $) = 0.5. |
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Additional Figure 10:
Exclusion limits as presented in the note, however the color map is showing the 95% confidence level on the signal strength modifier. (a): for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ t } ^{(*)}\tilde{\chi}^0_1 $, (b): for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} \to \mathrm{ b \bar{b} } \tilde{\chi}^{\pm}_1 \tilde{\chi}^{\pm}_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $ as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. The mass of the chargino is chosen to be $(M_{\tilde{ \mathrm{ t } } } + M_{\tilde{\chi}^0_1 })/2$, (c): for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 / \mathrm{ t } \tilde{\chi}^0_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $, $m_{\tilde{\chi}^{\pm}_1 } = m_{\tilde{\chi}^0_1 }+ $ 5 GeV, BR($\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 $) = BR($\tilde{ \mathrm{ t } } \to \mathrm{ t } \tilde{\chi}^0_1 $) = 0.5. |
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Additional Figure 10-a:
Exclusion limits as presented in the note, however the color map is showing the 95% confidence level on the signal strength modifier, for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ t } ^{(*)}\tilde{\chi}^0_1 $, |
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Additional Figure 10-b:
Exclusion limits as presented in the note, however the color map is showing the 95% confidence level on the signal strength modifier, for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} \to \mathrm{ b \bar{b} } \tilde{\chi}^{\pm}_1 \tilde{\chi}^{\pm}_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $ as a function of $M_{\tilde{ \mathrm{ t } } }$ and $M_{\tilde{\chi}^0_1 }$. The mass of the chargino is chosen to be $(M_{\tilde{ \mathrm{ t } } } + M_{\tilde{\chi}^0_1 })/2$, |
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Additional Figure 10-c:
Exclusion limits as presented in the note, however the color map is showing the 95% confidence level on the signal strength modifier, for the model of direct top-squark production with decay $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \overline{\tilde{\mathrm{t}}} $, $\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 / \mathrm{ t } \tilde{\chi}^0_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $, $m_{\tilde{\chi}^{\pm}_1 } = m_{\tilde{\chi}^0_1 }+ $ 5 GeV, BR($\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 $) = BR($\tilde{ \mathrm{ t } } \to \mathrm{ t } \tilde{\chi}^0_1 $) = 0.5. |
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Additional Figure 11:
Background predictions and data for the aggregated signal regions using 35.9 fb$^{-1}$collected during 2016 pp collisions. |
| Additional Tables | |
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Additional Table 1:
Cutflow table for $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \tilde{ \mathrm{ t } } ^{*}\to \mathrm{ t \bar{t} } \tilde{\chi}^0_1 \tilde{\chi}^0_1 $ signals for an integrated luminosity of 35.9 fb$^{-1}$. The uncertainties are purely statistical. No correction for signal contamination in data control regions are applied. |
png pdf |
Additional Table 2:
Cutflow table for $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \tilde{ \mathrm{ t } } ^{*}, \tilde{ \mathrm{ t } } \to \mathrm{ t } \tilde{\chi}^0_1 / \mathrm{ b } \tilde{\chi}^{\pm}_1 $ signals for an integrated luminosity of 35.9 fb$^{-1}$. The branching fraction for this model is BR($\tilde{ \mathrm{ t } } \to \mathrm{ t } \tilde{\chi}^0_1 $) = BR($\tilde{ \mathrm{ t } } \to \mathrm{ b } \tilde{\chi}^{\pm}_1 $) = 0.5, and $M_{\tilde{\chi}^{\pm}_1 } = M_{\tilde{\chi}^0_1 } + 5 GeV $. The uncertainties are purely statistical. No correction for signal contamination in data control regions are applied. |
png pdf |
Additional Table 3:
Cutflow table for $\mathrm{ p } \mathrm{ p } \to \tilde{ \mathrm{ t } } \tilde{ \mathrm{ t } } ^{*}\to \mathrm{ b \bar{b} } \tilde{\chi}^{\pm}_1 \tilde{\chi}^{\pm}_1 $, $\tilde{\chi}^{\pm}_1 \to \mathrm{ W } \tilde{\chi}^0_1 $ signals with $M_{\tilde{\chi}^{\pm}_1 } = (M_{\tilde{ \mathrm{ t } } }+M_{\tilde{\chi}^0_1 })/2$ for an integrated luminosity of 35.9 fb$^{-1}$. The uncertainties are purely statistical. No correction for signal contamination in data control regions are applied. |
|
Electronic version of the limit curves can be found as three rootfiles
here,
here, and
here.
The correlation and covariance matrices can be found as two rootfiles here, and here. A code snippet to calculate the tmod variables together with an example how to use it is provided here. |
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