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arXiv · 1801.03535

Measurement of the $\mathrm{Z}γ^{*} \to ττ$ cross section in pp collisions at $\sqrt{s} = $ 13 TeV and validation of $τ$ lepton analysis techniques

CMS Collaboration
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Abstract

A measurement is presented of the $\mathrm{Z}/γ^{*} \to ττ$ cross section in pp collisions at $\sqrt{s} = $ 13 TeV, using data recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 2.3 fb$^{-1}$. The product of the inclusive cross section and branching fraction is measured to be $σ(\mathrm{pp} \to \mathrm{Z}/γ^{*}\text{+X}) \, \mathcal{B}(\mathrm{Z}/γ^{*} \to ττ) = $ 1848 $\pm$ 12 (stat) $\pm$ 67 (syst+lumi) pb, in agreement with the standard model expectation, computed at next-to-next-to-leading order accuracy in perturbative quantum chromodynamics. The measurement is used to validate new analysis techniques relevant for future measurements of $τ$ lepton production. The measurement also provides the reconstruction efficiency and energy scale for $τ$ decays to hadrons+$ν_τ$ final states, determined with respective relative uncertainties of 2.2% and 0.9%.

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CMS Collaboration. 2018-09-05. Measurement of the $\mathrm{Z}γ^{*} \to ττ$ cross section in pp collisions at $\sqrt{s} = $ 13 TeV and validation of $τ$ lepton analysis techniques. https://doi.org/10.1140/epjc%2Fs10052-018-6146-9

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