The very first application of Fast Neutron Radiography in cultural heritage samples in South Africa under CRP F12024
South-Africa is extending its scientific capacities by applying Fast Neutron Radiography (FNR) and Fast Neutron Tomography (FNT) techniques for Cultural Heritage investigations for the very first time.
Within the CRP collaboration the South African Nuclear Energy Corporation (Necsa) has recently upgraded its fast neutron and dual energy gamma-ray source at the RFQ accelerator facility for radiography to determine both elemental and density profiles of materials used in energy sector. The 11B(d,n;γ)12C reaction for the production of an intense source of fast neutrons (1-10 MeV) and a dual gamma-ray source (4.43 and 15.11 MeV) were successfully combined.
This development coincides with a recent initiative from the South African National Research Foundation (NRF) to focus on fields of anthropology, palaeontology and cultural heritage, as the samples for these are highly abundant in South Africa. Compact accelerators are employed to produce an intense source of fast neutrons, which will be used in the examination of these samples via Fast Neutron Radiography (FNR) and Fast Neutron Tomography (FNT). Such applications are beyond the CRP work but were stimulated as an outcome of the F12024 CRP collaboration. The CRP has also strengthened the scientific capacities of Necsa.
Initial experiments were done at the radiofrequency quadrupole (RFQ) linac at Necsa, in which a radiograph of a skull was examined in-situ using a 7 MeV neutron beam. This is the very first application for FNR in cultural heritage samples in South Africa. The results show a radiograph (see Fig. 1) after the neutrons penetrated the sample and the frontal and maxillary sinus cavities are seen: the shapes of these are of high importance in the evolutionary studies of humans. This first successful work motivates the further upgrade and optimization of the imaging system for an increased resolution and image quality. The new design of the radiography system is being done in collaboration with Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany, represented by Mr Graham C. Daniels, a young scientist and the project Counterpart, who has received training with the support from the IAEA. The new system is expected to be installed by September 2015 and will be available to for both national and international users.
The initial work has already been presented at the World Conference on Neutron Radiography (WCNR-10) hosted by PSI in the town of Grindelwald from 5 to 10 October 2014, and resulted in a peer reviewed conference publication, "Fast neutron radiography at an RFQ accelerator system”, G.C Daniels, C.B Franklyn, V. Dangendorf, A. Buffler, B. Bromberger, accepted for publication in Physics Procedia (2015).
This success was achieved within the F12024 CRP with a main objective to stimulate research and development as well as practical applications of accelerator-based real-time and in-situ techniques, specifically in energy related scientific topics, and to grow further interdisciplinary and international collaborations.
16 research institutions are participating actively in this CRP from 16 Member States: Argentina, Australia, Canada, Croatia, Greece, India, Italy, Japan, Netherlands, Russian Federation, Serbia, Slovak Republic, Spain, South Africa, Ukraine, United States of America.