An innovative electrostatic particle accelerator was developed by INFN and Padova University. The high voltage generation scheme is based on a recent technique which generates it through series connection of lower voltage stages made of independently stabilized generators, each one providing a remotely settable voltage, actively controlled at about 2.0 & times; 10-4 V/V stability. All the power needed for the operation is supplied to each stage by laser light fed to high efficiency photovoltaic cells through optical fibres. The all-optical feeding scheme decouples each stage from other stages and ground reference. The maximum attainable voltage is thus limited only by the insulation of the last stage with respect to the mechanical structure of the container. We tested electrical insulation provided both by a dielectric liquid and high-pressure gases, choosing the former one eventually. The accelerator, produced in a tandem scheme, with a stripping carousel for continuous operation, was fully engineered, assembled and tested for high voltage, yet without ion beam. The concept, the design, the realization and the experimental results will be discussed.
161Tb is a promising radionuclide for targeted beta therapy due to its favorable half-life, (3- emission, and coemission of Auger/conversion electrons. In this study, its production was systematically investigated via three neutron irradiation pathways: direct 159Tb irradiation, indirect irradiation of natural gadolinium, and enriched 160Gd targets. An integrated computational framework combining MATLAB-based analytical modeling using Bateman chain equations and MCNPX 2.6.0 Monte Carlo simulations was applied to predict time-dependent activity evolution, assess impurity formation, and evaluate radionuclidic purity under identical irradiation conditions. The analytical model accurately reproduced the overall trends of 161Tb and co-produced isotopes, while MCNPX provided detailed insights into neutron transport, spectral effects, and self-shielding. Among the routes, enriched 160Gd yielded the highest 161Tb activity with minimal long-lived impurities, natural gadolinium provided a balanced compromise between yield and purity, and direct 159Tb irradiation was limited by significant 160Tb co-production. This combined approach offers a robust, predictive, and efficient platform for optimizing 161Tb production, guiding experimental design, and supporting the development of high-purity therapeutic radiopharmaceuticals.
A TE211-mode Single Hybrid Cavity linear accelerator (TE211-mode SHC linac) is an ion linac with a 4-vane RFQ and a double IH-DTL in a single cavity. A double IH-DTL incorporates drift-tubes inside from alternating horizontal and vertical directions, excites the TE211-mode and provides gap voltage. A TE211-mode SHC linac excites the TE211-mode to accelerate ion beams in the low energy region (several tens of keV to about 3 MeV) with high efficiency. In this study, a TE211-mode SHC linac proof-of-principle machine was designed and its acceleration properties were evaluated using a beam simulation code. Specifically, the cell parameters of the RFQ electrode and the drift tube were designed. Furthermore, end-to-end beam simulations in the TE211-mode SHC linac were performed to evaluate beam acceleration characteristics.
Museum herbaria are collections of preserved, dried plants, bearing an exceptional value as archives of botanical history and biodiversity, an invaluable resource for modern research in several fields. The Museum of Natural History of the University of Florence (Italy) houses the Florentine Botanical Collections (FI), which include some of the most ancient and largest herbaria in the world, such as the Herbarium Centrale Italicum (FI-HCI). Like many herbaria worldwide, these collections are affected by Hg contamination resulting from the historical use of corrosive sublimate (HgCl2) as a pesticide for specimen preservation. Although this practice was discontinued over a century ago, elemental Hg degassing from the samples and residual Hg compounds on them prevent the full accessibility and valorisation of these collections. This work aims at characterizing the concentrations and in-depth distributions of Hg and other possibly related elements (Cl, and S) within contaminated samples from the Florentine collections using external beam ion beam analysis (IBA) techniques. Nine representative specimens-eight from the 19th century and a recent, untreated one (blank)-were selected for PIXE and EBS measurements, with a 3 MeV proton beam, at the INFN LABEC 3 MV Tandem accelerator. The study revealed that contamination variably affects both the plant matrix and the support paper: Hg concentrations measured on dark stains on paper, which were identified as superficial accumulations of Hg, were significantly higher than those measured on clear paper and on the plant matrix, where Hg penetrates deeply instead. It was also possible to make some hypotheses about the speciation of Hg in the samples.
Tungsten-doped high-density carbon (HDC) target pellets have emerged as promising ablator materials for inertial confinement fusion (ICF) applications. However, ensuring a uniform distribution of dopants and accurately quantifying their concentration remains a challenge. In this study, we present a non-destructive approach for three-dimensional (3D) characterization of tungsten dopants within HDC pellets using Rutherford Backscattering Spectrometry Tomography (RBS-T). A scanning nuclear microprobe system was employed to simultaneously collect RBS and Particle-Induced X-ray Emission (PIXE) data. PIXE analysis revealed an average tungsten concentration of approximately 0.31 atomic percent with uniformity across the pellet. Depth-resolved RBS measurements, conducted with a 5-MeV C3+ ion beam, were segmented into multiple layers with an approximate thickness of 100 nm each. Two-dimensional distribution maps of tungsten at various depths were obtained and subsequently integrated to construct a 3D spatial distribution model. The results demonstrate that RBS-T enables 3D mapping and concentration measurement of the tungsten dopants within HDC pellets, effectively overcoming the limitations inherent in PIXE-based tomography for completely penetrating samples and providing enhanced depth resolution without spectral interference from the carbon matrix. This method offers a robust and alternative means for visualizing dopant homogeneity in ICF target materials.
