Polaris 3-D Position-Sensitive CdZnTe Gamma-Ray Imaging Spectrometers

摘要

Three-dimensional position-sensitive CdZnTe gamma-ray detector technology, pioneered by University of Michigan, can provide high resolution gamma-ray spectroscopy close to that of high purity germanium detectors, under ambient temperature operation. It can image intensities of gamma-ray sources in real time with high imaging efficiency. Each Polaris system consists of eighteen 2×2×1.5 cm CdZnTe detectors, with an overall energy resolution about 0.9% FWHM at 662 keV and can image gamma rays in the entire 4π field of view without any blind angle. They can detect and locate gamma-ray sources an order of magnitude weaker than natural gamma-ray background, making them ideal for detecting, identifying and locating gamma-emitting sources in applications of national security, international nuclear non-proliferation, homeland security, radiation monitoring in nuclear power plants, nuclear waste clean-up, and medical imaging. The spectroscopic performance of two generations of Polaris systems constructed by University of Michigan group will be presented in the energy range of 30 keV up to 3 MeV. This project has been jointly funded by US Department of Defense - Defense Treat Reduction Agency and Department of Energy NA-22 Office.