2 DEFORMATION PATHS IN PROTON-INDUCED FISSION OF TH-232

Velocities of complementary fission fragments have been accurately mea sured by a double velocity time-of-flight method in the proton-induced fission of Th-232 with incident energies from 12.0 to 14.7 MeV, The r esults experimentally demonstrate for the first time the correlation a mong the threshold energy, the total fragment kinetic energy, and the mass division mode in fission: one type of the fission process has a l ower threshold energy and lends to a compact scission configuration wi th reflection asymmetry, and the other type has a higher threshold ene rgy and leads to a symmetric elongated scission configuration.