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arXiv · 2203.05322

Semi-empirical model to determine pre- and post-neutron fission product yields and neutron multiplicity

Jounghwa Lee·Young-Ouk Lee·Tae-Sun Park·Peter Schillebeeckx·Seung-Woo Hong
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Abstract

Post-neutron emission fission product mass distributions are calculated by using pre-neutron emission fission product yields (FPYs) and neutron multiplicity. A semi-empirical model is used to calculate the pre-neutron FPY, first. Then the neutron multiplicity for each fission fragment mass is used to convert the pre-neutron FPY to the post-neutron FPY. In doing so, assumptions are made for the probability for a pre-emission fission fragment with a mass number $A^*$ to decay to a post-emission fragment with a mass number $A$. The resulting post-neutron FPYs are compared with the data available. The systems where the experimental data of not only the pre- and post-neutron FPY but also neutron multiplicity are available are the thermal neutron-induced fission of $^{233}$U, $^{235}$U and $^{239}$Pu. Thus, we applied the model calculations to these systems and compared the calculation results with those from the GEF and the data from the ENDF and the EXFOR libraries. Both the pre- and post-neutron fission product mass distributions calculated by using the semi-empirical model and the neutron multiplicity reproduce the overall features of the experimental data.

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Jounghwa Lee, Young-Ouk Lee, Tae-Sun Park, Peter Schillebeeckx, Seung-Woo Hong. 2022-03-10. Semi-empirical model to determine pre- and post-neutron fission product yields and neutron multiplicity. https://doi.org/10.1007/s40042-022-00490-2

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