Effect of steady magnetic field on laser-induced breakdown spectroscopic characterization of EAST-like wall materials

Abstract Our recent investigations were focused on the feasibility of the LIBS method proposed for EAST under vacuum conditions as well as with a magnetic field. Aluminum (replaced Be)–lithium alloys were used as a substitute for a uniform lithium deposition layer on the first wall. Detailed information of divertor tiles (multi-element doped graphite) and aluminum–lithium alloys were obtained by analyzing the spectra from 200 to 980 nm. With the magnetic field (0.94 T), various line emissions obtained from the constituents of samples shown an enhancement (>2 times) in intensity due to the increase in the effective plasma density and temperature as a result of magnetic confinement. The effect of magnetic field on the emission intensity of LIBS at the different pressure (1.0 × 10 − 5 –1000 mbar) would help us to develop a quantitative LIBS approach to monitor impurity deposition and fuel retention on the first wall.

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