HIGH-ENERGY-PHYSICS EVENT GENERATION WITH PYTHIA-5.7 AND JETSET-7.4

PYTHIA and JETSETare the two main components of the ''Lund Monte Carlo '' program suite. They can be used to generate high-energy-physics ''e vents'', i.e. sets of outgoing particles produced in the interactions between two incoming particles. Ideally these events should have the s ame average behaviour and the same fluctuations as real data. The unde rlying physics is not understood well enough to give an exact descript ion, the programs therefore contain a combination of analytical result s and various models. Several event classes are considered, within and beyond the standard model. We give a summary of the main physics comp onent of the current versions, PYTHIA 5.7 and JETSET 7.4: hard-scatter ing matrix elements, parton distributions, initial- and final-state ra diation, multiple interactions, beam remnants. fragmentation and decay s. A brief outline is also given of some programming aspects. A detail ed physics description and manual is available as a separate publicati on.