High sensitivity imaging Thomson scattering for low temperature plasma

A highly sensitive imaging Thomson scattering system was developed for low temperature (0.1–10eV) plasma applications at the Pilot-PSI linear plasma generator. The essential parts of the diagnostic are a neodymium doped yttrium aluminum garnet laser operating at the second harmonic (532nm), a laser beam line with a unique stray light suppression system and a detection branch consisting of a Littrow spectrometer equipped with an efficient detector based on a “Generation III” image intensifier combined with an intensified charged coupled device camera. The system is capable of measuring electron density and temperature profiles of a plasma column of 30mm in diameter with a spatial resolution of 0.6mm and an observational error of 3% in the electron density (ne) and 6% in the electron temperature (Te) at ne=4×1019m−3. This is achievable at an accumulated laser input energy of 11J (from 30 laser pulses at 10Hz repetition frequency). The stray light contribution is below 9×1017m−3 in electron density equivalen...