Abstract
We report on the calculation of the next-to-leading order QCD corrections to the production of a toverline{t} pair in association with two heavy-flavour jets. We concentrate on the di-lepton toverline{t} decay channel at the LHC with sqrt{s} = 13 TeV. The computation is based on pp → e+νeμ− overline{nu} μ boverline{b}boverline{b} matrix elements and includes all resonant and non-resonant diagrams, interferences and off-shell effects of the top quark and the W gauge boson. As it is customary for such studies, results are presented in the form of inclusive and differential fiducial cross sections. We extensively investigate the dependence of our results upon variation of renormalisation and factorisation scales and parton distribution functions in the quest for an accurate estimate of the theoretical uncertainties. We additionally study the impact of the contributions induced by the bottom-quark parton density. Results presented here are particularly relevant for measurements of toverline{t}H (H → boverline{b} ) and the determination of the Higgs coupling to the top quark. In addition, they might be used for precise measurements of the top-quark fiducial cross sections and to investigate top-quark decay modelling at the LHC.
Highlights
The computation is based on pp → e+νe μ−νμ bb bb matrix elements and includes all resonant and non-resonant diagrams, interferences and off-shell effects of the top quark and the W gauge boson. As it is customary for such studies, results are presented in the form of inclusive and differential fiducial cross sections
Results presented here are relevant for measurements of ttH(H → bb) and the determination of the Higgs coupling to the top quark. They might be used for precise measurements of the top-quark fiducial cross sections and to investigate top-quark decay modelling at the LHC
We show various theoretical predictions for ttbb production that have been used in ref. [23] to compare with the ATLAS data
Summary
The computation is based on pp → e+νe μ−νμ bb bb matrix elements and includes all resonant and non-resonant diagrams, interferences and off-shell effects of the top quark and the W gauge boson As it is customary for such studies, results are presented in the form of inclusive and differential fiducial cross sections. Calculations at NLO in QCD are available for stable top quarks already for some time [10,11,12,13,14,15] They suffer from large uncertainties in the choice of factorisation and renormalisation scales that are of the order of 33% and large NLO corrections of the order of 77%. Generally speaking, the pp → ttbbj process at NLO entails information that can be used to gain some insights into the perturbative convergence of the inclusive ttbb cross section beyond NLO
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
