The present paper is a coherent account of various aspects of longitudinal oscillations in one and two component plasmas. A discussion is offered of dispersion equations, conditions necessary for the growth or decay of oscillations, the physical mechanisms of growing or damping, and the possibility of arbitrary steady-state solutions. The physical situation is described in terms of Poisson's equation and the Boltzmann equation, while the mathematical description is in terms of solutions of an initial-value problem in the small amplitude (linearized) approximation. Some general results are derived for an arbitrary unperturbed velocity distribution of electrons and ions. From these expressions the customary results for a stationary plasma in thermal equilibrium can readily be obtained. For simplicity, one dimensional motion of a simple one component plasma is treated in detail; appropriate generalizations for two or more component plasmas (electrons and ions) are, however, indicated in text. Collisions between particles and non-linear effects are not considered, nor are the effects of external electric or magnetic fields.
J D Jackson 1960 J. Nucl. Energy, Part C Plasma Phys. 1 171
V Kopecký and J Václavík 1966 J. Nucl. Energy, Part C Plasma Phys. 8 645
Instability of the drift-dissipative type, of a weakly ionized non-isothermal plasma in crossed electric and magnetic fields (Simon; Hoh) has been studied in the quasi-classical approximation for two cases: (a) Ωeτe ≫ 1, Ωiτi ≫ 1, (b) Ωeτe ≫ 1, Ωiτi ≪ 1. The increment and frequency of the instability of such a plasma against potential disturbances have been deduced in the linear approximation. Equations of strong turbulence evolved with the aid of Mikhailovskii's diagram method have been used in estimating the maximum value of the spectrum function of the electric field of oscillations and of the coefficient of turbulent diffusion. The concluding part of the paper presents a set of equations of strong turbulence in the dimensionless form suitable for computer analyses.
V D Shafranov 1966 J. Nucl. Energy, Part C Plasma Phys. 8 109
D E T F Ashby and B E Avis 1966 J. Nucl. Energy, Part C Plasma Phys. 8 1
A coaxial gun is used to inject a burst of energetic, low-density hydrogen plasma along the axis of the magnetic field produced by a long solenoid. The portion of this plasma which penetrates the magnetic field has a density of 1011-1012 electrons/cm3 and a mean directed energy of 10-20 keV. The properties of the plasma have been studied as it moves along the magnetic field. The mean ion velocity perpendicular to the magnetic field has been measured with Faraday Cups and the transverse energy of the plasma has been deduced from its diamagnetism. These measurements show that the transverse energy of the plasma resides predominantly in the ions which have considerable angular momentum. It is shown that this momentum is produced by electrons flowing from the vicinity of the vacuum chamber walls as the plasma enters the cusp-shaped field at the end of the solenoid.
P F Little and B E Avis 1966 J. Nucl. Energy, Part C Plasma Phys. 8 11
Coaxial plasma guns operating with about 20 kV applied at a peak current of approximately 80 kA are shown to produce a fast burst of clean plasma containing no other ions than H+. Densities of about 1011 cm-3 are measured at distances of 100 cm from the gun for ions of energy between 5 keV and 20 keV: peak ion energies of about 70 keV are observed. In the slow plasma following the fast burst the impurity ions are mainly copper.
The ion density depends on the amount of gas admitted before firing the gun, but does not vary much with gun voltage.
The measured ion velocity perpendicular to the guide field is within a factor two of the predictions of a simple theory. Discrepancies are expected because the ions do not appear in a field-free region, as the theory assumes.
F W Crawford and H H Weiss 1966 J. Nucl. Energy, Part C Plasma Phys. 8 21
In recent years the importance of cyclotron harmonic waves has become apparent in many branches of plasma physics. For example, it has been demonstrated that they are involved in the anomalously high noise radiation near the electron cyclotron harmonic frequencies that has been observed from thermonuclear fusion study devices, and that they can explain the cyclotron harmonic resonances observed in satellite studies of the ionosphere. In this paper experiments on propagation perpendicular to a magnetic field in a low-pressure mercury-vapour discharge are described. This mode is particularly important since it is not subject to Landau damping. The relevant dispersion curves are compared with results of the experimental study, and show evidence of such transmission across the plasma, between two parallel cylindrical probes. Cyclotron resonance phenomena have many potential applications to plasma diagnostics, the theory of extra-terrestrial noise excitation and to microwave oscillators and amplifiers. Some of these are discussed briefly.