Localized plasma polarimetry based on circular modes conversion: theoretical prerequisites and practical limitations

摘要

The method of localized polarimetric measurements based on the phenomenon of modes conversion near the orthogonality point between the electromagnetic beam and one of the helical magnetic lines in a tokamak plasma is discussed. A simple model of toroidal magnetized plasma is suggested, which allows one to analyze the applicability of localized polarimetry for the ITER project. It is shown that an acceptable localization of polarimetric measurements of about 0.3 m can be achieved for very high densities of order N-e = 10(17) cm(-3), which are significantly higher than the plasma densities, N-e = 10(14)-10(15) cm(-3), envisaged for the ITER project.