AUTHOR=Raposio Robert , Braoudakis George , Rosenfeld Anatoly , Bedwell-Wilson Juniper , Thorogood Gordon TITLE=Investigating 99Mo output changes in high-sustainability uranium targets by modifying target volume and geometry JOURNAL=Frontiers in Nuclear Engineering VOLUME=2 YEAR=2023 URL=https://www.frontiersin.org/journals/nuclear-engineering/articles/10.3389/fnuen.2023.978990 DOI=10.3389/fnuen.2023.978990 ISSN=2813-3412 ABSTRACT=

Introduction: The most common current uranium target type for ⁹⁹Mo production uses plate geometry. This paper investigates the effects of geometry on ⁹⁹Mo output and target sustainability.

Methods: MCNP6.2 was used to model rectangular, spherical, and cylindrical targets ranging from 12.03 cm³ to 120.34 cm³ to determine the target geometry and volume effects on 99Mo output, sustainability, proliferation concerns, and heating. 4-7 days irradiation was used with a consistent target density of 2 g/cm³ UO₂ for all target types.

Results and Discussion: The cylindrical target was found to have the best performance due to having the second highest sustainability, the highest ⁹⁹Mo output and produce the lowest amounts of ²³⁹Pu compared to the other target geometries. The heating comparison showed that there were negligible heating concerns for all target volumes and geometries.