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arXiv · 2008.00918

Full NLO QCD corrections to off-shell ttbb production

Ansgar Denner·Jean-Nicolas Lang·Mathieu Pellen
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Abstract

In this article, we report on the computation of the NLO QCD corrections to ${\rm p}{\rm p} \to \mu^-\bar\nu_{\mu}{\rm e}^+\nu_{\rm e}\bar{\rm b}{\rm b}\bar{\rm b}{\rm b}$ at the LHC, which is an irreducible background to ${\rm p}{\rm p}\to{\rm t}\bar{\rm t}{\rm H}\bigl(\to{\rm b}\bar{\rm b}\bigr)$. This is the first time that a full NLO computation for a $2\to8$ process with 6 external strongly-interacting partons is made public. No approximations are used, and all off-shell and interference effects are taken into account. Cross sections and differential distributions from the full computation are compared to results obtained by using a double-pole approximation for the top quarks. The difference between the full calculation and the one using the double-pole approximation is in general below 5\% but can reach 10\% in some regions of phase space.

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Ansgar Denner, Jean-Nicolas Lang, Mathieu Pellen. 2020-08-03. Full NLO QCD corrections to off-shell ttbb production. https://doi.org/10.1103/physrevd.104.056018

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