Vasudevan Mukunth, a science blogger from Chennai, India talks in detail about the detection of different radioxenon isotopes by the International Monitoring System (IMS) after the North Korea nuclear tests, with reference to the recent radioxenon pledge.
“Why choose to track radioxenon and not anything else?
Xenon-135 has a half-life of 9.14 hours, which means it’s around long enough for it to be spotted in the atmosphere, but not long enough so that its presence masks more recent emissions. Second, it’s noble, i.e. chemically inert. Third, xenon-133 and xenon-135 are produced in significant quantities – some 5-7% of total emissions – in the aftermath of a nuclear explosion. Fourth, xenon-133 and xenon-135 are not produced naturally.”