Internal transport barrier driven by redistribution of energetic ions
نویسنده
چکیده
Alfvén instabilities excited by energetic ions are used as a means to reduce the central magnetic shear in a tokamak via redistribution of energetic ions. When the central magnetic shear is low enough, ballooning modes become stable for any plasma pressure gradient and an internal transport barrier (ITB) with a steep pressure gradient can exist. This mechanism can sustain a steady-state ITB as demonstrated by experimental data from the DIII-D tokamak. It can also produce a shear in toroidal and poloidal plasma rotation. Possible application of this technique to use the energetic α particles for improvement of burning plasma performance is discussed. PACS numbers: 52.55.Pi, 52.35.Bj, 52.35.Py (Some figures in this article are in colour only in the electronic version) AQ1
منابع مشابه
Alpha-channeling simulation experiment in the DIII-D tokamak.
Alfvén instabilities can reduce the central magnetic shear via redistribution of energetic ions. They can sustain a steady state internal transport barrier as demonstrated in this DIII-D tokamak experiment. Improvement in burning plasma performance based on this mechanism is discussed.
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