Matching NLO QCD and parton showers in heavy flavour production

We apply the MC@NLO approach to the process of heavy flavour hadroproduction. MC@NLO is a method for matching next-to-leading order (NLO) QCD calculations and parton shower Monte Carlo (MC) simulations, with the following features: fully exclusive events are generated, with hadronisation according to the MC model; total rates are accurate to NLO; NLO results for distributions are recovered upon expansion in αS; hard emissions are treated as in NLO computations while soft/collinear emissions are handled by the MC simulation, with the same logarithmic accuracy as the MC; matching between the hard and soft regions is smooth, and no intermediate integration steps are necessary. The method was applied previously to the hadroproduction of gauge boson pairs, which at NLO involves only initial-state QCD radiation and a unique colour structure. In heavy flavour production, it is necessary to include contributions from final-state QCD radiation and different colour flows. We present illustrative results on top and bottom production at the Tevatron and LHC.

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