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Implementing NLO DGLAP evolution in parton showers

  • Stefan Höche
  • Frank Krauss
  • Stefan Prestel
Open Access
Regular Article - Theoretical Physics

Abstract

We present a parton shower which implements the DGLAP evolution of parton densities and fragmentation functions at next-to-leading order precision up to effects stemming from local four-momentum conservation. The Monte-Carlo simulation is based on including next-to-leading order collinear splitting functions in an existing parton shower and combining their soft enhanced contributions with the corresponding terms at leading order. Soft double counting is avoided by matching to the soft eikonal. Example results from two independent realizations of the algorithm, implemented in the two event generation frameworks Pythia and Sherpa, illustrate the improved precision of the new formalism.

Keywords

Jets QCD Phenomenology 

Notes

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

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Copyright information

© The Author(s) 2017

Authors and Affiliations

  1. 1.SLAC National Accelerator LaboratoryMenlo ParkU.S.A.
  2. 2.Institute for Particle Physics PhenomenologyDurham UniversityDurhamU.K.
  3. 3.Fermi National Accelerator LaboratoryBataviaU.S.A.

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