Experimental and analytical procedures related to the application of nitrogen-15 isotope for material migration studies have been developed and used for tracer experiments in the TEXTOR and ASDEX-Upgrade tokamaks in order to assess the retention of nitrogen in plasma-facing components made of graphite and tungsten. The surface study was performed by time-of-flight heavy ion elastic recoil detection analysis and by means of nuclear reaction analysis based on the 15N(p,?a)12C process. In both tokamaks nitrogen retention has exceeded 10% of the injected gas. In ASDEX-Upgrade the largest fraction of 15N has been detected on protruding parts near the injection port, while around 4% has been found in the divertor. The ASDEX-Upgrade results have also been modeled. Helium trapping has been measured in deposits containing tungsten and nitrogen.
|Publication status||Published - 2014|
|MoE publication type||A1 Journal article-refereed|
- plasma physics
- nuclear physics
- tracer techniques
- fuel retention
Petersson, P., Rubel, M., Possnert, G., Brezinsek, S., Kreter, A., Möller, S., Hakola, A., Mayer, M., Miettunen, J., Airila, M., Makkonen, T., Neu, R., Rohde, V., Team, ASDEX-U., & Team, TEXTOR. (2014). Overview of nitrogen-15 application as a tracer gas for material migration and retention studies in tokamaks. Physica Scripta, (T159), . https://doi.org/10.1088/0031-8949/2014/T159/014042