Thomson Scattering Measurements of Plasma Turbulence Near Quarter-Critical Density in a Carbon-Dioxide Laser - Gas Target Plasma.
Abstract
Ruby laser Thomson scattering is used to obtain data on plasma density and temperature. This diagnostic revealed a strongly nonthermal level of plasma turbulence at one half the CO2 laser frequency, which was attributed to the parametric decay of the CO2 laser light into plasma waves. The theory of laser driven parametric instabilities relevant to this experiment is reviewed, with particular attention paid to the two plasmon parametric decay. It is theoretically demonstrated that the threshold condition for this decay is relaxed if the pump wave is obliquely incident on the density gradient. Thomson scattering theory relevant to this experiment is summarized and the effect of temporal and spatial variations in the plasma density is calculated.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- May 1978
- Bibcode:
- 1978PhDT........21S
- Keywords:
-
- Physics: Fluid and Plasma; Energy;
- Dense Plasmas;
- Laser Heating;
- Plasma Turbulence;
- Plasmons;
- Thomson Scattering;
- Ionized Gases;
- Plasma Density;
- Plasma Diagnostics;
- Plasma Waves;
- Ruby Lasers;
- Plasma Physics