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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ArXiv ePrint: 1207.5031
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Gehrmann, T., Höche, S., Krauss, F. et al. NLO QCD matrix elements + parton showers in e+e− → hadrons. J. High Energ. Phys. 2013, 144 (2013). https://doi.org/10.1007/JHEP01(2013)144
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DOI: https://doi.org/10.1007/JHEP01(2013)144