1 The SPALADIN experiment at GSI

1) Interest of the study of spallation reactions for basic nuclear physics Heavy-ion collisions in the GeV per nucleon range involve different and mixed mechanisms. The phenomena at play in theses collisions occur on different energy scales, from a few 100 MeV for the first nucleon-nucleon collisions to a few 100 keV for de-excitation photon emission at the end of the reactions when the excitation of the interacting systems is below the nucleon emission thresholds. A quantum calculation of a reaction involving two nuclei of mass numbers A1 and A2 from first principles would require the determination of the time dependence of a A1 * A2 nucleon wave function with relativistic nucleons in the first instants of the reaction, with particle production (mainly pions) from inelastic nucleon-nucleon collisions. Such a calculation is not feasible. For this reason, the calculations of these reactions have been modeled in a three-step process corresponding to three different ranges of the exchanged energy at the nucleon level:- Fast individual nucleon-nucleon scattering as the first step of the collisions, with exchanged energies in the range going from a few 10 to a few 100 MeV, including elastic and inelastic channels of the nucleon-nucleon cross-section,- Pre-equilibrium stage where fast particles are emitted, energies involved being of the order of 10 MeV,- Evaporation in competition with fission for heavy nuclei, with energies in the Me