Current sheet formation at the various 3D magnetic configurations

Investigation of magnetic energy accumulation by the current sheet (CS) formation at the various 3D magnetic configurations is of a fundamental importance for the magnetic reconnection problem. The variety of 3D configurations was realized experimentally by the superposition of two magnetic fields. One is the planar 2D field with a null-line at z-axis and the field gradient h: rvec B, [Bx; By; Bz] = [h·x; - h·y; 0] (1) The second is the axial-symmetrical (z-axis) field either with null-point O (cusp configuration), or with Bz-component. The cusp field may be written in the vicinity of the null-point in the following way: rvec Bc = [hr·x; hr·y; - 2hr·z] (2) hr is the radial field gradient. The superposition of (1) and (2) results in a new 3D configuration with a null-point: rvec B = rvec Bq + rvec Bc = [(h+hr)·x; - (h-hr); - 2hr·z] (3)