High-pressure xenon detector to identify and monitor nuclear materials

Development of new gamma-ray spectrometers will help successfully fulfill international agreements related to nonproliferation of nuclear materials. This paper describes a high pressure Xe cylindrical ionization chamber with a shielding mesh for energies in the 0.1-5 MeV range. The detector holds two liters of high-purity Xenon gas with a density of 0.5 g/cm(3). The energy resolution of the detector is similar to 3.0 % at 662 keV, and similar to 2.0 % at 1.17 MeV. The sensitivity of a system containing four such six liter detectors will be equivalent to the sensitivity of a NaI crystal with a diameter of 250 mm and a height 70 mm.