2023-03-24T06:40:47Zhttps://nifs-repository.repo.nii.ac.jp/?action=repository_oaipmhoai:nifs-repository.repo.nii.ac.jp:000103952021-09-10T07:10:09Z00008:00032
Effect of Collisionality and Radial Electric Field on Bootstrap Current in LHD (Large Helical Device)engbootstrap currentstellaratorheliotronneoclassical currentcollisionalityradial electric fieldMHD equilibriumhttp://hdl.handle.net/10655/2603Research Paper K.Y., "Watanabe N., Nakajima M., Okamoto K., Yamazaki Y., Nakamura M.", Wakatani"The bootstrap current reduces in more collisional regime, and in the stellarator/heliotron it is predicted that the neoclassical current proportional to radial electric field exists when electrons and ions belong to different regimes of collisionality. To evaluate the bootstrap current in stellarator/heliotron in the whole range of collisionality from the collisionless l/mu regime to the Pfirsch-Schluter regime, a new connection formula has been proposed. We have applied this connection formula to the LHD plasmas which belongs to some collisionality regimes and obtained finite beta MHD equilibria including the bootstrap current. For LHD plasmas such as ECRH (T_i < < T_e) in electron root, the bootstrap current with electric potential twice as large as electron temperature reduces to about 1/5 ~ 2/3 of that with zero electric potential. Them MHD equilibrium configuration significantly changes depending on collisionality and radial electric field even for the same beta value of LHD plasmas."Research Report NIFS-Series1994-06-010915-633x2016-03-07