@misc{oai:repo.qst.go.jp:00072772,
 author = {Hatanoa, Y. and Yumizurua, K. and Masuzaki, S. and Tokitani, M. and Asakura, Nobuyuki and Isobe, Kanetsugu and Hayashi, Takumi and Koivuranta, S. and Likonen, J. and Matsuyama, M. and Baron-Wiechec, A. and Widdowson, A. and Heinola, K. and Jachmich, S. and Rubel, M. and contributors, JET and 朝倉 伸幸 and 磯部 兼嗣 and 林 巧},
 month = {May},
 note = {Tritium (T) distributions in divertor tiles retrieved from the JET-ITER Like Wall (ILW) after the 1st (2011–2012) and 2nd (2013–2014) experimental campaigns were examined by measuring energy spectra of X-rays induced by β-rays from T. Disk specimens cored from the W-coated CFC divertor tiles (Tiles 1, 4, 6, 7 and 8) were analysed using a silicon-drift detector (SDD) equipped with an ultra-thin window (70 nm-thick Si3N4) at QST, Rokkasho. Analysis using a SDD with a conventional window (8 μm-thick Be) was performed at VTT. The former SDD was used to detect characteristic X-rays of Be together with those of W, while the latter was more suitable for non-destructive depth profiling by analysing X-ray energy spectra. A majority of T currently present in the JET vacuum vessel is produced by DD fusion reactions [D + D → T (1.01 MeV) + H (3.03 MeV)]. Therefore, T is present as a minor isotope of hydrogen in the vessel. A part of T produced is implanted into the tiles at high energy (~MeV), while a remaining part of T is thermalized in the plasma. Strong peaks of Be KαX-rays were observed for the horizontal and upper vertical parts of Tile 1 due to heavy co-deposition of T with Be eroded from the main chamber wall. Intensity of Be KαX-rays was below detection limit for other tiles because of far smaller thickness or absence of Be deposition layer. In contrast, the intensity of W MαX-rays was almost uniform though it was somewhat high at the positions close to the main plasma (the horizontal parts of Tiles 1 and 8). Depth profile analyses showed that T penetrated into depths up to 0.5–4 μm. These observations indicated the implantation of high energy T into the W layers.  Exceptionally high intensity of X-rays (and also γ-rays) was observed at the shadowed region of Tile 4, though thermal desorption spectrometry showed relatively small D retention in this region. The mechanisms underlying this exceptional T accumulation will be discussed in the presentation by taking account of the results of microstructural analysis., 16th International Conference on Plasma-Facing Materials and Components for Fusion Applications (PFMC-16)},
 title = {Tritium Analysis of Divertor Tiles Used in JET ITER-like Wall Campaigns by Means of β-ray Induced X-ray Spectrometry},
 year = {2017}
}