Plasma Density Measurement on an SCU-PSI Device via a CO₂ Dispersion Interferometer

Abstract

A new CO₂ dispersion interferometer (DI) was commissioned on the linear device at Sichuan University for the plasma surface interaction (SCU-PSI) [1]. The SCU-PSI device can generate a plasma pulse with very high density and a short duration. The DI system measured the plasma densities in several plasma discharges with rapid density changes. The results show a high correlation to other diagnostics such as the plasma current signal measured using a Rogowski coil. The line-density resolution of the system is 6.3 × 10¹⁷/m². The time resolution is 0.05 ms.