@article{oai:repo.qst.go.jp:00080287, author = {Oya, Yasuhisa and Masuzaki , Suguru and Tokitani, Masayuki and Nakata, Moeko and Sun, Fei and Oyaidzu, Makoto and Isobe, Kanetsuku and Asakura, Nobuyuki and Otsuka, Teppei and Widdowson, Anna and Likonen, Jari and Rubel, Marek and Contributors, JET and Masuzaki , Suguru and Asakura, Nobuyuki and Otsuka, Teppei}, issue = {4}, journal = {Fusion Science and Technology}, month = {Aug}, note = {Hydrogen isotope retention and chemical state for the tiles exposed to plasma in the JET–ITER-like wall (ILW) during two campaigns in 2011–2012 (first campaign, ILW-1) and 2015–2016 (third campaign, ILW-3) were studied and compared by means of X-ray photoelectron spectroscopy and thermal desorption spectroscopy. In both campaigns the upper part of the inner divertor tiles was the deposition-dominated area, while erosion was observed on the outer divertor tiles. Therefore, higher deuterium retention was found on the inner divertor tiles. The major D desorption peak for the inner divertor tiles from ILW-3 was located at the temperature range of 470°C to 520°C, which was higher than measured after ILW-1: 370°C to 430°C. The XPS analyses showed the formation of a BeO layer on the ILW-3 inner divertor tiles, while after ILW-1 the layers also contained a significant amount of carbon. Deuterium retention was reduced toward the outer divertor tiles. The differences could be related to the difference in the power level in the two campaigns.}, pages = {439--445}, title = {Comparison of Hydrogen Isotope Retention in Divertor Tiles of JET with the ITER-Like Wall Following Campaigns in 2011–2012 and 2015–2016}, volume = {76}, year = {2020} }