QCD matrix elements + parton showers. The NLO case

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


We present a process-independent technique to consistently combine next-to-leading order parton-level calculations of varying jet multiplicity and parton showers. Double counting is avoided by means of a modified truncated shower scheme. This method preserves both the fixed-order accuracy of the parton-level result and the logarithmic accuracy of the parton shower. We discuss the renormalisation and factorisation scale dependence of the approach and present results from an automated implementation in the SHERPA event generator using the test case of W -boson production at the Large Hadron Collider. We observe a dramatic reduction of theoretical uncertainties compared to existing methods which underlines the predictive power of our novel technique.


Monte Carlo Simulations NLO Computations 


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Copyright information

© SISSA 2013

Authors and Affiliations

  • Stefan Höche
    • 1
  • Frank Krauss
    • 2
  • Marek Schönherr
    • 2
  • Frank Siegert
    • 3
  1. 1.SLAC National Accelerator LaboratoryMenlo ParkU.S.A
  2. 2.Institute for Particle Physics PhenomenologyDurham UniversityDurhamU.K
  3. 3.Physikalisches InstitutAlbert-Ludwigs-Universität FreiburgFreiburgGermany

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