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| CMS-PAS-HIN-19-001 | ||
| Evidence for top quark production in nucleus-nucleus collisions | ||
| CMS Collaboration | ||
| November 2019 | ||
| Abstract: Evidence for the production of top quarks in heavy ion collisions is reported in a data sample of lead-lead collisions recorded in 2018 by the CMS experiment at a nucleon-nucleon center-of-mass energy of $\sqrt{\smash[b]{s_{_{\mathrm{NN}}}}} = $ 5.02 TeV, corresponding to an integrated luminosity of 1.7 $\pm$ 0.1 nb$^{-1}$. Top quark pair ($\mathrm{t\bar{t}}$) production is measured in events with two opposite-sign high-$p_{\mathrm{T}}$ isolated leptons ($\ell^\pm\ell^\mp =\,\mathrm{e}^{+} \mathrm{e}^{-},\,\mu^{+} \mu^{-}$ , and $\mathrm{e}^{\pm} \mu^{\mp}$). We test the sensitivity to the $\mathrm{t\bar{t}}$ signal process by requiring or not the additional presence of b-tagged jets, and hence the feasilibility to identify top quark decay products irrespective of interacting with the medium (bottom quarks) or not (leptonically decaying W bosons). To that end, the inclusive cross section ($\sigma_{\mathrm{t\bar{t}}}$) is derived from likelihood fits to a multivariate discriminator, which includes different leptonic kinematic variables, with and without the b-tagged jet multiplicity information. The observed (expected) significance of the $\mathrm{t\bar{t}}$ signal against the background-only hypothesis is 4.0 (6.0) and 3.8 (4.8) standard deviations, respectively, for the fits with and without the b-jet multiplicity input. After event reconstruction and background subtraction, the extracted cross sections are $\sigma_{\mathrm{t\bar{t}}} = $ 2.02 $\pm$ 0.69 and 2.56 $\pm$ 0.82 $\mu$b, respectively, which are consistent with each other and lower than, but still compatible with, the expectations from scaled proton-proton data as well as from perturbative quantum chromodynamics predictions. This measurement constitutes the first step towards using the top quark as a novel tool for probing strongly interacting matter. | ||
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Links:
CDS record (PDF) ;
CADI line (restricted) ;
These preliminary results are superseded in this paper, PRL 125 (2020) 222001. The superseded preliminary plots can be found here.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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| Figures | |
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Figure 1:
Observed (markers) and prefit expected (filled histograms) BDT discriminator distributions in the ${\mathrm{e} ^+ \mathrm{e} ^-}$ (left), ${\mu ^+ \mu ^-}$ (middle), and ${\mathrm{e} ^\pm \mu ^\mp}$ (right) channels. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the prefit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the prefit uncertainties in the predictions. |
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Figure 1-a:
Observed (markers) and prefit expected (filled histograms) BDT discriminator distributions in the ${\mathrm{e} ^+ \mathrm{e} ^-}$ channel. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the prefit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panel displays the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the prefit uncertainties in the predictions. |
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Figure 1-b:
Observed (markers) and prefit expected (filled histograms) BDT discriminator distributions in the ${\mu ^+ \mu ^-}$ channel. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the prefit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panel displays the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the prefit uncertainties in the predictions. |
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Figure 1-c:
Observed (markers) and prefit expected (filled histograms) BDT discriminator distributions in the ${\mathrm{e} ^\pm \mu ^\mp}$ channel. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the prefit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panel displays the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the prefit uncertainties in the predictions. |
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Figure 2:
Observed (markers) and prefit expected (filled histograms) BDT discriminator distributions in the ${\mathrm{e} ^+ \mathrm{e} ^-}$ (left), ${\mu ^+ \mu ^-}$ (middle), and ${\mathrm{e} ^\pm \mu ^\mp}$ (right) channels separately for the 0b-, 1b-, and 2b-jet multiplicity categories. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the prefit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the prefit uncertainties in the predictions. |
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Figure 2-a:
Observed (markers) and prefit expected (filled histograms) BDT discriminator distributions in the ${\mathrm{e} ^+ \mathrm{e} ^-}$ channel separately for the 0b-, 1b-, and 2b-jet multiplicity categories. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the prefit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panel displays the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the prefit uncertainties in the predictions. |
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Figure 2-b:
Observed (markers) and prefit expected (filled histograms) BDT discriminator distributions in the ${\mu ^+ \mu ^-}$ channel separately for the 0b-, 1b-, and 2b-jet multiplicity categories. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the prefit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panel displays the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the prefit uncertainties in the predictions. |
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Figure 2-c:
Observed (markers) and prefit expected (filled histograms) BDT discriminator distributions in the ${\mathrm{e} ^\pm \mu ^\mp}$ channel separately for the 0b-, 1b-, and 2b-jet multiplicity categories. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the prefit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panel displays the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the prefit uncertainties in the predictions. |
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Figure 3:
Observed (markers) and postfit predicted (filled histograms) BDT discriminator distributions in the ${\mathrm{e} ^+ \mathrm{e} ^-}$ (left), ${\mu ^+ \mu ^-}$ (middle), and ${\mathrm{e} ^\pm \mu ^\mp}$ (right) channels. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Figure 3-a:
Observed (markers) and postfit predicted (filled histograms) BDT discriminator distributions in the ${\mathrm{e} ^+ \mathrm{e} ^-}$ channel. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panel displays the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Figure 3-b:
Observed (markers) and postfit predicted (filled histograms) BDT discriminator distributions in the ${\mu ^+ \mu ^-}$ channel. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panel displays the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Figure 3-c:
Observed (markers) and postfit predicted (filled histograms) BDT discriminator distributions in the ${\mathrm{e} ^\pm \mu ^\mp}$ channel. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panel displays the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Figure 4:
Observed (markers) and postfit predicted (filled histograms) BDT discriminator distributions in the ${\mathrm{e} ^+ \mathrm{e} ^-}$ (left), ${\mu ^+ \mu ^-}$ (middle), and ${\mathrm{e} ^\pm \mu ^\mp}$ (right) channels separately for the 0b-, 1b-, and 2b-jet multiplicity categories. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Figure 4-a:
Observed (markers) and postfit predicted (filled histograms) BDT discriminator distributions in the ${\mathrm{e} ^+ \mathrm{e} ^-}$ channel separately for the 0b-, 1b-, and 2b-jet multiplicity categories. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panel displays the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Figure 4-b:
Observed (markers) and postfit predicted (filled histograms) BDT discriminator distributions in the ${\mu ^+ \mu ^-}$ channel separately for the 0b-, 1b-, and 2b-jet multiplicity categories. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panel displays the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Figure 4-c:
Observed (markers) and postfit predicted (filled histograms) BDT discriminator distributions in the ${\mathrm{e} ^\pm \mu ^\mp}$ channel separately for the 0b-, 1b-, and 2b-jet multiplicity categories. The data are shown with markers, and the signal and background processes with filled histograms. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of $ {\mathrm{t} \mathrm{\bar{t}}} $ signal and backgrounds. The lower panel displays the ratio of the data to the predictions, including the $ {\mathrm{t} \mathrm{\bar{t}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Figure 5:
Inclusive $ {\mathrm{t} \mathrm{\bar{t}}} $ cross sections measured in the combined ${\mathrm{e} ^+ \mathrm{e} ^-}$, ${\mu ^+ \mu ^-}$, and ${\mathrm{e} ^\pm \mu ^\mp}$ final states in PbPb collisions (divided by the mass number squared, $A^2$), compared to theoretical NNLO+NNLL predictions [32], and pp results at $ {\sqrt {\smash [b]{s_{_{\mathrm {NN}}}}}} =$ 5.02 TeV [17]. The total experimental error bars (theoretical error bands) include statistical and systematic (PDF and scale) uncertainties added in quadrature. |
| Tables | |
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Table 1:
Number of expected background and signal events, and observed event yields in the $\mathrm{e} ^+\mathrm{e} ^-$, $\mu ^+\mu ^-$, and $\mathrm{e} ^\pm \mu ^\mp $ event categories for the three b jet multiplicities (0-b, 1-b, 2-b) after all selection criteria and the signal extraction fit. |
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Table 2:
Observed impact of each source of uncertainty in the signal strength $\mu $, for the leptonic-only and leptonic+b-tagged analyses. The total uncertainty is obtained from the covariance matrix of the fits. The values quoted are symmetrized. |
| Summary |
| In summary, evidence for top quark pair production in nucleus-nucleus collisions has been presented for the first time, using lead-lead data at ${\sqrt {\smash [b]{s_{_{\mathrm {NN}}}}}} = $ 5.02 TeV with a total integrated luminosity of 1.7 $\pm$ 0.1 nb$^{-1}$. The measurement is performed analyzing events with at least one pair of isolated and oppositely charged leptons ($\ell^\pm\ell^\mp =\,\mathrm{e}^{+} \mathrm{e}^{-},\,\mu^{+} \mu^{-}$ , and $\mathrm{e}^{\pm} \mu^{\mp}$) with large transverse momenta, as well as adding the information on the number of jets tagged as originating from the hadronization of bottom quarks. The inclusive cross section (${\sigma_{\mathrm{t\bar{t}}}} $) is derived from likelihood fits to a multivariate discriminator, which includes different leptonic kinematic variables. Using the dilepton categories with and without the b-tagged jet multiplicity information, we demonstrate that top quark decay products are identified, irrespective of whether interacting with the medium or not. The measured cross sections are ${\sigma_{\mathrm{t\bar{t}}}} = $ 2.02 $\pm$ 0.69 (tot) and 2.56 $\pm$ 0.82 (tot) $\mu$b, respectively. These values are consistent with each other and lower, but still compatible, with respect to the expectations from scaled pp data as well as from perturbative quantum chromodynamics calculations. The observed (expected) significance of the $ \mathrm{t\bar{t}}$ signal against the background-only hypothesis are 4.0 (6.0) and 3.8 (4.8) standard deviations in the two cases, respectively. This first measurement paves the way for further detailed investigations of top quark production in nuclear interactions, providing, in particular, a new tool for studies of the strongly interacting matter created in nucleus-nucleus collisions. |
| Additional Figures | |
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Additional Figure 1:
Invariant mass distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ (left), ${{{\mu}}^+ {{\mu}}^-}$ (middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the prefit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the prefit uncertainties in the predictions. |
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Additional Figure 1-a:
Invariant mass distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ (left), ${{{\mu}}^+ {{\mu}}^-}$ (middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the prefit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the prefit uncertainties in the predictions. |
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Additional Figure 1-b:
Invariant mass distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ (left), ${{{\mu}}^+ {{\mu}}^-}$ (middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the prefit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the prefit uncertainties in the predictions. |
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Additional Figure 1-c:
Invariant mass distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ (left), ${{{\mu}}^+ {{\mu}}^-}$ (middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the prefit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the prefit uncertainties in the predictions. |
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Additional Figure 2:
Postfit predicted multiplicity distributions of the b-tagged jets ($N_{\mathrm {b-tag}}$) in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ (left), ${{{\mu}}^+ {{\mu}}^-}$ (middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. The distribution of the Z/$\gamma ^{*}$ background is taken from the data. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Additional Figure 2-a:
Postfit predicted multiplicity distributions of the b-tagged jets ($N_{\mathrm {b-tag}}$) in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ (left), ${{{\mu}}^+ {{\mu}}^-}$ (middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. The distribution of the Z/$\gamma ^{*}$ background is taken from the data. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Additional Figure 2-b:
Postfit predicted multiplicity distributions of the b-tagged jets ($N_{\mathrm {b-tag}}$) in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ (left), ${{{\mu}}^+ {{\mu}}^-}$ (middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. The distribution of the Z/$\gamma ^{*}$ background is taken from the data. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Additional Figure 2-c:
Postfit predicted multiplicity distributions of the b-tagged jets ($N_{\mathrm {b-tag}}$) in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ (left), ${{{\mu}}^+ {{\mu}}^-}$ (middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. The distribution of the Z/$\gamma ^{*}$ background is taken from the data. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Additional Figure 3:
Transverse momentum distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Additional Figure 3-a:
Transverse momentum distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Additional Figure 3-b:
Transverse momentum distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Additional Figure 3-c:
Transverse momentum distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Additional Figure 3-d:
Transverse momentum distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Additional Figure 3-e:
Transverse momentum distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Additional Figure 3-f:
Transverse momentum distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Additional Figure 4:
Acoplanarity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
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Additional Figure 4-a:
Acoplanarity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 4-b:
Acoplanarity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 4-c:
Acoplanarity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 4-d:
Acoplanarity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 4-e:
Acoplanarity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 4-f:
Acoplanarity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 5:
Sphericity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 5-a:
Sphericity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 5-b:
Sphericity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 5-c:
Sphericity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 5-d:
Sphericity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 5-e:
Sphericity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 5-f:
Sphericity distributions of the lepton pairs in the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ ($\text {BDT} > 0.5$, left), ${{\mathrm {e}}^+ {\mathrm {e}}^-}$ and ${{{\mu}}^+ {{\mu}}^-}$(middle), and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ (right) channels. In the top (bottom) row the prefit (postfit) expectations (predictions) are compared to data. The comparison between the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and the background-subtracted data is shown for the postfit distributions as inset panels. Backgrounds and signal are shown with the filled histograms and data are shown with the markers. The vertical bars on the markers represent the statistical uncertainties in data. The hatched regions show the postfit uncertainties in the sum of ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal and backgrounds. The lower panels display the ratio of the data to the predictions, including the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal, with bands representing the postfit uncertainties in the predictions. |
png pdf |
Additional Figure 6:
Distributions for the two reconstructed jets with the highest b tagging discriminator value in the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal (red) and Z/$\gamma ^{*}$ (cyan) background MC simulation. The generator level transverse momentum is shown on the top, while the b tagging discriminator output on the bottom. The left (right) distributions correspond to the leading (subleading) in b tagging discriminator jet. |
png pdf |
Additional Figure 6-a:
Distributions for the two reconstructed jets with the highest b tagging discriminator value in the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal (red) and Z/$\gamma ^{*}$ (cyan) background MC simulation. The generator level transverse momentum is shown on the top, while the b tagging discriminator output on the bottom. The left (right) distributions correspond to the leading (subleading) in b tagging discriminator jet. |
png pdf |
Additional Figure 6-b:
Distributions for the two reconstructed jets with the highest b tagging discriminator value in the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal (red) and Z/$\gamma ^{*}$ (cyan) background MC simulation. The generator level transverse momentum is shown on the top, while the b tagging discriminator output on the bottom. The left (right) distributions correspond to the leading (subleading) in b tagging discriminator jet. |
png pdf |
Additional Figure 6-c:
Distributions for the two reconstructed jets with the highest b tagging discriminator value in the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal (red) and Z/$\gamma ^{*}$ (cyan) background MC simulation. The generator level transverse momentum is shown on the top, while the b tagging discriminator output on the bottom. The left (right) distributions correspond to the leading (subleading) in b tagging discriminator jet. |
png pdf |
Additional Figure 6-d:
Distributions for the two reconstructed jets with the highest b tagging discriminator value in the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal (red) and Z/$\gamma ^{*}$ (cyan) background MC simulation. The generator level transverse momentum is shown on the top, while the b tagging discriminator output on the bottom. The left (right) distributions correspond to the leading (subleading) in b tagging discriminator jet. |
png pdf |
Additional Figure 7:
Scan of the profile likelihood (left), distribution of signal strength $\mu $ (middle), distribution of significances (right) expected in pseudo-experiments (blue curves and histograms) and observed in data (green curves and lines) for the signal extraction fit in the leptonic-only measurement. |
png pdf |
Additional Figure 7-a:
Scan of the profile likelihood (left), distribution of signal strength $\mu $ (middle), distribution of significances (right) expected in pseudo-experiments (blue curves and histograms) and observed in data (green curves and lines) for the signal extraction fit in the leptonic-only measurement. |
png pdf |
Additional Figure 7-b:
Scan of the profile likelihood (left), distribution of signal strength $\mu $ (middle), distribution of significances (right) expected in pseudo-experiments (blue curves and histograms) and observed in data (green curves and lines) for the signal extraction fit in the leptonic-only measurement. |
png pdf |
Additional Figure 7-c:
Scan of the profile likelihood (left), distribution of signal strength $\mu $ (middle), distribution of significances (right) expected in pseudo-experiments (blue curves and histograms) and observed in data (green curves and lines) for the signal extraction fit in the leptonic-only measurement. |
png pdf |
Additional Figure 8:
Scan of the profile likelihood (left), distribution of signal strength $\mu $ (middle), distribution of significances (right) expected in pseudo-experiments (blue curves and histograms) and observed in data (green curves and lines) for the signal extraction fit in the leptonic+b-tagged measurement. |
png pdf |
Additional Figure 8-a:
Scan of the profile likelihood (left), distribution of signal strength $\mu $ (middle), distribution of significances (right) expected in pseudo-experiments (blue curves and histograms) and observed in data (green curves and lines) for the signal extraction fit in the leptonic+b-tagged measurement. |
png pdf |
Additional Figure 8-b:
Scan of the profile likelihood (left), distribution of signal strength $\mu $ (middle), distribution of significances (right) expected in pseudo-experiments (blue curves and histograms) and observed in data (green curves and lines) for the signal extraction fit in the leptonic+b-tagged measurement. |
png pdf |
Additional Figure 8-c:
Scan of the profile likelihood (left), distribution of signal strength $\mu $ (middle), distribution of significances (right) expected in pseudo-experiments (blue curves and histograms) and observed in data (green curves and lines) for the signal extraction fit in the leptonic+b-tagged measurement. |
png pdf |
Additional Figure 9:
Impacts $\mu $ estimated after performing the fit to the data for the leptonic-only (left) and the leptonic+b-tagged (right) measurements. Only the 15 leading nuisance parameters are shown. |
png pdf |
Additional Figure 9-a:
Impacts $\mu $ estimated after performing the fit to the data for the leptonic-only (left) and the leptonic+b-tagged (right) measurements. Only the 15 leading nuisance parameters are shown. |
png pdf |
Additional Figure 9-b:
Impacts $\mu $ estimated after performing the fit to the data for the leptonic-only (left) and the leptonic+b-tagged (right) measurements. Only the 15 leading nuisance parameters are shown. |
png pdf |
Additional Figure 10:
Distribution of events as a function of the decimal logarithm of $S/B$, where $S$ and $B$ are the prefit expected ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal (with $\mu =1$) and background yields, respectively, in BDT bins of similar prefit expected signal-to-background ratio. The shaded histogram shows the prefit expected background distribution. The red histogram, stacked on top of the background histogram, show the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal prefit expectation. The lower panel shows the ratios of the observed results and prefit expected $ {{\mathrm {t}\overline {\mathrm {t}}}}$ signal relative to the prefit expected background. The leptonic-only (leptonic+ b-tagged) measurement is shown on the left (right). |
png pdf |
Additional Figure 10-a:
Distribution of events as a function of the decimal logarithm of $S/B$, where $S$ and $B$ are the prefit expected ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal (with $\mu =1$) and background yields, respectively, in BDT bins of similar prefit expected signal-to-background ratio. The shaded histogram shows the prefit expected background distribution. The red histogram, stacked on top of the background histogram, show the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal prefit expectation. The lower panel shows the ratios of the observed results and prefit expected $ {{\mathrm {t}\overline {\mathrm {t}}}}$ signal relative to the prefit expected background. The leptonic-only (leptonic+ b-tagged) measurement is shown on the left (right). |
png pdf |
Additional Figure 10-b:
Distribution of events as a function of the decimal logarithm of $S/B$, where $S$ and $B$ are the prefit expected ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal (with $\mu =1$) and background yields, respectively, in BDT bins of similar prefit expected signal-to-background ratio. The shaded histogram shows the prefit expected background distribution. The red histogram, stacked on top of the background histogram, show the ${{\mathrm {t}\overline {\mathrm {t}}}} $ signal prefit expectation. The lower panel shows the ratios of the observed results and prefit expected $ {{\mathrm {t}\overline {\mathrm {t}}}}$ signal relative to the prefit expected background. The leptonic-only (leptonic+ b-tagged) measurement is shown on the left (right). |
| Additional Tables | |
png pdf |
Additional Table 1:
Signal strength $\mu $ and significance in standard deviations including only the ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ channel in the fit and compared to the ${{\mathrm {e}}^+ {\mathrm {e}}^-}$, ${{{\mu}}^+ {{\mu}}^-}$, and ${{\mathrm {e}}^\pm {{\mu}}^\mp}$ measurements. The observed (expected) results of the fits are reported. |
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