Speaker
Description
As one of the primary sources of QCD background to $pp \to t\bar{t}H(H\to b\bar{b})$ at the LHC, the $t\bar{t}b\bar{b}$ production process demands precise theoretical predictions and estimates of the dominant uncertainties. On top of that, the capacity of properly disentangling the prompt b-jets and the b-jets from top-quark decays has important phenomenological consequences. In this talk we present state-of-the-art predictions for ttbb production with dilepton decays at the LHC as obtained from a full off-shell calculation at NLO QCD accuracy. We discuss the dominant theory uncertainties, assess the relevance of double-, single- and non-resonant contributions and investigate the impact of different b-jet definitions on the cross section. Finally we present a kinematics-based prescription to cope with the identification of the prompt b-jets.
