Statistical Multifragmentation in Heavy-Ion Reactions: Theory and Experiments

In this chapter, the authors discuss nuclear multifragmentation, which is a universal phenomenon occurring when a large amount of energy is deposited in a nucleus. It has been observed in nearly all types of high-energy nuclear reactions induced by hadrons, photons, and heavy ions. At low excitation energies, the produced nuclear system can be treated as a compound nucleus, which decays via evaporation of light particles or fission. However, at high excitation energy, possibly accompanied by compression during the initial dynamical stage of the reaction, the system will expand to subsaturation densities, thereby becoming unstable, and will break up into many fragments. Multifragmentation is pronounced in case at least three intermediate mass fragments (IMFs) with Z = 3 are produced in one event. With the results of dynamical simulations as qualitative guidelines, the exact parameters of the thermalized sources are obtained from the analysis of the experimental fragmentation data.