High energy tomography using cadmium zinc telluride detectors

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Accelerators, spectrometers, detectors and associated equipment, 1996-10, Vol.380 (1), p.419-422, Article 419
• Main Authors: Rossi, M, Baldazzi, G, Querzola, E, Guidi, G, Scannavini, M.G, Chirco, P, Zanarini, M, Casali, F, Azevedo, S
• Format: Article
• Language: English
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/S0168-9002(96)00385-3

Cadmium zinc telluride (Cd 0.8Zn 0.2Te) is nowadays one of the most promising room temperature semiconductors for X- and γ-ray detection. Indeed, its physical characteristics make this detector very suitable for operating under high-intensity fluxes, such as those produced by linear accelerators. For this reason, CdZnTe has been chosen for the set-up of a tomographic facility based on 12-MeV linear accelerator. This system is a first generation tomograph; it has already been used for preliminary phantoms image acquisition, showing rather good imaging capabilities. The polychromaticity of the source may induce severe beam-hardening artifacts in the final tomographic images. Extensive experimental studies have been carried out to optimize correction algorithms able to reduce such artifacts. A set of images of relevant samples have been acquired in order to evaluate the relationship between the absorption coefficients and the resulting CT numbers.