Evaluation of primary radiation damage cross sections with uncertainties for charged particles

Abstract

Radiation damage is an important challenge for materials employed in strong irradiation environments, such as nuclear reactors and accelerators. The radiation damage is often quantified by the primary radiation damage with the unit of displacement per atom (dpa). To more accurately estimate the displacement damage, the athermal recombination-corrected (arc)-dpa model has been proposed by adding an efficiency function in the standard Norgett-Robinson-Torrens (NRT)-dpa model. Since the arc-dpa model is proposed based on pure atomistic simulations, the present work determines and validates the model parameters against experimental data of proton, deuteron, and alpha-particle irradiation for 13 materials. Besides the optimized values, the 1σ reasonable regions are determined for the model parameters. The corresponding dpa cross sections and the propagated uncertainties are in good agreement with the experimental data for 12 materials, while either experimental measurements or the current arc-dpa model is questionable for Ta. The experimentally validated arc-dpa model parameters can be used in other applications. It is noticeable that the distribution of the damage cross section is not necessarily Gaussian, or even not symmetrical. Thus, both the positive and negative deviations are determined. Moreover, the complete correlation matrices of dpa cross sections are also determined for further uncertainty estimation of displacement damage.