4 research outputs found
NLO QCD corrections to off-shell t t ¯ W ± production at the LHC: correlations and asymmetries
Abstract: Recent discrepancies between theoretical predictions and experimental data in multi-lepton plus b-jets analyses for the tt¯W± process, as reported by the ATLAS collaboration, have indicated that more accurate theoretical predictions and high precision observables are needed to constrain numerous new physics scenarios in this channel. To this end we employ NLO QCD computations with full off-shell top quark effects included to provide theoretical predictions for the R=σtt¯W+/σtt¯W- cross section ratio at the LHC with s=13 TeV. Depending on the transverse momentum cut on the b-jet we obtain 2–3% theoretical precision on R, which should help to shed some light on new physics effects that can reveal themselves only once sufficiently precise Standard Model theoretical predictions are available. Furthermore, triggered by these discrepancies we reexamine the charge asymmetry of the top quark and its decay products in the tt¯W± production process. In the case of charge asymmetries, that are uniquely sensitive to the chiral nature of possible new physics in this channel, theoretical uncertainties below 15% are obtained. Additionally, the impact of the top quark decay modelling is scrutinised by explicit comparison with predictions in the narrow-width approximation
Report of the Topical Group on Top quark physics and heavy flavor production for Snowmass 2021
This report summarizes the work of the Energy Frontier Topical Group on EW
Physics: Heavy flavor and top quark physics (EF03) of the 2021 Community Summer
Study (Snowmass). It aims to highlight the physics potential of top-quark
studies and heavy-flavor production processes (bottom and charm) at the HL-LHC
and possible future hadron and lepton colliders and running scenarios