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| CMS-PAS-SUS-16-013 | ||
| Search for $R$-parity-violating SUSY in final states with zero or one lepton and large multiplicity of jets and b-tagged jets | ||
| CMS Collaboration | ||
| August 2016 | ||
| Abstract: Preliminary results are reported from a search for physics beyond the standard model in proton-proton collisions at $\sqrt{s}=$ 13 TeV, focusing on the signature of large multiplicity of jets and b-tagged jets, in a final state with zero or one reconstructed lepton. The data sample corresponds to an integrated luminosity of 2.7 fb$^{-1},$ recorded by the CMS experiment at the Large Hadron Collider. The results are interpreted in terms of limits on the parameter space for the $R$-parity-violating supersymmetric extension of the standard model in a benchmark model of gluino pair production where each gluino decays via $\tilde{\rm g} \rightarrow {\rm tbs}$. Assuming the gluino decays solely to tbs, gluino masses smaller than 1360 GeV are excluded at a 95% confidence level. | ||
| Links: CDS record (PDF) ; inSPIRE record ; CADI line (restricted) ; | ||
| Figures | |
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Figure 1:
Fit to the CSV distribution in data in the CSV $> $ 0.89 region for $ {H_{\mathrm {T}}} >$ 1.5 TeV , $N_\text {b}\geq$ 2, and 6 $ \leq N_{\textrm {jet}} \leq $ 7. Error bars indicate the statistical uncertainties in the simulated samples (most of which are smaller than the line width) and the data. |
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Figure 2-a:
Distributions of $\Delta R_{ { {\mathrm {b}} {\overline {\mathrm {b}}} } }$ after normalization in the $\Delta R_{ { {\mathrm {b}} {\overline {\mathrm {b}}} } } \geq$ 2.4 region for selections of $N_{\textrm {jet}} =$ 4-5 (a) and $N_{\textrm {jet}} =$ 6-7 (b). Events are required to have zero leptons, with $M_\text {J}> $ 500 GeV and $ {N_{\textrm {b}}}=$ 2. As shown by the red lines, the contribution from signal events is negligible for the gluino masses considered here. |
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Figure 2-b:
Distributions of $\Delta R_{ { {\mathrm {b}} {\overline {\mathrm {b}}} } }$ after normalization in the $\Delta R_{ { {\mathrm {b}} {\overline {\mathrm {b}}} } } \geq$ 2.4 region for selections of $N_{\textrm {jet}} =$ 4-5 (a) and $N_{\textrm {jet}} =$ 6-7 (b). Events are required to have zero leptons, with $M_\text {J}> $ 500 GeV and $ {N_{\textrm {b}}}=$ 2. As shown by the red lines, the contribution from signal events is negligible for the gluino masses considered here. |
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Figure 3-a:
Background systematic uncertainties in the fit regions with the best signal sensitivity. The selection used in the top plot is $N_\text {lep} =$ 0, $N_\text {jet} \geq $ 10, $ {H_{\mathrm {T}}} > $ 1.5 TeV , and $M_\text {J} > $ 800 GeV and the selection used in the bottom plot is $N_\text {lep} = $ 1, $N_\text {jet} \geq $ 8, $ {H_{\mathrm {T}}} > $ 1.2 TeV, and $M_\text {J} > $ 800 GeV. |
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Figure 3-b:
Background systematic uncertainties in the fit regions with the best signal sensitivity. The selection used in the top plot is $N_\text {lep} =$ 0, $N_\text {jet} \geq $ 10, $ {H_{\mathrm {T}}} > $ 1.5 TeV , and $M_\text {J} > $ 800 GeV and the selection used in the bottom plot is $N_\text {lep} = $ 1, $N_\text {jet} \geq $ 8, $ {H_{\mathrm {T}}} > $ 1.2 TeV, and $M_\text {J} > $ 800 GeV. |
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Figure 4-a:
Signal systematic uncertainties for $m_{ \tilde{\mathrm{g}} } = $ 1200 GeV in the signal regions with the best signal sensitivity. The selection used in the top plot is $N_\text {lep} = $ 0, $N_\text {jet} \geq $ 10, $ {H_{\mathrm {T}}} > $ 1500 GeV , and $M_\text {J} > $ 800 GeV and the selection used in the bottom plot is $N_\text {lep} = $ 1, $N_\text {jet} \geq $ 8, $ {H_{\mathrm {T}}} > $ 1200 GeV , and $M_\text {J} > $ 800 GeV. |
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Figure 4-b:
Signal systematic uncertainties for $m_{ \tilde{\mathrm{g}} } = $ 1200 GeV in the signal regions with the best signal sensitivity. The selection used in the top plot is $N_\text {lep} = $ 0, $N_\text {jet} \geq $ 10, $ {H_{\mathrm {T}}} > $ 1500 GeV , and $M_\text {J} > $ 800 GeV and the selection used in the bottom plot is $N_\text {lep} = $ 1, $N_\text {jet} \geq $ 8, $ {H_{\mathrm {T}}} > $ 1200 GeV , and $M_\text {J} > $ 800 GeV. |
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Figure 5-a:
Fit to data in the validation regions with $N_\text {lep}= $ 0. Plots in the left column require 500 $ < M_\text {J} < $ 800 GeV, while $ M_\text {J} > $ 800 GeV is required in the right column. The top row shows the 4 $ \leq N_\text {jet} \leq $ 5 region, and the bottom row shows the 6 $ \leq N_\text {jet} \leq $ 7 region. The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
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Figure 5-b:
Fit to data in the validation regions with $N_\text {lep}= $ 0. Plots in the left column require 500 $ < M_\text {J} < $ 800 GeV, while $ M_\text {J} > $ 800 GeV is required in the right column. The top row shows the 4 $ \leq N_\text {jet} \leq $ 5 region, and the bottom row shows the 6 $ \leq N_\text {jet} \leq $ 7 region. The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
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Figure 5-c:
Fit to data in the validation regions with $N_\text {lep}= $ 0. Plots in the left column require 500 $ < M_\text {J} < $ 800 GeV, while $ M_\text {J} > $ 800 GeV is required in the right column. The top row shows the 4 $ \leq N_\text {jet} \leq $ 5 region, and the bottom row shows the 6 $ \leq N_\text {jet} \leq $ 7 region. The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
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Figure 5-d:
Fit to data in the validation regions with $N_\text {lep}= $ 0. Plots in the left column require 500 $ < M_\text {J} < $ 800 GeV, while $ M_\text {J} > $ 800 GeV is required in the right column. The top row shows the 4 $ \leq N_\text {jet} \leq $ 5 region, and the bottom row shows the 6 $ \leq N_\text {jet} \leq $ 7 region. The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
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Figure 6-a:
Fit to data in the validation regions with $N_\text {lep}=$ 1. Plot (a) requires 500 $ < M_\text {J} < $ 800 GeV , while $M_\text {J}> $ 800 GeV is required on plot (b). The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
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Figure 6-b:
Fit to data in the validation regions with $N_\text {lep}=$ 1. Plot (a) requires 500 $ < M_\text {J} < $ 800 GeV , while $M_\text {J}> $ 800 GeV is required on plot (b). The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
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Figure 7-a:
The post-fit $N_\text {b}$ distributions in the 0-lepton signal region. Plots in the left column require 500 $ < M_\text {J} < $ 800 GeV, while $M_\text {J}> $ 800 GeV is required in the right column. The top row shows the 8 $ \leq N_\text {jet} \leq $ 9 signal region, and the bottom row shows the $N_\text {jet} \geq $ 10 signal region. The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
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Figure 7-b:
The post-fit $N_\text {b}$ distributions in the 0-lepton signal region. Plots in the left column require 500 $ < M_\text {J} < $ 800 GeV, while $M_\text {J}> $ 800 GeV is required in the right column. The top row shows the 8 $ \leq N_\text {jet} \leq $ 9 signal region, and the bottom row shows the $N_\text {jet} \geq $ 10 signal region. The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
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Figure 7-c:
The post-fit $N_\text {b}$ distributions in the 0-lepton signal region. Plots in the left column require 500 $ < M_\text {J} < $ 800 GeV, while $M_\text {J}> $ 800 GeV is required in the right column. The top row shows the 8 $ \leq N_\text {jet} \leq $ 9 signal region, and the bottom row shows the $N_\text {jet} \geq $ 10 signal region. The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
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Figure 7-d:
The post-fit $N_\text {b}$ distributions in the 0-lepton signal region. Plots in the left column require 500 $ < M_\text {J} < $ 800 GeV, while $M_\text {J}> $ 800 GeV is required in the right column. The top row shows the 8 $ \leq N_\text {jet} \leq $ 9 signal region, and the bottom row shows the $N_\text {jet} \geq $ 10 signal region. The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
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Figure 8-a:
The post-fit $N_\text {b}$ distributions in the 1-lepton signal region. Plots in the left column require 500 $ < M_\text {J} < $ 80 GeV , while $M_\text {J} > $ 800 GeV is required in the right column. The top row shows the 6 $ \leq N_\text {jet} \leq $ 7 signal region, and the bottom row shows the $N_\text {jet} \geq $ 8 signal region. The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
png pdf |
Figure 8-b:
The post-fit $N_\text {b}$ distributions in the 1-lepton signal region. Plots in the left column require 500 $ < M_\text {J} < $ 80 GeV , while $M_\text {J} > $ 800 GeV is required in the right column. The top row shows the 6 $ \leq N_\text {jet} \leq $ 7 signal region, and the bottom row shows the $N_\text {jet} \geq $ 8 signal region. The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
png pdf |
Figure 8-c:
The post-fit $N_\text {b}$ distributions in the 1-lepton signal region. Plots in the left column require 500 $ < M_\text {J} < $ 80 GeV , while $M_\text {J} > $ 800 GeV is required in the right column. The top row shows the 6 $ \leq N_\text {jet} \leq $ 7 signal region, and the bottom row shows the $N_\text {jet} \geq $ 8 signal region. The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
png pdf |
Figure 8-d:
The post-fit $N_\text {b}$ distributions in the 1-lepton signal region. Plots in the left column require 500 $ < M_\text {J} < $ 80 GeV , while $M_\text {J} > $ 800 GeV is required in the right column. The top row shows the 6 $ \leq N_\text {jet} \leq $ 7 signal region, and the bottom row shows the $N_\text {jet} \geq $ 8 signal region. The uncertainty displayed in the ratio plot as error bars reflects data statistics only. |
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Figure 9:
Cross section upper limits at 95% CL compared to the gluino pair production cross section (magenta). The expected limits (black solid line) and their $\pm$ 1 standard deviation (green) and $\pm$ 2 standard deviation (yellow) limits are shown. The observed limit is displayed as a black solid line with dots. |
| Tables | |
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Table 1:
A representation of the bins of the analysis after the baseline selection. The bins labeled ``CR'' are background dominated and serve as a control region for the fit, while the bins labeled ``SR'' correspond to signal regions. Even within the high $N_\text {jet}$ and $M_\text {J}$ bins, events with $ {N_{\textrm {b}}} \le $ 2 are background dominated and act as control regions for the fit. |
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Table 2:
Post-fit normalization of backgrounds, data, and expected yields for a gluino with $m_{ \tilde{\mathrm{g}}}=$ 1200 GeV in events with $N_\text {lep}=$ 0 and $ {H_{\mathrm {T}}} > $ 1500 GeV. Systematic uncertainties are included. |
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Table 3:
Post-fit normalization of backgrounds, data, and expected yields for a gluino with $m_{ \tilde{\mathrm{g}}}= $ 1200 GeV in events with $N_\text {lep}= $ 1 and $ {H_{\mathrm {T}}} > $ 1200 GeV. Systematic uncertainties are included. |
| Summary |
| A search has been performed for new physics in high multiplicity final states with zero or one reconstructed lepton. The data used in this analysis were collected by the CMS experiment at $ \sqrt{s} = $ 13 TeV and correspond to an integrated luminosity of 2.7 fb$^{-1}$. The results of the search are interpreted in the context of $R$-parity-violating supersymmetry with a model in which the gluino decays exclusively to $\mathrm{t }\mathrm{b }\mathrm{s}$. No significant excesses are observed, and cross section limits have been set at 95% confidence level. These limits correspond to the exclusion of gluino masses of $m_{\tilde{\mathrm{g}}} < $ 1360 GeV within this scenario. |
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