Co-production of 155 Tb and 152 Tb irradiating 155 Gd / 151 Eu tandem target with a medium energy α-particle beam

• Published in: Nuclear medicine and biology Vol. 126-127; p. 108389
• Main Authors: Moiseeva, A N, Makoveeva, K A, Furkina, E B, Artyushova, E V, German, M N, Khomenko, I A, Konevega, A L, Kormazeva, E S, Novikov, V I, Aksenov, N V, Gustova, N S, Aliev, R A
• Format: Journal Article
• Language: English
• Published: United States 01.11.2023
• Subjects: Cyclotron; Cross section; Terbium-152; Nuclear reaction; Tandem target; Terbium-155
• ISSN: 1872-9614

Four terbium isotopes Tb emitting various types of radiation can be used for both diagnostics and therapy. Tb emits positrons and is ideal for PET. Tb is considered a promising Auger emitter and a diagnostic pair for other terbium therapeutic isotopes. Several methods for the production of Tb using charged particle accelerators have been proposed, but they all have significant limitations. The restricted availability of this isotope hinders its medical applications. We have proposed a new method for production of Tb, irradiating enriched Gd by alpha particles. The possibility of simultaneous production of two isotopes of terbium, Tb, was also studied for more efficient cyclotron beam use. Irradiation of Gd enriched targets and Gd /  Eu tandem target with alpha-particles with an energy of 54 MeV was carried out at the U-150 cyclotron at the NRC "Kurchatov Institute". The cross sections of nuclear reactions on Gd were measured by the stack foil technique, detecting the gamma-radiation of the activation products. The separation of rare earth elements was performed by extraction chromatography with the LN Resin. Tb was produced via Dy decay. The cross sections for the Tb and Dy production were measured by the irradiation of a gadolinium target enriched with the Gd isotope with alpha-particles in an energy range of 54 → 33 MeV. The yield of Dy on a thick target at 54 MeV was 130 MBq/μAh, which makes it possible to obtain 1 GBq of Tb in 11 hour-irradiation with 20 μA beam current. The possibility of simultaneous production of Tb by irradiation of Gd and Eu tandem target with medium-energy alpha-particles is implemented. Optimal irradiation energy ranges of alpha -particles as 54 → 42 MeV for Tb and 42 → 34 MeV for Tb were suggested. Product activity and radionuclidic purity were calculated.