Ion-acoustic Solitary Waves Research Articles

Dust Ion Acoustic Solitary Waves in Multi-Ion Dusty Plasma System

A theoretical work has done to observe the existence of dust ion-acoustic (DIA) solitary waves (SWs) in a multi-ion dusty plasma system consisting of inertial positive and negative ions, Maxwell’s electrons, and arbitrary charged stationary dust. In this short communication, our research declares that with these components the derivation of Korteweg-de Vries (K-dV) and mixed K-dV (mK-dV) is possible. Here reductive perturbation method has been employed in all these approaches. The first K-dV equation has been derived which gave both bright and dark solitons but for a very limited region. Then the mK-dV equation has been derived that gave bright soliton for a large region, but no dark soliton has been observed.

Obliquely propagating ion-acoustic solitary and shock waves in magnetized quantum degenerate multi-ions plasma in the presence of trapped electrons

The properties of obliquely propagating ion-acoustic waves have been investigated in multi-ions magnetized plasma comprising of inertial, positively and negatively charged ion fluids, trapped electrons, and negatively charged stationary heavy ions. The propagation of the waves is oblique to the ambient magnetic field which is along the z-direction. Only fast type of modes exists in the linear regime. The reductive perturbation method was adopted to derive the Korteweg– de Vries (KdV) and Burger equations, as well as the solitary and shock wave solutions of the evolved equations, have been used to analyze the properties of the small but finite amplitude waves. The effects of the constituent plasma parameters, namely, the trapping effect of electrons, the electron degenerate temperature and the viscosity coefficient on the dynamics of the small amplitude solitary and shock waves have been examined. The influence of the magnetic field and the obliquity parameter on the propagation characteristics of ion-acoustic waves are discussed.

Propagation of dust ion acoustic solitary waves in dusty plasma with Boltzmann electrons

In this multispecies plasma model, consisting of negative mobile dusts, non-thermal ions and Boltzmann electrons, dust-ion acoustic solitary waves are studied through reductive perturbative technique by deriving corresponding Korteweg-de Vries (KdV) equation. The number of dust charge contained in a dust particle (Zd) and the streaming speeds of mobile dusts (ud0) and ions (ui0) are observed to play very important role to form dust-ion acoustic compressive and rarefactive KdV solitons. Remarkably, some initial streaming of dust (ud0) are found to be instrumental for both compressive and rarefactive KdV solitons in a short range of Zd separating both kinds by some asymptotic lines. Also, the presence of low dust charges and lower ion streaming, compressive and rarefactive KdV solitons of either concave or convex characters are shown to reflect. For the higher streaming of mobile dusts, the amplitudes of the rarefactive KdV solitons characteristically changes from higher to lower showing convex character for this plasma model. A rigorous theoretical investigation has been made to show how the number of dust charge contained in a dust particle (Zd) drastically change the amplitudes of the compressive and rarefactive KdV solitons.

Evolution of dust ion acoustic soliton in the presence of superthermal electrons

Propagation of solitary wave in dusty plasmas started to draw the attention of the physicists since the early 90s. The presence of superthermal particles seems to have a great impact on such waves, as they indicate the existence of non-thermal systems. It has been observed that the superthermal population is capable of altering the nature of the plasmas waves. In the present paper, the effect of the superthermal electron population on the dust ion acoustic solitary wave has been explored. The plasma is considered un-magnetized and composed of two components of superthermal electrons (of two distinct temperature) along with positive ions, and negative dust particles. A major part of the work has been concentrated on the stability of the solitary structures considering the effect of the superthermal parameter. In addition, the dust charge has been considered as a variable and a detailed analysis has been provided on the same. The proposed plasma model is most suitable for analyzing Saturn magnetosphere and can be extended to any space plasmas with superthermal population.

Head-on Collision of Ion-Acoustic Solitary Waves with Two Negative Ion Species in Electron–Positron–Ion Plasmas and Production of Rogue Waves

The interactions between ion acoustic solitary waves (IASWs) are investigated considering completely ionized electron–positron–ion (e–p–i) plasmas consisting of ions with positive and two negative species, nonthermal electrons, and positrons. Two-sided Korteweg–de Vries (KdV) and modified KdV (mKdV) equations are derived using extended Poincare–Lighthill–Kuo (ePLK) reductive perturbation method. To investigate the production of ion-acoustic rogue waves (IARWs), the rational solution of nonlinear Schrodinger equation (NLSE) is derived from the mKdV equation. Two types of plasmas containing $${\text{A}}{{{\text{r}}}^{ + }}$$ , $${{{\text{F}}}^{ - }}$$ , and $${\text{SF}}_{{\text{5}}}^{ - }$$ species, as well as $${\text{SF}}_{{\text{5}}}^{ + }$$ , $${{{\text{F}}}^{ - }}$$ , and $${\text{SF}}_{{\text{5}}}^{ - }$$ species, are taken into account to study their effects on the amplitudes and phase shifts after collision, as well as the production and properties of rogue waves (RWs). It is observed during collision that a high-amplitude wave is produced in the interaction region depending on the type and parameters of plasmas. The nonthermality of electrons and positrons, electron-to-positron temperature ratio, and the density of negative ions modify the phase shift and amplitude of the waves produced during the collision of the two solitons. The amplitude of the RW for the $${\text{A}}{{{\text{r}}}^{ + }}$$ , $${{{\text{F}}}^{ - }}$$ , and $${\text{SF}}_{{\text{5}}}^{ - }$$ plasmas is found to be larger than that for the $${\text{SF}}_{{\text{5}}}^{ + }$$ , $${{{\text{F}}}^{ - }}$$ , and $${\text{SF}}_{{\text{5}}}^{ - }$$ plasmas.

Dust Acoustic Solitary Waves in a Five Component Plasma-Application to Comets

We have studied the characteristics of the Dust Acoustic Solitary Wave (DASW) in a five component cometary plasma composed of two components of electrons (one hotter and one colder), hydrogen ions and a pair of oppositely charged dust particles (heavier ions). The Korteweg – deVries wave equation has been derived for the system and its solitary wave solution obtained. The dust acoustic solitary wave amplitude is almost a constant with varying temperatures of the hot electron component but decreases with increasing hydrogen ion densities. A comparison with a complementary nonlinear wave, the Dust Ion Acoustic Solitary Wave, has also been made. Keywords: Dust acoustic solitary wave, K dV equation, kappa distributed ions and electrons Cite this Article Neethu Theresa Willington, Sijo Sebastian, Chandu Venugopal. Dust Acoustic Solitary Waves in a Five Component Plasma-Application to Comets. Research & Reviews: Journal of Physics . 2019; 8(2): 44–51p.

Classification of head-on collisions of ion-acoustic solitary waves in a plasma consisting of cold ions and Boltzmann electrons

Head-on collisions of ion-acoustic solitary waves in a collisionless plasma consisting of cold ions and Boltzmann electrons are studied using the particle-in-cell simulation. It is shown that the collision of solitary waves can occur under different scenarios. Solitary waves preserve or do not preserve their amplitudes and shapes after a collision, depending on their initial amplitudes. The range of initial amplitudes, at which a solitary wave preserves its identity after collisions, is established. The use of a diagram of initial amplitudes of colliding solitary waves to consider possible collision scenarios is discussed. The characteristic regions in the diagram of the initial amplitudes corresponding to different collision scenarios are determined, and a classification of head-on collisions of ion-acoustic solitary waves in a plasma is proposed.

Interaction phenomena of ion acoustic solitary waves with singly charged cold ions and Boltzmann electrons

The linear features and phenomena concerning head-on collision between the two ion acoustic solitary waves are investigated considering the multi-component plasma system comprising singly charged cold positive and negative ions, and Boltzmann electrons. Linear characteristics of ion acoustic solitary waves are studied taking the dispersion relation into account. The two-sided Korteweg-de Vries (KdV) equations are derived to investigate the structures of the solitons and the phase shift of ion acoustic solitary waves due to collisions by the extended Poincaré-Lighthill-Kuo (ePLK) method. The linear analyses reveal that the densities of the ionic species and wave number modify the ion acoustic solitary wave frequency, and higher density of electrons changes the group velocity. It is found that a new wave is produced with high amplitude in the interaction region due to head-on collision between the waves. The compressive and rarefactive KdV solitons are produced due to the changes of density. The density ratios such as and modify the phase shift and nonlinear phase velocity after head-on collision.

On a semiclassical model for ion-acoustic solitons in ultrarelativistic pair plasmas and its classical counterpart

Large ion-acoustic solitary waves are investigated in a multispecies plasma model consisting of warm positive ions in the presence of ultrarelativistic electrons and positrons, in a Sagdeev pseudopotential formalism. A parametric investigation determines existence regions in terms of fractional densities, temperature ratios, and soliton speeds. Various examples of pseudopotential functional forms, as well as those of the resulting soliton and electric field profiles, can then be generated numerically, and some typical illustrations have been included. Rather than adiabatic pressure-density relations for the hot species, the classical nonrelativistic counterpart involves Boltzmann distributions, which differ qualitatively from the literature. Surprisingly, the soliton and electric field profiles show scant differences at the same compositional parameters between the two extremes even though the physical description of the hot species is radically different. A brief comparison has also been included between the fully nonlinear Sagdeev pseudopotential descriptions and their respective associated weak-amplitude limits (treated via a reductive perturbation technique) in which nonlinearities have been truncated to low powers of the electrostatic potential. Again, the soliton profiles are not radically different at comparable amplitudes, leaving the underlying physical reasons for such a similarity an open problem.

Role of ion thermal velocity in the formation and dynamics of electrostatic solitary waves in plasmas

We perform fluid simulations to examine the effect of ion thermal velocity on the formation and dynamics of solitary waves in an unmagnetized two-component plasma consisting of ions and electrons. Based on the linear and nonlinear fluid theories, some of the previous studies have reported that the plasma with the electron temperature greater than the ion temperature (i.e., Te > Ti) supports ion acoustic solitary waves (IASWs), whereas the plasma with Te ≪ Ti supports electron acoustic waves (EASWs). In this paper, we have considered a wide range of ion temperatures (with fixed electron temperature) to examine the criteria of temperature and thermal velocities in the generation of EASWs and IASWs in plasmas. Our simulation shows that the plasma with Ti > Te possesses two wave modes depending on the ratio of its thermal velocities. When the ratio of electron to ion thermal velocities R = Vthe/Vthi > 1, the system supports the generation of IASWs, whereas for R < 1, it supports the generation of EASWs. The analysis of characteristics like the amplitude, width, and phase speed of these solitary waves implies that the EASWs have a negative potential, whereas the IASWs have the positive potential. The transition from IASWs to EASWs occurs when the phase speed of the solitary wave exceeds the limiting value of 3Vthe. This simulation study presents the detailed investigation of the evolution of EASWs and IASWs generated in plasmas having Ti > Te, which will have implications in modeling such waves in space and laboratory plasmas.

Obliquely propagating nonlinear ion-acoustic solitary and cnoidal waves in nonrelativistic magnetized pair-ion plasma with superthermal electrons

The nonlinear propagation of ion-acoustic waves is considered in a magnetized system of collisionless and dissipative pair-ion plasma, composed of cold positively and negatively charged nonrelativistic ions, with superthermal electrons. obliquely propagating ion-acoustic solitary and cnoidal waves are investigated via a mechanical-motion analog Korteweg de Vries (KdV) approach. The characteristics of the emerged nonlinear magnetized waves are significantly modified by the effects of plasma parameters like the obliquity angle, superthermality parameter, negative to positive ions density ratio, electron density and it is also affected by the electron temperature. The obtained results can be generalized to be used to investigate the plasma waves nature in neutron stars, Saturn’s and Pulsars magnetospheres in addition to the laboratory plasmas.

Some new families of solitary wave solutions of the generalized Schamel equation and their applications in plasma physics

In this article we studied analytically the propagation of nonlinear ion acoustic solitary waves modeled by the generalized Schamel (GS) equation arising in plasma physics using auxiliary equation mapping method. As a result, we found a series of more general and new families of solutions, which are more powerful in the development of soliton dynamics, quantum plasma, adiabatic parameter dynamics, biomedical problems, fluid dynamics, industrial studies and many other fields. The calculations prove that this method is more reliable, straightforward, and effective to study analytically other nonlinear complicated physical problems modeled by complex nonlinear partial differential equations arising in mathematical physics, hydrodynamics, fluid mechanics, mathematical biology, plasma physics, engineering disciplines, chemistry and many other natural sciences. We also have expressed our solutions graphically with the help of Mathematica 10.4 to understand physically the behavior of different shapes of ion acoustic solitary waves including kink-type, anti-kink-type, half-bright and dark soliton.

Acceleration and Trapping of Ions upon Collision of Ion-Acoustic Solitary Waves in Plasma with Negative Ions

The phenomena occurring under head-on collision of ion-acoustic solitary waves in collisionless plasma consisting of positive and negative ions and electrons obeying the Boltzmann distribution are considered. Using particle-in-cell simulations, it is shown that large-amplitude compressive ion-acoustic solitary waves do not preserve their identity after the collision. Their amplitudes decrease and their shapes change. It is shown that the collision is accompanied by the generation of fast positive ions the velocity of which can exceed more than threefold the speed of sound. In addition, the collision is accompanied by the trapping of negative ions by the field of ion-acoustic solitary waves formed after the collision.

Scattering of electron holes in the context of ion-acoustic regime

Mutual collisions between ion-acoustic solitary waves are studied based on a fully kinetic simulation approach. Two cases, small and large relative velocities, are studied, and the effect of trappe ...

Analytical solutions of cylindrical and spherical dust ion-acoustic solitary waves

Abstract In the present work, employing the conventional reductive perturbation method to the field equations of an unmagnetized dusty plasma consisting of inertial ions, Boltzmann electrons and stationary dust particles in the nonplanar geometry we derived cylindrical(spherical) KdV and mKdV equations. Being aware of the fact that there exists no exact analytical solution for the progressive waves for such evolution equations we presented the exact analytical solution of a generalized form of such evolution equations in the planar geometry and used this solution to obtain an analytical approximate progressive wave solution to the generalized evolution equation. Then the progressive wave solutions for the cylindrical(spherical) KdV and m-KdV equations is obtained as some special cases. The analytical approximate solutions so obtained are compared with the numerical solutions of these equations. The results reveal that both solutions are in a good agreement. One advantage of present analytical approximate solution is that it allows readers to gain information, share understandings, or carry out a physical parametric study on the evolution solution behavior as well as the solution calculation has no CPU time-consuming or round off error.

Head-on Collision of Ion-Acoustic Shock and Solitary Waves in Collisionless Plasma with Pair Ions and Electrons

Unmagnetized collisionless plasma system consisting of positive- and negative ions, and electrons are considered to study the head-on collision of ion-acoustic shock waves (IASWs) and its effects on the formation of shock (monotonic and oscillatory) waves and phase shift. The soliton solution is derived from the two-sided Korteweg-de Vries Burger (KdVB) equations. The KdVB equations are obtained using extend Poincare-Lighthill-Kuo (ePLK) method. It is assumed that the negative ions are immobile and the electrons follow the Boltzmann energy distribution in the plasma. The effects of plasma parameters such as density ratios and kinematic viscosities on electrostatic shock profiles, phase shift, amplitudes, formation of shock (monotonic and oscillatory) as well as on the soliton solution are investigated. It is found that the density ratio of negative to positive ions plays a vital role on the formation of shock waves and phase shift after collision.

Ion-Acoustic Solitary Wave Solutions of Three-Dimensional Zakharov-KuznetsovBurgers Equation for Dust Ion Acoustic Waves and Their Applications

Modified extended mapping method is further modified to discover traveling wave solutions of non- linear complex physical models, arising in various fields of applied sciences. The method is applied to three-dimensional ZakharovKuznetsov-Burgers equation in magnetized dusty plasma. Consequently different kinds of families of exact traveling wave solutions that represent electric field potential, electric and magnetic fields are fruitfully surveyed, with the help of Mathematica. The obtained novel exact traveling wave solutions are in different forms such as bright and dark solitary wave, periodic solitary wave, dark and bright soliton, etc., that are represented in the forms of trigonometric, hyperbolic, exponential and rational functions. The properties of some of the novel traveling wave solutions are shown by figures. The obtained results exhibit the effectiveness, power and exactness of the method that can be used for many other nonlinear problems.

Effects of positive ion temperature and negative ion number density on arbitrary amplitude ion-acoustic solitary waves in nonextensive electronegative plasma

The formation and the basic features of arbitrary amplitude ion-acoustic solitary waves (IASWs) in an electronegative plasma containing cold negative ion fluid, warm positive ion fluid and nonextensive electrons are theoretically investigated by using the pseudo-potential technique. The pseudo-potential is analytically and numerically analyzed and the conditions for the formation of the arbitrary amplitude IASWs and their basic features (viz. polarity, amplitude, width etc.) are identified. It is observed that the electronegative plasma under consideration supports the coexistence of compressive and rarefactive IASWs, and that the temperatures and number density of positive ion fluid significantly modify not only the basic features of compressive and rarefactive IASWs, but also the parametric regime of their coexistence. The implications of our results in some space and laboratory electronegative plasma situations are finally pinpointed.

Oblique propagation of ion-acoustic solitary waves in a magnetized plasma with electrons following a generalized distribution function

A magnetized plasma containing inertial ions and non-inertial electrons following a generalized distribution function, which reduces to Maxwellian, κ type superthermal, and trapped distribution functions for different limiting cases, is considered. The reductive perturbation method is employed to examine the formation and basic features of small but finite amplitude obliquely propagating ion-acoustic solitary waves (OPIASWs) in such a magnetized plasma. The effects of the parameters involving superthermal and trapped distribution functions, obliqueness, and external magnetic field on the basic features of OPIASWs are identified. The applications of the results of this work in different space and laboratory plasma situations are briefly discussed.

Damped electrostatic ion acoustic solitary wave structures in quantum plasmas with Bohm potential and spin effects

Nonlinear properties of ion acoustic solitary waves are studied in the case of dense magnetized plasmas. The degenerate electrons with relative density effects from their spin states in the same direction and from equally probable up and down spinning states are taken up separately. Quantum statistical as well as quantum tunneling effects for both types of electrons are taken. The ions have large inertia and are considered classically, whereas the electrons are degenerate. The collisions of ions and electrons with neutral atoms are considered. We derive the deformed Korteweg de–Vries (DKdV) equation for small amplitude electrostatic potential disturbances by employing the reductive perturbation technique. The Runge–Kutta method is applied to solve numerically the DKdV equation. The analytical solution of DKdV is also presented with time dependence. We discuss the profiles for velocity, amplitude, and time variations in solitons for the cases when all the electrons are spinning in the same direction and for the case when there is equal probability of electrons having spin up and spin down. We have found that the wave is unstable because of the collisions between neutral gas molecules and the charged plasmas particles in the presence of degenerate electrons.