POLARIZATION OF IMPURITY EMISSION-LINES FROM A TOKAMAK PLASMA

The visible-uv spectrometer was equipped with a double refracting calc ite plate for the purpose of resolving a spectral line into the two li nearly polarized components and observing these components simultaneou sly. Relative intensities of these components have been measured for h eliumlike carbon and berylliumlike oxygen impurity lines from the WT-3 tokamak plasma at Kyoto University. In the joule heating mode, for tr ansition from the joule heating to the lower-hybrid current drive mode , and for application of the electron cyclotron healing, changes in th e relative intensities were found, which indicated that these lines we re polarized. Implications of the polarization of the emission lines f rom plasma are discussed.