CERN Accelerating science

Distribution of the number of \PQb jets in data and simulation, after the event selection, (\cmsLeft) in 2016 and (\cmsRight) in 2017 samples. The hatched band includes statistical and systematic uncertainties in the predictions. The vertical bars associated with the data points represent their statistical uncertainty. The lower panels show the ratio of the observed data event yields to those expected from simulation.

Distribution of the number of \PQb jets in data and simulation, after the event selection, (\cmsLeft) in 2016 and (\cmsRight) in 2017 samples. The hatched band includes statistical and systematic uncertainties in the predictions. The vertical bars associated with the data points represent their statistical uncertainty. The lower panels show the ratio of the observed data event yields to those expected from simulation.

Prefit (upper) and postfit (lower) distributions of the number of \PQb jets in sidereal hour bins, in 2016 and 2017 data. The gray band reflects the statistical and systematic uncertainty predicted in each bin, including correlations across bins. The vertical bars associated with the data points represent their statistical uncertainty. The lower panels show the ratio of the observed data event yields to those expected from simulation.

Prefit (upper) and postfit (lower) distributions of the number of \PQb jets in sidereal hour bins, in 2016 and 2017 data. The gray band reflects the statistical and systematic uncertainty predicted in each bin, including correlations across bins. The vertical bars associated with the data points represent their statistical uncertainty. The lower panels show the ratio of the observed data event yields to those expected from simulation.

The normalized differential cross section for \ttbar as a function of sidereal time, using combined 2016--2017 data. The error bars show statistical, as well as statistical and systematic uncertainties, including correlations across bins.

Comparison of systematic and statistical uncertainties, where the former are grouped according to the treatment of time dependence:\ uniform (flat luminosity component, background normalization, theory), correlated (trigger, luminosity stability and linearity, pileup, and MC statistical uncertainty), or uncorrelated (other experimental uncertainties) across sidereal time bins.

Number of \ttbar events reconstructed in the SME hypothesis divided by the number of events in the SM hypothesis, as a function of the number of \PQb jets and sidereal time, for the four directions of the $c_L$ coefficients. The uncertainty band represents the MC statistical uncertainty in the sample used to compute the SME hypothesis. The sinusoidal variation is arising from the $f(t)$ dependence on sidereal time, while smaller structures reflect the number of b jets in each sidereal time bin.

Fitted SME coefficients and their 68 and 95\% CL, measured in fits of single coefficients while the coefficients corresponding to the three other directions are left floating, within the $c_L$, $c_R$, $c$, and $d$ families. The error bar includes statistical and systematic uncertainties. Fitting a single coefficient, with the others fixed to the SM value, leads to negligible changes in the results.

Uncertainty breakdown for SME fits of single coefficients while the coefficients corresponding to the three other directions are left floating, by splitting according to the treatment of time dependence:\ flat across sidereal time (flat luminosity component, background normalization, theory), correlated in sidereal time bins (trigger, luminosity stability and linearity, pileup, MC statistical uncertainty, single top quark decay in the SME), systematics uncorrelated in sidereal time bins (other experimental uncertainties), and statistical uncertainty.