DESY 96-057 ISSN 0418-9833
April 1996 LEPTO 6.5 -- A Monte Carlo Generator
for Deep Inelastic Lepton-Nucleon Scattering

G. Ingelman , A. Edin , J. Rathsman

ingelman@desy.de      rathsman@tsl.uu.se      edin@tsl.uu.se
Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, D-22603 Hamburg, FRG
Dept. of Radiation Sciences, Uppsala University, Box 535, S-751 21 Uppsala, Sweden

Abstract. Physics and programming aspects are discussed for a Fortran 77 Monte Carlo program to simulate complete events in deep inelastic lepton-nucleon scattering. The parton level interaction is based on the standard model electroweak cross sections, which are fully implemented in leading order for any lepton of arbitrary polarization, and different parametrizations of parton density functions can be used. First order QCD matrix elements for gluon radiation and boson-gluon fusion are implemented and higher order QCD radiation is treated using parton showers. Hadronization is performed using the Lund string model, implemented in JETSET/PYTHIA. Rapidity gap events are generated through a model based on soft colour interactions.

• Introduction
• Physics and MC implementation
  • Kinematics
  • Electroweak cross sections
  • Longitudinal structure function
  • Parton density distributions
  • First order QCD processes
  • QCD parton shower evolution
  • Nucleon remnant and hadronization
  • Soft colour interactions and rapidity gaps
• Description of program components
  • Subroutines and functions
  • Common blocks
• Usage and availability
• References
• About this document ...