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arXiv · hep-ph/0204244

Matching NLO QCD computations and parton shower simulations

S. Frixione·B. R. Webber
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Abstract

We propose a method for matching the next-to-leading order (NLO) calculation of a given QCD process with a parton shower Monte Carlo (MC) simulation. The method has the following features: fully exclusive events are generated, with hadronization according to the MC model; total exclusive rates are accurate to NLO; NLO results for distributions are recovered upon expansion in $α_S$; 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; and matching between the hard- and soft/collinear-emission regions is smooth. A fraction of events with negative weight is generated, but unweighting remains possible with reasonable efficiency. The method is clarified using a simple toy model, and illustrated by application to the hadroproduction of W$^+$W$^-$ pairs.

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S. Frixione, B. R. Webber. 2002-07-12. Matching NLO QCD computations and parton shower simulations. https://doi.org/10.1088/1126-6708%2F2002%2F06%2F029

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