The candidate will conduct research experiments for accurate radiofluoresence dating. The duties will involve feldspar specimens with a uniform surface, i.e. polished thin slices. Higher resolution X-ray fluorescence (XRF) maps will be generated and the elemental composition of each grain, independent of surface inhomogeneity, will be identified and quantified. A correlation between the XRF and luminescence maps will then provide a better understanding of the link between the IR-RF signal and chemical composition. A similar correlation with XANES spectroscopy maps will reveal the oxidation states of defects in the grains, which are interacting with light and ionizing radiation. In the second step, the advanced level, IR-RF will be collected at the same time as recording XRF maps on a new set of fresh slices. XANES spectra/maps and IR-RF emission/spectra will also be recorded at the same time. Such measurements will necessitate the integration of an EM-CCD/PMT detector and bandpass filters into the already existing beamline setup; integration will be carried out under the guidance of the beamline staff. Such measurements are crucial to relate chemical elements and their oxidation state with the IR-RF signals recorded at the same site and, therefore, to identify the cause of the IR-RF signal sensitivity/shape in feldspars of different geological origin.
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