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We investigate the quantum phases of hard-core dipolar bosons confined to a square lattice in a bilayer geometry. Using exact theoretical techniques, we discuss the many-body effects resulting from the pairing of particles across layers at finite density, including a novel pair supersolid, superfluid and solid phases. These results are of direct relevance to experiments with polar molecules and atoms with large magnetic dipole moments trapped in optical lattices.

47 Sc is one of the most promising theranostic radionuclides, thanks to its low energy γ-ray emission (159 keV), suitable for single photon emission computed tomography imaging and its intense β - emission, useful for tumour treatment. Despite promising preclinical results, the translation of 47 Sc-therapeutic agents to the clinic is hampered by its limited availability. Among different 47 Sc-production routes currently being investigated, the nat V(p,x) 47 Sc reaction has proved to be of particular interest, thanks to the low-cost and easy availability on the market of nat V material and the diffusion of medium energy proton cyclotrons. However, the cross section of this specific nuclear reaction is quite low and small amounts of Sc-contaminants are co-produced at energies E P ≤ 45 MeV, namely 48 Sc and 46 Sc. The main concern with these Sc-contaminants is their contribution to the patient absorbed dose. For such a reason, the absorbed dose contributions to healthy organs and the effective dose contributions by the three radioisotopes, 48 Sc, 47 Sc and 46 Sc, were evaluated using DOTA-folate conjugate (cm10) as an example of radiopharmaceutical product. Considering as acceptable the limits of 99% for the radionuclidic purity and 10% for the contribution of radioactive Sc-contaminants to the total effective dose after 47 Sc-cm10 injection, it was obtained that proton beam energies below 35 MeV must be used to produce 47 Sc through irradiation of a nat V target.

Evaluation of the radioisotopic purity of technetium-99m ( 99m Tc) produced in GBq amounts by proton bombardment of enriched molibdenum-100 ( 100 Mo) metallic targets at low proton energies (i.e. within 15-20 MeV) is conducted. This energy range was chosen since it is easily achievable by many conventional medical cyclotrons already available in the nuclear medicine departments of hospitals. The main motivation for such a study is in the framework of the research activities at the international level that have been conducted over the last few years to develop alternative production routes for the most widespread radioisotope used in medical imaging. The analysis of technetium isotopes and isomeric states ( 9x Tc) present in the pertechnetate saline Na 99m TcO 4 solutions, obtained after the extraction/purification procedure, reveals radionuclidic purity levels basically in compliance with the limits recently issued by European Pharmacopoeia 9.3 (2018 Sodium pertechnetate ( 99m Tc) injection 4801-3). Moreover, the impact of 9x Tc contaminant nuclides on the final image quality is thoroughly evaluated, analyzing the emitted high-energy gamma rays and their influence on the image quality. The spatial resolution of images from cyclotron-produced 99m Tc acquired with a mini-gamma camera was determined and compared with that obtained using technetium-99m solutions eluted from standard 99 Mo/ 99m Tc generators. The effect of the increased image background contribution due to Compton-scattered higher-energy gamma rays (E γ   >  200 keV), which could cause image-contrast deterioration, was also studied. It is concluded that, due to the high radionuclidic purity of cyclotron-produced 99m Tc using 100 Mo(p,2n) 99m Tc reaction at a proton beam energy in the range 15.7-19.4 MeV, the resulting image properties are well comparable with those from the generator-eluted 99m Tc.