STUDY OF HIGH-LYING CLUSTER STATES OF NUCLEI BY THE METHOD OF PARTICLE-PARTICLE ANGULAR-CORRELATIONS

The current status of research on nuclear reactions induced by light a nd semiheavy ions of energy up to 10 MeV/nucleon on light and intermed iate nuclei by measurement of the angular correlation functions of the final products is reviewed. The principal theoretical and experimenta l studies on particle-particle correlations carried out in recent year s are analyzed. The methods of calculating the angular correlation fun ctions and the spin tensors of the reaction-product density matrix for reactions involving excited states using the distorted-wave method wi th finite interaction range and the modified compound-nucleus model ar e described. The alpha-d and alpha-t correlations in reactions involvi ng Li-6,Li-7 and N-14 ions are analyzed. The highly excited alpha-clus ter states in C-12, O-16, Ne-20, and Mg-24 are studied. The polarizati on tensors of the Li-6 nucleus in the 3(+) state are calculated and co mpared with experiment. It is shown that the particle-particle angular correlation functions and the polarization tensors can provide unique information about the reaction mechanism and about the structure of t he wave functions of highly excited nuclear states, including the natu re of the radial dependence in the interior of the nucleus and the opt ical interaction potentials in the entrance and exit reaction channels , and so on. This review can be useful for both theoreticians and expe rimentalists working on the physics of nuclear reactions involving par ticles of moderate energy. (C) 1998 American Institute of Physics.