Open AccessDistinctive features of the structure of current sheets formed in plasma in three-dimensional magnetic configurations with an X line (a review)
Author(s) -
A. G. Frank
Publication year - 2021
Publication title -
uspehi prikladnoj fiziki
Language(s) - English
Resource type - Journals
ISSN - 2307-4469
DOI - 10.51368/2307-4469-2021-9-6-464-478
Subject(s) - current sheet , magnetic field , current (fluid) , plasma , plasma sheet , electric current , field (mathematics) , excitation , condensed matter physics , physics , mechanics , magnetohydrodynamics , magnetosphere , mathematics , quantum mechanics , pure mathematics , thermodynamics
A review is presented on experimental results related to investigation of distinctive features of the structure and evolution of plasma current sheets formed in three
dimensional (3D) magnetic configurations with an X line, in the presence of a longitudinal magnetic field component (guide field) directed along the X line. It is shown that formation of a plasma current sheet results in enhancement of the guide field within the sheet. The excessive guide field is maintained by plasma currents that flow in the transverse plane relative to the main current in the sheet. As a result, the structure of the currents becomes three-dimensional.
Increasing the initial value of the guide field brings about a decrease of compression into the sheet of both the electric current and plasma. This effect is caused by changing the pres-
sure balance in the sheet when an excessive guide field appears in it. Deformation of plasma current sheets in 3D magnetic configurations, namely, an appearance of asymmetric
and tilted sheets, results from excitation of the Hall currents and their interaction with the guide field. It is shown that the formation of current sheets in 3D magnetic configurations
with an X line is possible in a relatively wide, but limited range of initial conditions