Quantitative, non-destructive elemental composition analysis of 3D-structured samples

Prompt-gamma activation analysis (PGAA) is a non-destructive nuclear analytical method to determine the bulk elemental composition of samples with very good metrological quality. We have developed an experimental procedure to collect position-sensitive PGAA spectra, and a generally-applicable matrix-effect correction method based on Monte Carlo simulations. This latter eliminates the bias between measurement points of a pencil-beam raster scan, caused by the geometry-dependent neutron self-shielding and gamma-ray self-absorption effects. The procedure has been validated here to perform non-invasive, spatially-resolved, non-destructive bulk analysis of voluminous, inhomogeneous, and/or spatially structured samples. By combining the non-destructive position-sensitive prompt-gamma activation analysis, neutron computed tomography, and Monte Carlo computer simulations, quantitative matrix-effect correction of a structured, multi-component sample has been achieved.