On the possibility of tritium measurement in a Tokamak by a laser technique

In a Tokamak vacuum vessel, plasma - wall interaction phenomena lead to the trapping of tritium in the Plasma Facing Components (PFC). Safety evaluation studies have pointed out the risks due to the accumulation of tritium that could significantly impact the operation of a reactor like ITER. Therefore, the evaluation of the tritium quantity trapped in the PFC is of crucial interest in fusion research. A promising technique to achieve this goal is the spectroscopic analysis of the plasma produced by laser ablation of material, known as Laser-Induced Breakdown Spectroscopy (LIBS). In the present work, LIBS analyses are performed on copper samples and PFC tiles extracted from Tore Supra. The influences of laser pulse duration and wavelength on the properties of the induced plasmas are investigated. (authors)