Multiple Laser System for High-Resolution Thomson Scattering Diagnostics on the EAST Tokamak

A multiple laser system for high-resolutionThomson scattering diagnostics has been developed in ASIPP.The system includes laser controller, high-energy lasers, transferoptics, focusing lens, and beam alignment system. Each Nd:YAGlaser can be fired for measuring the electron temperature anddensity profiles periodically at 10 Hz, and consequently, fourlasers can be fired alternately for an average measurementfrequency of 40 Hz. In order to measure transient events, they willbe fired in rapid succession, and produce a burst of pulses. Afterabout one month trial running on the superconducting EASTtokamak, the system was proven to be capable of working wellwith improved time resolution. The system setup and analysis aredescribed in detail, as well as the measurement capability, spatialand temporal resolutions 7 mm and tens kilohertz, respectively.So as to monitor and adjust the laser beam, two beam positionsensitive detectors are installed in the 40-m beam path. Finally,the experimental results are presented.