Gaia Pupillo

An α-drift tube linac (DTL) is a high-performance linac conceived for radioisotope production. The use of alpha particle beams may make yielding radionuclides hard to obtain with traditional nuclear reactors or by proton accelerators, by exploiting new reaction routes. This approach may lead to better radionuclide impurity profiles, simplifying the radiochemical separation and purification process. The key idea of the α-DTL is to use a high duty cycle linac composed of an electron cyclotron resonance ion source, a radio frequency quadrupole, and a DTL, able to accelerate an average current of 0.5 mA alpha beam from few MeV to 40 MeV, to cover the cross sections of many interesting reactions for radionuclides. The innovative feature of this linac is the capability of regulating energy at the exit of the DTL, by a particular use of the stabilization system (post couplers) of the DTL cavity.

The availability of the theranostic radionuclide 47Sc is hindered by the lack of a reliable high purity production method. The aim of this work is to evaluate a less considered pathway exploiting deuteron beams on enriched 49Ti targets. The investigation started from the measurements of the production cross sections of the emergent radionuclide 47Sc, as well as of the co-produced contaminants which play an important role on the final purity and in the evaluation of the dose eventually administered to a patient. Enriched 49Ti targets, manufactured at the INFN-LNL (National Institute of Nuclear Physics-Legnaro National Laboratories), were activated in several irradiation runs carried out at the GIP ARRONAX (Group of Public Interest Accelerator for Research in Radiochemistry and Oncology in Nantes-Atlantique) facility cyclotron utilizing the tunable 15÷35 MeV deuteron beam. The obtained cross section trends, which constitute the first measurement for some radionuclides, are compared to theoretical curves and literature data, when available. The experimental cross sections are then discussed to assess 49Ti(d,x) as a possible production route for 47Sc. The results demonstrated that 49Ti(d,α)47Sc can be considered as a valid alternative production route for the supply of this medically interesting radionuclide.

Future innovative radionuclides for cancer treatment at INFN: The Italian Institute for Nuclear Physics conducts cutting-edge research in the field of nuclear, particle, and astroparticle physics, as well as in developing technologies for research and their applications to benefit society. Founded in 1951, the Italian Institute for Nuclear Physics (INFN) is the public research institute that has taken up the scientific legacy of Enrico Fermi for more than seventy years. Among the four INFN National Laboratories, the Legnaro National Laboratories (LNL, Legnaro, Padova) are internationally recognised for conducting state-of-the-art research in the field of nuclear physics and its applications, thanks to the five particle accelerators and related technologies available there.

⁴⁷Sc is a theranostic radionuclide under the spotlight of the scientific community thanks to its potential for SPECT imaging and therapeutic applications. This work presents the recent measurements of proton-induced nuclear reaction cross-sections aimed at ⁴⁷Sc production using enriched ⁴⁸Ti, ⁴⁹Ti and ⁵⁰Ti targets from 23 up to 70 MeV. Since the co-production of contaminant isotopes is a key issue, and ⁴⁶Sc is the main one having a longer half-life than ⁴⁷Sc, the ^48/49/50Ti(p,x)⁴⁷Sc and ⁴⁶Sc cross sections are presented and compared with the scarce literature data and TALYS estimations.

The cross-sections of the ⁴⁸Ti(p,x)⁴⁷Sc, ^46cSc, ^44mSc, ^44gSc, ⁴³Sc, and ⁴⁸V nuclear reactions were measured from 18 to 70 MeV, with particular attention to ⁴⁷Sc production. Enriched ⁴⁸Ti powder was deposited on an aluminum backing and the obtained targets were characterized via elastic backscattering spectroscopy at the INFN-LNL. Targets were exposed to low-intensity proton irradiation using the stacked-foils technique at the ARRONAX facility. Activated samples were measured using γ-spectrometry; the results were compared with the data int he literature and the theoretical TALYS-based values. A regular trend in the new values obtained from the different irradiation runs was noted, as well as a good agreement with the literature data, for all the radionuclides of interest: ⁴⁷Sc, ^46cSc, ^44mSc, ^44gSc, ⁴³Sc, and ⁴⁸V. ⁴⁷Sc production was also discussed, considering yield and radionuclidic purity, for different ⁴⁷Sc production scenarios.