Neutron tomography is a form of computed tomography involving the production of three-dimensional images by the detection of the absorbance of neutrons produced by a neutron source.[1] It creates a three-dimensional image of an object by combining multiple planar images with a known separation.[2] It has a resolution of down to 25 μm.[3][4] Whilst its resolution is lower than that of X-ray tomography, it can be useful for specimens containing low contrast between the matrix and object of interest; for instance, fossils with a high carbon content, such as plants or vertebrate remains.[5]
Neutron tomography can have the unfortunate side-effect of leaving imaged samples radioactive if they contain appreciable levels of certain elements such as cobalt,[5] however in practice this neutron activation is low and short-lived such that the method is considered non-destructive.
The increasing availability of neutron imaging instruments at research reactors and spallation sources via peer-reviewed user access programs[6] has seen neutron tomography achieve increasing impact across diverse applications including earth sciences, palaeontology, cultural heritage, materials research and engineering. In 2022, it was reported in the journal Gondwana Research that an ornithopod dinosaur was serendipitously discovered by neutron tomography in the gut content of Confractosuchus, a Cretaceous crocodyliform from the Winton Formation of central Queensland, Australia.[7] This is the first time that a dinosaur has been discovered using neutron tomography, and to this day, the partially digested dinosaur remains entirely embedded within the surrounding matrix.[8]
See also
edit- Winkler, B. (2006). "Applications of Neutron Radiography and Neutron Tomography". Reviews in Mineralogy and Geochemistry. 63 (1): 459–471. Bibcode:2006RvMG...63..459W. doi:10.2138/rmg.2006.63.17.
- Schwarz, D.; Vontobel, P. L.; Eberhard, H.; Meyer, C. A.; Bongartz, G. (2005). "Neutron tomography of internal structures of vertebrate remains: a comparison with X-ray computed tomography" (PDF). Palaeontologia Electronica. 8 (30).
- Mays, C.; Cantrill, D. J.; Stilwell. J. D.; Bevitt. J. J. (2017). "Neutron tomography of Austrosequoia novae-zeelandiae comb. nov. (Late Cretaceous, Chatham Islands, New Zealand): implications for Sequoioideae phylogeny and biogeography". Journal of Systematic Palaeontology. 16 (7): 551–570. doi:10.1080/14772019.2017.1314898. S2CID 133375313.
References
edit- ^ Grünauer, F.; Schillinger, B.; Steichele, E. (2004). "Optimization of the beam geometry for the cold neutron tomography facility at the new neutron source in Munich". Applied Radiation and Isotopes. 61 (4): 479–485. Bibcode:2004AppRI..61..479G. doi:10.1016/j.apradiso.2004.03.073. PMID 15246387.
- ^ McClellan Nuclear Radiation Center
- ^ "Neutron Tomography". Paul Scherrer Institut.
- ^ "Neutron Tomography NMI3". NMI3.
- ^ a b Sutton, M. D. (2008). "Tomographic techniques for the study of exceptionally preserved fossils". Proceedings of the Royal Society B: Biological Sciences. 275 (1643): 1587–1593. doi:10.1098/rspb.2008.0263. PMC 2394564. PMID 18426749.
- ^ "User facilities". www.isnr.de. Retrieved 2022-02-18.
- ^ White, Matt A.; Bell, Phil R.; Campione, Nicolás E.; Sansalone, Gabriele; Brougham, Tom; Bevitt, Joseph J.; Molnar, Ralph E.; Cook, Alex G.; Wroe, Stephen; Elliott, David A. (2022-02-10). "Abdominal contents reveal Cretaceous crocodyliforms ate dinosaurs". Gondwana Research. 106: 281–302. Bibcode:2022GondR.106..281W. doi:10.1016/j.gr.2022.01.016. ISSN 1342-937X. S2CID 246756546.
- ^ "Nuclear techniques confirm rare finding that crocodile devoured a baby dinosaur | ANSTO". www.ansto.gov.au. Retrieved 2022-02-18.