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arXiv · 1901.04408

Top-quark pair production in association with a $Z$ boson in the 4$\ell$ channel with the ATLAS experiment

Sebastian Heer
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Abstract

The cross section of the $t\bar{t}Z$~and $t\bar{t}W$~processes are measured in a simultaneous fit using 36.1 $\text{fb}^{-1}$ of of proton--proton collisions at a centre-of-mass energy of $\sqrt{s}=13$ TeV recorded by the ATLAS experiment at the LHC. In addition, a fit is performed in the 4$\ell$ channel only, resulting in a cross section of $\sigma_{t\bar{t}Z} = 1.07 \pm 0.26 \,\text{pb}$. This result is consistent with the combined fit and agrees with the prediction by the Standard Model.

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Sebastian Heer. 2019-01-14. Top-quark pair production in association with a $Z$ boson in the 4$\ell$ channel with the ATLAS experiment. https://arxiv.org/abs/1901.04408

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