Plasma Physics for Astrophysics

Transcription

1 - ' ' * ' Plasma Physics for Astrophysics RUSSELL M. KULSRUD PRINCETON UNIVERSITY E;RESS '. ' PRINCETON AND OXFORD,, ', V.

2 List of Figures Foreword by John N. Bahcall Preface Chapter 1. Introduction How Do We Describe a Plasma and Its Electromagnetic Fields? 6 References 13 Chapter 2. Particle Motions Motion in a Uniform Magnetic Field Motion of a Particle in a Nonuniform Magnetic Field Magnetic Mirrors Polarization Drift Adiabatic Invariants The Motion of Trapped Particles in the Magnetosphere Particle Motion and Macroscopic Force Balance Problems ' 37 References 39 Chapter 3. Magnetohydrodynamics The Basic Equations Flux Freezing Applications of Flux Freezing The Symmetric Cases Stellar Collapse The Solar Wind and the Magnetosphere Stellar Formation and the Angular Momentum Problem \ Magnetic Fields in Turbulence Io and Jupiter Motions of Lines of Force in a Vacuum The Validity of the MHD Equations Pulsar Magnetospheres Problems. 67 References 70 Chapter 4. Conservation Relations Introduction The Lorentz Force Conservation of Linear Momentum Conservation of Angular Momentum Conservation of Energy The Virial Theorem The Action Principle for MHD ' 86 xi xv xvii

3 viii 4.8 Lundquist's Identity Axisymmetry Problems 100 References 102 Chapter 5. MHD Waves The Basic Equations The Intermediate Wave, The Fast and Slow Modes The Nature of the Fast and Slow Modes The Friedricks Diagram The Number of Modes Wave Energy and Momentum Waves in Nonuniform Media The Variation in Amplitude Wave Pressure Problems 126 References 127 Chapter 6. Nonlinear Steepening and Shocks Nonlinear Steepening Shocks MHD Shocks The Shock Thickness and Collisionless Shock Waves Problems 148 References 150 Chapter 7. The Energy Principle and Instabilities Stability The Energy Principle Instabilities The Interchange Instability The Parker Instability The Interchange without Gravity : Line Tying and Shear The Magnetorotational Instability (MRI) Problems 193 References 196 Chapter 8. Collisions and the Braginski Equations Introduction Binary Collisions The Fokker-Planck Equation Collision Rates The Space-Dependent Fokker-Planck Equation The Fluid Equations Transport Effects The Braginski Equations Properties of the Transport Coefficients 228

4 ix 8.10 Summary An Example Maxwellian Collisions Problems 241 References 244 Chapter 9. Collisionless Plasmas Introduction Dispersion Relation for Cold Plasma Waves Parallel Propagation The Number of Waves Perpendicular Propagation Propagation in a General Direction The Cold Plasma Approximation Faraday Rotation and Magnetic Fields Bremsstrahlung Wave Energy Problems 266 References 268 Chapter 10. Collisionless Plasmas: Thermal Effects Introduction Ion Acoustic Waves « The Dielectric Constant Landau Damping Physical Picture of Landau Damping Types of Resonances The Drift Kinetic Equation Problems 295 References 298 Chapter 11. Nonlinear Phenomena Introduction, Wave-Particle Interactions >; Wave-Wave Interactions Mode Decay Nonlinear Landau Damping Particle Trapping The Wave Kinetic Equation Kolmogoroff Turbulence MHD Turbulence An Exact Solution The Wave Interactions The Goldreich-Sridhar Theory Problems 339 References 342 Chapter 12. Cosmic Rays Physical Properties of Cosmic Rays 343

5 x 12.2 Pitch-Angle Scattering of Cosmic Rays by Alfven Waves The Cosmic-Ray Alfven-Wave Instability Quasilinear Diffusion of Cosmic Rays A Model for Cosmic-Ray Propagation with Sources and Sinks Cosmic-Ray Pressure and Energy Fermi Acceleration and Shock Acceleration of Cosmic Rays Problems 383 References 385 Chapter 13. Astrophysical Dynamos Introduction Cowling's Theorem Parker's Model for the Earth's Dynamo The Mean Field Dynamo Theory Derivation of the Mean Field Equations The Growth Rate of Dynamo Modes in the Galactic Disk Protogalactic Origin of the Magnetic Field The Biermann Battery The Protogalactic Dynamo Small-Scale Fields Problems 416 References «418 Chapter 14. Magnetic Reconnection Introduction The Sweet-Parker Model of Magnetic Reconnection The Uzdensky Model Comparison of the Sweet-Parker Model with Observations Petschek's Model for Magnetic Reconnection Non-MHD Reconnection Anomalous Resistivity Petschek Reconnection Revisited Which Is the Correct Reconnection Velocity? i ; The Case When the Guide Field Is Nonzero Hall Reconnection Problems 454 References 457 Suggested Further Reading 458 Index 459