Using external ion irradiations for simulating self-irradiation damage in nuclear waste glasses: State of the art, recommendations and, prospects

Due to the complexities associated with handling and characterizing the radiation damage in radioactive materials such as nuclear waste forms, ion irradiation has been widely used to simulate the effects of the self-irradiation damage. This often involves ion irradiation of nuclear waste surrogate glasses using ion accelerators. Such facilities allow using a wide range of ion types ranging from H to U and energies from tens of keV to hundreds of MeV. For various reasons, the researchers often have to use ions and energies that do not necessarily match with what is expected in actual nuclear waste forms. Due to a lack of detailed and dedicated studies, there are currently no guidelines or consensus regarding the use of the ion irradiation as a means of simulating the self-irradiation damage. The purpose of this article is to delve into this subject by presenting systematic studies of a number of glasses carried out in the last decade or so. By doing so, guidelines and easy to follow ion-mass Vs ion energy contour maps are provided to best simulate the long-term radiation damage in nuclear waste forms. We also discuss how the ions of different masses and energies can be exploited for defect healing and provide a roadmap to undertake systematic studies on this subject. For the sake of brevity, a quick summary of the important results and the guidelines is presented towards the end of this article and not here. Besides the nuclear waste community, the study is also of interest to a wide research community dealing with defect formation and defect healing in glasses for use in radiation environments experienced in nuclear reactors, decommissioning and space applications to name a few.