Impurity transport and plasma-wall interaction of the heliotron E plasma

Impurities can play an important role in the production of reactor-grade plasmas, through radiation, enhanced resistivity and dilution of the working gas, possibly affecting the energy and particle transports of the plasma. It is therefore necessary to understand the origins and subsequent transport process of impurities in the plasma. While many experiments have been performed in tokamaks, few direct measurements of plasma-wall interaction and impurity transport have been done on helical systems. There is considerable speculation that impurities are important in the overall dynamics of the plasma of helical systems, especially during neutral beam heating experiments