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arXiv · 2106.02059

Automated EW corrections with isolated photons: $t \bar t \gamma$, $t \bar t \gamma\gamma$ and $t \gamma j$ as case studies

Davide Pagani·Hua-Sheng Shao·Ioannis Tsinikos·Marco Zaro
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Abstract

In this work we compute for the first time the so-called Complete-NLO predictions for top-quark pair hadroproduction in association with at least one isolated photon ($ t \bar t \gamma$). We also compute NLO QCD+EW predictions for the similar case with at least two isolated photons ($ t \bar t \gamma\gamma$) and for single-top hadroproduction in association with at least one isolated photon. In addition, we complement our results with NLO QCD+EW predictions of the hadronic and leptonic decays of top-quark including an isolated photon. All these results have been obtained in a completely automated approach, by extending the capabilities of the MadGraph5_aMC@NLO framework and enabling the Complete-NLO predictions for processes with isolated photons in the final state. We discuss the technical details of the implementation, which involves a mixed EW renormalisation scheme for such processes.

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Davide Pagani, Hua-Sheng Shao, Ioannis Tsinikos, Marco Zaro. 2021-06-03. Automated EW corrections with isolated photons: $t \bar t \gamma$, $t \bar t \gamma\gamma$ and $t \gamma j$ as case studies. https://doi.org/10.1007/jhep09(2021)155

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