Large amplitude inertial compressional Alfvenic shock and solitary waves, and acceleration of ions in magnetohydrodynamic plasmas

Abstract

Large amplitude inertial compressional Alfvenic shock and solitary waves in magnetohydrodynamic plasmas are investigated. Dispersive effect caused by non-ideal electron inertia currents perpendicular to the ambient magnetic field can balance the nonlinear steepening of waves leading to the formation of a soliton. A Sagdeev-potential formalism is employed to derive an energy-balance like equation. The range of allowed values of the soliton speed, M (Mach number), plasma beta (ratio of the plasma thermal pressure to the pressure in the confining magnetic field), and electron inertia, wherein solitary waves may exist, are determined. Depth of the potential increases with increasing the Mach number and plasma beta, however decreases with the increasing electron inertia. The height of soliton increases with increasing in Mach number and decreases with plasma beta. And with increasing electron inertial length, the width of soliton increases. The electron-ion collisional dissipation results a dissipative inertial compressional Alfven wave, which can produce a shock like structure and can efficiently accelerate ions to the order of the local Alfven velocity. The shock height increases with the increasing collision frequency, but shock height decreases with increasing plasma beta. (C) 2013 AIP Publishing LLC.