A quantitative analysis of an in situ Xe ion implantation experiment on single crystal molybdenum via a molecular dynamics informed kinetic rate theory simulation

Kinetic rate theory is a mature method that has long been used to model fission gas behaviors in nuclear fuels. However, uncertainties remaining in the key parameters of the kinetic rate theory models often lead to doubts in the accuracy of this method. In this work, the results of an in situ Xe ion implantation experiment at the IVEM facility were interpreted via a Molecular Dynamics (MD) informed kinetic rate theory simulation. The complexity of the rate theory model is significantly reduced according to some key experimental information. The MD method was used to supply the irradiation-enhanced Xe diffusion coefficient to the rate theory model. The bubble nucleation factor and the bubble resolution coefficient were also determined. A parametric study was performed to gauge the sensitivity of the calculation results to the distribution of the irradiation-enhanced Xe diffusion coefficient, the value of the bubble nucleation factor, and the resolution coefficient. It was shown that the calculated bubble size distribution is highly sensitive to all these parameters.