Abstract
A higher than baseline atmospheric concentration of the radioactive fission product Kr-85 is considered to be the best indicator of clandestine plutonium separation. Additionally, its high volatility makes it suitable for detecting leaks in nuclear waste containers and damaged fuel cladding. A spectrometer for ultra-trace analysis is currently under development and will be optimised for atmospheric monitoring of Kr-85. This device is based on an adapted form of collinear resonance ionisation spectroscopy, a technique developed at ISOLDE-CERN for performing precision measurements on exotic nuclei. The motivation for this device is explored, along with an overview of progress and future developments.