The depositions of hydrogen isotopes on carbonised fusion reactor walls

Results from recent tokamak experiments, with a carbonised surface covering the first wall, could give information on the surface content of hydrogen isotopes in the surface layer of a fusion reactor, and the risk for surface embrittlement. An important tool for such studies is the use of long term samples exposed in larger tokamaks of today for extended periods. Varying plasma conditions and disruption events is the cause of an ununiform deposition distribution. The total surface inventory of hydrogen isotopes can be estimated from these results. (author)