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arXiv · 2212.10552

Measurement of the charge asymmetry in top-quark pair production in association with a photon with the ATLAS experiment

The ATLAS Collaboration
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Abstract

A measurement of the charge asymmetry in top-quark pair ($t\bar{t}$) production in association with a photon is presented. The measurement is performed in the single-lepton $t\bar{t}$ decay channel using proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider at CERN at a centre-of-mass-energy of 13 TeV during the years 2015-2018, corresponding to an integrated luminosity of 139 fb$^{-1}$. The charge asymmetry is obtained from the distribution of the difference of the absolute rapidities of the top quark and antiquark using a profile likelihood unfolding approach. It is measured to be $A_\text{C}=-0.003 \pm 0.029$ in agreement with the Standard Model expectation.

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The ATLAS Collaboration. 2022-12-20. Measurement of the charge asymmetry in top-quark pair production in association with a photon with the ATLAS experiment. https://doi.org/10.1016/j.physletb.2023.137848

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