Induced fission studies of Z\textless 82 at the JAEA tandem facility

Recent beta-delayed fission studies of proton rich $^{180}$Hg showed the fission to be dominated by asymmetric fragment masses, in contrast to initial predictions. Models of the potential-energy surface for the path toward scission showed a lower fission barrier for an asymmetrically deformed $^{180}$Hg volume. As a probe of this theoretical interpretation, fission of $^{180}$Hg was induced through the symmetric reaction $^{90}$Z$+^{90}$Z. Mass and energy distributions of fragments for a series of bombarding energies were recorded using 2 MWPCs. As a continuation of Z $<82$ fission studies, fission induced in the $^{7}$Li$+^{182,184,186}$W reactions were measured. Near A$\sim$190 a new region of asymmetric fission is predicted to emerge as one moves towards neutron rich nuclei. In preliminary investigations mass asymmetry was observed in fragments of the $^{7}$Li$+^{186}$W reaction. However, fragment kinematics were inconsistent with fission of $^{193}$Ir formed by fusion. A follow up experiment was conducted in an attempt to confirm the first observation of fission induced by the $^{7}$Li breakup-fusion reaction $^{186}$W$(^{7}$Li,$^{4}$He$)^{189}$Re. Experimental details and initial results will be presented.