CERN Accelerating science

Pair production of a leptoquark (LQ) and its subsequent decay into a $b$-quark and a $\tau$-lepton.

Pair production of a leptoquark (LQ) and its subsequent decay into a $b$-quark and a $\tau$-lepton.

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: : The expected acceptance times efficiency for the scalar and vector LQs, with both the minimal-coupling and the Yang--Mills scenarios, at $\beta = 0.5$ as a function of \mlq\ in the (a) \lephad\ and (b) \hadhad\ channels. The values include the leptonic and hadronic branching ratios of the tau lepton.

: : The expected acceptance times efficiency (including object identification and reconstruction, triggering, and event selection) for the scalar and vector LQs, with both the minimal-coupling and the Yang--Mills scenarios, at $\beta = 0.5$ as a function of \mlq\ in the (a) \lephad\ and (b) \hadhad\ channels. The values include the leptonic and hadronic branching ratios of the tau lepton. The error bars, which are in general smaller than the markers, indicate the statistical uncertainty.

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: Signal (solid lines), post-fit background (filled histograms) and data (dots with error bars) distributions of representative PNN input variables in the \lephad\ SR: (a) $\Delta R(\ell, \text{jet})$, (b), $m(\tauhad, \text{jet})$ and (c) $\st$. The normalisation and shape of the backgrounds are determined from the background-only likelihood fit to data and the ratios of the data to the sum of the predicted backgrounds are shown in the lower panels. `Other' refers to the sum of minor backgrounds (vector boson + jets, diboson and Higgs boson). The hatched band indicates the combined statistical and systematic uncertainty in the total background prediction. The expected signal for a 1.4\,\TeV\ scalar LQ, scaled by the indicated factor for visibility, is overlaid. The last bin includes the overflow. : Caption not extracted

: Signal (solid lines), post-fit background (filled histograms) and data (dots with statistical error bars) distributions of representative PNN input variables in the \lephad\ SR: (a) $\Delta R(\ell, \text{jet})$, (b), $m(\tauhad, \text{jet})$ and (c) $\st$. The normalisation and shape of the backgrounds are determined from the background-only likelihood fit to data and the ratios of the data to the sum of the predicted backgrounds are shown in the lower panels. `Other' refers to the sum of minor backgrounds (vector boson + jets, diboson and Higgs boson). The hatched band indicates the combined statistical and systematic uncertainty in the total background prediction. The expected signal for a 1.4\,\TeV\ scalar LQ, scaled by the indicated factor for visibility, is overlaid. The last bin includes the overflow. : Caption not extracted

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: Signal (solid lines), post-fit background (filled histograms) and data (dots with error bars) distributions of representative PNN input variables in the \hadhad\ SR: (a) $\Delta R(\tauhad^0, \text{jet})$ where $\tauhad^0$ is the leading $\tau$-lepton, (b) the larger of the two $\tau$-jet mass combinations $m(\tauhad, \text{jet})_0$ and (c) $\st$. The normalisation and shape of the backgrounds are determined from the background-only likelihood fit to data and the ratios of the data to the sum of the predicted backgrounds are shown in the lower panels. `Other' refers to the sum of minor backgrounds (vector boson + jets, diboson and Higgs boson). The hatched band indicates the combined statistical and systematic uncertainty in the total background prediction. The expected signal for a 1.4\,\TeV\ scalar LQ, scaled by the indicated factor for visibility, is overlaid. The last bin includes the overflow. : Caption not extracted

: Signal (solid lines), post-fit background (filled histograms) and data (dots with statistical error bars) distributions of representative PNN input variables in the \hadhad\ SR: (a) $\Delta R(\tauhad^0, \text{jet})$ where $\tauhad^0$ is the leading $\tau$-lepton, (b) the larger of the two $\tau$-jet mass combinations $m(\tauhad, \text{jet})_0$ and (c) $\st$. The normalisation and shape of the backgrounds are determined from the background-only likelihood fit to data and the ratios of the data to the sum of the predicted backgrounds are shown in the lower panels. `Other' refers to the sum of minor backgrounds (vector boson + jets, diboson and Higgs boson). The hatched band indicates the combined statistical and systematic uncertainty in the total background prediction. The expected signal for a 1.4\,\TeV\ scalar LQ, scaled by the indicated factor for visibility, is overlaid. The last bin includes the overflow. : Caption not extracted

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Post-fit plots for true and misidentified $\tauhadvis$ in the $\tauhadvis$ CR, in an example $\pt$ bin ($\tauhadvis$ $\pt$ $>$100~\GeV). `Other' refers to the sum of minor backgrounds (vector boson + jets, diboson and Higgs boson). The lower panels show the ratios of the data to the sum of the predicted backgrounds. The hatched bands indicate the combined statistical and systematic uncertainty in the total background predictions. The dashed lines denote the total pre-fit backgrounds for comparison, while the last bins include the overflow.

: : Post-fit plots for true and misidentified $\tauhadvis$ in (a) the $\tauhadvis$ and (b) the anti-$\tauhadvis$ CRs, in a single $\pt$ bin ($\tauhadvis$ $\pt$ $>$100~\GeV). `Other' refers to the sum of minor backgrounds (vector boson + jets, diboson and Higgs boson). The lower panels show the ratios of the data to the sum of the predicted backgrounds. The hatched bands indicate the combined statistical and systematic uncertainty in the total background predictions. The dashed lines denote the total pre-fit backgrounds for comparison, while the last bins include the overflow.

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: The PNN score distributions in the \lephad\ SR for (a) $\mlq = 500$\,\GeV, (b) $\mlq = 1.1$\,\TeV, (c) $\mlq = 1.4$\,\TeV. The normalisation and shape of the backgrounds are determined from the background-only likelihood fit to data and the ratios of the data to the sum of the backgrounds are shown in the lower panels. `Other' refers to the sum of minor backgrounds (vector boson + jets, diboson and Higgs boson). The hatched bands indicate the combined statistical and systematic uncertainty in the total background predictions. The expected signals for scalar LQs with the corresponding masses, scaled by the indicated factors for visibility, are overlaid. Since the PNN score itself is not a physical quantity, it is represented solely by the bin number. : Caption not extracted

: The PNN score distributions in the \lephad\ SR for (a) $\mlq = 500$\,\GeV, (b) $\mlq = 1.1$\,\TeV, (c) $\mlq = 1.4$\,\TeV. The normalisation and shape of the backgrounds are determined from the background-only likelihood fit to data and the ratios of the data to the sum of the backgrounds are shown in the lower panels. `Other' refers to the sum of minor backgrounds (vector boson + jets, diboson and Higgs boson). The hatched bands indicate the combined statistical and systematic uncertainty in the total background predictions. The expected signals for scalar LQs with the corresponding masses, scaled by the indicated factors for visibility, are overlaid. Since the PNN score itself is not a physical quantity, it is represented solely by the bin number. : Caption not extracted

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: The PNN score distributions in the \hadhad\ SR for (a) $\mlq = 500$\,\GeV, (b) $\mlq = 1.1$\,\TeV, (c) $\mlq = 1.4$\,\TeV. The normalisation and shape of the backgrounds are determined from the background-only likelihood fit to data and the ratios of the data to the sum of the backgrounds are shown in the lower panels. `Other' refers to the sum of minor backgrounds (vector boson + jets, diboson and Higgs boson). The hatched bands indicate the combined statistical and systematic uncertainty in the total background predictions. The expected signals for scalar LQs with the corresponding masses, scaled by the indicated factors for visibility, are overlaid. Since the PNN score itself is not a physical quantity, it is represented solely by the bin number. : Caption not extracted

: The PNN score distributions in the \hadhad\ SR for (a) $\mlq = 500$\,\GeV, (b) $\mlq = 1.1$\,\TeV, (c) $\mlq = 1.4$\,\TeV. The normalisation and shape of the backgrounds are determined from the background-only likelihood fit to data and the ratios of the data to the sum of the backgrounds are shown in the lower panels. `Other' refers to the sum of minor backgrounds (vector boson + jets, diboson and Higgs boson). The hatched bands indicate the combined statistical and systematic uncertainty in the total background predictions. The expected signals for scalar LQs with the corresponding masses, scaled by the indicated factors for visibility, are overlaid. Since the PNN score itself is not a physical quantity, it is represented solely by the bin number. : Caption not extracted

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: The observed (solid line) and expected (dashed line) 95\% CL upper limits on the LQ pair production cross-sections assuming $\BR = 1$ as a function of \mlq\ for (a) the scalar LQ case, (b) the vector LQ case in the minimal-coupling scenario, (c) vector LQs in the Yang--Mills scenario. The surrounding shaded bands correspond to the $\pm 1$ and $\pm 2 $ standard deviation ($\pm 1 \sigma, \pm 2 \sigma$) uncertainty in the expected limit. The theoretical prediction in each model, along with its uncertainty, is shown by the lines with the hatched bands. : Caption not extracted

: The observed (solid line) and expected (dashed line) 95\% CL upper limits on the LQ pair production cross-sections assuming $\BR = 1$ as a function of \mlq\ for (a) the scalar LQ case, (b) the vector LQ case in the minimal-coupling scenario, (c) vector LQs in the Yang--Mills scenario. The surrounding shaded bands correspond to the $\pm 1$ and $\pm 2 $ standard deviation ($\pm 1 \sigma, \pm 2 \sigma$) uncertainty in the expected limit. The theoretical prediction in each model, along with its uncertainty, is shown by the lines with the hatched bands. : Caption not extracted

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: The observed (solid line) and expected (dashed line) 95\% CL upper limits on the branching ratio into charged leptons as a function of \mlq\ for (a) the scalar LQ case, (b) the vector LQ case in the minimal-coupling scenario, (c) vector LQs in the Yang--Mills scenario. The observed exclusion region is above the solid line, with the theoretical uncertainty in the model indicated by the dotted lines around this. The expected limit is indicated by the dashed line and the surrounding shaded bands correspond to the $\pm 1$ and $\pm 2 $ standard deviation ($\pm 1 \sigma, \pm 2 \sigma$) uncertainty in the expected limit. No limits are presented for $\BR < 0.1$ due to the lack of expected signal events in this final state. : Caption not extracted

: The observed (solid line) and expected (dashed line) 95\% CL upper limits on the branching ratio into charged leptons as a function of \mlq\ for (a) the scalar LQ case, (b) the vector LQ case in the minimal-coupling scenario, (c) vector LQs in the Yang--Mills scenario. The observed exclusion region is above the solid line, with the theoretical uncertainty in the model indicated by the dotted lines around this. The expected limit is indicated by the dashed line and the surrounding shaded bands correspond to the $\pm 1$ and $\pm 2 $ standard deviation ($\pm 1 \sigma, \pm 2 \sigma$) uncertainty in the expected limit. No limits are presented for $\BR < 0.1$ due to the lack of expected signal events in this final state. : Caption not extracted