CERN Accelerating science

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: Comparison of observed data and predictions for (a) the \pT distribution of the leading lepton and (b) the reconstructed \ctheta distribution containing measurements from both hemispheres of the \ttbar system. All three lepton-flavour channels, \ee, \mumu and \emu, are combined. The hashed band represents the total uncertainty. The bottom panel shows the ratio of data to prediction. The rightmost bins contain the overflow events. : Caption not extracted

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: Migration matrix (Figure~\ref{fig:migration_only}) and selection efficiency per bin (Figure~\ref{fig:selEff}). The migration matrix is obtained as a result of the bin optimisation. The entries represent probabilities (expressed as percentages) for an event with $\ctheta$ in bin $i$ at parton level to have reconstructed $\ctheta$ in bin $j$ at detector level. The selection efficiency is calculated with respect to the true \ttbar dilepton events in the bin. The error bars on the selection efficiency points are too small to be seen in the distribution. : Caption not extracted

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: The unfolded \ctheta differential distribution (Figure~\ref{fig:diffXSec_single}) and the unfolded normalised \ctheta distribution (Figure~\ref{fig:fitResults}). The total statistical and systematic uncertainty per bin is shown in Figure~\ref{fig:diffXSec_single}. The parton-level distribution predicted by \POWHEGBOX interfaced with \PYTHIA is shown. An uncertainty originating from the limited number of simulated events is included in the prediction but is not visible. The unfolded normalised \ctheta distribution in data is shown with the function of Eq.~(\ref{equn:HelicityFractions}) overlaid, using the helicity fractions \fO, \fL and \fR determined from the fit. The total uncertainties are shown on data points. : Caption not extracted