Peripheral fragmentation of relativistic nuclei

The modern concepts of nucleon clustering are described in brief. The application of experimental methods of relativistic nuclear physics for the development of nucleon cluster physics is presented. A short review of research performed by the nuclear emulsion technique is given. The significance of observations of coherent dissociation of relativistic nuclei for the study of nuclear clustering is discussed. According to observations in nuclear emulsion, the degree of coherent dissociation may reach complete dissociation both for light nuclei O, Ne, Mg and Si, and for heavy nuclei Au, Pb and U. This phenomenon may be a source of cluster systems of unprecedented complexity. Pattern of coherent dissociation for a large variety of nuclei, adjacent to the beginning of the table of isotopes, including radioactive ones, is studied