Quasi-adiabaticity in bifurcated current sheets

Quasi-adiabaticity in bifurcated current sheets

Kinetic theory and simulation of collisionless tearing in bifurcated current sheets

Observations from the Earth’s geomagnetic tail have established that the current sheet is often bifurcated with two peaks in the current density. These so-called bifurcated current sheets have also been reported in a variety of simulations and often occur in conjunction with significant temperature anisotropy. In this work, a new self-consistent Vlasov equilibrium is developed that permits both...

A model of the bifurcated current sheet

[1] Recent Geotail and Cluster observations revealed that thin current sheets in the near-Earth tail may have a bifurcated structure. In some cases the electrons are found to dominate the current. We present a generalization of the Harris current sheet equilibrium, which reproduces these features. The model ion distribution contains an additional element, viz. the quasi-adiabatic invariant of t...

Current sheets from Ulysses observation

Current sheet is a significant source of solar wind MHD turbulence intermittency. It has long been recognized that these structures can arise from non-linear interactions of MHD turbulence. Alternatively, they may also be relic structures in the solar wind that have a solar origin, e.g., magnetic walls of flux tubes that separate solar wind plasma into distinct parcels. Identifying these struct...

Magnetoacoustic wave propagation in current sheets

Magnetoacoustic waves in a Harris neutral current sheet are investigated. The magnetic field strength, Alfvén speed, sound speed and plasma density vary continuously across the structure. The sheet supports body, surface and hybrid modes. Two surface modes exist (a kink and a sausage). In addition, fundamental and harmonic body waves are found when their phase speeds approach the maximum Alfvén...