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arXiv · 1207.5031

NLO QCD matrix elements + parton showers in e+e- -> hadrons

Thomas Gehrmann·Stefan Hoeche·Frank Krauss·Marek Schonherr·Frank Siegert
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Abstract

We present a new approach to combine multiple NLO parton-level calculations matched to parton showers into a single inclusive event sample. The method provides a description of hard multi-jet configurations at next-to leading order in the perturbative expansion of QCD, and it is supplemented with the all-orders resummed modelling of jet fragmentation provided by the parton shower. The formal accuracy of this technique is discussed in detail, invoking the example of electron-positron annihilation into hadrons. We focus on the effect of renormalisation scale variations in particular. Comparison with experimental data from LEP underlines that this novel formalism describes data with a theoretical accuracy that has hitherto not been achieved in standard Monte Carlo event generators.

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Thomas Gehrmann, Stefan Hoeche, Frank Krauss, Marek Schonherr, Frank Siegert. 2013-02-13. NLO QCD matrix elements + parton showers in e+e- -> hadrons. https://doi.org/10.1007/jhep01(2013)144

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