Momentum Transfer in Heavy-Ion-Induced Fission

The forward linear momentum transfer in reactions leading to fission between heavy ions such as C/sup 12/, N/sup 14/, O/sup 16/, and Ne/sup 20/ and the target nuclei Ho, Au, Bi, and U/sup 238/ was investigatad by measuring the angular correlation between the fragments. The experimental values for the most probable parameters for center-of-mass transformation for these systems are compared with calculated values. For all the systems, the dominant reaction involves a full momentum transfer by the heavy ion to the fissioning nucleus. It is observed that for the system Au + Ne/sup 20/ and Bi + Ne/sip 20/, reactions with incomplete momentum deposition contribute 5.1% and 8.6%, respectively, to the total fission cross section. For U/sup 238/ targets, this admixture amounts to 12 to 17% for all ions at the highest bombarding energy and decreases with decreasing projectile energy. Possible reaction mechanisms leading to fission are suggested. A brief discussion of the method and its application is given. (auth)