Laser induced breakdown spectroscopy application in joint European torus

A. Semerok (1, 2) , D. L'Hermite (2, 1) , J.-M. Weulersse (2, 1) , J.-L. Lacour (1, 2) , G. Cheymol (2, 1) , M. Kempenaars (3) , N. Bekris (4) , C. Grisolia (5)

1 SEARS - Service d'études analytiques et de réactivité des surfaces
2 CEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire)
3 EURATOM/CCFE Fusion Association
4 EUROfus Program Management Unit PMU
5 IRFM - Institut de Recherche sur la Fusion par confinement Magnétique

The results on the first successful application of Laser Induced Breakdown Spectroscopy (LIBS) for remote in situ diagnostics of plasma facing components (a deposited layer on a divertor tile) in Joint European Torus (JET) are presented. The studies were performed with an available JET EDGE LIDAR laser system. For in-depth analysis of deposited layers on JET divertor tiles, a number of laser shots were applied onto the same divertor place without laser beam displacement. The spectral lines of D, CII and impurity elements (CrI, BeII, …) were identified in a wide spectral range (400-670 nm). With the increase in a number of laser shots applied onto the same divertor place, we observed consecutive changes in spectral line intensities of deuterium, carbon, and impurities with the appearance of spectral lines of tungsten substrate (WI). In-depth analysis of deposited layers on JET divertor tiles was made on the basis of the spectral line behaviour in reference to the applied laser shots. The possibility of surface cartography with laser beam displacement on the tile surface was demonstrated as well. Based on the results obtained, we may conclude that LIBS method is applicable for in situ remote analysis of deposited layers of JET plasma facing components.

Domaines: Physique Nucléaire Théorique [nucl-th]; Physique Nucléaire Expérimentale [nucl-ex]

A. Semerok, D. L'Hermite, J.-M. Weulersse, J.-L. Lacour, G. Cheymol, et al.. Laser induced breakdown spectroscopy application in joint European torus. Spectrochimica Acta Part B: Atomic Spectroscopy, 2016, 123, pp.121-128. ⟨10.1016/j.sab.2016.08.007⟩. ⟨cea-02428833⟩