Reaction valleys: two-center shell model in the study of complex nuclei

The two-center shell model and its application to nuclear fission and to heavy-ion collision problems is first briefly reviewed. Then, the extension of the asymmetric two-center shell model by introducing two new dynamical collective coordinates of mass and charge asymmetry are considered in the fragmentation theory. For fission, calculations are made for the mass- and charge-yield distributions with mass numbers from 250 to 292 for compound nuclei z=102-114 and for heavy-ion collisions, the mechanism of the compound nucleus formation, fusion-fission and the quasi-fission reactions is studied