scholarly journals Electron-acoustic solitary waves and double layers with an electron beam and phase space electron vortices in space plasmas

2005 ◽  
Vol 110 (A1) ◽  
Author(s):  
W. F. El-Taibany
Keyword(s):  
Electron Beam ◽  
Phase Space ◽  
Solitary Waves ◽  
Double Layers ◽  
Space Plasmas ◽  
Electron Acoustic

scholarly journals Electrostatic Solitary Structures in Space Plasmas: Soliton Perspective

Plasma ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 681-731
Author(s):  
Gurbax Singh Lakhina ◽  
Satyavir Singh ◽  
Rajith Rubia ◽  
Selvaraj Devanandhan
Keyword(s):  
Phase Space ◽  
Energetic Electron ◽  
Theoretical Models ◽  
Double Layers ◽  
Space Plasmas ◽  
Electrostatic Waves ◽  
Lunar Wake ◽  
Bgk Modes ◽  
Theoretical Predictions ◽  
Electron Acoustic

Occurrence of electrostatic solitary waves (ESWs) is ubiquitous in space plasmas, e.g., solar wind, Lunar wake and the planetary magnetospheres. Several theoretical models have been proposed to interpret the observed characteristics of the ESWs. These models can broadly be put into two main categories, namely, Bernstein–Green–Kruskal (BGK) modes/phase space holes models, and ion- and electron- acoustic solitons models. There has been a tendency in the space community to favor the models based on BGK modes/phase space holes. Only recently, the potential of soliton models to explain the characteristics of ESWs is being realized. The idea of this review is to present current understanding of the ion- and electron-acoustic solitons and double layers models in multi-component space plasmas. In these models, all the plasma species are considered fluids except the energetic electron component, which is governed by either a kappa distribution or a Maxwellian distribution. Further, these models consider the nonlinear electrostatic waves propagating parallel to the ambient magnetic field. The relationship between the space observations of ESWs and theoretical models is highlighted. Some specific applications of ion- and electron-acoustic solitons/double layers will be discussed by comparing the theoretical predictions with the observations of ESWs in space plasmas. It is shown that the ion- and electron-acoustic solitons/double layers models provide a plausible interpretation for the ESWs observed in space plasmas.

scholarly journals Double layers in the downward current region of the aurora

2003 ◽  
Vol 10 (1/2) ◽  
pp. 45-52 ◽  
Author(s):  
R. E. Ergun ◽  
L. Andersson ◽  
C. W. Carlson ◽  
D. L. Newman ◽  
M. V. Goldman
Keyword(s):  
Magnetic Field ◽  
Electron Beam ◽  
Phase Space ◽  
Electric Field ◽  
Electric Fields ◽  
Double Layers ◽  
Parallel Electric Field ◽  
Electrostatic Waves ◽  
Current Region ◽  
Decisive Evidence

Abstract. Direct observations of magnetic-field-aligned (parallel) electric fields in the downward current region of the aurora provide decisive evidence of naturally occurring double layers. We report measurements of parallel electric fields, electron fluxes and ion fluxes related to double layers that are responsible for particle acceleration. The observations suggest that parallel electric fields organize into a structure of three distinct, narrowly-confined regions along the magnetic field (B). In the "ramp" region, the measured parallel electric field forms a nearly-monotonic potential ramp that is localized to ~ 10 Debye lengths along B. The ramp is moving parallel to B at the ion acoustic speed (vs) and in the same direction as the accelerated electrons. On the high-potential side of the ramp, in the "beam" region, an unstable electron beam is seen for roughly another 10 Debye lengths along B. The electron beam is rapidly stabilized by intense electrostatic waves and nonlinear structures interpreted as electron phase-space holes. The "wave" region is physically separated from the ramp by the beam region. Numerical simulations reproduce a similar ramp structure, beam region, electrostatic turbulence region and plasma characteristics as seen in the observations. These results suggest that large double layers can account for the parallel electric field in the downward current region and that intense electrostatic turbulence rapidly stabilizes the accelerated electron distributions. These results also demonstrate that parallel electric fields are directly associated with the generation of large-amplitude electron phase-space holes and plasma waves.

Electron acoustic solitary waves in a magnetized plasma with nonthermal electrons and an electron beam

2016 ◽  
Vol 23 (8) ◽  
pp. 082310 ◽  
Author(s):  
S. V. Singh ◽  
S. Devanandhan ◽  
G. S. Lakhina ◽  
R. Bharuthram
Keyword(s):  
Electron Beam ◽  
Solitary Waves ◽  
Magnetized Plasma ◽  
Nonthermal Electrons ◽  
Electron Acoustic

Ion- and electron-acoustic solitons and double layers in multi-component space plasmas

2011 ◽  
Vol 47 (9) ◽  
pp. 1558-1567 ◽  
Author(s):  
G.S. Lakhina ◽  
S.V. Singh ◽  
A.P. Kakad
Keyword(s):  
Double Layers ◽  
Space Plasmas ◽  
Electron Acoustic
Sign in / Sign up

Export Citation Format

Share Document