Deuteron-induced nuclear reactions to produce 177Lu: Extension of cross-sections data up to 33 MeV and impact on purity

Activation cross-sections of lutetium and ytterbium radionuclides have been measured by deuteron-induced nuclear reaction on ^natYb(d,x) at the GIP ARRONAX (Saint-Herblain, France) cyclotron facility with a beam energy up to 33 MeV using the stacked-foil activation technique combined with high resolution γ-ray spectrometry. The measured experimental values enable the extension of the cross-section to higher energies. As a primary objective, we have focused on the cumulative measurement of the direct and indirect production routes of the therapeutic radioisotope ^177gLu, via ¹⁷⁶Yb(d,n) ^177g,mLu and ¹⁷⁶Yb(d,p) ¹⁷⁷Yb →^177gLu respectively. Post-irradiation gamma analysis, including a long gamma counting period, was performed to calculate the yield of the undesirable metastable isotopic impurity ^177mLu. The results showed that it was found to be lower than our detection limit i.e. <0.0005% of ^177gLu yield. Thick target yields for all detected radionuclides are also calculated in this paper. These measurements enabled the estimation of the production yield and isotopic purity of ¹⁷⁷Lu obtained via deuteron-induced nuclear reactions for large production batches using highly enriched ¹⁷⁶Yb₂O₃ samples (>99.5%).