[en] Excitation functions of the nuclear reactions ⁸⁵Rb(p, xn)^{85m,g,83,82,81}Sr and ¹²⁵Te(p, xn)^125,124,123I were measured from their respective thresholds up to 100 MeV using the stacked-foil technique. Thin samples of 99.4% enriched ⁸⁵RbCl were prepared by sedimentation on Cu-backing, and those of 98.3% enriched ¹²⁵Te by electrolytic deposition on Ti-backing. From the measured cross sections, integral yields of product radionuclides were calculated. The energy range E_p=37 → 30 MeV appears to be very suitable for production of the potentially interesting positron emitter ⁸³Sr via the ⁸⁵Rb(p, 3n) reaction; its thick target yield amounts to about 160 MBq/μA·h and the longer-lived ^82,85gSr impurities to < 0.25 %. Similarly the energy range E_p = 21 → 15 MeV is ideal for production of the important positron emitter ¹²⁴I via the ¹²⁵Te(p, 2n) process; its yield amounts to 81 MBq/μA·h and the level of the long-lived ¹²⁵I-impurity to 0.9 %. The two intermediate energy reactions thus provide good quality ⁸³Sr and ¹²⁴I in sufficient quantities. (author)

[en] Highlights: • Chromatographic recovery of medical isotope ¹¹¹Ag from proton irradiated thorium targets. • First-time measured equilibrium distribution coefficients for silver and ruthenium on CL resin. • ²³²Th (p, fission) cross-section data for the formation of ¹¹¹Ag and ^110mAg. - Abstract: Column chromatographic methods have been developed to separate no-carrier-added ¹¹¹Ag from proton irradiated thorium targets and associated fission products as an ancillary process to an existing ²²⁵Ac separation design. Herein we report the separation of ¹¹¹Ag both prior and subsequent to ²²⁵Ac recovery using CL resin, a solvent impregnated resin (SIR) that carries an organic solution of alkyl phosphine sulfides (R₃P = S) and alkyl phosphine oxides (R₃P = O). The recovery yield of ¹¹¹Ag was 93 ± 9% with a radiochemical purity of 99.9% (prior) and 87 ± 9% with a radiochemical purity of 99.9% (subsequent to) ²²⁵Ac recovery. Both processes were successfully performed with insignificant impacts on ²²⁵Ac yields or quality. Measured equilibrium distribution coefficients for silver and ruthenium (a residual contaminant) on CL resin in hydrochloric and nitric acid media are reported, to the best of our knowledge, for the first time. Additionally, measured cross sections for the production of ¹¹¹Ag and ^110mAg for the ²³²Th(p,f)^110m,111Ag reactions are reported within.

[en] Highlights: • Protactinium-230 produced from proton irradiation of thin thorium targets at LANL-IPF. • Proton energy distribution through the targets determined from nickel monitor foil reactions and SRIM simulations. • Solid-phase extraction chromatography of ²³⁰Pa from the irradiated target matrix with high recovery. • Production yields of ²³⁰Pa exceeding the theoretical yields. - Abstract: Uranium-230 (t_1/2 = 20.8 d) is an alpha-emitting radionuclide that has potential application in targeted alpha therapy (TAT) of cancer. Its parent isotope ²³⁰Pa (t_1/2 = 17.4 d), can be produced by proton irradiation of thorium metal targets. Preliminary ²³⁰Pa production runs were performed at the Los Alamos National Laboratory Isotope Production Facility (LANL-IPF) using thin thorium metal targets and a proton beam energy of 15–30 MeV, followed by radiochemical separation of ²³⁰Pa from the irradiated target matrix. The measured ²³⁰Pa production yields were found to exceed the predicted values in most of the experiments that were performed. This data will inform further production efforts for providing ²³⁰Pa/²³⁰U for clinical trials.