CONSISTENT DYNAMIC AND STATISTICAL DESCRIPTION OF FISSION OF HOT NUCLEI

The modified approaches for a dynamical (Langevin) and a statistical d escription of fission of hot nuclei (based on entropy as the crucial q uantity) proposed in a forthcoming publication are shown to give consi stent values for fission rates in the framework of the liquid drop mod el for a wide range of excitation energies, angular momenta, and fissi lities. An approximate formula for the statistical fission rate is der ived which is more suitable for applications than the exact one. Contr ary to the conventional approach the new statistical description takes into account the positions of the stationary points (ground state and saddle points) of the entropy (not of the potential), and the positio n of the scission point. The fission rate calculated with the approxim ate formula deviates in all cases of interest by less than 25% from th e long-time limit of the dynamical (Langevin) fission rate. This is a clear improvement over the conventional model, where these deviations can be orders of magnitude.