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arXiv · 1612.05220

Measurements of top-quark pair differential cross-sections in the $eμ$ channel in $pp$ collisions at $\sqrt{s} = 13$ TeV using the ATLAS detector

ATLAS Collaboration
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Abstract

This article presents measurements of $t\bar{t}$ differential cross-sections in a fiducial phase-space region, using an integrated luminosity of 3.2 fb$^{-1}$ of proton--proton data at a centre-of-mass energy of $\sqrt{s} = 13$ TeV recorded by the ATLAS experiment at the LHC in 2015. Differential cross-sections are measured as a function of the transverse momentum and absolute rapidity of the top quark, and of the transverse momentum, absolute rapidity and invariant mass of the $t\bar{t}$ system. The $t\bar{t}$ events are selected by requiring one electron and one muon of opposite electric charge, and at least two jets, one of which must be tagged as containing a $b$-hadron. The measured differential cross-sections are compared to predictions of next-to-leading order generators matched to parton showers and the measurements are found to be consistent with all models within the experimental uncertainties with the exception of the POWHEG-Box + HERWIG++ predictions, which differ significantly from the data in both the transverse momentum of the top quark and the mass of the $t\bar{t}$ system.

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ATLAS Collaboration. 2017-05-24. Measurements of top-quark pair differential cross-sections in the $eμ$ channel in $pp$ collisions at $\sqrt{s} = 13$ TeV using the ATLAS detector. https://doi.org/10.1140/epjc%2Fs10052-017-4821-x

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