Books published by the Center include undergraduate, graduate, and workshop textbooks; handbooks and manuals; reference books; monographs; specialized reviews; and DOE-sponsored symposium, workshop, and short-course proceedings. FOR E w ORD This publication is the second in the Advances in Fusion Science and Engineering series, a part of the DOE Critical Review Series. The purpose of the Advances in Fusion Science and Engineering series is to provide the fusion research community with high-quality reviews in specialized areas of fusion science and engineering. Although Alfvtn waves have been the subject of study in space plasmas for a long time, only recently have plasma dimensions and betas reached sufficiently high values to make it possible to study Alfvtn waves in the laboratory. Auxiliary heating by means of Alfvdn waves has been tried both in the United States and abroad. Preliminary indications are that heating may be possible with the very high absorption efficiency predicted by theory. Because of the localized nature of wave conversion, Alfvin waves have the potential of providing plasma profile control. Alfvdn waves have recently been proposed for space-resolved measurement of magnetic fields in tokamaks and may become important as a diagnostic tool in the future. This monograph deals with. the properties of Alfvin waves and with their application to fusion. The book is divided into seven chapters dealing with linear properties in homogeneous and inhomogeneous plasmas. Absorption is treated by means of kinetic theory. Instabilities and nonlinear processes are treated in Chapters 1 to 6 , and the closing chapter is devoted to theory and experiments in plasma heating by Alfvtn waves. V vi FOREWORD I n view of the growink importance to the tokamak program of auxiliary heating by means of electromagnetic waves, I believe this monograph will fill a need for an exposition of the essential elements of AlfvCn waves, with emphasis on geometries relevant to tokamaks. The extensive reference section at the end of each chapter will assist the reader in expanding his knowledge of the subject.

A three-dimensional nonlinear Kadomtsev–Petviashvili (K–P) wave equation is derived to discuss the solitons in multicomponent plasma contaminated with negative ions. A new formalism of the simple wave solution method is developed for finding the soliton behaviors caused by the presence of negative ions in plasmas. It is seen that the nonlinear wave equation leads, in some cases, to an ordinary differential equation and a straight way for solving the soliton propagation in plasmas. The overall observations describe the natures of compressive and rarefactive solitons along with the shock-like wave caused by the interaction of negative ions. Also discussed are the possible controls of the scenarios of soliton behaviors. Moreover it is believed, from present investigations, that the observations of collapses or explosions in solitons could enhance the understanding of the soliton phenomena in laboratory and space plasmas.

A simple model of plasma with two positive and one negative ionic species is used to study the effect of negative ions on the crossover frequencies in a multicomponent plasma. Both qualitative and quantitative results show very interesting features of the existence and behavior of crossover frequencies, especially when the negative ion mass has a value intermediate to the values of the two positive ion masses.

It is shown that, although the mathematical analysis of the Alfvén-wave equation does not show any variation at non-zero or zero singular points, the role of surface waves in the physical mechanism of resonant absorption of Alfvén waves is very different at these points. This difference becomes even greater when resistivity is taken into account. At the neutral point the zero-frequency surface waves that are symmetric surface modes of the structured neutral layer couple to the tearing mode instability of the layer. The importance of this study for the energy balance in tearing modes and the association of surface waves with driven magnetic reconnection is also pointed out.

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The properties and resonant absorption mechanism of the Alfvén compressional waves are discussed for a cold plasma. The parametric analysis of the dispersion equation shows that unlike the incompressible case the excitation of the compressional surface waves near the resonant surface depends on the specific values of the plasma parameters across this surface. The oscillation frequency and the resonant absorption coefficient of these waves also show a different behavior from those of Alfvén waves. The phase velocity ω/k∥ depends on the perpendicular wave number k⊥, and the absorption coefficient is proportional to (Ka)2/3, where K = (k∥² + k⊥)1/2 and 2a is the scale length of the density variation.

Abstract. We show that with reasonable values of anomalous resistivity, surfacewave-induced magnetic reconnection at an interface between two plasma regions (such as the magnetosheath and the magnetopause) has an intrinsic timescale that can explain observations of a delay time between the southward turning of the interplanetary magnetic field and the onset of a flow transfer event at the magnetopause.

Despite many theoretical studies on soliton formation and its propagation in plasmas, no study with multicomponent magnetized plasma has derived the special nonlinear wave equation, called the Zakharov–Kuznetsov equation [V. E. Zakharov and E. A. Kuznetsov, Sov. Phys. JETP 39, 285 (1974)]. Thus, the main emphasis has been given to employing the hyperbolic-type method for finding the soliton features in relation to laboratory and space plasma environments. Where this method has been unsuccessful, an alternate method has been developed to yield the soliton propagation. The features of the nonlinear plasma-acoustic waves, which depend on the plasma composition, affect the coexistence of compressive and rarefactive solitary waves. Later, allowing for the higher order nonlinearity in the dynamics, one is led to further different solitary waves along with double layers. The main aim of the present study is to use a new formalism for finding the soliton propagation from the nonlinear wave equation with strong, as well as weak, nonlinearity. The coexistence of different nonlinear acoustic modes due to the interaction of multiple charges in plasma is shown. Moreover, the theoretical observations revealed many other soliton-like structures, which could be similar to the dip and hump solitons observed by the Freja Scientific Satellite and the collapsed solitons expected in the propagation of solar flares, as well as in the interplanetary space plasmas.