Three-dimensional Langevin approach to kinetic energy and mass distribution of fission-fragments

A three-dimensional Langevin equation with covariant form is applied to des cribe the asymmetric nuclear fission. The calculations for kinetic energy a nd mass distribution of fission-fragments are performed in terms of the {c, h, alpha} parameterization, and the descent process of the fissioning nucl eus from the saddle point to the scission point is simulated numerically. T he dependence of the model on the choices for two types of nuclear dissipat ion such as two-body viscosity and one-body dissipation, as well as the sci ssion configurations of nuclear system with finite neck is investigated.