Magnetospheric Currents

Magnetospheric Currents......Page 1
CONTENTS......Page 5
PREFACE......Page 9
Birkeland's First Years in Research......Page 11
Birkeland's Auroral Work......Page 12
The Discovery of the Polar Elementary Storm......Page 13
How Birkeland Explained Polar Elementary Stormsand Deduced Auroral Electric Currents......Page 18
Birkeland's Personality......Page 20
What Was He Really Like?......Page 23
The 1918 Paper......Page 27
The 1927 Paper......Page 29
Concluding Remarks......Page 31
Birkeland......Page 32
Chapman and Alfven......Page 34
Eventual Outcome......Page 35
Analysis......Page 36
References......Page 37
Introduction......Page 39
Sq Current......Page 41
Ring Current the Symmetric Component......Page 42
Current Systems Driven by the Solar Wind-Magnetosphere Dynamo SMD......Page 44
Substorm Current System......Page 45
Cusp Current System......Page 51
Concluding Remarks......Page 52
References......Page 53
The Magnetopause Currents......Page 59
The Ring Current......Page 63
The Tail Currents......Page 65
The Birkeland or Field Aligned Currents......Page 66
Sources of the Magnetospheric Currents......Page 68
Summary......Page 70
References......Page 71
Definitions and determinations......Page 73
Outline of the Method and its Numerical Tests......Page 77
Conductivity Models......Page 79
Electric Potential......Page 81
Ionospheric Currents......Page 82
Joule Heating......Page 83
Conclusion......Page 84
References......Page 85
1. Introduction......Page 87
2. Auroral Break-Up and WestwardTravelling Surges......Page 88
3. Eastward Drifting Omega Bands......Page 91
References......Page 94
Introduction......Page 96
Solar Wind Control of Polar Cap Currents......Page 97
Relationship with Birkeland Currents......Page 99
Discussion and Outstanding Problems......Page 102
References......Page 104
Correlation Between Electric andMagnetic Fields......Page 106
Relations With Particle Precipitationin the Evening Sector......Page 108
Current Densities......Page 110
References......Page 112
Modelling Procedures......Page 114
Case I - Classic Profiles......Page 115
Case II - Structured Profiles......Page 118
Discussion and Conclusions......Page 123
References......Page 124
Introduction......Page 125
Reversed Field-Aligned Currents Poleward of Region 1 Currents......Page 126
Reversed Convection-Type Ionospheric Currents atHigh Latitudes......Page 128
Conclusions......Page 129
References......Page 131
Data and Results......Page 133
References......Page 139
Data Management......Page 141
Conclusions......Page 144
REFERENCES......Page 146
Introduction......Page 147
Observations......Page 148
Ionospheric Currents......Page 149
Field-Aligned Currents......Page 150
Comparison with DE-2 Observations......Page 153
References......Page 155
Direct Detection of Currents......Page 157
Field-aligned Currents at the Plasma Sheet Boundary......Page 158
Field-aligned Currents at an Electric Field Discontinuity......Page 161
References......Page 167
Introduction......Page 168
Summary......Page 179
Introduction......Page 181
Quasi-Steady Reconnection and Flux Transfer Events......Page 183
Sample Observations of Quasi-Steady Reconnection, MagnetosheathFTEs, and a Magnetospheric FTE......Page 185
Field-Aligned Currents in FTE Flux Tubes......Page 186
Conclusions......Page 188
References......Page 189
Background Radiation......Page 190
Precipitating Electron Flux......Page 191
Electron Fluxes from Ionization Profiles......Page 193
Global Optical Techniques......Page 194
Strengths and Weaknesses of the Models......Page 195
Effects of Conductivity Modelson Other Modeling Efforts......Page 196
Conclusions......Page 199
References......Page 200
Evening Sector......Page 202
Effects of Conductivity onField-Aligned Currents......Page 204
Summary......Page 208
References......Page 209
MAGNETOSPHERIC DYNAMO PROCESSES......Page 210
The Io?Jupiter Interaction......Page 212
The Tail Dynamo......Page 214
References......Page 217
Questions and Answers......Page 218
Open Field Lines in the Polar Cap......Page 222
Birkeland Currents......Page 226
Field Topology......Page 227
Summary and Conclusions......Page 230
REFERENCES......Page 231
Introduction......Page 233
The Boundary Layer Current......Page 236
The "Distant" Cross-Tail Current......Page 239
Additional Currents from the Interplanetary Medium......Page 240
Discussion......Page 242
References......Page 243
Introduction......Page 244
References......Page 250
Introduction......Page 251
Tangential Discontinuities With Electron Acceleration......Page 252
Rotational Discontinuities Without Electron Acceleration......Page 253
Rotational Discontinuities With Electron Acceleration......Page 255
References......Page 256
Introduction......Page 257
Model Inputs......Page 258
Global Ionospheric Conductance......Page 259
Event Simulations......Page 260
Electric Fields......Page 261
Current Systems......Page 262
Conclusion......Page 267
References......Page 268
Geometrical Assumptions and Idealizations......Page 270
The Equipotential Nature of Ring 2......Page 271
Solution for the Viscous-Like Interaction......Page 273
Solution for the Magnetic Merging Interaction......Page 274
Directly and Indirectly Driven Processes......Page 275
References......Page 277
Analytic Stability Analysis......Page 279
Computer Model and Results......Page 283
Conclusion......Page 284
References......Page 285
Discussion......Page 286
Introduction......Page 294
Distributions of Field-Aligned Currents......Page 295
Field-Aligned Currents and the Structure ofthe Magnetosphere......Page 298
Three-Dimensional Current Systems......Page 300
Discussion......Page 301
References......Page 302
Introduction......Page 304
Observations......Page 305
Discussion......Page 309
References......Page 312
Introduction......Page 314
Overview of the Association of Field-Aligned Currents and Auroral Processes......Page 315
A. Electrostatic Shocks......Page 316
B. Ion Beams......Page 317
C. Electrostatic Ion Cyclotron Waves......Page 318
E. Double layers......Page 319
Discussion and Conclusions......Page 321
References......Page 322
The Need For Three-Dimensional Models......Page 325
Particle Conservation......Page 326
The Magnetospheric Generator And Charge Conservation......Page 328
The Distribution Of The Parallel. Electric Field......Page 330
Summary......Page 331
References......Page 332
Introduction......Page 335
Dusk Region I and Harang Discontinuity Currents......Page 336
Summary......Page 339
References......Page 340
Introduction......Page 341
Observations......Page 342
Model......Page 346
Discussion......Page 347
References......Page 348
Rotational Currents......Page 350
The Centrifugal Current......Page 351
The Coriolis Current......Page 353
The Acceleration Current......Page 354
Other Dynamo Current Systems......Page 355
The Io Current System......Page 356
Solar-Wind Coupling......Page 357
References......Page 358
Terrestrial Birkeland Currents......Page 360
Jovian Birkeland Currents......Page 364
References......Page 366