[Three-dimensional position-sensitive germanium detectors]. Annual report for EMSP Project Number 65015

This study focuses on the radioactive materials characterization needs of DOE's decontamination and decommissioning effort. Gamma-ray imaging and spectroscopy together form a potentially powerful tool for the passive, non-destructive and non-intrusive identification and spatial mapping of contaminated structures. Germanium position-sensitive gamma-ray detectors offer the advantage of excellent energy resolution required for clear isotopic identification combined with potentially high spatial resolution. The authors propose a program of research to develop three-dimensional position-sensitive germanium detectors with the ultimate goal of improving image resolution without cameras. With the addition of depth-of-interaction sensing to conventional two-dimensional position-sensitive detectors, they will be able to greatly reduce the image degradation effects caused by Compton scattering and parallax, thereby increasing the resolving power of the detectors. The technology developed will form the basis for the design and fabrication of future high-performance gamma-ray imaging cameras