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arXiv · 2003.14293

Effects of top-quark decay modeling in $t\bar{t}\gamma$ production at the LHC

Giuseppe Bevilacqua
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Abstract

We present a systematic comparison of different approaches for the modeling of $t\bar{t}\gamma$ final states with leptonic decays at the LHC. On the one hand, we consider a complete calculation at NLO QCD accuracy which includes all resonant and non-resonant diagrams. On the other hand, we consider predictions in the narrow-width approximation with top quark decays modeled at various accuracies. In this way we quantify the impact of the off-shell effects in $t\bar{t}\gamma$ production. We also discuss the relative importance of double-, single- and non-resonant contributions in the complete calculation. Finally we investigate the fraction of isolated photons from decays of top quarks, which represent a background for measurements of anomalous $t\gamma$ couplings.

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Giuseppe Bevilacqua. 2020-03-31. Effects of top-quark decay modeling in $t\bar{t}\gamma$ production at the LHC. https://doi.org/10.5506/aphyspolb.51.1267

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