Fiber-coupled LIBS analysis using a microchip laser in a harsh environment

Oba, Hironori; Akaoka, Katsuaki; Karino, Takahiro; Wakaida, Ikuo; Tamura, Koji*; Nakanishi, Ryuzo*; Sakamoto, Kan*; Taira, Takunori*

no journal, , 

Development of remote inspection and elemental analysis methods in a harsh radiation environment is required, such as inspection of the nuclear fuel debris at the bottom of the post-accident nuclear reactor (Tokyo Electric Power Company, Fukushima Daiichi Nuclear Power Plant). Laser-induced breakdown spectroscopy (LIBS) has been utilized as an effective qualitative and quantitative analytical method for elemental analysis. Inspecting the damaged reactor vessels requires a longer fiber-optic (FO) cable, which significantly attenuates the delivered laser energy by absorption and scattering in the fiber. We report on the first trial of our FO-LIBS system using the microchip laser (MCL) to identify and quantify elements in surrogate nuclear fuel debris under gamma irradiation, the results of trials on surrogate debris analysis, containing uranium oxide, using the MCL, and the results of 100 m-long fiber-delivered LIBS.