Penetration and radial force balance in field-reversed configurationudwith large rotating magnetic field

摘要

A field-reversed configuration FRC is formed by applying a rotating magnetic field RMF muchudlarger than the axial magnetic field to a cylindrical glass vacuum chamber filled with 10 Pa argonudgas without a preionization. The FRC with the plasma density 2.21019 m−3, the temperatureud8.0 eV, the separatrix length 0.45 m, and the separatrix radius 0.035 m is sustained for the notablyudlong period of 40 ms. It is observed that the antenna current which produces the RMF is reduced byudabout half after the FRC is formed. The interaction between the plasma and the antenna circuitudincreases the antenna resistance and changes the inductance of the antenna so that the circuitudbecomes nonresonant. The RMF is sufficiently large to fully penetrate to the center during the periodudand drive the current with a rigid rotor profile. The RMF is shown to play a major role in sustainingudthe plasma pressure. © 2008 American Institute of Physics.