Release:
2015, Vol. 1. №3(3)About the author:
Andrey L. Litnevsky, Cand. Sci. (Phys.-Math.), Omsk State Technical University; a_lit@list.ruAbstract:
Classical Kramers formulas for fission rate of excited nuclei are widely used in the combined modeling of this process. In the scientific literature there is evidence that when using these formulas, the fission rate can have uncontrolled errors, the size of which can reach 20% or even more. In this paper the relationship between the fission rate of the nuclei and their equilibrium distribution in the deformation coordinate is analyzed. Based on the results of the analysis performed, a correction to Kramers formulas that allows to reduce significantlly the error of analytically calculated fission rate for some collective potentials is introduced. The case of using the canonical ensemble in the model of fission is considered. Application of the proposed methodology to reach the agreement of Kramers and dynamical quasistationary fission rates will significantly reduce the errors of the combined simulation of nuclear fission.References:
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