General-purpose event generators for LHC physics

Andy Buckley, Jonathan Butterworth, Stefan Gieseke, David Grellscheid, Stefan Höche, Hendrik Hoeth, Frank Krauss, Leif Lönnblad, Emily Nurse, Peter Richardson, Steffen Schumann, Michael H. Seymour, Torbjörn Sjöstrand, Peter Skands, Bryan R Webber

Research output: Contribution to journalReview ArticleResearchpeer-review

289 Citations (Scopus)


We review the physics basis, main features and use of general-purpose Monte Carlo event generators for the simulation of proton-proton collisions at the Large Hadron Collider. Topics included are: the generation of hard scattering matrix elements for processes of interest, at both leading and next-to-leading QCD perturbative order; their matching to approximate treatments of higher orders based on the showering approximation; the parton and dipole shower formulations; parton distribution functions for event generators; non-perturbative aspects such as soft QCD collisions, the underlying event and diffractive processes; the string and cluster models for hadron formation; the treatment of hadron and tau decays; the inclusion of QED radiation and beyond Standard Model processes. We describe the principal features of the Ariadne, Herwig++, Pythia 8 and Sherpa generators, together with the Rivet and Professor validation and tuning tools, and discuss the physics philosophy behind the proper use of these generators and tools. This review is aimed at phenomenologists wishing to understand better how parton-level predictions are translated into hadron-level events as well as experimentalists seeking a deeper insight into the tools available for signal and background simulation at the LHC.

Original languageEnglish
Pages (from-to)145-233
Number of pages89
JournalPhysics Reports
Issue number5
Publication statusPublished - Jul 2011
Externally publishedYes


  • Hadron colliders
  • Monte Carlo simulation
  • QCD

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