This book is a study of plasma waves which are observed in the earth's magnetosphere. The emphasis is on a thorough, but concise, treatment of the necessary theory and the use of this theory to understand the manifold varieties of waves which are observed by ground-based instruments and by satellites. We restrict our treatment to waves with wavelengths short compared with the spatial scales of the background plasma in the mag netosphere. By so doing we exclude large scale magnetohydrodynamic phenomena such as ULF pulsations in the Pc2-5 ranges. The field is an active one and we cannot hope to discuss every wave phenomenon ever observed in the magnetosphere! We try instead to give a good treatment of phenomena which are well understood, and which illustrate as many different parts of the theory as possible. It is thus hoped to put the reader in a position to understand the current literature. The treatment is aimed at a beginning graduate student in the field but it is hoped that it will also be of use as a reference to established workers. A knowledge of electromagnetic theory and some elementary plasma physics is assumed. The mathematical background required in cludes a knowledge of vector calculus, linear algebra, and Fourier trans form theory encountered in standard undergraduate physics curricula. A reasonable acquaintance with the theory of functions of a complex vari able including contour integration and the residue theorem is assumed.
Inhalt
I Propagation and Generation of Plasma Waves.- 1 Basic Equations.- 1.1 Introduction.- 1.2 Electromagnetic Equations.- 1.3 Fluid Equations.- 1.4 The Kinetic Equation.- 1.5 Poynting's Theorem.- 1.6 Harmonic Oscillations.- 1.7 The Wave Equation.- 1.8 Summary.- 2 Waves in a Uniform Cold Magnetoplasma - 1. Infinite Plane Waves.- 2.1 Introduction.- 2.2 Characteristic Frequencies and Speeds.- 2.3 Linearization of the Equation of Motion.- 2.4 Constitutive Relations.- 2.5 Plane Waves.- 2.6 Polarization.- 2.7 Properties of the Refractive Index.- 2.8 Energy Flux in a Plane Wave.- 2.9 Summary.- 3 Waves in a Uniform Cold Magnetoplasma - 2. Rays and Wave Packets.- 3.1 Introduction.- 3.2 Wave Packets and Rays.- 3.3 Classification of Waves in a Cold Plasma.- 3.4 Refractive Index and Dispersion Relation.- 3.5 Summary.- 4 Propagation of Electromagnetic Waves in a Non-Uniform Cold Magnetoplasma.- 4.1 Introduction.- 4.2 Plane Stratified Media.- 4.3 Ray Tracing in General Media.- 4.4 Summary.- 5 Waves in a Uniform Warm Magnetoplasma.- 5.1 Introduction.- 5.2 Characteristic Speeds.- 5.3 The Constitutive Relation.- 5.4 Dispersion Relations and Refractive Index.- 5.5 Polarization.- 5.6 Summary.- 6 Waves in a Hot Plasma - 1. General Features.- 6.1 Introduction.- 6.2 Unperturbed Particle Orbits.- 6.3 Electrostatic Approximation.- 6.4 Propagation Parallel to the Magnetic Field.- 6.5 Growth and Decay of Waves.- 6.6 The Equilibrium Distribution Function - The Maxwellian.- 6.7 Non-Equilibrium Distribution Functions.- 6.8 Summary.- 7 Waves in a Hot Plasma - 2. Equilibrium and Non-Equilibrium Distributions.- 7.1 Introduction.- 7.2 Waves in Plasmas in Thermal Equilibrium.- 7.3 Longitudinal Waves Excited by a Particle Beam.- 7.4 Electrostatic Waves Associated with Anisotropic Distributions.- 7.5 Summary.- 8 The Effect of Wave Fields on Energetic Particles.- 8.1 Introduction.- 8.2 Particle Resonance.- 8.3 Trajectories of Resonant Particles in Velocity Space.- 8.4 Diffusion in Velocity Space.- 8.5 Some Non-Linear Effects.- 8.6 Waves Resonant with a Test Particle.- 8.7 Summary.- II Applications of the Theory to Plasma Wave Observations.- 9 Magnetospheric Plasmas.- 9.1 Introduction.- 9.2 Structure of the Earth's Magnetosphere.- 9.3 Cold Plasma Populations in the Magnetosphere.- 9.4 Hot Plasma Populations.- 9.5 Waves in the Magnetosphere.- 9.6 Summary.- 10 Waves in the Plasmasphere - 1. Whistler Observations and Basic Theory.- 10.1 Introduction.- 10.2 Properties of the Whistler Mode.- 10.3 Observations of Whistlers.- 10.4 Elementary Theory of Whistlers.- 10.5 Use of Whistlers as a Magnetospheric Probe.- 10.6 Summary.- 11 Waves in the Plasmasphere - 2. Details of Whistler Propagation.- 11.1 Introduction.- 11.2 Lightning as a Source of Electromagnetic Radiation.- 11.3 Propagation in the Earth-Ionosphere Waveguide.- 11.4 Transmission of Whistlers Through the Ionosphere.- 11.5 Propagation of Unducted Whistlers.- 11.6 Propagation in Ducts.- 11.7 Summary.- 12 Waves in the Plasmasphere - 3. Ion Cyclotron Whistlers.- 12.1 Introduction.- 12.2 Observations.- 12.3 Ion Cyclotron Whistler Propagation in a Uniform Medium.- 12.4 Nature of Ion Cyclotron Whistler Generation.- 12.5 The Effect of Collisions on Coupling.- 12.6 Summary.- 13 Waves in the Plasmasphere - 4. Doppler Shifted Cyclotron Resonance of Electrons with Whistlers.- 13.1 Introduction.- 13.2 Some Relevant Observations.- 13.3 Whistler Wave-Particle Interaction in a Uniform Medium.- 13.4 Whistler-Mode Noise in a Non-Uniform Medium.- 13.5 Whistler-Mode Signals Generated by Energetic Particles.- 13.6 Summary.- 14 Waves in the Auroral Region.- 14.1 Introduction.- 14.2 Observations.- 14.3 Propagation of Whistler Mode Hiss.- 14.4 Z-Mode Radiation.- 14.5 Terrestrial Myriametric Radiation.- 14.6 Auroral Kilometric Radiation.- 14.7 Summary.- 15 Some Final Words.- 15.1 Introduction.- 15.2 Man-Made Plasma Waves.- 15.3 Ultra Low Frequency Pulsations.- 15.4 Waves in the Magnetotail, Magnetosheath and Solar Wind.- 15.5 Future Work.- A The Essence of Cartesian Tensors.- B Some Mathematical Results.- B.1 Properties of Bessel Functions and Related Results.- B.2 The Plasma Dispersion Function.- C Properties of the Earth's Dipole Field.- D Definition of Symbols.