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.