Cesium environmental monitoring system for assaying temporal changes in atomic disintegration products using laser-induced breakdown spectroscopy

Abstract

In this work, a new method for real-time in-situ environmental monitoring of measured radioactive elements is presented. Currently, germanium semiconductor detectors are used for the analysis of radioactive materials. Germanium semiconductor detectors exhibit sensitivities much higher than those exhibited by other analytical instrumentation techniques. However, the equipment is lab-based and cannot address the need for on-site monitoring. Moving radioactive samples is strictly legally prohibited for safety reasons. The frequency of use is limited by the facility installation space, workforce supply considerations regarding safety, legal considerations for carrying and storing radioactive samples, and waste disposal methods. The presented method using laser-induced breakdown spectroscopy (LIBS) offers an affordable sensing system that can be applied at point-of-use for environmental analyses to provide an indication of impending problems. The applicable range of conventional LIBS, which has been used only to determine the elemental composition, is expanded to obtain an estimate of the isotope ratio by measuring the variation due to temporal changes in the atomic disintegration products. This method takes full advantage of LIBS, such that no pretreatment of the measured sample is required. In this work, a confirmation test for the LIBS measurement of cesium and barium based on the results of the disintegration of cesium is demonstrated as part of a preliminary survey for developing a monitoring system for actual radioactive materials.