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friis |
1.1 |
Tau candidates in all CMS tau identification algorithms are seeded by
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reconstructed jets. After particle-flow reconstruction, particle candidates
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friis |
1.3 |
are clustered into collections by the iterativeCone5 jet algorithm. The
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efficiencies for jet seed reconstruction are described in~\cite{PFT08001} and are near
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friis |
1.1 |
unity for both signal and background. Quality cuts (see
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~\ref{table:pftau_q_cuts} are are then applied to the constituents in the jets.
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The remaining particles are then considered a ``tau candidate.''
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\begin{table}
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\centering
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\caption{Quality cuts on tau seed jet constituents}
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\begin{tabular}{l r}
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Particle flow charged hadron candidates & \\
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\hline
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Minimum transverse momentum & 0.5 GeV/$c$ \\
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Minimum tracker hits & 3 \\
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Maximum tracker $\chi^2$ & 100 \\
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friis |
1.4 |
Maximum track transverse impact parameter & 0.03cm \\
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friis |
1.1 |
\hline \hline
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Particle flow gamma candidates & \\
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\hline
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Minimum transverse energy & 0.5 GeV \\
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\end{tabular}
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\end{table}
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The constituents of tau candidate seed jets are then divided into two
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collections, called ``signal'' and ``isolation'' collections as the method at
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this stage is identical to the process for defining the isolation annulus.
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