EMISSION OF INTERMEDIATE-MASS FRAGMENTS DURING FISSION

Ternary fission in the reaction He-4 + Th-232 at E(lab)=200 MeV has be en observed. Intermediate mass fragments (IMF: 3 less than or equal to Z less than or equal to 8) with unique energy and angular distributio ns have been measured consistent with emission from the neck zone duri ng fission. The widths of the energy spectra are relatively constant f or neck fragments with Z greater than or equal to 4, suggesting little variability in the scission configurations. A linear dependence of [E ] on Z is observed for the neck IMFs. The observed trend is compared w ith a Coulomb trajectory model.