Option of ICRF ion heating scenario in Large Helical Device

摘要

Specific behavior of confining magnetic field in Large Helical Device suppresses tokamak-like ion heating scheme for ion cyclotron plasma heating with outside ICRF antenna. Respectively, the basic ICRF scenario with D(H) plasma will heat the electrons, as have been shown in stellarator CHS experiments. To overcome this difficulty, we propose to use in LHD high magnetic field side antenna operating in 'heavy' minority heating scenarios H(D) or H(He-3), where brackets indicate minority ions. We show analytically that predominantly heated in this scenario will be the minority ions, subsequently transferring their energy to bulk proton ions. Another proposed scenario operates with 'light' ion minority scheme like D(H), but with addition of third isotope ion component like C(sup 13), Ne(sup 21), Li(sup 7), etc.. These third isotope ions eliminate degeneration of second harmonic frequency with fundamental frequency of minority ion(H) or second harmonics of deuterium ions. Isotopic ions will be heated due to a mode converted Ion Bernstein Waves close to second harmonic ion cyclotron layer ((omega)=2(omega)(sub ci)). (author)