Ion and neutron beam analyses of hydrogen isotopes

Kubota, Naoyoshi; Ochiai, Kentaro; Kutsukake, Chuzo; Kondo, Keitaro*; Shu, Wataru; Nishi, Masataka; Nishitani, Takeo

Hydrogen isotopes play important roles in the fuel recycling, the plasma condition etc. at the surface region of plasma facing components. The Fusion Neutronics Source (FNS) of Japan Atomic Energy Research Institute has started microanalysis studies for fusion components since 2002 by applying the beam analyses. In this study, we have measured tritium depth profiles of TFTR tiles exposed to the deuterium-tritium plasma to reveal the hydrogen isotope behavior at the surface region using some microscopic techniques for material analyses at FNS. As the result of the deuteron nuclear reaction analysis, four kinds of elements; deuterium, tritium, lithium-6 and lithium-7, were identified from the energy spectra. Using the spectra, depth profiles of each element were also calculated. The tritium profile had a peak at 0.5 micron, whereas the deuterium and lithium profiles were uniform from the surface to 1.0 micron depth. In addition, the surface region of the TFTR tile has retained the tritium more than one order of magnitude in the bulk.