Document Type : Research paper
Authors
1 Faculty of Physics, University of Isfahan, 81746-73441, Isfahan, Iran
2 Faculty of Physics, University of Isfahan, 81746-73441, Isfahan, Iran Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, 141980 Dubna, Russia
Abstract
The nuclear fission of protactinium nuclei is a complex process influenced by an intricate interplay of nuclear components and microscopic details. This study presents a comprehensive analysis of the fission mechanism for 231-232Pa, emphasizing the role of parameters of fission barriers, static and dynamic deformations, predictions of nuclear level densities (NLD) models at the fission saddle points and its change compared to the ground state, fission models and fission dynamics. Through a combination of theoretical modeling and advanced simulation techniques using nuclear reaction and evaporation codes, the neutron induced fission cross sections of 231Pa are calculated and the profound impact of NLD on the static and dynamic deformations are illustrated. Our findings can be confirmed with experimental data which serve as benchmarks for the veracity of the proposed models. It is shown that the NLDs at saddle points have a significant effect on reaction results and fission path determination. It is shown that the effect of nuclear dynamic deformations should be included in the nuclear level density on the fission barriers so that the modeling can reproduce the experimental data. This study can be considered an essential roadmap for understanding the behavior of nuclear reactors and the development of nuclear energy.
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