An analytic initial-state parton shower

  • Wolfgang Kilian
  • Jürgen Reuter
  • Sebastian Schmidt
  • Daniel Wiesler
Open Access


We present a new algorithm for an analytic parton shower. While the algorithm for the final-state shower has been known in the literature, the construction of an initialstate shower along these lines is new. The aim is to have a parton shower algorithm for which the full analytic form of the probability distribution for all branchings is known. For these parton shower algorithms it is therefore possible to calculate the probability for a given event to be generated, providing the potential to reweight the event after the simulation. We develop the algorithm for this shower including scale choices and angular ordering. Merging to matrix elements is used to describe high-energy tails of distributions correctly. Finally, we compare our results with those of other parton showers and with experimental data from LEP, Tevatron and LHC.


Jets Hadronic Colliders QCD NLO Computations 


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Copyright information

© SISSA, Trieste, Italy 2012

Authors and Affiliations

  • Wolfgang Kilian
    • 1
  • Jürgen Reuter
    • 2
  • Sebastian Schmidt
    • 2
  • Daniel Wiesler
    • 2
  1. 1.Department PhysikUniversität SiegenSiegenGermany
  2. 2.DESY Theory GroupHamburgGermany

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