High Pressure Xenon Detector for Compton Imaging Applications

There is a need for the detection and characterization of specific radioisotopes in the interest of homeland security, treaty verification, and customs. Current high resolution spectrometers require operating temperatures at liquid nitrogen levels and are highly expensive to maintain, and other spectrometers which operate at room temperatures do not afford the resolution required to distinguish and identify many radioisotopes of interest. Further, many devices are subject to acoustic interferences which significantly degrade their performance in field operations. Thus, there is a need for a rugged, self-contained, high resolution gamma ray spectrometer which is both portable and field-deployable. High pressure Xenon gas will be used as a spectroscopic medium for building a portable, room temperature, high resolution gamma ray spectrometer. An innovative method of incorporating a reflective coating inside the detector will be developed so VUV scintillation light emission from the Xenon gas can be used to correct for geometric signal dispersion in the detector, producing a spectroscopic resolution approaching 0.45% at 662 keV in a device with high immunity to acoustic effects. At the end of the project, a full-scale, rugged, portable, self-contained, high pressure, and high resolution Xenon spectrometer will be available for testing in field operations.