Nonlinear Wave and Plasma Structures in the Auroral and Subauroral Geospace

Nonlinear Wave and Plasma Structures in the Auroral and Subauroral Geospace
Copyright
Preface
1. Introduction: near-Earth space environment
	1.1 Bow shock
	1.2 Magnetosheath
	1.3 Polar cusps
	1.4 Magnetosphere
		1.4.1 Magnetotail
		1.4.2 Plasmasphere
		1.4.3 Radiation belts
		1.4.4 Ring current
	1.5 Ionosphere
		1.5.1 Ionospheric regions
		1.5.2 Ionospheric conductivities
	1.6 Electric currents
	1.7 Aurora and auroral oval
	1.8 Magnetosphere-ionosphere (MI) coupling
	References
2. Plasma waves and instabilities
	2.1. Plasma waves
		2.1.1 Background
			2.1.1.1 Plasma: the fourth state of matter
			2.1.1.2 Maxwell\'s equations and dielectric permittivity
			2.1.1.3 Plane waves
			2.1.1.4 Dispersion and wave equations
			2.1.1.5 Hydrodynamic approach
			2.1.1.6 Kinetic approach
		2.1.2 Drift in static magnetic fields
			2.1.2.1 Cyclotron rotation
			2.1.2.2 E × B drift
			2.1.2.3 Polarization and Pedersen drift
			2.1.2.4 Guiding center
			2.1.2.5 Gradient-curvature drift
		2.1.3 Cold plasma
			2.1.3.1 Unmagnetized plasma
			2.1.3.2 Magnetized plasma
				High- and low-frequency potential oscillations
				Electromagnetic modes
		2.1.4 Warm plasma waves
			2.1.4.1 Unmagnetized plasma
				Langmuir waves
				Ion sound waves
				Collisional damping and wave energy
				Resonant interaction and Landau damping
			2.1.4.2 Warm magnetized plasma
				Cyclotron resonances
				Upper hybrid and electron Bernstein waves
				Low-frequency waves
		2.1.5 Wave propagation in inhomogeneous plasmas
			2.1.5.1 Wave–particle analogy
			2.1.5.2 Unmagnetized plasma layer
				Oblique incidence
			2.1.5.3 Magnetized plasma layer
				Normal incidence
				Oblique incidence
		2.1.6 Magnetohydrodynamic waves
			2.1.6.1 MHD equations
			2.1.6.2 Equations of ideal MHD
				Alfvén waves
				Magnetosonic waves
			2.1.6.3 Dispersive Alfvén waves
				Inertial Alfvén waves
				Kinetic Alfvén waves
		2.1.7 Appendix A2.1: dielectric permittivity of a magnetized plasma
			2.1.7.1 Potential waves
			2.1.7.2 Bi-Maxwellian distribution
				High-frequency limit
				“Ring” or “beam of oscillators”
				Drifting distribution
				Low-frequency limit
				Perpendicular propagation
				Imaginary part of the dielectric permittivity
			2.1.7.3 Electromagnetic waves
				Dielectric permittivity tensor
				Parallel propagation
				Perpendicular propagation
				Bernstein and extraordinary modes
				Tensor for a Maxwellian distribution
			2.1.7.4 Useful identities
				Bessel functions
				Integrals
				Limits
		References
		Recommended reading
	2.2. Plasma instabilities
		2.2.1 Introduction: nonequilibrium plasma
		2.2.2 Unmagnetized plasma
			2.2.2.1 Cold electron beam instability
			2.2.2.2 The Buneman instability
				Negative energy waves
			2.2.2.3 Kinetic instabilities: inverse Landau damping
				Electron “bump-on-tail” instability
				Inhomogeneity effect
				Ion sound instability
		2.2.3 Magnetized plasma
			2.2.3.1 Cold parallel electron beam
			2.2.3.2 The Buneman instability in the magnetic field
			2.2.3.3 Electron “ring/oscillators” instability
			2.2.3.4 Cold perpendicular ion beam
				Modified two-stream instability
				Ion “ring/oscillators” instability
			2.2.3.5 Electron “bump-on-tail” instability in the magnetic field
			2.2.3.6 Field-aligned current-driven instability
			2.2.3.7 Perpendicular ion “bump-on-tail” instability
			2.2.3.8 Nonequilibrium distributions of perpendicular velocities
				Warm electron ring
				Anisotropic electron population
				Anisotropic electron beam
		2.2.4 Interchange instabilities
			2.2.4.1 Rayleigh–Taylor instability
			2.2.4.2 Gradient-drift instability
		2.2.5 Current convective instability
		2.2.6 Drift instabilities
			2.2.6.1 Drift waves
			2.2.6.2 “Weak” and “strong” inhomogeneity
			2.2.6.3 Dissipative drift instability
			2.2.6.4 Kinetic drift instability
				Cold ions
				Warm ions
				Unmagnetized ions
			2.2.6.5 Temperature gradient instability
			2.2.6.6 Temperature-gradient drift instability
				Dissipative TGI
				Collisionless TGI
		2.2.7 The Farley–Buneman instability
		2.2.8 Appendix A2.2: Dielectric permittivity of an inhomogeneous plasma
			2.2.8.1 Integrals of motion
			2.2.8.2 Drifting distribution
			2.2.8.3 Low frequencies
			2.2.8.4 High frequencies
			2.2.8.5 Perpendicular propagation
		References
		Recommended reading
	2.3. Nonlinear interactions
		2.3.1 Introduction
		2.3.2 Resonant wave–particle interactions
			2.3.2.1 One mode interaction
			2.3.2.2 Nonlinear regime of Landau damping
			2.3.2.3 Collisions and plasma inhomogeneity effects
			2.3.2.4 Saturation of the hydrodynamic beam instability
			2.3.2.5 Quasilinear theory
			2.3.2.6 Initial problem
			2.3.2.7 Boundary problem
			2.3.2.8 Electron collisions effect
			2.3.2.9 Inhomogeneity effect
		2.3.3 Weakly nonlinear wave interactions
			2.3.3.1 Induced scattering
			2.3.3.2 Inverse cascade
			2.3.3.3 Kinetic wave equation
			2.3.3.4 Wave–wave interactions
			2.3.3.5 Matching conditions
			2.3.3.6 Ponderomotive force
			2.3.3.7 Zakharov equations
			2.3.3.8 Parametric decay instability
			2.3.3.9 PDI in an inhomogeneous plasma
			2.3.3.10 Modified decay instability
			2.3.3.11 Modulational instability
			2.3.3.12 Weakly magnetized plasma
			2.3.3.13 Upper hybrid parametric decay
			2.3.3.14 Lower hybrid parametric processes
			2.3.3.15 Nonlinear saturation of weakly turbulent processes
		2.3.4 Strong turbulence
			2.3.4.1 Langmuir collapse
			2.3.4.2 Strong Langmuir turbulence
			2.3.4.3 Conversion (scattering) on ion density fluctuations
			2.3.4.4 Effect of collisional damping
			2.3.4.5 Acceleration of plasma electrons
			2.3.4.6 Magnetized Langmuir collapse
			2.3.4.7 Strong lower hybrid turbulence
		2.3.5 Nonlinear inertial Alfvén waves
			2.3.5.1 Nonlinear equations
			2.3.5.2 Parametric decay of inertial Alfvén waves
			2.3.5.3 Electrostatic convective cells
		2.3.6 Appendix A2.3: useful formulas
			2.3.6.1 Elliptic integrals
			2.3.6.2 Nonlinear unit-mass pendulum
			2.3.6.3 Averaging over statistical ensemble
		References
3. Auroral geospace
	3.1. Earthbound injections in the magnetotail
	3.2. Substorms
	3.3. Multiscale aurora: structure and dynamics
	3.4. Alfvénic aurora
4. Nonlinear effects in natural and artificial aurora
	4.1. Energetic electron impact on the upper atmosphere
		4.1.1 Auroral emissions
		4.1.2 “Classical” aurora
			4.1.2.1 Energy deposition
			4.1.2.2 Degradation spectrum
			4.1.2.3 SPA plasma composition
		4.1.3 Enhanced Aurora
			4.1.3.1 Luminosity/ionization profiles
			4.1.3.2 Spectra of Enhanced Aurora and suprathermal electrons
			4.1.3.3 Plasma composition
		References
	4.2. Artificial aurora
		4.2.1 Electron beam experiments
			4.2.1.1 Near-rocket glow
			4.2.1.2 Suprathermal electrons
			4.2.1.3 VHF electromagnetic emissions
			4.2.1.4 Prompt electron echoes
			4.2.1.5 Artificial aurora rays
		4.2.2 High-power HF heating experiments
			4.2.2.1 Descending artificial airglow
			4.2.2.2 Suprathermal electrons
			4.2.2.3 Daytime artificial ionization layers
		References
	4.3. Theory of Artificial and Enhanced Aurora
		4.3.1 Electron beam interaction with the ionosphere
			4.3.1.1 Collisionless relaxation of electron beams
			4.3.1.2 Collisional effects in the beam-driven Strong Langmuir turbulence
				Heating and acceleration of plasma electrons
					Collision integral
					Accelerated electron distribution
					Ionization rate
					Inelastic loss coefficient
				Plasma-turbulence layer
		4.3.2 Beam-plasma discharge in artificial aurora experiments
			4.3.2.1 BPD basics
			4.3.2.2 BPD ignition in the ionosphere
				Instability of a bounded electron beam
				Instability saturation
				Fast electron heating
				Drift of the beam guiding center
			4.3.2.3 Intermittent BPI
				Prompt electron “echoes”
				BPD during the off period
					Heat flux-driven instability
			4.3.2.4 “Quasi-stationary” BPD
				Cold beam
				“Warm” beam
				Optical emission from the near-rocket glow
				Radioemission from the near-rocket region
		4.3.3 Theory of descending artificial plasma layers
			4.3.3.1 Ionizing wave via HF-driven SLT acceleration
				Coexistence of the WT and SLT regimes
				Numerical simulation of descending layers
				SLT and mitigation of anomalous absorption near the upper hybrid resonance
		4.3.4 SLT signatures in the auroral ionosphere
		4.3.5 Thermal electron distribution in the F-region
		References
	4.4. E/F-region turbulent heating
		4.4.1 Langmuir turbulence and FAC-driven instability
		4.4.2 Energy balance in weakly ionized ionosphere
		4.4.3 The Farley–Buneman instability effects
		4.4.4 Plasma chemistry in the heated E-Region
			Nonequilibrium species
		References
5. Subauroral geospace
	5.1. Subauroral flows
	5.2. Subauroral ULF wave structures
	5.3. Subauroral arcs
	5.4. Generation and dynamics of subauroral VLF whistlers
Index
	A
	B
	C
	D
	E
	F
	G
	H
	I
	K
	L
	M
	N
	O
	P
	Q
	R
	S
	T
	U
	V
	W
	X
	Z