Simulated evolution of three-dimensional magnetic nulls leading to generation of cylindrically-shaped current sheets

摘要

The performed magnetohydrodynamic simulation examines the importance of magnetofluid evolution, which naturally leads to current sheets in the presence of three-dimensional (3D) magnetic nulls. The initial magnetic field is constructed by superposing a 3D force-free field on a constant axial magnetic field. The initial field supports 3D magnetic nulls having the classical spine axis and the dome-shaped fan surface and exerts non-zero Lorentz force on the magnetofluid. Importantly, the simulation identifies the development of current sheets near the 3D magnetic nulls. The morphology of the current sheets is similar to a cylindrical surface where the surface encloses the spine axis. The development is because of favorable deformation of magnetic field lines constituting the dome-shaped fan surface. The deformation of field lines is found to be caused by the flow generated by magnetic reconnections at current sheets which are located away from the cylindrically shaped current sheets. Published by AIP Publishing.