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The effect of ion temperature, magnitude of magnetic field and its orientation on a magnetized plasma sheath consisting of electrons and two species of positive ions are investigated. Using three-fluid hydrodynamic model and some dimensionless variables, the dimensionless equations are obtained and solved numerically. It is found that with the increase of the ion temperature and magnetic field strength there is a significant change in ion densities and energies in the sheath. It is also noticed that increase of magnetic field angle enhances the ion density near the sheath edge for a constant ion temperature. With increase in ion temperature and magnetic field angle, the lighter ion density near the sheath edge enhances and reverses for the heavier ion species. [ABSTRACT FROM AUTHOR]

In a magnetized plasma with a temperature anisotropy T||>T⊥ (where || and ⊥ denote directions with respect to the uniform magnetic field B0), the nonresonant Weibel instability can develop and destabilize purely growing, ordinary plasma modes (k=k⊥). This paper presents a rigorous extended analysis of this instability on the basis of a new threshold b0(k), which enables to determine the instability conditions as well as the upper limits of the growth rates. Accurate analytical forms of the threshold conditions are provided here for the first time and for the full physical range of the temperature anisotropy and the parallel plasma beta. The marginal and threshold conditions for the plasma parameters, which directly lead to an instability of the ordinary mode, are explicitly derived numerically and analytically. The new analytical tools developed here provide premises for a comprehensive investigation of the interplay of this instability with the firehose instability, as they both can develop in the same conditions. [ABSTRACT FROM AUTHOR]

This paper investigates the filamentation instability of a non-relativistic electron beam passing through a periodic longitudinal magnetic field and an infinite uniform magnetized plasma. The linearized fluid-Maxwell equations are used to derive an equation for the dispersion relation of quantum magnetized plasma. The resulting dispersion equation is analyzed numerically over a wide range of system parameters. It is found that the growth rate of the filamentation instabilities is strongly affected by the strength of the periodic magnetic field. [ABSTRACT FROM AUTHOR]

A possibility of relaxation of an electronegative dusty plasma composed of two flowing ion species with stationary dust particles is explored. It is shown that magnetic field in such a system has the potential to self-organize giving rise to multiple Beltrami fields. When all the inertial and noninertial forces are taken into account, the relaxed state comes out to be a triple curl Beltrami field. On ignoring the inertia of lighter ions relative to heavy ones, double curl Beltrami field appears as a relaxed state which is equivalent to the superposition of two Beltrami fields. It shows the importance of inertia of plasma components in the formation of relaxed magnetic field structures. It is also shown numerically that scale separation allows the simultaneous existence of magnetic field and velocities varying at vastly different length scales. This gives rise to a dynamo mechanism at relaxed equilibrium. The study bears a strong relevance to the formation of multi scale structures in electronegative dusty plasmas, found in space and laboratory. [ABSTRACT FROM AUTHOR]

A theory of wiggler pumped ion-channel free-electron laser (WPIC-FEL) and an axial magnetic field is presented. The motion of a relativistic electron is analyzed in the field configuration consisting of a helical wiggler magnetic field, a uniform axial magnetic field, and an electrostatic electric field produced by an ion-channel. An equation for the function [uppercase_phi_synonym], which determines the rate of change of axial velocity with energy, is derived. Numerical calculations are made to illustrate the effects of two electron beam guiding devices on the trajectories. By means of linear fluid theory, the sixth-degree polynomial dispersion equation for electromagnetic and space-charge waves is derived. The dependence of growth rate-frequency curves on the ion-channel frequency and axial magnetic field is studied numerically. [ABSTRACT FROM AUTHOR]

The effects of quantum statistic and quantum diffraction on the weakly two-dimensional fast quantum dusty magnetosonic wave propagating perpendicular to the external magnetic field are investigated by considering the inertialess electron, inertialess ion, and inertial cold dust in the low frequency limit. A Kadomstev-Petviashvili equation is derived for the magnetosonic solitary wave by using reductive perturbation method. The results show that the amplitude of soliton increases with the increasing of quantum diffraction effects of both electrons and ions, while the amplitude of the soliton decreases with the increasing of the quantum statistic effects. By using the numerical investigations, the interaction law of the nontrivial line-solitons with rich web structure in the interaction area among the line-solitons is studied by the Wronskian determinant method, which shows that there is no exchange of the energy, the momentum, and the angular momentum in the interaction. [ABSTRACT FROM AUTHOR]

It is found that the zero-order current associated with electron shear flow produces a drift wave in magnetized plasmas, which can become unstable under certain conditions. This wave will be particularly important in low density and low temperature plasmas of heavy ions. As an example, numerical estimates are presented for a barium plasma with parameters compatible with experiments. [ABSTRACT FROM AUTHOR]