hadronic event generator simulates the following subprocesses: Initial-state composition and substructure Initial-state showers The hard process Resonance decay Final-state showers Accompanying semi-hard processes Hadronization and further decay A typical heavy-ion event generator usually can be less strict in simulating the rare and rather negligible processes found in a hadronic generator, but would need to simulate the following subprocesses, in addition to those in a hadronic generator: Nuclear initial-state High multiplicity, soft processes In-medium energy loss Collective behavior of the medium (not handled properly by any generators so far) List of event generators The major event generators that are used by current experiments are: Hadronic event generators PYTHIA (formerly Pythia/Jetset) HERWIG ISAJET SHERPA Multi-purpose parton level generators MadGraph5 (able to run directly on the web site after registration and an email to the author) Whizard Heavy ion event generators GiBUU HIJING Neutrino event generators GENIE GiBUU NuWro Specialized event generators AcerMC – LHC background processes ALPGEN – multiple parton processes Ariadne – QCD cascade with Color Dipole Model MC@NLO – next-to-leading-order QCD matrix elements, using HERWIG for parton shower JIMMY – multiple parton processes STARlight – Photonuclear and two-photon processes in ultra-peripheral collisions of heavy ions GRANIITTI – Diffractive QCD and two-photon processes "Meta-generator" CompHEP – automatic evaluation of tree level matrix elements for event generation or export into other event generators References External links 2006 Monte Carlo Number Scheme, from the 2006 Review of Particle Physics. List of Monte Carlo Programs – from DESY Computational particle physics Monte Carlo methods