Hybrid (particle in cell-fluid) simulation of ion-acoustic soliton generation including super-thermal and trapped electrons

Journal Article · Mon Aug 15 00:00:00 EDT 2011 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3622208· OSTI ID:22043381

Nopoush, M; Abbasi, H ^[1]

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1. Faculty of Physics, Amirkabir University of Technology, P. O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

The present paper is devoted to the simulation of the nonlinear disintegration of a localized perturbation into an ion-acoustic soliton in a plasma. Recently, this problem was studied by a simple model [H. Abbasi et al., Plasma Phys. Controlled Fusion 50, 095007 (2008)]. The main assumptions were (i) in the electron velocity distribution function (DF), the ion-acoustic soliton velocity was neglected in comparison to the electron thermal velocity, (ii) on the ion-acoustic evolution time-scale, the electron velocity DF was assumed to be stationary, and (iii) the calculation was restricted to the small amplitude case. In order to generalize the model, one has to consider the evolution of the electron velocity DF for finite amplitudes. For this purpose, a one dimensional electrostatic hybrid code, particle in cell (PIC)-fluid, was designed. It simulates the electrons dynamics by the PIC method and the cold ions dynamics by the fluid equations. The plasma contains a population of super-thermal electrons and, therefore, a Lorentzian (kappa) velocity DF is used to model the high energy tail in the electron velocity DF. Electron trapping is included in the simulation in view of their nonlinear resonant interaction with the localized perturbation. A Gaussian initial perturbation is used to model the localized perturbation. The influence of both the trapped and the super-thermal electrons on this process is studied and compared with the previous model.

• OSTI ID: 22043381
• Journal Information: Physics of Plasmas, Vol. 18, Issue 8; Other Information: (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
AMPLITUDES
COMPARATIVE EVALUATIONS
DISTRIBUTION FUNCTIONS
DISTURBANCES
EQUATIONS
GAUSSIAN PROCESSES
INTERACTIONS
ION ACOUSTIC WAVES
IONS
ONE-DIMENSIONAL CALCULATIONS
PERTURBATION THEORY
PLASMA
PLASMA SIMULATION
SOLITONS
THERMODYNAMICS
TRAPPED ELECTRONS
TRAPPING
TRAPS