Beeldvorming: A non-invasive look inside statues

Neutron tomography on bronzes has proven its value in revealing intriguing features otherwise hidden in the inaccessible interior of statues[1,2], as shown in Figure 1. Neutron transmission has shown promise for quantitative analyses of bronze alloys using neutron techniques [3]. By combining neutron and gamma-ray tomography we aim to elevate the non-invasive method of neutron tomography to the next level by identifying the chemical composition of all structures in the interior, quantitatively. Neutron and gamma-ray tomography are highly penetrating techniques and are therefore the only non-invasive methods to achieve such quantitative information throughout the entire bulk of an art object. The quantification of the spatially resolved chemical composition is determined by data fusion of neutron and gamma-ray tomography, where the specific sensitivities of both techniques serve as mutual boundary conditions in the reconstruction of the 3D elemental model. The data generated by our research will deliver unprecedented insight in the ancient production process of these art objects and reveal in-depth information on possible past restorations. Such information is essential to (technical) art historians who study the material, cultural and religious context of these objects. Information on their chemical and physical stability will, in turn, enable conservators to develop a scientifically grounded strategy for the preservation of this precious cultural heritage. Besides delivering quantitative compositional information about the statues interior to scientists, the detailed graphical information of our reconstruction is an appealing and straightforward means to communicate the story behind the art object to the general public, a way to underline the societal impact of NICAS programmes.