摘要
In the previous analytical description of the neoclassical polarization current effect on the neoclassical tearing modes （NTMs）, it is usually assumed that the magnetic island is much larger than the finite-ion-banana-width （FBW）. This assumption is questionable when the experimentally observed seed island width of the NTMs is comparable to the FBW. We introduce a simple and direct theoretical method to investigate the FBW effect on the neoclassical polarization contribution to the NTM evolution in collisional plasmas. The results show that, the FBW effect can strongly modify the neoclassical polarization current profile near the island separatrix, and thus weaken its probably stabilizing effect on the NTMs.
In the previous analytical description of the neoclassical polarization current effect on the neoclassical tearing modes （NTMs）, it is usually assumed that the magnetic island is much larger than the finite-ion-banana-width （FBW）. This assumption is questionable when the experimentally observed seed island width of the NTMs is comparable to the FBW. We introduce a simple and direct theoretical method to investigate the FBW effect on the neoclassical polarization contribution to the NTM evolution in collisional plasmas. The results show that, the FBW effect can strongly modify the neoclassical polarization current profile near the island separatrix, and thus weaken its probably stabilizing effect on the NTMs.
基金
supported by the National Magnetic Confinement Fusion Science Program of China (Nos.2011GB105002,2014GB107001 and 2014GB124004)
National Natural Science Foundation of China(Nos.11175057 and 11275061)
