The Lithium Tokamak Experiment Thomson Scattering Diagnostic

The Lithium Tokamak Experiment (LTX) is a spherical tokamak designed to study the low-recycling regime though the use of a liquid-lithium coated shell conformal to the last closed flux surface. A low recycling rate is expected to flatten core electron temperature profiles, raise edge temperatures, and strongly affect electron density profiles. A Thomson scattering diagnostic is used to measure radial $T_{e}$ and $n_{e}$ profiles. The system uses a 15 J, 30 ns pulsed ruby laser and measures profiles of up to 16 radial points on the horizontal midplane at a single temporal point for each discharge. Scattered light is imaged though a spectrometer into an intensified CCD. Two transmission gratings are available for the spectrometer to increase temperature range. In order to protect optical windows from becoming coated with lithium, the system uses automated shutters and gate valves. Preliminary measurements will be presented.