Xenon International is a fully automated, unattended system designed to collect, separate, enrich, quantify, and perform nuclear counting on radioxenon isotopes, as well as transmit data using two way communications. 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 (CTBT).
Detection of xenon isotopes is a proven and important method for distinguishing nuclear explosions from earthquakes, and detecting undeclared underground nuclear explosive testing. The radioxenon isotopes 131mXe, 133Xe, 133mXe and 135Xe are used in identifying nuclear explosions which make them the focus of current noble gas detection systems. A Xenon International system incorporates the important lessons learned during the previous 10-year International Noble Gas Experiment (INGE). Its redesigned subsystems have increased sensitivity to minor xenon isotopes, increased sampling frequency, improved system reliability and performance, key performance improvements of this new system.
The Xenon International system consists of six different physical subsystems built into a single compact instrument. These internal subsystems include the following:
- Air intake and compressor subsystem
- Air dryer subsystem
- Collection trap and pre-cool recirculation loop subsystem
- Separation subsystem
- Enrichment subsystem
- Nuclear detection (beta-gamma coincidence) and quantification subsystem.
External to the Xenon International system is the uninterruptible power supply (the UPS is the smaller white unit in the figure above), and a nitrogen generator (the larger white unit in the figure). Xenon International uses a nitrogen generator to eliminate replacing expendable carrier-gas cylinders.
Size: 45-in. wide x 32-in. deep x 80-in. high
Collection time: 6 hours
Measurement time: 12 hours
Minimal detectable concentration (MDC):
- 0.15 mBq/m3 (threshold) for 133Xe, 133mXe, and 131mXe
- 0.5 mBq/m3 (threshold) for 135Xe
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 requirements for a robust and maintainable instrument which incorporates excellence in science, engineering, and manufacturing. Two prototypes (one at PNNL and one at TBE) are undergoing performance testing.
Teledyne Brown Engineering
*Requirements for Xenon International: Revision 1, Pacific Northwest National Laboratory, PNNL-22227 (Rev 1), doi:10.2172/1122330