The Influence of the Fissioning Nuclei Characteristics on the Parameters of Smoothed Dependence of Fission Rate on Time

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Abstract:

This paper discusses the influence of the basic parameters of the nuclear fission process modeling on the smoothed dependence of fission rate on time. As the main fissioning nuclei parameters in this study, the author considers the excitation energy and the damping coefficient, which varied widely in the simulation. The simulation was performed on the example of nuclear fission of Thorium-220 using two collective potentials that differ in the region of oblate forms of fissioning nuclei. The dependences of the average time of achievement by fission rate a half of its quasistationary value, as well as diffuseness of the smoothing function on friction coefficient for different excitation energies were calculated. It was found that these dependences can be approximately considerate as linear. The average values of angles tangent of the dependence also were calculated. It allowed to detect the presence of a significant correlation of the smoothing function parameters under consideration. Based on this conclusion, it is possible to link them analytically, without going beyond the permissible errors. In the future, an attempt will be made to replace the two discussed parameters with one generalized parameter that should make it easily to predict the type of smoothing function depending on the modeling parameters. The results are intended to be used to improve statistical models of nuclear fission in order to improve the realism of calculations and the accuracy of the results.

References:

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