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Gallium nitride commercial transistors (GaN FET) are great candidates as power devices tolerant to the effects of Total ionizing dose (TID). Therefore, we have evaluated its robustness by analysing parameters in its characteristic parameters. Devices were exposed to a 10 keV X-ray source accumulating a total of 350 krad(Si). However, results indicate that the tested components are more tolerant to the effects of TID when in on-state mode rather than the off-mode, that is, when the device is working, which is good news for COTS applications in environments subject to the effects of ionizing radiation.

The half life of the 7− isomeric state of the odd-odd 68Ga nucleus was measured using a particle-γ delayed coincidence technique. The 68Ga nuclei were produced using the fusion-evaporation reaction 55Mn(16O,2pn)68Ga at 55 MeV incident beam energy. The beam was produced by the 8 MV Pelletron accelerator of the Nuclear Physics Open Laboratory of the University of São Paulo. The half life was measured using the Isomeric State Measurement System (SISMEI). The obtained value was 60.83(25) ns, compatible with previous measurements. The 68Ga excited states were well described with the Large Scale Shell Model using the JUN45 residual interaction.

This work is part of the NUMEN Project (NUclear Matrix Elements for Neutrinoless double beta decay), which, among other goals, aims to measure cross-section of double charge exchange reactions (DCE). In the experiments to be carried out at the Laboratori Nazionali del Sud, in Catania, Italy, a target deposited on a carefully chosen backing (substrate) will be irradiated with a high energy ion beam and, importantly, neither the target nor the substrate will be allowed to overheat as this would affect their structures and its properties, which are special for the experiment. Within this context, highly oriented pyrolytic graphite (HOPG) was chosen as a substrate for the deposition of target elements that will be irradiated by ions such as 12C, 18O and 20Ne, with energies ranging from 15 MeV/u to 60 MeV/u. HOPG is considered a semimetal structured in layers, being composed of a stack of graphene sheets with a small and very subtle disorientation (less than 1°), which makes it to approach to a single crystal. With its specific flat hexagonal molecular structure, consisting only of carbon atoms, HOPG has good thermal conductivity in these sheets, making it an excellent candidate as a heat sink. However, for the HOPG to act with thermal energy dissipation functionality during the experiments proposed by the NUMEN project, it is necessary to verify whether possible changes caused by exposure to the radiation beam have a direct or indirect influence on its mechanical and thermal properties. Regarding the thermal conductivity, vacancies produced during irradiation is one of the factors that considerably decrease such property. As the production of vacancies during irradiation is one of the factors that considerably decrease thermal conductivity, in this work it was used the SRIM/TRIM code simulations to investigate the mechanisms of vacancy production in the target plus HOPG backing system. In the simulations, it was considered different types and doses of incident ion beams as well as different target thickness. From the results it was possible to estimated how long a target-HOPG system can be irradiated before the HOPG high heat conductivity property is lost.

The study proposed in this paper aims to analyze macro and micronutrients in coffee powder samples from Brazil, Venezuela and Colombia, in two different stages of coffee preparation: before and after coffee filtering. In the analyzed samples, presence of K, Rb, Ca, Cl, S, Sr and Fe elements in coffee powder and coffee grounds using Energy Dispersive X-ray fluorescence (ED-XRF) was quantified. The presence of 40K and the radionuclides from the uranium and thorium series decays were verified using gamma-ray spectrometry analyses. With the results obtained using these two techniques, it was possible to estimate the ingestion index for natural radioisotopes. The results show that the annual dose due to coffee ingestion reaches 1.96(4) mSv, depending on the origin of the coffee and considering the annual coffee consumption in Brazil. Elemental Composition analysis of coffee grounds indicates that it can be reused as a product with a high concentration of nutrients.

Mean lifetimes have been measured for superdeformed bands of 145Gd with the Doppler-shift attenuation method. The extracted quadrupole moments of the yrast and first excited superdeformed bands are Q 0 =11.8±0.8 e b and Q 0 =13.2±1.0 e b, respectively. The configuration assignments based on the quadrupole moments are π61π[404]9/2ν[514]9/2ν70 for the yrast superdeformed band and π62ν[642]5/2ν70 for the first excited superdeformed band between the two known crossings.

The decay out of the yrast and excited highly deformed (HD) bands in ${}^{134}$Nd has been investigated via the ${}^{28}\mathrm{Si}{+}^{110}\mathrm{Pd}$ reaction at 130 MeV using the GASP array. Several deexcitation pathways have been established for both the yrast and excited HD bands. The resulting spins remove previous ambiguities in the assignment of the excited HD band and confirm the structure assigned to the yrast HD band. The decay out is understood in terms of mixing between the normal-deformed and HD states, which is triggered by the crossing between the $\ensuremath{\nu}{i}_{13/2}$ and $\ensuremath{\nu}{d}_{5/2}$ orbitals.

A g-factor measurement in the superdeformed band of 133Nd has been performed by applying the transient field method in coincidence mode with the multidetector array GASP. The 133Nd nuclei were populated by the 104Pd(32S,2pn) reaction at a bombarding energy of 135 MeV. Polarized Gd has been used as ferromagnetic host. A mean g-factor of g = 0.31(8) has been determined at the I π = 41 2 + superdeformed state. The experimental value is compared with theoretical predictions and supports the assignment of the superdeformed band to the ν[660] 1 2 + Nilsson intruder orbital.

The use of double charge exchange reactions is discussed in view of their application to extract information that may be helpful to determinate the nuclear matrix elements entering in the expression of neutrinoless double beta decay half-life. The strategy adopted in the experimental campaigns performed at INFN - Laboratori Nazionali del Sud and in the analysis methods within the NUMEN project is briefly described, emphasizing the advantages of the multi-channel approach to nuclear reaction data analysis. An overview on the research and development activities on the MAGNEX magnetic spectrometer is also given, with a focus on the chosen technological solutions for the focal plane detector which will guarantee the performances at high-rate conditions.