High energy X-ray microscopy for characterisation of fuel particles

Abstract For the first time different high energy microanalysis techniques were combined to characterise individual micrometer sized radioactive particles. It was shown that particle characteristics including weathering rates and mobilisation of associated radionuclides are source specific and release-scenario dependent. Fuel particles released during the explosion are characterised by UO 2 -cores with surrounding layer of reduced U with low weathering rates. In contrast, fuel particles released during the subsequent fire show UO 2 -core with surrounding layers of oxidised U 2 O 5 /U 3 O 8 with high weathering rates