Thomson Scattering Applied to a Noisy Radiative Plasma

Abstract

Thomson scattering with a 1.5 ms long pulse mode 20 J ruby laser has been applied to a radiative argon plasma with electron densities Itg from 2.5 lola ma to 1.5 lozo m-3 and an electron temperature Te of about 3 eV. Photon counting techniques have been used. The accuracy of ne and Te to be reached is about 5% after 10 shots. The signal to noise ratio SIN has been optimized by the use of optical filters and a special purpose grating. The effects of these elements on SIN have been calculated. The entrance angle, transmission and quantum efficiency have also been optimized. A comparison between 5 possible h e r systems, including a normal mode and a Qswitched mode ruby laser, has been carried out.

On the Pressure Balance and Plasma Transport in Cylindrical Magnetized Arcs

“…Thomson scattering (50 J Ruby laser as source and a six-channels polychromator with a concave holographic grating) [19]. ~ Fi, F a 1 Doppler width-and shift-measurements \v 0l , u-ftj with a pressure scanned Fabry-Perot.…”