Study on dynamic behaveier of ablated species in gas environment

Miyabe, Masabumi   ; Oba, Masaki ; Jung, K.; Akaoka, Katsuaki ; Wakaida, Ikuo  

In order to analyze isotopic composition of fuel debris generated in melted reactor core, a remote analytical method is developed based on laser ablation technique. In this method, the interaction between ablated and gas species affects time evolution of the plume structure, which also affects on analytical performance. Thus we investigate time evolution of ablated and gas species using resonance fluorescence and absorption techniques. As a result, it was found that the interaction between gas and ablated species leads complicated three dimensional structure. In particular, in the case of atmospheric air condition, it was found that many particulates and clusters are produced at the contact layer between gas and plume, and the neutral atoms stays near the center of the clusters. These findings is of great importance for future development of various laser-ablation-based analytical techniques.