MSTAR2019: Uranium Enrichment Cascades With Sidestreams

The MSTAR2019 code, an ideal cascade model of uranium enrichment that includes sidestreams, has recently been delivered to the environmental sampling unit at the IAEA. The code builds on previous versions of the MSTAR code, but now includes options for a side feed and/or side product streams. Based on equations derived by Ed Von Halle, the current version includes several additional features such as flexible input options and integer numbers of stages. A number of applications are demonstrated that are relevant to safeguards analysis of enrichment plants, including enrichment of natural uranium to reactor fuel or to high enrichments, enrichment of recycled uranium, and various simulations of undeclared operations. Finally, this work describes limitations of ideal cascade models generally and discusses unusual situations and how they could be simulated using this code.