Calculation of the moments of the fission-fragment energy distribution by the method of Langevin equations

The energy distribution of the fission fragments of excited nuclei is described from the standpoint of a fluctuation dissipation dynamics based on Langevin equations. It is shown that the existing diffusion model, which uses the Fokker-Planck equation, works satisfactorily in its range of applicability. The moments of the fragment energy distribution (the mean value, the variance, the skewness, and the kurtosis) are calculated systematically for nuclei with 54 < Z < 104. The results are compared with the available experimental systematics. 25 refs., 7 figs