Study of solid-conversion gaseous detector based on GEM for high energy X-ray industrial CT

Article type: Research Article

Authors: Zhou, Rifeng | Zhou, Yaling

Affiliations: ICT Research Center, The Key Lab. for Opto-electronic Technology and Systems of Ministry of Education, University of Chongqing, Chongqing, China

Note: [] Corresponding author: Rifeng Zhou, ICT Research Center of Chongqing University, No.174 ShaZheng Street, Chongqing 400044, China. Tel.: +86 23 8639 4813; E-mail: zurifg@163.com

Abstract: The general gaseous ionization detectors are not suitable for high energy X-ray industrial computed tomography (HEICT) because of their inherent limitations, especially low detective efficiency and large volume. The goal of this study was to investigate a new type of gaseous detector to solve these problems. The novel detector was made by a metal foil as X-ray convertor to improve the conversion efficiency, and the Gas Electron Multiplier (hereinafter "GEM") was used as electron amplifier to lessen its volume. The detective mechanism and signal formation of the detector was discussed in detail. The conversion efficiency was calculated by using EGSnrc Monte Carlo code, and the transport course of photon and secondary electron avalanche in the detector was simulated with the Maxwell and Garfield codes. The result indicated that this detector has higher conversion efficiency as well as less volume. Theoretically this kind of detector could be a perfect candidate for replacing the conventional detector in HEICT.

Keywords: High energy X-ray, industrial computer tomography, gaseous detectors, GEM

DOI: 10.3233/XST-140426

Journal: Journal of X-Ray Science and Technology, vol. 22, no. 3, pp. 299-307, 2014