Contributions to Plasma Physics最新文献

This research examines the correlation between temperature effects and surface charging problems on a silicon dioxide mask using simulation techniques. The findings of this study validate the significance of considering electron–solid interactions, especially when influenced by varying temperatures. The impacts of temperature changes on the spatial distributions of net charge deposition, electric potential, and electric field are examined. It was noted that the temperature rise leads to an increase in the concentration of positively charged holes near the surface of the mask, thereby diminishing the spatial dispersion of positive potential. This results in a less conspicuous alteration of the mask profile as the temperature increases. This investigation is anticipated to possess substantial significance and offer valuable insights for optimizing mask design.

The interplay of dust acoustic waves (DAWs) and it's amplitude modulation is investigated in a magnetized five-component cometary plasma comprising positively charged hydrogen and oxygen ions, negatively charged dust grains, along with superthermal electrons (solar and cometary). The interplay dynamics of the dust acoustic waves (DAWs) is described by the Kortweg–de Vries (KdV) equation. The appearance of multi-soliton profiles are derived using Hirota's method. The amplitude modulation of the DAWs is investigated through nonlinear Schrodinger equation. In the numerical study, it appears that the dark-envelope soliton may exist in such cometary plasmas, but the emergence of bright-envelope soliton is not possible at any condition. Superthermality, magnetic field strength, ion and electron concentration, and other physical factors have all been explored for their impacts. The findings of this research may contribute to our understanding of the nonlinear characteristics and wave propagation stability of electrostatic wave excitations in cometary coma environments.

We consider a two-component asymmetric complex plasma of finite-size macroions with charges $��Z�$ ($��Z�\gg �1�$) and point oppositely charged microions with unit charges. System pressure is calculated within the framework of the Poisson–Boltzmann plus hole approximation by obtaining the Coulomb nonideal parts of interaction energy and Helmholtz free energy. It is shown that both the pressure and plasma isothermal compressibility are positive over the entire range of macroion concentrations. We compared pressure and isothermal compressibility in linearized approximations and in the Poisson–Boltzmann plus hole approximation where the nonlinear screening effect is taken into account and showed a significant difference for some macroions concentrations.

The fundamental characteristics of ion-acoustic waves (IAWs) due to the relativistic effects are investigated in a collisionless unmagnetized plasma system consisting of relativistic positively charged inertial heavy ions, kappa-distributed electrons, and Maxwellian light ions. The reductive perturbation method (RPM) is used to derive the nonlinear evolution equation like the Korteweg-de Vries (KdV) equation. The production of single-, double-, and triple-IAW solitons (IAWSs) is also investigated. It is found that for the effects of concerned parameters only rarefactive (IAWSs) are produced. The results obtained in this study are useful not only to understand the space plasma phenomena such as plasma sheet boundary layer of earth's magnetosphere, laser-plasma interaction, but also to validate the laboratory experiments.

A time-dependent nonlinear model that describes the generation of vortex patterns of dust grains in a magnetized strongly coupled dusty plasma where ions are taken magnetized [Nebbat and Annou, Phys. Plasmas 30 (8), 082108 (2023)] is augmented. The effect of viscosity and dust charge variation on the characteristics of the vortex is investigated.

The nonlinear structure and dynamics of dispersive solitons and breather waves described by Korteweg-de Vries and nonlinear Schrödinger equations are studied. The theoretical and numerical study of the generalized hydrodynamic equations, accounting for wave dissipation and particle production-loss mechanism, are considered. The reductive expansion method has been used in the context of the instability problem of multi-fluid dynamics, applied to the study of electrostatic solitons and ion-acoustic waves. A nonlocal model of interacting solitary-breather waves has been presented. Applications of the theory, concerning the ion streaming instability in the framework of plasma physics, are presented.

The present study investigates the interaction between a proton-electron plasma beam and an arched magnetic trap using the particle-in-cell (PIC) simulation method. The results show that when the magnetic field is sufficiently weak, the beam disrupts the arched magnetic field configuration, causing the breaking and reconnection of magnetic field lines. The relationships between the coil current threshold (the coil current at which the disruption of the magnetic induction just happens) and initial plasma velocity, and between the critical beam velocity (the plasma is just enough to reach the arched magnetic field) and coil current, are quantified. Additionally, the interaction between the beam and the arched magnetic field is observed to induce microwave excitation. These findings lay the foundation for theoretically simulating the dynamic behavior of space plasma in a unique magnetic field environment within a laboratory setting.