Measurement of the polarisation of single top quarks and antiquarks produced in the $t$-channel at $\sqrt{s}=13$ TeV and bounds on the $\textit{tWb}$ dipole operator from the ATLAS experiment
A simultaneous measurement of the three components of the top-quark and top-antiquark polarisation vectors in $t$-channel single-top-quark production is presented. This analysis is based on data from proton-proton collisions at a centre-of-mass energy of 13 TeV corresponding to an integrated luminosity of 139 fb$^{-1}$, collected with the ATLAS detector at the LHC. Selected events contain exactly one isolated electron or muon, large missing transverse momentum and exactly two jets, one being $b$-tagged. Stringent selection requirements are applied to discriminate $t$-channel single-top-quark events from the background contributions. The top-quark and top-antiquark polarisation vectors are measured from the distributions of the direction cosines of the charged-lepton momentum in the top-quark rest frame. The three components of the polarisation vector for the selected top-quark event sample are $P_{x'} =0.01\pm0.18$, $P_{y'} = -0.029\pm0.027$, $P_{z'} =0.91\pm0.10$ and for the top-antiquark event sample they are $P_{x'} = -0.02\pm0.20$, $P_{y'} = -0.007\pm0.051$, $P_{z'} = -0.79\pm 0.16$. Normalised differential cross-sections corrected to a fiducial region at the stable-particle level are presented as a function of the charged-lepton angles for top-quark and top-antiquark events inclusively and separately. These measurements are in agreement with Standard Model predictions. The angular differential cross-sections are used to derive bounds on the complex Wilson coefficient of the dimension-six $\mathcal{O}_{tW}$ operator in the framework of an effective field theory. The obtained bounds are $C_{tW} \in\ [-0.9,1.4]$ and $C_{itW} \in [-0.8,0.2]$, both at 95% confidence level.
23 February 2022
Contact: Top conveners
internal
e-print arXiv:2202.11382 - pdf from arXiv
Figures
Figure 01a
Feynman diagrams for the processes contributing to t-channel single-top-quark production at LO, in the five-flavour scheme. In the dominant subprocess, an up- or down-type quark from one of the colliding protons interacts with a bottom quark or antiquark from the other proton by exchanging a virtual W boson to produce a (a) top quark or (d) top antiquark. In the subdominant subprocess, a down- or up-type antiquark from one of the colliding protons interacts with a bottom quark or antiquark from another proton by exchanging a virtual W boson to produce a (b) top quark or (c) top antiquark.
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Figure 01b
Feynman diagrams for the processes contributing to t-channel single-top-quark production at LO, in the five-flavour scheme. In the dominant subprocess, an up- or down-type quark from one of the colliding protons interacts with a bottom quark or antiquark from the other proton by exchanging a virtual W boson to produce a (a) top quark or (d) top antiquark. In the subdominant subprocess, a down- or up-type antiquark from one of the colliding protons interacts with a bottom quark or antiquark from another proton by exchanging a virtual W boson to produce a (b) top quark or (c) top antiquark.
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Figure 01c
Feynman diagrams for the processes contributing to t-channel single-top-quark production at LO, in the five-flavour scheme. In the dominant subprocess, an up- or down-type quark from one of the colliding protons interacts with a bottom quark or antiquark from the other proton by exchanging a virtual W boson to produce a (a) top quark or (d) top antiquark. In the subdominant subprocess, a down- or up-type antiquark from one of the colliding protons interacts with a bottom quark or antiquark from another proton by exchanging a virtual W boson to produce a (b) top quark or (c) top antiquark.
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Figure 01d
Feynman diagrams for the processes contributing to t-channel single-top-quark production at LO, in the five-flavour scheme. In the dominant subprocess, an up- or down-type quark from one of the colliding protons interacts with a bottom quark or antiquark from the other proton by exchanging a virtual W boson to produce a (a) top quark or (d) top antiquark. In the subdominant subprocess, a down- or up-type antiquark from one of the colliding protons interacts with a bottom quark or antiquark from another proton by exchanging a virtual W boson to produce a (b) top quark or (c) top antiquark.
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Figure 02
Diagram illustrating the three orthogonal directions x̂', ŷ' and ẑ' used in this analysis, as seen in the zero-momentum frame of the initial-state quarks. The ẑ' direction is that of the spectator quark in the top-quark rest frame. The x̂' direction lies in the production plane, while the ŷ' direction is perpendicular to the production plane.
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Figure 03
Representation of the octant variable Q constructed by slicing the tridimensional phase space into eight octants, according to the signs of the three variables cosθℓ x', cosθℓ y', cosθℓ z'.
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Figure 04a
Observed data and fitted distributions of the octant variable (a) Q+ in the top-quark and (b) Q− in the top-antiquark signal regions. The Q variable is assigned an integer value zero through seven according to Q=4·Θ(cosθℓ z')+2·Θ(cosθℓ x')+Θ(cosθℓ y')where Θ(ξ) is the Heaviside step function of the variable ξ. The label "others" represents tt̄Z, tt̄W, tZq, tHq, and tWZ production. The uncertainty bands include both the statistical and systematic uncertainties. The lower panels show the ratio of data to prediction in each bin.
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Figure 04b
Observed data and fitted distributions of the octant variable (a) Q+ in the top-quark and (b) Q− in the top-antiquark signal regions. The Q variable is assigned an integer value zero through seven according to Q=4·Θ(cosθℓ z')+2·Θ(cosθℓ x')+Θ(cosθℓ y')where Θ(ξ) is the Heaviside step function of the variable ξ. The label "others" represents tt̄Z, tt̄W, tZq, tHq, and tWZ production. The uncertainty bands include both the statistical and systematic uncertainties. The lower panels show the ratio of data to prediction in each bin.
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Figure 05
Summary of the observed best-fit polarisation measurements with their statistical-only (green) and statistical+systematic (yellow) contours at 68% CL, plotted on the two-dimensional polarisation parameter space (Pz', Px'). The interior of the black circle represents the physically allowed region of the parameter space, and the red point indicates the parton-level prediction at NNLO from a calculation based on Ref. [8]. The uncertainty in the theoretical prediction includes scale, αs and PDF uncertainties. Correlations between the predictions of the polarisation parameters are not provided.
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Figure 06a
Post-fit distributions of (a) cosθℓ x', (b) cosθℓ y' and (c) cosθℓ z' in the signal region. The data, shown as the black points with statistical uncertainties, are compared with SM signal and background predictions. The multijet background is estimated using MC and data-driven techniques, while contributions from simulated W+jets and top-quark background and t-channel signal event samples are normalised to the results of a maximum-likelihood fit to event yields in the signal and control regions. The label "others" represents tt̄Z, tt̄W, tZq, tHq, and tWZ production. The uncertainty bands include both the statistical and systematic uncertainties. The lower panels show the ratio of data to prediction in each bin.
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Figure 06b
Post-fit distributions of (a) cosθℓ x', (b) cosθℓ y' and (c) cosθℓ z' in the signal region. The data, shown as the black points with statistical uncertainties, are compared with SM signal and background predictions. The multijet background is estimated using MC and data-driven techniques, while contributions from simulated W+jets and top-quark background and t-channel signal event samples are normalised to the results of a maximum-likelihood fit to event yields in the signal and control regions. The label "others" represents tt̄Z, tt̄W, tZq, tHq, and tWZ production. The uncertainty bands include both the statistical and systematic uncertainties. The lower panels show the ratio of data to prediction in each bin.
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Figure 06c
Post-fit distributions of (a) cosθℓ x', (b) cosθℓ y' and (c) cosθℓ z' in the signal region. The data, shown as the black points with statistical uncertainties, are compared with SM signal and background predictions. The multijet background is estimated using MC and data-driven techniques, while contributions from simulated W+jets and top-quark background and t-channel signal event samples are normalised to the results of a maximum-likelihood fit to event yields in the signal and control regions. The label "others" represents tt̄Z, tt̄W, tZq, tHq, and tWZ production. The uncertainty bands include both the statistical and systematic uncertainties. The lower panels show the ratio of data to prediction in each bin.
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Figure 07a
Particle-level normalised differential cross-sections as a function of (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z', along with various SM MC predictions of the t-channel signal for both top quarks and top antiquarks. The data, shown as the black points with statistical uncertainties, are compared with predictions (lines) obtained by using the Powheg-Box+Pythia8 (solid red), Protos+Pythia8 (dashed blue), MG5_aMC@NLO+Pythia8 (long-dashed green) and Powheg-Box+Herwig7 (dot-dashed violet) generators. The uncertainty bands include both the statistical and systematic uncertainties. The data statistical uncertainty is too small to be visible. The lower panels show the ratio of prediction to data in each bin.
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Figure 07b
Particle-level normalised differential cross-sections as a function of (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z', along with various SM MC predictions of the t-channel signal for both top quarks and top antiquarks. The data, shown as the black points with statistical uncertainties, are compared with predictions (lines) obtained by using the Powheg-Box+Pythia8 (solid red), Protos+Pythia8 (dashed blue), MG5_aMC@NLO+Pythia8 (long-dashed green) and Powheg-Box+Herwig7 (dot-dashed violet) generators. The uncertainty bands include both the statistical and systematic uncertainties. The data statistical uncertainty is too small to be visible. The lower panels show the ratio of prediction to data in each bin.
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Figure 07c
Particle-level normalised differential cross-sections as a function of (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z', along with various SM MC predictions of the t-channel signal for both top quarks and top antiquarks. The data, shown as the black points with statistical uncertainties, are compared with predictions (lines) obtained by using the Powheg-Box+Pythia8 (solid red), Protos+Pythia8 (dashed blue), MG5_aMC@NLO+Pythia8 (long-dashed green) and Powheg-Box+Herwig7 (dot-dashed violet) generators. The uncertainty bands include both the statistical and systematic uncertainties. The data statistical uncertainty is too small to be visible. The lower panels show the ratio of prediction to data in each bin.
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Figure 08a
Particle-level normalised differential cross-sections as a function of (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z', along with various SM MC predictions of the t-channel signal for top quarks. The data, shown as the black points with statistical uncertainties, are compared with predictions (lines) obtained by using the Powheg-Box+Pythia8 (solid red), Protos+Pythia8 (dashed blue), MG5_aMC@NLO+Pythia8 (long-dashed green) and Powheg-Box+Herwig7 (dot-dashed violet) generators. The uncertainty bands include both the statistical and systematic uncertainties. The data statistical uncertainty is too small to be visible. The lower panels show the ratio of prediction to data in each bin.
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Figure 08b
Particle-level normalised differential cross-sections as a function of (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z', along with various SM MC predictions of the t-channel signal for top quarks. The data, shown as the black points with statistical uncertainties, are compared with predictions (lines) obtained by using the Powheg-Box+Pythia8 (solid red), Protos+Pythia8 (dashed blue), MG5_aMC@NLO+Pythia8 (long-dashed green) and Powheg-Box+Herwig7 (dot-dashed violet) generators. The uncertainty bands include both the statistical and systematic uncertainties. The data statistical uncertainty is too small to be visible. The lower panels show the ratio of prediction to data in each bin.
png (134kB) pdf (45kB)
Figure 08c
Particle-level normalised differential cross-sections as a function of (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z', along with various SM MC predictions of the t-channel signal for top quarks. The data, shown as the black points with statistical uncertainties, are compared with predictions (lines) obtained by using the Powheg-Box+Pythia8 (solid red), Protos+Pythia8 (dashed blue), MG5_aMC@NLO+Pythia8 (long-dashed green) and Powheg-Box+Herwig7 (dot-dashed violet) generators. The uncertainty bands include both the statistical and systematic uncertainties. The data statistical uncertainty is too small to be visible. The lower panels show the ratio of prediction to data in each bin.
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Figure 09a
Particle-level normalised differential cross-sections as a function of (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z', along with various SM MC predictions of the t-channel signal for top antiquarks. The data, shown as the black points with statistical uncertainties, are compared with predictions (lines) obtained by using the Powheg-Box+Pythia8 (solid red), Protos+Pythia8 (dashed blue), MG5_aMC@NLO+Pythia8 (long-dashed green) and Powheg-Box+Herwig7 (dot-dashed violet) generators. The uncertainty bands include both the statistical and systematic uncertainties. The data statistical uncertainty is too small to be visible. The lower panels show the ratio of prediction to data in each bin.
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Figure 09b
Particle-level normalised differential cross-sections as a function of (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z', along with various SM MC predictions of the t-channel signal for top antiquarks. The data, shown as the black points with statistical uncertainties, are compared with predictions (lines) obtained by using the Powheg-Box+Pythia8 (solid red), Protos+Pythia8 (dashed blue), MG5_aMC@NLO+Pythia8 (long-dashed green) and Powheg-Box+Herwig7 (dot-dashed violet) generators. The uncertainty bands include both the statistical and systematic uncertainties. The data statistical uncertainty is too small to be visible. The lower panels show the ratio of prediction to data in each bin.
png (134kB) pdf (45kB)
Figure 09c
Particle-level normalised differential cross-sections as a function of (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z', along with various SM MC predictions of the t-channel signal for top antiquarks. The data, shown as the black points with statistical uncertainties, are compared with predictions (lines) obtained by using the Powheg-Box+Pythia8 (solid red), Protos+Pythia8 (dashed blue), MG5_aMC@NLO+Pythia8 (long-dashed green) and Powheg-Box+Herwig7 (dot-dashed violet) generators. The uncertainty bands include both the statistical and systematic uncertainties. The data statistical uncertainty is too small to be visible. The lower panels show the ratio of prediction to data in each bin.
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Figure 10a
Comparison of data and the result of the EFT fit for the polarisation angles (a) cosθℓ x' and (b) cosθℓ y'. The solid points show the data, unfolded to particle level. The solid red line corresponds to the EFT prediction using the best-fit values for the Wilson coefficients CtW = 0.3 and CitW = −0.3. The blue dashed line represents the SM prediction obtained with the MG5_aMC@NLO+Pythia8 generator. The brown dotted (green dash-dotted) line shows the model at its upper (lower) 95% CL bounds for (a) CtW = 1.4 (CtW =−0.9) and (b) CitW = 0.2 (CitW = −0.8) also obtained with the MG5_aMC@NLO+Pythia8 generator. The uncertainty bands include both the statistical and systematic uncertainties. The lower panel gives the ratio of the model to the data.
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Figure 10b
Comparison of data and the result of the EFT fit for the polarisation angles (a) cosθℓ x' and (b) cosθℓ y'. The solid points show the data, unfolded to particle level. The solid red line corresponds to the EFT prediction using the best-fit values for the Wilson coefficients CtW = 0.3 and CitW = −0.3. The blue dashed line represents the SM prediction obtained with the MG5_aMC@NLO+Pythia8 generator. The brown dotted (green dash-dotted) line shows the model at its upper (lower) 95% CL bounds for (a) CtW = 1.4 (CtW =−0.9) and (b) CitW = 0.2 (CitW = −0.8) also obtained with the MG5_aMC@NLO+Pythia8 generator. The uncertainty bands include both the statistical and systematic uncertainties. The lower panel gives the ratio of the model to the data.
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Figure 11
The observed best-fit value (dot) for the Wilson coefficients CtW and CitW with the uncertainty contours at 68% CL (dashed) and 95% CL (solid). The CLs are obtained in a simultaneous fit of the two parameters using the prediction obtained with the MG5_aMC@NLO+Pythia8 generator. The red star indicates the SM prediction.
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Tables
Table 01
Summary of the selection criteria defining the preselection, the signal region and the two control regions.
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Table 02
Summary of the signal selection criteria, applied to particle-level objects, for defining the fiducial region.
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Table 03
Pre-fit event yields in the preselection and signal regions and in the tt̄ and W+jets control regions for the combined electron and muon channels. The predictions are derived from simulated event samples normalised to the theoretical cross-sections. For multijet production the normalisation is estimated using a data-driven likelihood fit. The label "Others" represents tt̄Z, tt̄W, tZq, tHq, and tWZ production. The data-driven scale factors obtained for the top-quark and W+ jets background processes are not considered when computing these event yields. The uncertainties shown account for systematic effects and the uncertainty due to limited MC sample size. The expected S/B ratio and the ratio of the observed number to the expected number of events are also given.
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Table 04
Normalisation factors of the t-channel, W+jets and tt̄ processes together with the polarisation values as extracted from data, including total and statistical-only uncertainties in the fit.
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Table 05
Systematic and statistical uncertainties in the measurement of the polarisation vector P for top quarks and top antiquarks. The impact of each group of uncertainties is obtained by performing a fit where the NPs in the group are fixed to their best-fit values, subtracting the square of the resulting uncertainty in the parameter of interest (i.e. for each polarisation component) from the squared uncertainty from the nominal fit, and then taking the square root. An additional uncertainty from the JER is included, consisting of the difference between the central values of the nominal fit model and the alternative fit model in which JER variations are implemented coherently across all bins of the octant variable distribution. The total systematic uncertainty is calculated as the sum in quadrature of the individual grouped sources.
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Table 06
The χ2 and p-value of the three unfolded angular distributions for the top-quark, for the top-antiquark and for both the top-quark and top-antiquark measurements. The numbers are computed by comparing the observed data with the Powheg-Box+Pythia8 SM predictions. The NDF corresponds to the number of bins of each angular distribution minus one. A global χ2 and p-value for the three angular distributions are also included.
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Table 07
Obtained limits on the real (CtW) and imaginary (CitW) coefficient of the OtW operator. Also shown are the limits when only the terms up to a specific order in Λ are taken into account.
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Auxiliary material
Figure 01
Two-dimensional correlation among the pseudorapidities of the spectator jet (ηj) and the reconstructed top quark (ηℓνb) for the t-channel signal process (blue points) and the all backgrounds (red points). The blue dotted lines represent the trapezoidal requirement, ηj < (4 ηℓνb + a) & ηj > (4 ηℓνb - a) & (ηj > (0.44 ηℓνb + b) OR ηj < (0.44 ηℓνb - b)), with optimised intercepts: a=10 and b=2.
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Figure 02a
Relative contribution (pre-fit) of the predicted signal and background processes in the (a) preselection, (b) signal, (c) tt̄ and (d) W+jets control regions for the combined electron and muon channel. The predictions are derived from simulated event samples normalised to the theoretical cross-sections. For multijet production the normalisation is estimated using a data-driven likelihood fit. The label "Others" represents the tt̄Z, tt̄W, tZq, tHq, and tWZ productions. The data-driven scale factors obtained for the top-quark and W+jets background processes are not considered to compute these event yields.
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Figure 02b
Relative contribution (pre-fit) of the predicted signal and background processes in the (a) preselection, (b) signal, (c) tt̄ and (d) W+jets control regions for the combined electron and muon channel. The predictions are derived from simulated event samples normalised to the theoretical cross-sections. For multijet production the normalisation is estimated using a data-driven likelihood fit. The label "Others" represents the tt̄Z, tt̄W, tZq, tHq, and tWZ productions. The data-driven scale factors obtained for the top-quark and W+jets background processes are not considered to compute these event yields.
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Figure 02c
Relative contribution (pre-fit) of the predicted signal and background processes in the (a) preselection, (b) signal, (c) tt̄ and (d) W+jets control regions for the combined electron and muon channel. The predictions are derived from simulated event samples normalised to the theoretical cross-sections. For multijet production the normalisation is estimated using a data-driven likelihood fit. The label "Others" represents the tt̄Z, tt̄W, tZq, tHq, and tWZ productions. The data-driven scale factors obtained for the top-quark and W+jets background processes are not considered to compute these event yields.
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Figure 02d
Relative contribution (pre-fit) of the predicted signal and background processes in the (a) preselection, (b) signal, (c) tt̄ and (d) W+jets control regions for the combined electron and muon channel. The predictions are derived from simulated event samples normalised to the theoretical cross-sections. For multijet production the normalisation is estimated using a data-driven likelihood fit. The label "Others" represents the tt̄Z, tt̄W, tZq, tHq, and tWZ productions. The data-driven scale factors obtained for the top-quark and W+jets background processes are not considered to compute these event yields.
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Figure 03a
Separated t-channel process is shown in the octant distributions Q+ in the top-quark and Q− in the top-antiquark signal regions with Pz' = ±1 for (a) top quarks and (b) top antiquarks, for Px' = ±1 for (c) top quarks and (d) top antiquarks, and for Py' = ±1 for (e) top quarks and (f) top antiquarks. These templates are obtained with LO Protos+Pythia8 generator.
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Figure 03b
Separated t-channel process is shown in the octant distributions Q+ in the top-quark and Q− in the top-antiquark signal regions with Pz' = ±1 for (a) top quarks and (b) top antiquarks, for Px' = ±1 for (c) top quarks and (d) top antiquarks, and for Py' = ±1 for (e) top quarks and (f) top antiquarks. These templates are obtained with LO Protos+Pythia8 generator.
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Figure 03c
Separated t-channel process is shown in the octant distributions Q+ in the top-quark and Q− in the top-antiquark signal regions with Pz' = ±1 for (a) top quarks and (b) top antiquarks, for Px' = ±1 for (c) top quarks and (d) top antiquarks, and for Py' = ±1 for (e) top quarks and (f) top antiquarks. These templates are obtained with LO Protos+Pythia8 generator.
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Figure 03d
Separated t-channel process is shown in the octant distributions Q+ in the top-quark and Q− in the top-antiquark signal regions with Pz' = ±1 for (a) top quarks and (b) top antiquarks, for Px' = ±1 for (c) top quarks and (d) top antiquarks, and for Py' = ±1 for (e) top quarks and (f) top antiquarks. These templates are obtained with LO Protos+Pythia8 generator.
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Figure 03e
Separated t-channel process is shown in the octant distributions Q+ in the top-quark and Q- in the top-antiquark signal regions with Polz = pm1 for (a) top quarks and (b) top antiquarks, for Polx = pm1 for (c) top quarks and (d) top antiquarks, and for Poly = pm1 for (e) top quarks and (f) top antiquarks. These templates are obtained with LO PROTOSPYTHIA8 generator.
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Figure 03f
Separated t-channel process is shown in the octant distributions Q+ in the top-quark and Q- in the top-antiquark signal regions with Polz = pm1 for (a) top quarks and (b) top antiquarks, for Polx = pm1 for (c) top quarks and (d) top antiquarks, and for Poly = pm1 for (e) top quarks and (f) top antiquarks. These templates are obtained with LO PROTOSPYTHIA8 generator.
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Figure 04
Summary of the observed best-fit polarisation measurements with their statistical-only (green) and statistical+systematic (yellow) contours at 68% CL, plotted on the two-dimensional polarisation parameter space (Pz', Py'). The interior of the black circle represents the physically allowed region of the parameter space, and the red point indicates the parton-level prediction at NNLO from a calculation based on Ref. [8]. The uncertainty on the theoretical prediction includes scale, αs and PDF uncertainties. Correlations between the predictions of the polarisation parameters are not provided.
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Figure 05a
Summary of the observed best-fit polarisation measurements with their statistical-only (green) and statistical+systematic (yellow) contours at 68% CL, plotted on the two-dimensional polarisation parameter space (Px', Py'). The interior of the black circle represents the physically allowed region of the parameter space, and the red point indicates the parton-level prediction at NNLO from a calculation based on Ref. [8]. The uncertainty on the theoretical prediction includes scale, αs and PDF uncertainties. Correlations between the predictions of the polarisation parameters are not provided.
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Figure 05b
Summary of the observed best-fit polarisation measurements with their statistical-only (green) and statistical+systematic (yellow) contours at 68% CL, plotted on the two-dimensional polarisation parameter space (Px', Py'). The interior of the black circle represents the physically allowed region of the parameter space, and the red point indicates the parton-level prediction at NNLO from a calculation based on Ref. [8]. The uncertainty on the theoretical prediction includes scale, αs and PDF uncertainties. Correlations between the predictions of the polarisation parameters are not provided.
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Figure 06a
Migration matrices for (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z'. The angular variable at particle level is shown on the y-axis while the reconstructed angular variable is shown on the x-axis. The numbers are normalised per row and given in percentage.
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Figure 06b
Migration matrices for (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z'. The angular variable at particle level is shown on the y-axis while the reconstructed angular variable is shown on the x-axis. The numbers are normalised per row and given in percentage.
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Figure 06c
Migration matrices for (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z'. The angular variable at particle level is shown on the y-axis while the reconstructed angular variable is shown on the x-axis. The numbers are normalised per row and given in percentage.
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Figure 07a
Breakdown of the different systematic contributions for the three angular distributions including both top quarks and antiquarks: (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z'. The category "Others" includes all the uncertainties which are not included in any other group.
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Figure 07b
Breakdown of the different systematic contributions for the three angular distributions including both top quarks and antiquarks: (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z'. The category "Others" includes all the uncertainties which are not included in any other group.
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Figure 07c
Breakdown of the different systematic contributions for the three angular distributions including both top quarks and antiquarks: (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z'. The category "Others" includes all the uncertainties which are not included in any other group.
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Figure 08a
Breakdown of the different systematic contributions for the three angular distributions for top quarks: (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z'. The category "Others" includes all the uncertainties which are not included in any other group.
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Figure 08b
Breakdown of the different systematic contributions for the three angular distributions for top quarks: (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z'. The category "Others" includes all the uncertainties which are not included in any other group.
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Figure 08c
Breakdown of the different systematic contributions for the three angular distributions for top quarks: (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z'. The category "Others" includes all the uncertainties which are not included in any other group.
png (41kB) pdf (40kB)
Figure 09a
Breakdown of the different systematic contributions for the three angular distributions for top antiquarks: (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z'. The category "Others" includes all the uncertainties which are not included in any other group.
png (43kB) pdf (40kB)
Figure 09b
Breakdown of the different systematic contributions for the three angular distributions for top antiquarks: (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z'. The category "Others" includes all the uncertainties which are not included in any other group.
png (43kB) pdf (38kB)
Figure 09c
Breakdown of the different systematic contributions for the three angular distributions for top antiquarks: (a) cosθℓ x', (b) cosθℓ y', and (c) cosθℓ z'. The category "Others" includes all the uncertainties which are not included in any other group.
png (42kB) pdf (38kB)
