Abstract:
The article continues the series of works on the numerical study of the stability of equilibrium plasma configurations held by the magnetic field in Galatea traps using the specific example of a toroidal Galatea Belt straightened into a cylinder. Numerical investigation of the behavior with time of small perturbations in the linear approximation is carried out in a refined equilibrium model: the boundary value problem with the Grad-Shafranov equation in the non-bonded region of the cylinder takes into account the real geometry of current conductors immersed in it. Calculations of the behavior with time of twodimensional perturbations and their detailed analysis drew attention to the specificity of the previously observed rather large velocity values. They are concentrated only at the outer boundary of configurations, are bounded by any small density values, do not penetrate deep into the main configuration of the plasma, and do not grow with time. This type of “instability” does not belong to the traditional Lyapunov type of instability and is apparently less dangerous in stability issues. Calculations of three-dimensional Belt perturbations were performed for their corrugated harmonics along the cylinder axis and showed instability in the Lyapunov sense at any values of the oscillation frequency. The quantitative patterns of instability depend on the mentioned frequency and are presented by the results of the calculations.
