Field-Deployable, High Resolution, High Pressure Xenon Gamma Ray Spectrometer

73096S03-I There is a need for the detection and characterization of specific radioisotopes for homeland security, treaty verification, and customs surveillance. Unfortunately, current high resolution spectrometers require operating temperatures at liquid nitrogen levels and are highly expensive to maintain; other spectrometers that 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. This project will develop a rugged, self-contained, high resolution gamma ray spectrometer that is both portable and field-deployable. High pressure Xenon gas will be used as the spectroscopic medium. An innovative method of incorporating a reflective coating inside the detector will be developed, so that scintillation light emission from the Xenon gas can be used to correct for geometric signal dispersion in the detector, thereby providing high immunity to acoustic effects. A prototype, high pressure Xenon gamma ray detector will be constructed in Phase I. This detector will then be tested to determine energy resolution, overall sensitivity, and lifetime stability. Based on the test results, the prototype design will be modified for a full-scale device in Phase II. Commercial Applications and Other Benefits as described by awardee: The high resolution, high pressure Xenon gamma ray spectrometer should be applicable to the detection of illicit radioactive substances in the areas of homeland security, treaty verification, customs regulation, and environmental monitoring. The device will be safe, sensitive, low cost, easy to maintain, portable, and ideal for use in field operations. The detector itself also could be adapted for medical imaging purposes.