Some models of particle-nucleus interactions

At the current level of understanding of the processes which take place when particles interact with nuclei, it is useful to establish at least a rough classification of the existing extreme points of view. One sometimes speaks of a single-stage or two-stage development of aA interaction processes. The first case includes, for example, the multiperipheral model, and the second includes the production and decay of hadron clusters. Such a classification does not seem entirely satisfactory. Indeed, the multiperipheral model and its parton interpretation do not have a single-stage character; in this model, there is clar manifestation of the space-time development of the process: the decay of a hadron into virtual (or real) groups of partons (hadrons); the interaction of slow particles of this group with the nucleus; and the production of secondary hadrons as a result of the assembly or fragmentation of the virtual particles (partons)