Journal of High Energy Physics

, 2013:144 | Cite as

NLO QCD matrix elements + parton showers in e+e → hadrons

  • Thomas Gehrmann
  • Stefan Höche
  • Frank Krauss
  • Marek Schönherr
  • Frank Siegert
Open Access


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.


Monte Carlo Simulations NLO Computations 


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Copyright information

© SISSA 2013

Authors and Affiliations

  • Thomas Gehrmann
    • 1
  • Stefan Höche
    • 2
  • Frank Krauss
    • 3
  • Marek Schönherr
    • 3
  • Frank Siegert
    • 4
  1. 1.Institut für Theoretische PhysikUniversität ZürichZürichSwitzerland
  2. 2.SLAC National Accelerator LaboratoryMenlo ParkU.S.A
  3. 3.Institute for Particle Physics PhenomenologyDurham UniversityDurhamU.K
  4. 4.Physikalisches Institut, Albert-Ludwigs-Universität FreiburgFreiburgGermany

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