Xenon International is a fully automated system designed to collect, separate, enrich, quantify, and perform nuclear counting on radioxenon isotopes. Detection of Xenon isotopes is a proven method for distingui​​shing nuclear explosions, especially underground explosions, from earthquakes. Xenon International incorporates lessons learned during the International Noble Gas Experiment (INGE) and two decades of xenon monitoring to quantify isotopes 131mXe, 133Xe, 133mXe and 135Xe.  Its design increases sensitivity for​ minor xenon isotopes, increases sampling frequency, and improves system reliability and performance. ​​

The system operates and transmits results unattended, while also allowing local and remote manual control. Xenon International is designed to stringent requirements* that make it an improved-performance, next-generation-system for use in nuclear explosion monitoring networks, such as the International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty Organization 

The Xenon International was accepted b​y the Preparatory Commission of the CTBTO as a certified noble gas system for the IMS radionuclide stations, achieving a 97% data availability.  ​​​​

The Xenon International is a compact system consisting of eight functions. These internal functions include the following: 

  • Air Intake and Compression
  • Air Drying
  • Cooling and Collection
  • Separations
  • Purification and Concentration 
  • Nuclear Detection (Beta-Gamma Spectroscopy)
  • Xenon Quantification
  • Xenon Archiving
 Xenon International

External to the Xenon Interna​tional system is the uninterruptible power supply ,and a nitrogen generator . Xenon International uses a nitrogen generator to eliminate replacing expendable carrier-gas cylinders. ​

Xenon International is a result of collaboration between Pacific Northwest National Laboratory (PNNL) and Teledyne Brown Engineering (TBE) to build a system that meets stringent requireme​​​nts​ for a robust and maintainable instrument which incorporates excellence in science, engineering, and manufacturing. System specifications are as follows: ​


System Details

Size 81 cm wide x 124 cm deep x 192 cm high
Weight 1225 Kg
Power 208 VAC (160-275 volt), 50.60 Hz, 30 amp circuit
Collection Time 6 hours
Air Flow 100 L/min
Xenon Volume in Detector 2.5 cc
Measurement Time 12 hours (4 nuclear detector​s)
Minimal Detectable Concentration (MDC) 0.15 mBq/m3 (threshold) for 133Xe, 133mXe, and 131mXe
Minimal Detectable Concentration (MDC) 0.5 mBq/m3 (threshold) for 135Xe

​​​​​​​​​​​​​Xenon International   

*Requirements for Xenon International: Revision 1, Pacific Northwest National Laboratory, PNNL-22227 (Rev 1), doi:10.2172/1122330 ​​