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Thin targets of isotopically enriched 48Ti metallic powder on Al foil substrates for the nuclear cross-section measurements were manufactured using the HIgh energy VIbrational Powders Plating method in vacuum. The target areal thickness of 0.2–2 mg/cm2 was achieved as measured by weighing as well as by Elastic Backscattering Spectroscopy (EBS) analysis. The quality of the targets, in particular the deposit uniformity, was evaluated by Scanning Electron Microscope (SEM) assisted by the Energy Dispersive Spectroscopy (EDS). The microstructure of the HIVIPP deposited targets was analyzed for the first time. SEM analysis showed that the coating microstructure was strongly related to the original powder microstructure. It was also observed that the coating was not a powder monolayer. The smaller powder particles, which were the first to move in the electric field, remained attached to the substrate and created the first layers of the deposit. Further layers of bigger particles were then attached to the first layer. The information about the deposit microstructure was utilized to model the EBS analysis results. The subset of the prepared 48Ti enriched targets was successfully used for the nuclear cross-section measurement campaign up to 40 MeV using the proton beam (115 nA) available at the C70 cyclotron in ARRONAX (Nantes, France).

In this paper we present maps of K, eU, and eTh abundances of Elba Island (Italy) obtained with a multivariate spatial interpolation of airborne {\gamma}-ray data using the constraints of the geologic map. The radiometric measurements were performed by a module of four NaI(Tl) crystals of 16 L mounted on an autogyro. We applied the collocated cokriging (CCoK) as a multivariate estimation method for interpolating the primary under-sampled airborne {\gamma}-ray data considering the well-sampled geological information as ancillary variables. A random number has been assigned to each of 73 geological formations identified in the geological map at scale 1:10,000. The non-dependency of the estimated results from the random numbering process has been tested for three distinct models. The experimental cross-semivariograms constructed for radioelement-geology couples show well-defined co-variability structures for both direct and crossed variograms. The high statistical correlations among K, eU, and eTh measurements are confirmed also by the same maximum distance of spatial autocorrelation. Combining the smoothing effects of probabilistic interpolator and the abrupt discontinuities of the geological map, the results show a distinct correlation between the geological formation and radioactivity content. The contour of Mt. Capanne pluton can be distinguished by high K, eU and eTh abundances, while different degrees of radioactivity content identify the tectonic units. A clear anomaly of high K content in the Mt. Calamita promontory confirms the presence of felsic dykes and hydrothermal veins not reported in our geological map. Although we assign a unique number to each geological formation, the method shows that the internal variability of the radiometric data is not biased by the multivariate interpolation., Comment: 43 pages, 9 figures, 5 tables. In Remote Sensing of Environment (2013)

An increasing demand of environmental radioactivity monitoring comes both from the scientific community and from the society. This requires accurate, reliable and fast response preferably from portable radiation detectors. Thanks to recent improvements in the technology, $\gamma$-spectroscopy with sodium iodide scintillators has been proved to be an excellent tool for in-situ measurements for the identification and quantitative determination of $\gamma$-ray emitting radioisotopes, reducing time and costs. Both for geological and civil purposes not only $^{40}$K, $^{238}$U, and $^{232}$Th have to be measured, but there is also a growing interest to determine the abundances of anthropic elements, like $^{137}$Cs and $^{131}$I, which are used to monitor the effect of nuclear accidents or other human activities. The Full Spectrum Analysis (FSA) approach has been chosen to analyze the $\gamma$-spectra. The Non Negative Least Square (NNLS) and the energy calibration adjustment have been implemented in this method for the first time in order to correct the intrinsic problem related with the $\chi ^2$ minimization which could lead to artifacts and non physical results in the analysis. A new calibration procedure has been developed for the FSA method by using in situ $\gamma$-spectra instead of calibration pad spectra. Finally, the new method has been validated by acquiring $\gamma$-spectra with a 10.16 cm x 10.16 cm sodium iodide detector in 80 different sites in the Ombrone basin, in Tuscany. The results from the FSA method have been compared with the laboratory measurements by using HPGe detectors on soil samples collected in the different sites, showing a satisfactory agreement between them. In particular, the $^{137}$Cs isotopes has been implemented in the analysis since it has been found not negligible during the in-situ measurements., Comment: accepted by Science of Total Environment: 8 pages, 10 figures, 3 tables

The production of innovative radionuclides in the context of theranostics is currently a topic of great interest. Various INFN projects are underway in search of new data and new techniques for radionuclides production. Among the possible channels under study, recent developments indicate 67Cu and 47Sc as good candidates competitive with more traditional nuclides, thanks to their application both for diagnostic and for therapy. INFN recently started two projects for the measurement of proton-induced reactions, considering the forthcoming use of the high-performance cyclotron installed at INFN-LNL (70 MeV maximum energy): COME in CSN3 (2016) and PASTA in CSN5 (Young Researchers grants 2016). The knowledge of reaction cross sections at low-intermediate energies is crucial in this context and, in parallel to the need of new measurements, it is important also to review the current situation in the reaction-model simulation of the production yields, by using the existing and available nuclear reaction codes. In particular the FLUKA code, based on the PEANUT (Pre-Equilibrium Approach to Nuclear Thermalisation) model, was used to calculate the production of residual nuclei in different experiments and is already validated with data. In this study we use FLUKA to calculate the reaction cross sections for the production of copper and scandium isotopes at the energy of interest for the LARAMED project (10–100 MeV). A comparison of the results obtained with dedicated codes (Talys and Empire) and with available experimental data is also given.