A theoretical analysis of the anomalous skin effect in cylindrical plasma is carried out for a model where the radial electron-density distribution is of Gaussian form. It is shown that there are major qualitative differences between the results for cylindrical and those for plane geometry. Calculations of the electromagnetic field distribution over the plasma cross-section show that the present theory is in satisfactory agreement with experiment.

The influence of a steady axial magnetic field on the anomalous penetration of low frequency electromagnetic fields into a cylindrical plasma column is investigated by considering a plasma with a Gaussian electron density distribution. For this model, a complete solution is obtained for Boltzmann's equation coupled to Maxwell's equations, and the fields calculated exactly. The results show dramatic changes of the internal fields for small changes of the applied magnetic field when the average Lamour radius of the electrons is of the order of the plasma radius.

The propagation of slow surface waves in an inhomogeneous plasma is investigated. Both ‘axial’ and ‘radial’ density gradients n(r) and those of the static magnetic field B0 are taken into account. It is demonstrated that the axial in- homogeneities n(z) and B0(z) result in the dependence of the natural surface- wave frequencies on the ‘axial’ co-ordinate z. The dependence ωSW(z) affects the phase velocity νph = ωswsol;K where K iS the propagation constant. So, in the case of surface-wave excitation by a charged particle beam in an ‘axially’ inhomogeneous plasma, the Cherenkov resonance ωSW= KV0 between the beam and the surface waves breaks, thereby reducing the growth rate of unstable oscillations. This phenomenon might be considered as the stabilization of the beam by the ‘axial’ density gradient. It is also shown that the ‘radial’ gradients n0(r) and B0(r) essentially affect the surface-wave natural frequencies as well. Dispersion equations, expressions for the natural frequencies and growth rates are obtaind, taking into account the gradients of the density and the static magnetic field.

The field of a small (Hertzian) dipole excited on a fixed frequency in warm electron plasma streaming atsuperthermal velocity is approximated electrostatically. The plasma is described by a hydrodynamic model, without collisions or magnetic field. The mutual impedance for two such dipoles is studied, to determine the geometrical structure of the field, and in particular to locate the Cherenkov cone of slow plasma waves excited by the source.

The inhomogeneous sheath that surrounds a probe immersed in a weakly collisional magnetized plasma is investigated from the microscopic point of view, in the case when the probe is cylindrical and parallel to the magnetic field. Arbitrary surface effects of the probe (such as absorption, reflexion and emission of particles) are taken into account. The sheath is described with a model based on the solution of a boundary-value problem for the self-consistent Boltzmann—Maxwell—Poisson equation. The spatial variation of the magnetic field is discussed. Typical results of numerical computations concerning the structure of the sheath and the currents collected by the probe are given and discussed.

Previously derived shock solutions for a perfectly conducting perfect gas are used to compute shock polars for the one-dimensional unsteady and two- dimensional non-aligned shock representations. A new special-case shock solution, having a downstream particle velocity relative to the shock equal to upstream Alfvén velocity, is obtained, in addition to exhaustive analytical classification schemes for the shock polars. Eight classes of one-dimensional polars and twelve classes of two-dimensional polars are identified.

A previously developed set of kinetic model equations for a chemically-reacting gas is modified. By examining closely the H theorem, a new set of constraints is obtained. These conditions are then used to determine the inelastic collision parameters proposed in the model. The kinetic equations so obtained are able to produce exactly the same rate equations as prescribed by the actual chemical reactions.

In the neo-classical theory of transport process in a toroidal plasma with long mean free path, the value of the poloidal rotation is determined by ambipolarity. This paper investigates the time-dependent phase during which this rotation develops. Diffusion arises from resonant particles, for which v∥ ≃ Er /Bφ. The time a particle spends in resonance, and hence its radial displacement, is now determined by the rate of change of Er, rather than collisional scattering. The time for Er to approach its quasi-stationary value is comparable to the mean time for an ion to travel the connexion length. This is short compared with typical experimental durations. The mass flow also builds up parallel to the magnetic field, but its contribution to the poloidal flow is small compared with the Er /B electric drift.

A similarity technique is used to solve the problem of the ion rarefaction wave associated with a sheath growing at constant speed from a cylindrical or spherical probe into an infinite plasma.

The stability of a magneto-sonic wave of small (but finite) amplitude, propagating in a low- β plasma across a magnetic field, is investigated. It is shown that such a wave is unstable with respect to parametric splitting into many satellite waves. Wavenumbers of the satellite waves differ from that of the original magneto-sonic wave. Thus, the sateffite waves leave an interaction space, and form oscillating ‘tails ’ in front of and behind the initial pulse.