Chiral invariant phase space event generator - I. Nucleon-antinucleon annihilation at rest

The CHIPS model and its first implementation within the GEANT4 simulation software package are considered. Hadron production in the process of nucleon-antinucleon annihilation is used as the basic example showing the structure of the model and corresponding software modeling algorithms. Model calculations of multiplicities and spectra of secondary hadrons in the annihilation process are compared with experimental data.