High Resolution X-Ray Spectroscopy for Diagnostics of Single Tokamak Discharges

We report on an experiment which has been used to measure soft X-ray line emission spectra from highly charged impurity elements in the hot plasma of the Alcator C tokamak. These measurements shall serve as a diagnostic of plasma parameters: the temperature (of ions and electrons), the electron and impurity ion densities, and charge state distributions. Results from the initial measurements of the He- and H-like spectra of S and Cl are presented as well as spectra from molybdenum in charge states between Mo 28+ and Mo 32+ . Dependencies of the measured spectra on plasma parameters are provided. The aim of this experiment is to conduct broad-band time-resolved spectroscopic diagnosis of tokamak plasmas. To this end we discuss pertinent requirements of spectrometer performance and the development of a new position sensitive X-ray detector system.