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The isotope 232 U is being considered for additive to uranium fuel for use as a tracer. The 232 U decay chain has high energy gammas that can be used for tracer purposes. However, the presence and intensity of such gammas may increase effective dose rates to workers around such materials This study examines the dose rate from different uranium materials that varying amounts of 232 U has been added to. Several materials and their respective storage geometries are modeled for particle transport calculations. For each material and 232 U concentration, gamma source terms were generated using SCALE 6.2 ORIGEN. These source terms were then used in MCNP for each material and geometry. Upon analysis, it was determined that the baseline dose from enriched uranium dominates until the 232 U concentration reaches about 10-100 parts per trillion (ppt), after which the dose rate increases linearly., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

This study examines the production of 232 U via neutron irradiation. Uranium-232 is considered for use as a tracer in nuclear fuel. However, a source of 232 U is needed. This study examines the production of 232 U via neutron irradiation of targets constructed out of either 231 Pa or 230 Th in the High Flux Isotope Reactor. HFIR targets were modeled in MCNP to determine 232 U yield in protactinium and thorium targets. Flux tallies were used inside the targets to determine the neutron flux inside each target. This flux was then used in SCALE 6.2 ORIGEN to determine the 232 U yield, as well as the buildup of the byproduct 233 U. Several 230 Th enrichments were examined to determine how 232 U yield is affected by 230 Th enrichment, as well as the effects of the presence of 232 Th. The buildup of 228 Th and 229 Th in thorium targets was also examined, as these isotopes may impact the feasibility of recycling of thorium target materials., (Copyright © 2022 Elsevier Ltd. All rights reserved.)