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arXiv · 2411.18209

Measurements of $t\bar{t}$ in association with charm quarks at 13 TeV with the ATLAS experiment

Knut Zoch
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Abstract

This talk presents the ATLAS Collaboration's first measurement of the inclusive cross-section for top-quark pair production in association with charm quarks. Using the full Run 2 proton-proton collision data sample at $\sqrt{s}$ = 13 TeV, collected with the ATLAS experiment at the LHC between 2015 and 2018, the measurement selects $t\bar{t}$ events with one or two charged leptons and at least one additional jet in the final state. A custom flavour-tagging algorithm is employed to simultaneously identify $b$-jets and $c$-jets. The fiducial cross-sections for $t\bar{t}+{\geq}2c$ and $t\bar{t}+1c$ production are found to largely agree with predictions from various $t\bar{t}$ simulations, though all underpredict the observed values.

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Knut Zoch. 2024-11-27. Measurements of $t\bar{t}$ in association with charm quarks at 13 TeV with the ATLAS experiment. https://doi.org/10.21468/scipostphysproc.18.004

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