Comparative Study of Raman and EPMA Elemental Mapping of an Unirradiated MOX Sample

The distribution of U and Pu of a mixed-oxide fuel sample is analyzed by Raman spectroscopy and electron probe microanalysis, with the goal of comparing the distribution maps from the two techniques. Qualitatively, the maps reveal the same features of Pu-rich agglomerates and the near Pu-free UO₂ matrix, and the differences between the derived absolute concentrations are within 10%. Differences are likely due to a shift in the Raman signal originating from the local stoichiometry variation or self-irradiation damage.