http://arxiv.org/abs/2208.06965
Over the past decade, Boozer has argued that three-dimensional (3D) magnetic reconnection fundamentally differs from two-dimensional (2D) reconnection due to the fact that the separation between any pair of neighboring field lines almost always increases exponentially over distance in a 3D magnetic field. This feature makes 3D field-line mapping chaotic and exponentially sensitive to small non-ideal effects; consequently, 3D reconnection can occur without intense current sheets. We test Boozer’s theory via ideal and resistive reduced magnetohydrodynamic simulations of the Boozer-Elder coronal loop model driven by sub-Alfv\’enic footpoint motions. Our simulation results do not support Boozer’s theory. The ideal simulation shows that Boozer and Elder significantly under-predict the intensity of current density due to missing terms in their reduced model equations. Furthermore, resistive simulations of varying Lundquist numbers show that the maximal current density scales linearly with the Lundquist number, as opposed to Boozer’s prediction of a logarithmic dependence.
Y. Huang and A. Bhattacharjee
Tue, 16 Aug 22
36/74
Comments: N/A