Current sheet formation and dissipation in general X-point topologies

摘要: We consider cylindrical, X-type magnetic equilibria specified by flux functions of the form r n cos(nθ) with ≥ 2. It is shown that excess energy associated arbitrary disturbances comprises three components: a frictional component can be dissipated any mechanical damping; topological (M S ) only resistive reconnection; and residual determined distribution normal through outer boundary. demonstrate long macroscopic current sheets should naturally develop in compressible plasmas, even for weak finite amplitude disturbances. In particular, simplest sheet length scales as L 2n ∼ M