Compton imaging with the PorGamRays spectrometer

The PorGamRays project aims to develop a portable gamma-ray detection system with both spectroscopic and imaging capabilities. The system is designed around a stack of thin Cadmium Zinc Telluride (CZT) detectors. The imaging capability utilises the Compton camera principle. Each detector is segmented into 100 pixels which are read out through custom designed Application Specific Integrated Circuits (ASICs). This device has potential applications in the security, decommissioning and medical fields. This work focuses on the near-field imaging performance of a lab-based demonstrator consisting of two pixelated CZT detectors, each of which is bonded to a NUCAM II ASIC. Measurements have been made with point Ba-133 and Co-57 sources located similar to 35 mm from the surface of the scattering detector. Position resolution of similar to 20 mm FWHM in the x and y planes is demonstrated. (C) 2011 Elsevier B.V. All rights reserved.