Nonlinear dynamics in the Jupiter magnetosphere: implications of dust-acoustic cnoidal mode

Different types of waves and their nature in the Jovian middle magnetosphere are still not clear or specified. For this purpose, a generalized hydrodynamic model for an arbitrary amplitude dust-acoustic waves is built for true Jovian magnetosphere. The plasma system consists of positive dust grains, Maxwellian ions and electrons. An evolution equation containing a Sagdeev potential is derived, and its numerical analysis is presented. Unexpectedly, the given data yielded cnoidal waves only with positive potential. The effect of the external magnetic field, Mach number, and directional cosine parameters are studied and manipulated. We think that the present results are important in realizing the main waves in the Jovian magnetosphere, and the possible correlation to its particlesístability and pole acoustic waves.

Electron-Acoustic (Un)Modulated Structures in a Plasma Having (r, q)-Distributed Electrons: Solitons, Super Rogue Waves, and Breathers

The propagation of electron-acoustic waves (EAWs) in an unmagnetized plasma, comprising (r,q)-distributed hot electrons, cold inertial electrons, and stationary positive ions, is investigated. Both the unmodulated and modulated EAWs, such as solitary waves, rogue waves (RWs), and breathers are discussed. The Sagdeev potential approach is employed to determine the existence domain of electron acoustic solitary structures and study the perfectly symmetric planar nonlinear unmodulated structures. Moreover, the nonlinear Schrödinger equation (NLSE) is derived and its modulated solutions, including first order RWs (Peregrine soliton), higher-order RWs (super RWs), and breathers (Akhmediev breathers and Kuznetsov–Ma soliton) are presented. The effects of plasma parameters and, in particular, the effects of spectral indices r and q, of distribution functions on the characteristics of both unmodulated and modulated EAWs, are examined in detail. In a limited cases, the (r,q) distribution is compared with Maxwellian and kappa distributions. The present investigation may be beneficial to comprehend and predict the modulated and unmodulated electron acoustic structures in laboratory and space plasmas.

Multi-component dense plasma with ion and super-thermal electrons with kappa distribution

The soliton waves are one of the nonlinear phenomena which can propagate in the different types of plasma such as multiple particles of plasma, nonthermal plasma, and space plasma. Using the Sagdeev potential technique, the stability conditions of the soliton waves in the nonthermal plasma have been theoretically studied. One of the significant factors that can affect the propagation of the soliton waves is the distribution function such as nonMaxwellian distribution function or Kappa distribution function. In this paper, we try to investigate the soliton wave in the unmagnetized multi-component plasma consisting of the nonthermal electron and the nonthermal ion, positron and dust with Kappa distribution function. Then by using the Sagdeev potential, the nonlinear equation for the potential is obtained and then the compression and rarefaction soliton waves are computed with the numerical method for this nonlinear wave. Finally, by imposing the Sagdeev potential condition, we discuss the stability of these soliton waves.

Effect of Nonthermal Ions on Dust Acoustic Waves in Magnetized Plasma

A fluid model is considered to study the nonlinear dust- acoustic waves (DAW) in magnetized dusty plasma. The model consists of dust articles having negative charge, nonthermal ions, and Boltzmann electrons. Sagdeev Potential equation is derived in the form of an energy integral by applying nonperturbative approach. The pseudopotential (Sagdeev potential) profile is analyzed to study the characteristic of the solitary waves. The study has been made related to the transition of the DAW and the corresponding characters by observing the variation of amplitudes and width of the solitons with Mach number, temperature ratio, density ratio, concentration of nonthermal ions, and the direction cosine. The parametric ranges are estimated numerically to confirm the existence of solitary waves of arbitrary amplitude.

Collapsible and Spiky Wave for Dust Acoustic Waves in Dusty Plasmas

In multicomponent dusty plasma, the Sagdeev Potential (SP) approach is employed to formulate the Energy Equation for arbitrary amplitude dust acoustic waves (DAWs), where an amount of electrons is trapped in potential well. The dependence of amplitude and width of the solitons of Sagdeev Potential on plasma parameters is widely discussed. The range of Mach number has determined for solitary waves (SWs) with the help of critical Mach number. The solution of the Energy Equation obtained, has been discussed by expanding the expression for SP in the higher terms of φ . The different solutions of Energy Equation give us SWs, breakable waves, collapsible waves and SWs with spiky and explosive nature. The role of temperature ratio on the transformation of SWs to collapsible waves is discussed. With the help of standard values of plasma parameters relevant to such plasma environment, the results so obtained, are discussed. These results may help us to explain the nature of SWs in different astrophysical situations.

Small-amplitude supersolitons near supercritical plasma compositions

Supercritical plasma compositions in parameter space are considered for a general fluid model consisting of an arbitrary number of species. This is done by applying a Taylor series expansion of the Sagdeev potential about the acoustic speed and the equilibrium electrostatic potential. A novel finding in this study is the description of small-amplitude supersolitons. Our analysis allows us to determine the plasma compositional criteria for such structures, as well as lower and upper bounds of their velocities and amplitudes. We therefore establish an interesting link between supercritical plasma compositions and the existence of supersolitons. The results are illustrated via a case study where plasmas consisting of cold ions and two Boltzmann electron species are considered.