Investigation of the deuterium distribution in a JET limiter using the nuclear microprobe and ion beam slope cutting

For studying deuterium depth profiles in surfaces of JET (Joint European Torus) limiters, a new deuterium profiling method was developed and used. A smooth 10deg slope plane on the specimen was produced by ion beam slope cutting using a 10 keV Kr ion beam. To detect deuterium the nuclear reaction 2H(12C,p)13C was used at E(12C3+)=7.5 MeV. The very narrow proton peak could be clearly separated from the background of the spectra. For measuring the lateral and vertical deuterium distribution the 12C beam of the Rossendorf 5 MV tandem accelerator was focussed to about 6 μm and scanned across the specimen. The preliminary results show a deuterium distribution up to a depth of about 5 μm in a carbon limiter. (orig.)