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A novel active focusing system was developed for enhancing the irradiation performance of the 18 MeV medical cyclotron in operation at the Bern University Hospital in view of the production of non-conventional medical radioisotopes using solid targets. In several cases, such as the production of 43 Sc and 44 Sc, the beam has to be kept stable within a very small target of about 5 mm diameter. For this purpose, we conceived and realized an apparatus based on a compact focusing and steering magnet system followed by a two-dimensional beam monitoring detector and a specific feedback software that drives the magnet to optimize the beam for a given irradiation set-up. We report on the design, realization and validation beam tests performed using the research beam transfer line of the Bern cyclotron. We demonstrated that the beam spot can be kept on target thanks to the fact that the system automatically reacts to perturbations. Compactness is one of the key features of this system, allowing its use in accelerator facilities with limited space, such as medical cyclotrons for radioisotope production. [ABSTRACT FROM AUTHOR]

Additive manufacturing/3D printing is a rapidly maturing field with potential advantages for the fabrication of chemical processing equipment. A demonstration of the molybdenum solvent-extraction process, developed to recover Mo for the production of 99Mo/99mTc from enriched 98Mo or 100Mo, was accomplished using a nine-stage bank of additive-manufacturing-fabricated 2-cm annular centrifugal contactor-separator devices. The results from the demonstration are presented along with the benefits and shortcomings of the 3D printed contactors. This paper also discusses recent developments in the design of 3D printed contactors in order to improve reliability and mitigate the effects of chemical degradation of additive-manufacturing media. [ABSTRACT FROM AUTHOR]

A novel active focusing system was developed for enhancing the irradiation performance of the 18 MeV medical cyclotron in operation at the Bern University Hospital in view of the production of non-conventional medical radioisotopes using solid targets. In several cases, such as the production of 43Sc and 44Sc, the beam has to be kept stable within a very small target of about 5 mm diameter. For this purpose, we conceived and realized an apparatus based on a compact focusing and steering magnet system followed by a two-dimensional beam monitoring detector and a specific feedback software that drives the magnet to optimize the beam for a given irradiation set-up. We report on the design, realization and validation beam tests performed using the research beam transfer line of the Bern cyclotron. We demonstrated that the beam spot can be kept on target thanks to the fact that the system automatically reacts to perturbations. Compactness is one of the key features of this system, allowing its use in accelerator facilities with limited space, such as medical cyclotrons for radioisotope production.

Following the successful production of the radioimmunotheranostic nuclide 67Cu through the reaction of a 70Zn beam on a hydrogen gas target, our interest turned to the 99Mo/99mTc generator system. We produced 99Mo in inverse kinematics, with a100Mo beam at 12.0 MeV/nucleon impinging on a 4He gas target. The gas target was kept at liquid nitrogen temperature and pressures of 0.134(3), 0.280(6) and 1.33(3) atm. The produced isotopes and the beam were collected on a thick Al catcher foil. The 99Mo radioisotope can be produced in a one nucleon transfer occurring in peripheral reactions. Two competing factors determine the yield in such reactions, one is the cross-section which favors high mass targets, the other is the effective range which favors low-mass targets. Thus, at low 4He densities, higher beam energy at the exit of the gas target, most of the 99Mo production is generated in the Al foil, while at higher densities, most is generated in the gas target. The activity obtained at the end of the bombardment (given in Becquerel per particle nano-Amps per hour of irradiation), including the 4He gas and Al catcher contribution, were determined as 4.8(14), 2.5(7) and 3.8(11) kBq/(pnAh) for ρ gas = 0.83, 0.18 and 0.09 mg/cm3, respectively. These results are competitive to other accelerator production methods; however, the method reported has the additional advantages of needing significantly less amount of expensive enriched isotope and offers an easier and cleaner collection/separation method. • A novel approach to medical radioisotope production using inverse kinematics. • Radioisotope production using Cyclotron accelerators. • 99Mo/99mTc generator system. • 100Mo beam at 12.0 MeV/nucleon impinging on a 4He gas target. • Off-line γ-spectroscopy analysis and End of Bombardment Activities. [ABSTRACT FROM AUTHOR]

The production of 97Ru, a potential Single Photon Emission Computed Tomography (SPECT) radioisotope, was studied at ARRONAX. The cross-section of natMo(α,x)97Ru reaction was investigated in the range of 40⁻67 MeV irradiating the natMo and Al stacked-foils. The activities of 97Ru and other radioactive contaminants were measured via gamma spectroscopy technique. A global good agreement is observed between obtained cross-section results, previously reported values and TENDL-2017 predictions. Additionally, Radionuclide Yield Calculator, a software that we made available for free, dedicated to quickly calculate yields and plan the irradiation for any radioisotope production, was introduced. The yield of investigated nuclear reactions indicated the feasibility of 97Ru production for medical applications with the use of α beam and Mo targets opening the way to a theranostic approach with 97Ru and 103Ru.