An investigation on the 133Xe global network coverage for the International Monitoring System of the Comprehensive Nuclear-Test-Ban Treaty

Abstract

The radionuclides part of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) global network of International Monitoring System (IMS) is based on the measurement of particles and radioactive noble gases. Forty radionuclide stations are going to be equipped with radioxenon measurement components to monitor the nuclear explosion signatures around the world. Global coverage of the noble gas IMS stations has been investigated using atmospheric transport modelling. Two years of worldwide release for a hypothetical 1-kt underground nuclear explosion and detection of 133Xe in the IMS radioxenon station locations are considered. The present and completed status were supposed as two different scenarios to estimate the daily coverage of the network. The calculated quantities were evaluated corresponding to the whole latitude/longitude grid in image-base and numerical patterns. Although the fluctuation of daily coverage is varying in time, the cumulative minimum amounts were indicated that North America has stable high coverage in the present arrangement. Moreover, after the completion of the network, this aspect will be expanded to the middle part of the Northern Hemisphere as well as the west region of the Southern Hemisphere. Finally exploring the cumulative maximum daily coverage is denoted that adding the non-operational stations to the current network has a great influence on the 20 S - 90 N latitudes to 0–180 W longitudes and about 50% effect on the network coverage (NC) of the north of Europe, South Atlantic, and Oceania. However, it has almost no impact on the values of the limited area around the middle east part of the Pacific Ocean.