Аннотация:
Infinite families of new exact solutions to the Beltrami equation with a non-constant
$\alpha (\mathbf{x})$ are derived. Differential operators connecting the steady axisymmetric Klein – Gordon
equation and a special case of the Grad – Shafranov equation are constructed. A Lie semi-group
of nonlinear transformations of the Grad – Shafranov equation is found.
Ключевые слова:ideal fluid equilibria, force-free plasma equilibria, Klein – Gordon equation, Yukawa
potential, Beltrami equation.