Speaker
Description
The ISOL (Isotope Separation On-Line) techniques [1], uses an ion source to produce a radioactive ion beam and further separate the unwanted by-products. The ion-sources dedicated to the production of Radioactive Ion Beams (RIB), necessary for the ISOL techniques, has to be highly efficient, selective (to reduce the isobar contamination) and fast (to limit the decay losses of short-lived isotopes). The release and ionization of desired isotopes is essential of ISOL techniques. Different target materials and ion-sources are used to achieve this goal. This has been investigated at Low Energy Radioactive Ion Beam (LERIB) facility, which is presently offline and under development at iThemba LABS, hot-cavity ion-source which employs the surface ionization techniques [2]-[3]. This ion source was used to optimize the ionization of potassium atoms, and mass separated potasium-40 isotopes. This ion source was used to achieve the surface ionization of terbium fluoride and gadolinium oxide producing various molecular ion beams such as terbium mono-fluoride (TbF+) and gadolinium mono-fluoride (GdF+), terbium di-fluoride (TbF2+) and gadolinium di-fluoride (GdF2+), gadolinium monoxide (GdO+) and terbium monoxide (TbO+). The hot cavity ion source produces little terbium and gadolinium ion beam. This experiment was on the investigation of the best target material for the production and extraction of Tb radionuclide from Gd target material.
The LERIB facility will eventually be purposed for the production of Terbium and Actinium isotopes, which are used in cancer theranostics [4]-[5]. The results presented contribute towards the ongoing research and development of the ion sources at LERIB, with the aim to eventually produce, separate, and implant clean beams of Tb and Ac isotopes on target, with the goal to later produce isotopic beams from the implantation targets.
[1] O. Kofoed-Hansen, K. Nielsen, Short-lived krypton isotopes and their daughter substances, Physical Review Journals 82 (96) (1951) 499. doi:10.1103/PhysRev.82.96.2.
[2] Yuan Liu, Yoko Kawai, and Hassina Z Bilheux. Characterization of a tubular hot-cavity surface ionization source. In Proceedings of the 2005 Particle Accelerator Conference. IEEE, 2005.
[3] R. Kirchner, E. Roeckl, Investigation of small-volume gaseous discharge ion sources for isotope separation on-line, Nuclear Instruments and Methods 131 (2) (1975) 371–374. doi:10.1016/0029-554X(75)90342-0.
[4] Müller, C. et al. Alpha-PET with terbium-149: Evidence and perspectives for radio-theranostics. EJNMMI Radiopharm. Chem. 1, 2–6 (2016).
[5] Kratochwil, C. et al. Targeted α-therapy of metastatic castration-resistant prostate cancer with 225Ac-PSMA-617: Swimmer-plot analysis suggests efficacy regarding duration of tumor control. J. Nucl. Med. 59, 795–802 (2018).
