The main purpose of this study was to implement EBT3 dosimetry in the proton low-energy radiobiology line of the TOP-IMPLART accelerator, having a maximum energy of 7 MeV. Low-energy proton and (60)Co calibrated sources were used to investigate the behavior of film response vs to be written in italicum dose. The calibration in 5 MeV protons is currently used for dose assessment in the radiobiological experiments at the TOP-IMPLART accelerator carried out at that energy value.

Recently, a compact solid-state neutron detector capable of simultaneously detecting thermal and fast neutrons was proposed [M. Marinelli et al., Appl. Phys. Lett. 89, 143509 (2006)]. Its design is based on a p-type/intrinsic/metal layered structure obtained by Microwave Plasma Chemical Vapor Deposition (CVD) of homoepitaxial diamond followed by thermal evaporation of an Al contact and a ⁶LiF converting layer. Fast neutrons are directly detected in the CVD diamond bulk, since they have enough energy to produce the ¹²C(n, α)⁹Be reaction in diamond. Thermal neutrons are instead converted into charged particles in the ⁶LiF layer through the ⁶Li(n, α)T nuclear reaction. These charged particles are then detected in the diamond layer. The thickness of the ⁶LiF converting layer and the CVD diamond sensing layer affect the counting efficiency and energy resolution of the detector both for low- (thermal) and high-energy neutrons. An analysis is carried out on the dynamics of the ⁶Li(n, α)T and the ¹²C(n, α)⁹Be reactions products, and the distribution of the energy released inside the sensitive layer is calculated. The detector counting efficiency and energy resolution were accordingly derived as a function of the thickness of the ⁶LiF and CVD diamond layers, both for thermal and fast neutrons, thus allowing us to choose the optimum detector design for any particular application. Comparison with experimental results is also reported

With the purpose of studying the behavior of novel solid-state lithium fluoride (LiF) films detectors based on the photoluminescence (PL) of radiation-induced defects for proton beam diagnostics and dosimetry, polycrystalline LiF thin films thermally evaporated on glass were irradiated at room temperature in a linear proton accelerator under development at ENEA. The irradiations were performed in air by proton beams of 3 and 7 MeV energy, in a fluence range from 10 11 to 10 15 protons/cm 2 . In the LiF films, proton irradiation induces the formation of F2 and F + 3 aggregate color centers, which simultaneously emit broad PL bands in the visible spectral range under excitation in the blue one. The integrated PL signal, acquired by a fluorescence microscope equipped with a s-CMOS camera, shows a linear dependence on the dose deposited in LiF films, extending from 10 3 to 10 6 Gy, independently of the proton energy. A simple theoretical model is put forward for the formation of color centers in LiF and is utilized to obtain a proton beam dose-map by processing the PL image stored in the LiF film detectors.

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