Contributions to Plasma Physics最新文献

In this work, we investigate the exact travelling wave solutions of the space–time fractional (3 + 1)-dimensional Korteweg–de Vries–Calogero–Bogoyavlenskii–Schiff (KdV-CBS) equation and the negative-order (3 + 1)-dimensional KdV-CBS equation (nKdV-nCBS) by utilizing Sub equation method (SEM). The fractional partial differential equations (FPDEs) are transformed to nonlinear ordinary differential equations (ODEs) by using a suitable traveling wave transformation. Numerous soliton-type solutions, such as kink, anti-kink, singular, singular periodic, and multi-soliton singular wave forms, are generated using the suggested approach. Both two and three-dimensional graphical representations are used for understanding the behavior of these acquired solutions followed by physical significance. The obtained solutions are indeed beneficial for analyzing the wave propagation in complex media like nonlinear optics, hydrodynamics, plasmas, and fluid systems. The SEM provides a simple, effective, and efficient method for solving high-dimensional nonlinear FPDEs in contrast to other approaches in the literature. The results presented in this work not only enrich the family of exact solutions for fractional KdV-type models but also demonstrate the effectiveness of the conformable derivative framework in capturing complex nonlinear wave dynamics relevant to mathematical physics.

Using a non-relativistic warm fluid model, the wave-breaking limit of upper-hybrid waves (UHWs) in magnetized plasmas is derived. This limit—termed “Coffey limit” in magnetized plasmas—is found to decrease with the increase of an ambient magnetic field. A nonlinear dispersion relation for UHWs is also derived, showing its considerable dependency on wave amplitude. These results will be of relevance to laboratory applications of wave-breaking involving magnetic fields.

The study gives a detailed theoretical framework for ion temperature gradient (ITG) modes in magnetized, inhomogeneous electron-ion plasmas, where electron behavior is taken as a Kaniadakis distribution. The fluid description is extended under electrostatic, low-frequency drift ordering, allowing for a systematic analysis of both linear and nonlinear regimes. Non-Maxwellian electrons influence ITG growth rates and spectral characteristics. While in the nonlinear regime we obtained the Korteweg-de-Vries and Burger equations with modified nonlinear, dispersion, and dissipation coefficients that depend on the different plasma parameters as well as on the spectral index of the distribution. These findings can be applicable to the space as well as to the laboratory plasmas.

The nonlinear propagation characteristics of dust-ion-acoustic shock waves are investigated in a magnetized viscous dusty plasma with the effect of dust charge fluctuation, the (r, q) distributed electrons, and the anisotropic ion pressure. By employing the standard reductive perturbation method and the Tanh method, we derive the nonlinear Korteweg–de Vries Burgers (KdVB) equation and its solution. By numerical analysis, we show the effect of spectral indices r and q on the dust-ion-acoustic shock waves potential Φ and associated magnitude of electric field E. Besides, we find that the impact of external magnetic field Ω, obliqueness l_z, the ion kinematic viscosity η₀, anisotropic ion pressure p₁ and p₂, density ratio of electron to ion μ and dust grain radius r_d can significantly modify the characteristics of the shock waves. These results may be useful for better understanding the nonlinear propagation of shock structures in space and laboratory plasma with non-Maxwellian distributed electrons.

We reexamined the variation of the dust grain charge in a dusty plasma within the framework of the Double Spectral Distribution (DSD). Using the Orbital Motion Limited (OML) approach, the exact expression for the generalized electron current corresponding to the $���\left(��r�,�q��\right)��$ distribution was derived. The impact of this distribution on the equilibrium charge of the dust grain was thoroughly investigated. The results reveal that the $���\left(��r�,�q��\right)��$ distribution significantly alters the electron current, and consequently, the equilibrium grain charge. The effects of the two parameters $��r�$ and $��q�$ are similar in that they both contribute to making the grain charge less negative, a behavior analogous to that observed by Tribeche and Shukla in the context of the nonextensive Tsallis distribution.

This paper presents propagation dynamics of dark hollow Gaussian (DHG) laser beams in cold quantum plasma (CQP). The nonlinear differential equation describing the evolution of width of the beam with propagation distance is obtained based on the Wentzel-Kramers-Brillouin (WKB) and paraxial-like approximations by taking into account the dielectric function of CQP. An influence of higher ordered DHG beams on the nature of self-focusing in CQP is specifically examined. Numerical results are compared with classical relativistic (CR) plasma. Weakening of self-focusing in CQP is observed for higher-order DHG beams. Additionally, an enhanced self-focusing of DHG beams is observed in CQP as compared with CR case of reference.

A theoretical investigation is performed to examine the properties of dust-acoustic shock waves on a dissipative unmagnetized dusty plasma consisting of negatively charged dust, Maxwellian ions, and non-extensive $��q�$-distributed electrons. By employing the reductive perturbation method, the damped Korteweg–de Vries–Burgers (KdVB) equation for a plasma system under consideration is derived. The properties (phase speed, amplitude, width, etc.) of the shock waves are influenced by the plasma parameters, including dissipative forces (viscosity via $��\eta �$ and collisions via $��\nu �$), mass of dust grains, number density of dust grains, dust charge state, nonextensivity (via $��q�$) and dust temperature. The results offer significant implications and importance in both space and laboratory plasmas.