Multidimensional stochastic approach to fission dynamics of excited nuclei

The results of calculations of mass-energy, charge and angular fission fragments distributions from excited compound nuclei in the wide range of the fissility parameter and excitation energy are reviewed. The review covers recent developments and achievements of multidimensional stochastic approach to fission dynamics that were made during the last five years. The calculations are carried out mainly within the stochastic approach based on three-dimensional Langevin equations. Evaporation of prescission light particles along Langevin trajectories from the ground state of compound nucleus to scission has been taken into account using a statistical model. The temperature-dependent finite-range liquid-drop model is used in a consistent way to calculate the potential energy and level-density parameter of fissioning nucleus. The modified one-body mechanism for nuclear dissipation with reduction coefficient of the contribution from wall formula has been employed to calculate the friction tensor. The comparison of obtained results and experimental data shows that not only characteristics of mass-energy distribution, but also the mass and kinetic-energy dependence of prescission and postscission neutron multiplicities, the angular anisotropy and fission probability can be reproduced using surface-plus-window dissipation with the reduction coefficient from a wall formula ks 0.25-0.5. The problems which should be solved for further development of the multidimensional stochastic approach to fission dynamics are discussed