Tritium distribution in JET Mark IIA type divertor tiles analysed by BIXS

Abstract Distribution of tritium concentrations on the surface and in the bulk (up to 1 mm in depth) in a complete poloidal set of divertor tiles exposed to D–T plasma shots in JET was measured by β-ray-induced X-ray spectrometry (BIXS). The observed X-ray spectra showed that tritium distribution was different not only from tile to tile but also highly non-uniform in each individual tile. The peaks of bulk tritium concentration obtained by BIXS are correlated with the corresponding one obtained previously by other methods. For the first time, tritium depth profiles in the plasma-facing surface of complete divertor tiles were obtained by BIXS and they can be classified by four types of a tritium depth profile.