Cumulative Processes and Fractal Structure of Nuclei

Selection of cumulative events is assumed to enrich data samples by a new type of collisions characterized by higher energy density and more compressed matter. We expect that this will allow finding more clear signatures of phase transition, location of a critical point and studying extreme conditions in heavy ion collisions. The brief review of z-scaling concept based on the principles of self-similarity, locality and fractality reflecting general features of particle interactions is given. The z-scaling was used to describe of particle production in cumulative and non-cumulative regions in p–A and A–A collisions. Structure of the colliding objects and fragmentation processes is characterized by the structural and fragmentation fractal dimensions. The produced medium is described by a “specific heat.” The results of data analysis of cumulative production in p–A and A–A collisions are discussed. The change of nucleus fractal dimension, fragmentation fractal dimension and specific heat near the critical point is considered as a signature of new physics.