Underground Mine Detection Using X-Ray Backscatter Imaging

We propose to design and develop a new x-ray detector system for use in underground mine imaging applications. The detector system will be designed to operate with a pencil-beam sca m ing x-ray source, and will detect the Compton interacted radiation that is scattered back toward the X-ray source. It will image horizontal views of thin layers of the underground structure. The detector we propose to use is cadmium zinc telluride (CdO-gZnO.2Te) ' which is a solid state detector. It is insensitive to vibrations and temperature change, consumes low power, is densely stacked, and has a response time better than 1 Ksec. The detector system will be designed to image layers of the ground with a voxel resolution of 2 cm cubes. The source-detector system will be insensitive to height variations, and will be designed to optimize backscatter radiation from the surface to 6 inches deep in the ground. This system could be successfully implemented with dual energy imaging if it determined necessary or desirable during Phase I. In Phase I we will evaluate experimentally a bench setup and image thin layers of soil. We will report the findings and present our reco m mendations for the development of a full system.