Jet vetoing and Herwig++

  • Alex Schofield
  • Michael H. Seymour


We investigate the simulation of events with gaps between jets with a veto on additional radiation in the gap in Herwig++. We discover that the currently-used random treatment of radiation in the parton shower is generating some unphysical behaviour for wide-angle gluon emission in QCD 2 → 2 scatterings. We explore this behaviour quantitatively by making the same assumptions as the parton shower in the analytical calculation. We then modify the parton shower algorithm in order to correct the simulation of QCD radiation.


Jets Hadronic Colliders QCD 


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Copyright information

© SISSA, Trieste, Italy 2012

Authors and Affiliations

  1. 1.School of Physics & AstronomyUniversity of ManchesterManchesterU. K.

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