Comparison of optimized ECCD for different launch locations in a next step tokamak reactor plasma

摘要

Utilization o electron cyclotron radiofrequency sources for current drive and the stabiliza- tion of neoclassical tearing models (NTMs) in next step devices rests on the current density and current drive efficiency attainable. Optimization is reported of electron cyclotron driven current density and current drive efficiency with respect to source frequency as well as toroidal and poloidal launch angles for two launcher positions: an 'upper port' position above the midplane and a 'midplane' position at the height of the magnetic axis.