Solar Dynamics and its Effects on the Heliosphere and Earth (eBook)

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TABLE OF CONTENTS 6
FOREWORD 8
ACTIVE REGION DYNAMICS 10
1. Introduction 10
2. New Methods of Investigating Solar Dynamics 11
3. Lifecycle of Active Regions 12
4. Dynamics of Active Regions and Sources of Heliospheric Disturbances 19
References 21
SUNSPOT STRUCTURE AND DYNAMICS 22
1. Introduction 22
2. The Magnetic Structure of a Sunspot 23
3. Flux Pumping by Convection 26
4. Outstanding Problems 27
Acknowledgements 30
References 30
CORONAL DYNAMICS AND THE AIA ON SDO 32
1. Introduction 32
2. Dynamics of the Inner Corona 33
3. The Observational Problem 33
4. The Atmospheric Imager Assembly (AIA) 36
5. Results of DEM Modeling Tests 39
Acknowledgements 41
References 41
WIND IN THE SOLAR CORONA: DYNAMICS AND COMPOSITION 43
1. Introduction 43
2. Fast Expansion in the Core of Large Polar Coronal Holes 44
3. Slow Expansion at the Edges of the Large Polar Coronal Holes and Between Sub- Streamers 49
4. Conclusions 56
Acknowledgements 57
References 57
SOLAR WIND SOURCES AND THEIR VARIATIONS OVER THE SOLAR CYCLE 59
1. Introduction 59
2. The Two Basic States of SolarWind 61
3. The FastWind in HSS and its Sources 64
4. The Low Speed SolarWind of Minimum Type (LSM) and its Sources 66
5. The Low Speed SolarWind at High Solar Activity (LSA) and its Sources 71
6. SolarWind in Context with Transients at the Sun 72
7. Variations over the Solar Activity Cycle 77
8. Summary 78
Acknowledgements 80
References 80
HELIOSPHERIC PHYSICS: LINKING THE SUN TO THE MAGNETOSPHERE 85
1. Introduction 85
2. Problem Definition 87
3. Potential Field Source Surface (PFSS) Models 89
4. Magnetohydrodynamic (MHD) Models 91
5. Alternative Approach 93
6. Summary 96
Acknowledgements 96
References 96
SUBSTORMS AND THEIR SOLAR WIND CAUSES 99
1. Introduction 99
2. Solar Wind Input Control of Near-Earth Reconnection 101
3. Different Modes of the Magnetotail Flux Transport 103
4. SolarWind Density Influences on Substorms 106
5. Conclusions 108
Acknowledgements 109
References 109
MODELING OF THE MAGNETOSPHERIC RESPONSE TO THE DYNAMIC SOLAR WIND 110
1. Introduction 110
2. Adiabatic Tail Evolution 111
3. Vlasov Models of Thin Current Sheets 117
4. Dynamic Evolution 118
5. Summary and Conclusions 121
Acknowledgements 122
References 122
REVIEW OF IONOSPHERIC EFFECTS OF SOLAR WIND MAGNETOSPHERE COUPLING IN THE CONTEXT OF THE EXPANDING CONTRACTING POLAR CAP BOUNDARY MODEL 124
1. Introduction 124
2. Ionospheric Convection 125
3. FTE Flow Signatures 127
4. Flow Excitation During Magnetospheric Substorms 132
5. Large-Scale Response of the Polar Ionosphere 132
6. Outstanding Questions 134
7. Summary 135
Acknowledgements 135
References 135
THE EVOLVING SIGMOID: EVIDENCE FOR MAGNETIC FLUX ROPES IN THE CORONA BEFORE, DURING, AND AFTER CMES 138
1. Introduction: The Magnetic Flux Rope Paradigm 138
2. Sigmoids 139
3. Dynamic Perturbations 143
4. Partly vs. Fully Expelled Flux Ropes 146
5. Conclusions 149
Acknowledgements 149
References 149
PROPERTIES OF INTERPLANETARY CORONAL MASS EJECTIONS 152
1. Introduction 152
2. An Observational Description of ICMEs 153
3. Statistical Properties 156
4. The Solar Connection 159
5. Composition Signatures 165
6. ICMEs and Geomagnetic Storms 169
7. Summary 171
Acknowledgements 172
References 172
GEOEFFECTIVITY OF CORONAL MASS EJECTIONS 176
1. Introduction 176
2. Propagation from the Sun to the Earth 178
3. Storms Seen in Geomagnetic Indices 179
4. What Determines the Geoeffectivity of ICMEs 183
5. The Strongest Storms of Cycle 23 184
6. Discussion and Conclusions 186
Acknowledgements 187
References 187
RING CURRENT DYNAMICS 189
1. Introduction 189
2. Brief Historical Outline 190
3. Basic Properties and Structure of the Ring Current 191
4. Sources of Ring Current Particles 195
5. Ring Current Formation 197
6. Ring Current Evolution and Decay 200
7. Concluding Remarks 204
Acknowledgements 205
References 205
PLASMASPHERE RESPONSE: TUTORIAL AND REVIEW OF RECENT IMAGING RESULTS 209
1. Introduction 209
2. Inner Magnetospheric Convection 212
3. Intra-Magnetospheric Plasma Coupling 215
4. Concluding Remarks 219
Acknowledgements 220
References 220
END-TO-END MODELING OF THE SOLAR TERRESTRIAL SYSTEM 223
1. Introduction 223
2. Numerical Modeling 224
3. Empirical Modeling 231
4. Summary and Conclusions 234
Acknowledgements 236
References 236
PARTICLE ACCELERATION BY THE SUN: ELECTRONS, HARD X- RAYS/ GAMMA- RAYS 238
1. Introduction 238
2. RHESSI Hard X-Ray/.-Ray Observations of Solar Flares 239
3. Energetic Ions at the Sun and SEPs at 1 AU 245
4. Energetic Electrons at the Sun and at 1 AU 247
Acknowledgements 252
References 252
PARTICLE ACCELERATION IN A THREE-DIMENSIONAL MODEL OF RECONNECTING CORONAL MAGNETIC FIELDS 254
1. Introduction 254
2. Multiple Scales and Magnetic Complexity in Solar Flares 255
3. Acceleration in Cellular Automata Models 257
4. Acceleration in Self-Consistent MHD Models 260
5. Discussion 262
Acknowledgements 264
References 264
THE SEED POPULATION FOR ENERGETIC PARTICLES ACCELERATED BY CME- DRIVEN SHOCKS 265
1. Introduction 265
2. Observations 267
3. Discussion 274
Acknowledgements 277
References 277
ACCELERATION OF SOLAR-ENERGETIC PARTICLES BY SHOCKS 280
1. Introduction 280
2. Mechanisms of Charged-Particle Acceleration 281
3. Solar Energetic Particles 288
4. Global Modeling 288
5. Summary and Open Issues 289
Acknowledgements 290
References 290
SOLAR ENERGETIC PARTICLE CHARGE STATES: AN OVERVIEW 292
1. Introduction 292
2. Measurement Techniques 293
3. Ionic Charge Composition in Gradual Events 295
4. Ionic Charge Composition in Impulsive Events 296
5. Energy Dependent Charge States – Mechanisms 297
6. Correlation Between Elemental Abundances and Ionic Charge States 299
7. Ionic Charge States in Corotating Interaction Regions 300
8. Summary 300
Acknowledgements 301
References 301
SOLAR ENERGETIC PARTICLE COMPOSITION, ENERGY SPECTRA, AND SPACE WEATHER 305
1. Introduction 305
2. Composition and Spectral Variations in SEP Events 306
3. SEP and CME Kinetic Energies 310
4. Radiation Hazards due to Solar Energetic Particles 311
5. Solar Energetic Particle Impacts on the Geospace Environment 313
6. SpaceWeather Challenges 314
Acknowledgement 316
References 316
COMMONALITIES BETWEEN IONOSPHERE AND CHROMOSPHERE 319
1. Introductory Remark 319
2. Neutral-Ion Coupling 320
3. Wave Drive from Below 321
4. Wave Heating from Above 322
5. Plasma Erosion and Cavitation 326
6. Final Remark 331
References 332
SHOCKS: COMMONALITIES IN SOLAR-TERRESTRIAL CHAINS 334
1. Introduction 334
2. Why Are There ShockWaves? 335
3. Commonalities and Differences 337
4. Shock Microphysics 338
5. Shock Variability 340
6. Diffuse Ion Acceleration 343
7. Conclusions 343
Acknowledgements 344
References 344
THEORY AND SIMULATION OF RECONNECTION 346
1. Introduction 346
2. Collisionless, or as it is Often Called, Anomalous Resistivity 348
3. The Structure of Reconnection in Three Dimensions 354
4. Summary 358
Acknowledgements 359
References 359
THE LOCALIZATION OF PARTICLE ACCELERATION SITES IN SOLAR FLARES AND CMES 362
1. Introduction 362
2. Particle Acceleration in Primary Flare Loops 363
3. Particle Acceleration in Secondary Flare Loops 365
4. Particle Acceleration in Open Magnetic Fields 368
5. Particle Acceleration in CMEs 370
6. Final Remarks 372
Acknowledgements 372
References 372