The ARIX-03F mobile semiautomatic facility for measuring low concentrations of radioactive xenon isotopes in air and subsoil gas

The facility is used to measure concentrations of fission-product xenon nuclides (131mXe, 133mXe, 133Xe, and 135Xe) in the air (the subsoil gas) under field conditions. It is composed of two independently functioning parts—a portable sampler and a unit comprising sample-preparation and measuring modules. A method of low-temperature adsorption on activated charcoal by means of a coolant is used to extract xenon from air streams. To obtain xenon devoid of detectable amounts of radon, gases liberated from the adsorber by thermal desorption are passed through a system of traps. The β-γ coincidence method is used to measure the radionuclide concentrations in xenon samples. When processing air (or subsoil gas) samples with a volume of 6 m3 and measuring their spectra over 18 h, the minimum detectable concentration of the dominating radionuclide (133Xe) is 0.9 mBq/m3. The complex of equipment can be housed in a minivan and is intended to detect radioxenon anomalies at presumed places of clandestine nuclear explosions.