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Ion beam analysis of fluorine has applications in research on teeth and bones, materials science, geochemistry and archaeometry. A novel PIGE (Particle Induced Gamma-ray Emission) standard free methodology for fluorine content determination for in-depth heterogeneous samples based on the excitation function of the 19F(p,p’γ)19F nuclear reaction is presented. New precise cross section measurements of this reaction in the proton energy range 2.1 to 4.1 MeV have been performed. In addition, the ERYA-Profiling code, a computer program specially developed for PIGE analysis of in-depth heterogeneous samples, employed this new excitation function in a case study where different fluorine simulated depth profiles probed the capability of insight into fluorine distributions in a given sample, showing the potential of PIGE analysis.

In this work, the cross section of the reactions 7Li(p,pγ)7Li (γ – 478 keV) at the proton energy range 2.0–4.2 MeV was measured. The measurements were carried out at the 3 MV Tandem Accelerator at the CTN/IST Laboratory in Lisbon. To validate the obtained results, calculated gamma-ray yields were compared, at several proton energy values, with experimental yields for thick samples made of inorganic compounds containing lithium. In order to quantify the light elements present in the samples, we used a standard free method for PIGE in thick samples, based on a code – Emitted Radiation Yield Analysis (ERYA), which integrates the nuclear reaction excitation function along the depth of the sample. We also demonstrated the capacity of the technique for analysis of Li ores, as Spodumene, Lithium Muscovite and Holmquistite, and Li-alloys for plasma facing materials showing that this is a reliable and accurate method for PIGE analysis of Li in thick samples.

In recent decades, the processes of fusion of 16 O were studied both theoretically and experimentally. However, the theoretical calculations are unable to fit both elastic scattering cross sections and fusion S-factors. The use of 16 O thin transmission targets is required to measure the elastic forward scattering 16 O + 16 O reaction. The areal density of the target must be high to maximize the reaction products yields, but not so high as to allow a correct calculation of the effective beam energy. Besides this, the target must withstand beam interactions without noticeable deterioration, and contaminants must be minimal. In this study, the production of thin targets is performed with an innovative technique. Beam characterization and preliminary spectrum for the elastic scattering are also presented, showing the suitability of these targets for the proposed reaction.

36Cl is one of several short to medium lived isotopes (as compared to the earth age) whose abundances at the earlier solar system may help to clarify its formation process. There are two generally accepted possible models for the production of this radionuclide: it originated from the ejecta of a nearby supernova (where 36Cl was most probably produced in the s-process by neutron irradiation of 35Cl) and/or it was produced by in-situ irradiation of nebular dust by energetic particles (mostly, p, a, 3He -X-wind irradiation model).The objective of the present work is to measure the cross section of the 37Cl(p,d)36Cl and 35Cl(d,p)36Cl nuclear reactions, by measuring the 36Cl content of AgCl samples (previously bombarded with high energy protons and deuterons) with AMS, taking advantage of the very low detection limits of this technique for chlorine measurements.For that, the micro-AMS system of the LF1/ITN laboratory had to be optimized for chlorine measurements, as to our knowledge this type of measurements had never been performed in such a system (AMS with micro-beam).Here are presented the first results of these developments, namely the tests in terms of precision and reproducibility that were done by comparing AgCl blanks irradiated at the Portuguese National Reactor with standards produced by the dilution of the NIST SRM 4943 standard material.