Generation of electrostatic solitary waves in the plasma sheet boundary layer

Abstract

Generation of electrostatic solitary waves (ESWs) in the plasma sheet boundary layer in terms of electron-acoustic solitons and double layers is proposed. The plasma sheet boundary layer is treated as a multicomponent magnetized plasma consisting of background electrons, counter-streaming electron beams and ions. The model is based on the multifluid equations and the Poisson equation, and uses the Sagdeev pseudo-potential technique. For the plasma parameters at the time of broadband electrostatic noise in the plasma sheet boundary layer observed by Cluster on 22 September 2004, the model predicts solitons/double layer with electric field ∼(0.01-30) mV/m with time durations ∼(0.1-4.5) ms. Such short electric field pulses, when Fourier transformed to the frequency domain, can appear as broadband electrostatic noise in the frequency range of ∼220 Hz to 10 kHz. It is proposed that the model can be a good candidate for explaining the generation of broadband electrostatic noise in the plasma sheet boundary layer.