Evolution of a spallation reaction: experiment and Monte Carlo simulation

Reaction cross sections and production cross sections for neutrons, hydroge n, and helium have been measured for 1.2, 1.8 GeV p+Fe, Ni, Ag, Ta, W, Au, Pb and U and are compared with different intra-nuclear-cascade- combined wi th evaporation-models. Agreement for neutrons and considerable differences for light charged particles are observed between experiment and calculation as well as between different models. The discrepancies are associated with specific deficiencies in the models. The exclusive data measured with two 4 pi-detectors for neutron and charged particle detection allowed furthermo re a systematic comparison of observables characteristic of different stage s of the temporal evolution of a spallation reaction: inelastic collision p robability, excitation energy distribution, pre-equilibrium emission, and i nclusive production cross sections. (C) 1999 Elsevier Science B.V. All righ ts reserved.