Fuel Retention in JET ITER-Like Wall from Post-Mortem Analysis
Selected Ion Beam Analysis techniques applicable for detecting deuterium and heavier impurities have been used in the post-mortem analyses of tiles removed after JET ITER-Like Wall campaign. Over half of the retained fuel was measured from the divertor region. Highest figures for fuel retention were obtained from regions with thickest deposited layers, i.e. in the inner divertor on top of Tile 1 and on High Field Gap Closure tile, which resides deep in the plasma scrape-off layer. Least retention was found in the main chamber high erosion region, i.e. in the mid-plane of Inner Wall Guard Limiter. Fuel retention values were found typically to vary with deposition layer thicknesses. The reported retention values support the observed decrease in fuel retention obtained with previous gas balance experiments.