The formation of electric current sheets in a high-conductivity three-dimensional plasma configuration is studied in the neighborhood of the critical points of the magnetic field. First, with the help of a Clebsch variable representation, the propagation of magnetohydrodynamic (MHD) waves in azimuthally symmetric current-free configurations is investigated. Exact solutions of the MHD equations that describe the self-similar evolution of a magnetic configuration near a critical point are presented. Then, the nonlinear plasma evolution is simulated with an MHD code. The excitation of an electric current at the boundary of the computational region results in a self-consistent plasma flow and in the change of the structure of the magnetic field. No electric current sheet is formed when both the equilibrium configuration and the perturbations are azimuthally symmetric. (C) 2002 American Institute of Physics.
Current sheet formation in three-dimensional magnetic configurations
PEGORARO, FRANCESCO
2002-01-01
Abstract
The formation of electric current sheets in a high-conductivity three-dimensional plasma configuration is studied in the neighborhood of the critical points of the magnetic field. First, with the help of a Clebsch variable representation, the propagation of magnetohydrodynamic (MHD) waves in azimuthally symmetric current-free configurations is investigated. Exact solutions of the MHD equations that describe the self-similar evolution of a magnetic configuration near a critical point are presented. Then, the nonlinear plasma evolution is simulated with an MHD code. The excitation of an electric current at the boundary of the computational region results in a self-consistent plasma flow and in the change of the structure of the magnetic field. No electric current sheet is formed when both the equilibrium configuration and the perturbations are azimuthally symmetric. (C) 2002 American Institute of Physics.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
