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arXiv · 2309.17353

Modelling uncertainties and prompt b-jet identification in $t\bar{t}b\bar{b}$ production with dilepton signatures at the LHC

Giuseppe Bevilacqua
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Abstract

As one of the primary backgrounds to $pp \to t\bar{t}H(H\to b\bar{b})$, the QCD process of $t\bar{t}b\bar{b}$ hadroproduction demands very accurate theoretical predictions and estimates of uncertainties. On top of that, the capacity of properly identifying prompt $b$-jets is beneficial for many analyses. In this contribution we discuss state-of-the-art predictions for $t\bar{t}b\bar{b}$ production with dilepton decays at the LHC, as obtained from full off-shell NLO QCD calculations. We evaluate the dominant uncertainties of the calculation and the impact of the off-shell effects on fiducial cross sections. Furthermore, we explore a kinematic prescription for the categorisation of prompt $b$-jets.

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Giuseppe Bevilacqua. 2023-09-29. Modelling uncertainties and prompt b-jet identification in $t\bar{t}b\bar{b}$ production with dilepton signatures at the LHC. https://arxiv.org/abs/2309.17353

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