Laser induced ablation spectroscopy for in situ characterization of the first wall on EAST tokamak

An in situ measurement and the control of fuel retention in the vacuum-vessel will be an important aspect for the safe operation of nuclear fusion devices. Laser-Induced Ablation Spectroscopy (LIAS) is an attractive option with promising capabilities for in situ characterization of fuel retention and co-deposition during plasma discharges.

In this work, an in situ LIAS wall diagnostic system is developed for real-time during discharge diagnosis of the first wall on the EAST superconducting tokamak. A dedicated timing system, which offers the function of multiple temporal settings with high time resolution for LIAS measurement during longpulse discharges, is successfully commissioned. The experimental setup of the LIAS system for the characterization of the first wall on EAST is presented in detail.