[show abstract][hide abstract] ABSTRACT: Depth profiling measurements of tritium in carbon samples have been performed during the past seven years at the AMS facility
installed at the Rossendorf 3 MV Tandetron. The samples have been cut from the inner walls of the fusion experiments ASDEX-upgrade/Garching
and JET/Culham. The tritium content of the samples from JET required a dedicated AMS facility to prevent any contamination
of the versatile 3 MV Tandetron. On the basis of an air-insulated 100 kV tandem accelerator equipped with a gas stripper an
AMS facility exclusively devoted to tritium depth profiling was installed, tested and used for routine measurements. After
additional successful tests employing diamond-like carbon (DLC) stripper foils at this accelerator, another small and compact
100 kV tandem accelerator with SF6 insulation and a DLC stripper has been installed at the AMS facility. Results obtained with the different tandem accelerators
[show abstract][hide abstract] ABSTRACT: Detritiation by heat treatment of graphite or carbon fibre composite (CFC) tiles retrieved from the Tokamak Fusion Test Reactor (TFTR) was assessed using the standard and well proved technique of full combustion combined with liquid scintillation analysis. Complete carbon tiles were heated in a oven to 500 °C in air for one hour at Princeton Plasma Physics Laboratory (PPPL) and sent to Tritium Laboratory Karlsruhe (TLK) for surface and depth profile analysis. Coring/full combustion technique performed on the treated and untreated tiles, both graphite and CFC, has shown that only the tritium held close to the surface (few tens μm) is efficiently released by baking in air while the bulk tritium is almost unaffected. Therefore, baking the tile under air, even at 500 °C, does not detritiate the bulk.
[show abstract][hide abstract] ABSTRACT: Recent results on measurements of tritium and other hydrogen isotopes in first wall materials of large tokamaks are discussed and evaluated. Data on the in situ and ex situ release of tritium from plasma facing components under different conditions are assessed.
[show abstract][hide abstract] ABSTRACT: Tritium depth profiling by accelerator mass spectrometry has been performed at the Rossendorf 3 MV Tandetron. Tritium particles are counted after the accelerator using a semiconductor detector, while deuterium and other light elements are simultaneously measured with the Faraday cup between the injection magnet and the accelerator. Depth profiles have been measured in carbon samples cut from the first wall tiles of the Garching fusion experiment ASDEX-Upgrade and of the European fusion experiment JET, Culham/UK. Tritium contents in the JET samples were up to six orders higher than in samples from ASDEX-Upgrade. Tritium beam currents from samples with high tritium content were measured partly in the Faraday cup before the accelerator. A dedicated tritium AMS facility with an air-insulated 100 kV tandem accelerator is under construction.
Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms 01/2000; 172:655-658. · 1.27 Impact Factor