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arXiv · 1412.0570

Measurement of the charge asymmetry in dileptonic decays of top quark pairs in proton-proton collisions at 7 TeV using the ATLAS detector

Cécile Deterre·Liza Mijović
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Abstract

A measurement of the top--antitop ($t\bar{t}$) charge asymmetry is presented using 2011 LHC data collected by the ATLAS detector corresponding to an integrated luminosity of 4.6 fb$^{-1}$ at a centre-of-mass energy of 7 TeV. The analysis is performed in the dilepton channel, and two different observables are studied: $A^{\ell\ell}_{\mathrm{C}}$, based on the identified charged leptons, and $A^{t\bar{t}}_{\mathrm{C}}$, based on the reconstructed $t\bar{t}$ final state. The asymmetries, measured to be $A^{\ell\ell}_{\mathrm{C}} = 0.024 \pm 0.015 \mathrm{(stat.)} \pm 0.009 \mathrm{(syst.)}$ and $A^{t\bar{t}}_{\mathrm{C}} = 0.021 \pm 0.025 \mathrm{(stat.)} \pm 0.017 \mathrm{(syst.)}$, are in agreement with the Standard Model predictions.

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Cécile Deterre, Liza Mijović. 2014-12-01. Measurement of the charge asymmetry in dileptonic decays of top quark pairs in proton-proton collisions at 7 TeV using the ATLAS detector. https://arxiv.org/abs/1412.0570

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