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Feynman diagrams for the production of $\cPq^*\to \cPq\Z,\:\Z \to \Pgmp \Pgmm$ via (\cmsLeft) a gauge interaction and (\cmsRight) a contact interaction. Charge conjugation of an initial state quark is implied in both diagrams. Permutation of the quark isospin is implied for the contact interaction diagram.

Feynman diagrams for the production of $\cPq^*\to \cPq\Z,\:\Z \to \Pgmp \Pgmm$ via (\cmsLeft) a gauge interaction and (\cmsRight) a contact interaction. Charge conjugation of an initial state quark is implied in both diagrams. Permutation of the quark isospin is implied for the contact interaction diagram.

Distributions of \invPtMuMu~for data (points with error bars), simulated SM backgrounds (stacked histograms), and simulated signal models (overlaid histograms). Top: linear scale. Bottom: logarithmic scale. The signal models use either gauge interaction (GI) or contact interaction (CI) simulated with the assumptions of $f=\fp=\fs=1$ and $\Mqst=\Lambda$. The blue solid line corresponds to the analytical template fit in the region defined as \invPtMuMu~$\in$~[0.0028,~0.008]\invGeV. The contribution labeled ``Non--DY Background'' represents the sum over all the other sources of prompt backgrounds, \ttbar, $\Z \to \Pgt^+\Pgt^-$, diboson, and non--prompt backgrounds, jets misidentified as muons through multijet and W plus jets final states. The total number of SM background events is rescaled to the number of events observed in data, using the relative background contributions as obtained from simulation. The normalization of the signal distributions is increased by a factor ten.

Distributions of \invPtMuMu~for data (points with error bars), simulated SM backgrounds (stacked histograms), and simulated signal models (overlaid histograms). Top: linear scale. Bottom: logarithmic scale. The signal models use either gauge interaction (GI) or contact interaction (CI) simulated with the assumptions of $f=\fp=\fs=1$ and $\Mqst=\Lambda$. The blue solid line corresponds to the analytical template fit in the region defined as \invPtMuMu~$\in$~[0.0028,~0.008]\invGeV. The contribution labeled ``Non--DY Background'' represents the sum over all the other sources of prompt backgrounds, \ttbar, $\Z \to \Pgt^+\Pgt^-$, diboson, and non--prompt backgrounds, jets misidentified as muons through multijet and W plus jets final states. The total number of SM background events is rescaled to the number of events observed in data, using the relative background contributions as obtained from simulation. The normalization of the signal distributions is increased by a factor ten.

Observed and expected 95\% CL upper limits on the cross section of $\qStar \to \cPq\Z$ for the benchmark models derived with the CL$_{\mathrm{s}}$ limit setting criterion: (top) gauge interaction production, (bottom) contact interaction production. The results shown are obtained assuming all new couplings equal to the SM couplings between ordinary fermions ($f=\fp=\fs=1$) and $\Lambda=\Mqst$.

Observed and expected 95\% CL upper limits on the cross section of $\qStar \to \cPq\Z$ for the benchmark models derived with the CL$_{\mathrm{s}}$ limit setting criterion: (top) gauge interaction production, (bottom) contact interaction production. The results shown are obtained assuming all new couplings equal to the SM couplings between ordinary fermions ($f=\fp=\fs=1$) and $\Lambda=\Mqst$.

Contours of excluded parameters for the gauge and contact interaction \qStar~production mechanisms. For a given $\fs$~assumption, each (\Mqst, $\Lambda$) below the limit curve is excluded. The bump in the $\Lambda$ contour at $\Mqst=700\GeV$ for the gauge interaction production models is a direct consequence of the downward fluctuation on the upper limit on the cross section observed at $\Mqst=700\GeV$ (Figure~\ref{fig:limits}).