Optimization of Deuteron Irradiation of Yb for Producing Lu of High Specific Activity Exceeding 3000 GBq/mg.

The irradiation of Yb with deuterons offers a promising pathway for the production of the theranostic radionuclide Lu. To optimize this process, calculations integrating deuteron transport, isotope production, and decay have been performed. In pure Yb, the undesired production of Lu occurs at higher deuteron energies, corresponding to a distribution slightly shallower than that of Lu. Hence, Lu can be effectively filtered out by employing either a low-energy deuteron beam or stacked foils. The utilization of stacked foils enables the production of Lu using a high-energy linear accelerator. Another unwanted isotope, Lu, is produced roughly at the same depth as Lu, but its concentration can be significantly reduced by selecting an appropriate post-irradiation processing time, owing to its relatively short half-life. The modeling approach extended to the mapping of yields as a function of irradiation time and post-irradiation processing time. An optimized processing time window was identified. The study demonstrates that a high-energy deuteron beam can be employed to produce Lu with high specific activity exceeding 3000 GBq/mg. The effect of different purity levels (ranging from 98% to 100%) was also discussed. The impurity levels have a slight impact. The modeling demonstrates the feasibility of obtaining Lu with a specific activity > 3000 GBq/mg and radionuclidic purity > 99.5% when using a commercially available Yb target of 99.6% purity.