Rabia Amour

• Dr
• Research Associate at University of Sciences and Technology Houari Boumediene

We investigate the effects of non-extensivity (q), non-thermality (α), obliqueness (l z ), the strength of the magnetic field (ω c ), and dust grain temperature (σ d ) on the basic features (viz., amplitude, width, velocity, and soliton energy) of obliquely propagating dust-acoustic solitary waves (DASWs) in a magnetized dusty plasma, which consist...

In this paper, the role of dust grain's gravitational force on the nonlinear dust‐acoustic oscillations in non‐Maxwellian dusty plasma is analyzed. It is shown that increasing the number of non‐thermal ions causes the diminution of the electrostatic potential's amplitude and a reduction in the number of oscillations introduced by the gravitational...

In this article, oblique propagation of coherent and dissipative ion-acoustic solitary waves (IASWs) in the presence of $\kappa $ -Gurevich distributed electrons in two-component magnetized viscous plasma is investigated. Therefore, a new $\kappa$ -Gurevich distribution function describing the evolution of adiabatically trapped suprathermal ele...

In this article, we present a new 3-D, collisional, stationary, and magnetized plasma sheath model based on fluid equations. Numerical calculations in weakly electronegative oxygen plasma at low pressure containing graphite dust grains with a size distribution have been carried out. The obtained results reveal that the sheath thickness decreases as...

A first theoretical attempt is made to understand the characteristics of dust acoustic shock waves (DASWs) in a polarized electron-depleted plasma with a mixed nonextensive high energy–tail ion distribution and to examine the impact of the generalized nonthermal polarization force on DASWs in an electron-depleted dusty plasma. First, a short numeri...

The present article explores the effects of nonthermal nonextensive polarization force on nonlinear dust acoustic (DA) soliton and its energy. The nonthermal (or Cairns) polarization force (PF) acting on dust grains in a three-component unmagnetized dusty plasma is then revisited within the theoretical framework of the Tsallis statistical mechanics...

The influence of adiabatically trapped nonthermal polarization force on dressed dust acoustic solitary waves (DDASWs) in non-Maxwellian complex plasma is investigated. In particular, we focus our analysis on modifications induced by the Cairns–Gurevich polarization force and higher-order corrections on the main characteristics of the dust acoustic...

Dans cette communication nous analysons l'influence de la force de polarisation non thermique piégée sur les ondes acoustique poussiéreuses associé à un plasma poussiéreux non collisionnel, composé d'électrons maxwelliens, de grains de poussière chargés négativement et d'ions non thermiques piégés. Pour ce faire, une distribution tridimensionnelle...

A first theoretical attempt is made to investigate the adiabatically trapped suprathermal ions effect on dust acoustic (DA) solitons in electron-depleted dusty plasmas. Our investigation is motivated by space and laboratory plasma observations of plasmas containing suprathermal particles, resulting from long-tailed distributions, combined with trap...

Both linear and weakly nonlinear dust‐acoustic (DA) solitons propagation are revisited in the presence of adiabatically trapped‐nonextensive ions. A physically relevant distribution (called Tsallis‐Gurevich ions distribution) is outlined here for the first time. The effect of particle trapping has been taken into account, resulting in a new express...

The oblique propagation of low-frequency solitary waves is considered in a polarized magnetized complex plasma with adiabatically trapped nonthermalions. A Cairns–Gurevich distribution is adopted, and the polarization force associated with our plasma model is applied. In addition, the appropriate modified Korteweg–de Vries (mK-dV) equation, in whic...

The charge fluctuation induced solitary wave anomalous damping in a charge varying dusty plasma with ions following a Cairns–Gurevich distribution is investigated. To examine a such phenomenon, the exact Cairns–Gurevich ion charging current and the associated dust charge frequency are derived here for the first time. In addition, the appropriate mo...

The problem of dust-ion-acoustic (DIA) solitons is addressed in an electronegative collisionless dusty plasma with the presence of trapped-nonthermal electrons. To do this, we revisited the Cairns-Gurevich distribution that describes, concurrently, the evolution of the energetic electrons and those trapped in the plasma potential and analytically e...

In this paper, the problem of large amplitude dust acoustic (DA) solitons has been addressed in a charge varying dusty plasma with ions following a Cairns-Gurevich distribution. Based on the orbit motion limited approach, the correct Cairns-Gurevich ion charging current is presented for the first time. The expression relating the variable dust char...

The head-on collision between two ion-acoustic solitons (IASs) is studied in pair ions plasmas with hybrid Cairns–Tsallis-distributed electrons. The chosen model is inspired from the experimental studies of Ichiki et al. [Phys. Plasmas 8, 4275 (2001)]. The extended Poincaré–Lighthill–Kuo (PLK) method is employed to obtain the phase shift due to the...

The effect of trapped non-thermal polarization force on low-frequency solitary waves (dust acoustic solitons) is addressed in a collisionless complex plasma. For this purpose, we have firstly redefined the three-dimensional Cairns–Gurevich distribution that describes, simultaneously, the evolution of the energetic ions and those trapped in the plas...

The effect of suprathermal polarization force on both linear and weakly nonlinear dust‐acoustic solitary structures in a three‐component dusty plasma is investigated. For this purpose, a new expression of the polarization force acting on dust particles that include the electronic suprathermal effect is derived. The results are applied to two differ...

A first theoretical attempt is made to investigate the effects of the trapped nonthermal polarization force on dust-acoustic solitons in collisionless dusty plasmas. For this purpose, a three-dimensional Cairns–Gurevich distribution, that describes, simultaneously, the evolution of the energetic ions and those trapped in the plasma potential well,...

A theoretical study has been carried out of obliquely propagating dust acoustic solitary waves in a magnetized multi-component dusty plasma which consists of fluid dust grains, nonextensive ions, and Maxwellian electrons. Our plasma model is inspired from the experimental study of Bandyopadhyay et al. (Phys Rev Lett 101:065006, 2008). The reductive...

The contribution of higher order corrections to the DA soliton energy in the presence of nonthermal ions is investigated. Our plasma model is inspired from the experimental study of Bandyopadhyay et al. [P. Bandypadhyay, G. Prasad, A. Sen, P.K. Kaw, Phys. Rev. Lett. 101, 065006 (2008)]. Using the approach based on the expansion of Sagdeev potential...

The problem of dust acoustic solitons is addressed in an unmagnetized collisionless dusty plasma with ions satisfying a Cairns–Gurevich distribution. A new type of density that describes, simultaneously, the evolution of the energetic ions and those trapped in the plasma potential well is outlined. Both highly and weakly nonlinear waves are investi...

Ce polycopié de cours et de travaux pratiques regroupe un certain nombre de notions de base sur l’algorithmique. Ce cours d’algorithmique, destiné particulièrement aux étudiants de première année Sciences de la Matière (SM), Sciences Technologies (ST) et Maths informatiques (MI). Le présent polycopié est scindé en deux grandes parties. La première...

Ce polycopié de cours et de travaux pratiques regroupe un certain nombre de notions de base sur l’algorithmique. Ce cours d’algorithmique, destiné particulièrement aux étudiants de première année Sciences de la Matière (SM), Sciences Technologies (ST) et Maths informatiques (MI). Le présent polycopié est scindé en deux grandes parties. La première...

Dynamique non lin eaire des plasmas Cours et exercices, Master 2 Physique Théorique, parcours: Théorie et Modélisation en Physique des Plasmas

Dynamique non lin eaire des plasmas Cours et Exercices, Master 2 Physique Théorique, parcours: Théorie et Modélisation en Physique des Plasmas

Dust is an ubiquitous component of space and astrophysical environments, occurring for example in planetary rings, comets and the Earth's ionosphere [1]. Dusty plasmas are known to support a wide variety of ultra low-frequency wave modes. The most well studied of such modes are the so called dust-acoustic wave (DAW) [2] and dust ion-acoustic wave (...

Ce polycopié constitue la première mouture d'une introduction à la dynamique faiblement non linéaire d'un plasma qui (sommairement) se définit comme étant un gaz électrifié dont les atomes sont dissociés en ions à charge positive et électrons à charge négative. Il constitue une partie du cours "Dynamique Non Linéaire des Plasmas (DNLP)" que nous di...

Study of linear or nonlinear wave phenomena in electron-positron (e-p) plasmas attracted much attention during the last decade due to their frequent occurrence in active galactic nuclei, pulsar magnetosphere and in solar atmosphere. The electron-positron (e-p) plasmas are also believed to play an important role in understanding the early universe....

The charge variation induced nonlinear dust-acoustic wave damping in a charge varying dusty plasma with nonextensive ions is considered. It is shown that the collisionless damping due to dust charge fluctuation causes the nonlinear dust acoustic wave propagation to be described by a damped Korteweg-de Vries (dK-dV) equation the coefficients of whic...

Over the last few years, a great deal of attention has been paid to nonextensive statistic mechanics based on the deviations of Boltzmann-Gibbs-Shannon (BGS) entropic measure. A suitable nonexten-sive generalization of the BGS entropy for statistical equilibrium was first recognized by Renyi and subsequently proposed by Tsallis [1], suitably extend...

The model of Cairns et al. [Geophys. Res. Lett. 22, 2709 (1995)] is generalized. A physically meaningful nonextensive nonthermal velocity distribution is outlined. As the nonextensive character of the nonthermal electrons increases, the distribution shoulders may become less or more prominent and high-energy states are less or more probable than in...

An attempt is made to study variable charge dust acoustic (DA) solitons within the theoretical framework of the Tsallis statistical mechanics. The correct nonextensive ion charging current is presented for the first time based on the orbit motion limited (OML) approach. The variable dust charge is then expressed in terms of the Lambert function and...

The correct nonextensive electron and ion charging currents are presented for the first time based on the orbit motion limited approach. For −1<q<1, where q measures the amount of plasma nonextensivity, the nonextensive electron charging current is expressed in terms of the hypergeometric function. The variable dust charge is expressed in terms of...

Nonlinear dust-acoustic (DA) shock waves are addressed in a nonextensive dusty plasma exhibiting self-consistent nonadiabatic charge variation. Our results reveal that the amplitude, strength and nature of the DA shock waves are extremely sensitive to the degree of ion nonextensivity. Significant differences in the potential function occur for very...

A first theoretical work is presented to study variable charge dust acoustic solitons within the theoretical framework of the Tsallis statistical mechanics. Our results reveal that the spatial patterns of the variable charge solitary wave are significantly modified by electron nonextensive effects. In particular, it may be noted that for −1<q<1 (wh...

Arbitrary amplitude ion-acoustic solitary waves are addressed in a two-component plasma with a q-nonextensive electron velocity distribution. Our results show that in such a plasma solitary waves, the amplitude and nature of which depend sensitively on the q-nonextensive parameter can exist. Due to the electron nonextensivity, our plasma model can...

A semi-analytic model for highly nonlinear solitary waves involving dust phase-space vortices (holes) is outlined. The variable dust charge is expressed in terms of the Lambert function and we take advantage of this transcendental function to investigate the localized structures that may occur in a dusty plasma with variable charge trapped dust par...

The problem of nonlinear positron acoustic solitary waves involving the dynamics of mobile cold positrons is addressed. A theoretical work is presented to show their existence and possible realization in a simple four-component plasma model. The results should be useful for the understanding of the localized structures that may occur in space and l...

A first theoretical attempt is made to investigate small amplitude, variable charge dust Bernstein–Greene–Kruskal (BGK) double layers (DLs). The nature of the dust BGK-DLs (compressive or rarefactive), their strength and thickness depend sensitively on the net negative charge residing on the grain surface, the dust grain dynamics and, more interest...

Arbitrary amplitude dust acoustic waves in a high energy-tail ion distribution are investigated. The effects of charge variation and ion suprathermality on the large amplitude dust acoustic (DA) soliton are then considered. The correct suprathermal ion charging current is rederived based on the orbit motion limited approach. In the adiabatic case,...

A numerical investigation is presented to show the existence, formation, and possible realization of large-amplitude dust acoustic (DA) solitary waves in a charge varying dusty plasma with nonthermal ions. These nonlinear localized structures are self-consistent solutions of the collisionless Vlasov equation with a population of fast particles. The...