Shu T. Lai is currently a visiting scientist at the Space Propulsion Laboratory, Department of Aeronautics and Astronautics, Massachusetts Institute of Technology and a senior editor for "IEEE Transactions on Plasma Science". He is a fellow of the Institute of Electrical and Electronics Engineers. He was formerly a senior physicist at the Space Weather Center of Excellence, Space Vehicles Directorate, Air Force Research Laboratory (AFRL), Hanscom Air Force Base, Massachusetts.
Preface xi
Prologue: The Earth's Space Plasma Environment
P.1 The Solar Wind xiii
P.2 The Magnetosphere xiii
P.3 Geomagnetic Substorms xiii
P.4 Plasma Density xv
P.5 The Ionosphere xvi
P.6 The Auroral Region xvi
P.7 The Radiation Belts xviii
P.8 Relevance of the Space Plasma Environment to Spacecraft Charging xviii
P.9 References xx
Chapter 1: Introduction to Spacecraft Charging
1.1 What Is Spacecraft Charging? 1
1.2 What Are Some Effects of Spacecraft Charging? 2
1.3 How Does Spacecraft Charging Occur? 4
1.4 Capacitance Charging 5
1.5 Other Currents 6
1.6 Where Does Spacecraft Charging Occur? 6
1.7 Exercises 9
1.8 References 10
Chapter 2: The Spacecraft as a Langmuir Probe
2.1 Orbit-Limited Attraction 11
2.2 Current Collection in Spherical Geometry 12
2.3 Current Collection in Cylindrical Geometry 13
2.4 Current Collection in Plane Geometry 13
2.5 Remarks 14
2.6 Boltzmann's Repulsion Factor 14
2.7 Child-Langmuir Saturation Current 15
2.8 Exercises 16
2.9 References 17
Chapter 3: Secondary and Backscattered Electrons
3.1 Secondary Electron Emission 18
3.2 Backscattered Electrons 20
3.3 Total Contribution of Electron Emissions 20
3.4 Remarks 22
3.5 Dependence on Incident Angle 22
3.6 Remarks on Empirical Formulae 23
3.7 Exercises 23
3.8 References 24
Chapter 4: Spacecraft Charging in a Maxwellian Plasma
4.1 Velocity Distribution 25
4.2 Critical Temperature for the Onset of Spacecraft Charging: Physical Reasoning 26
4.3 Balance of Currents 26
4.4 Charging Level 29
4.5 Equation of Current Balance in the Orbit-Limited Regime 30
4.6 Comparison with Real Satellite Data 31
4.7 Exercises 32
4.8 References 33
Chapter 5: Spacecraft Charging in a Double Maxwellian Plasma
5.1 A General Theorem on Multiple Roots 35
5.2 Double Maxwellian Space Plasma 35
5.3 Triple-Root Situation of Spacecraft Potential 36
5.4 Physical Interpretation of Triple-Root Situation 40
5.5 Triple-Root Jump in Spacecraft Potential 41
5.6 Hysteresis 42
5.7 Triple-Root Spacecraft Charging Domains 42
5.8 Exercises 46
5.9 References 46
Chapter 6: Potential Wells and Barriers
6.1 Introduction 48
6.2 Formation of Potential Wells and Barriers 48
6.3 Effects of Potential Barriers on Electron or Ion Distribution Functions 51
6.4 Interpretation of Experimental Data 51
6.5 Double Maxwellian Distribution Formed by a Potential Barrier 52
6.6 Bootstrap Charging 53
6.7 Charging in Spacecraft Wakes 56
6.8 Exercises 58
6.9 References 58
Chapter 7: Spacecraft Charging in Sunlight
7.1 Photoelectron Current 60
7.2 Surface Reflectance 60
7.3 The Prominent Solar Spectral Line 62
7.4 Can Spacecraft Charging to Negative Voltages Occur in Sunlight? 62
7.5 Spacecraft Charging to Positive Potentials 63
7.6 The Photoemission Current at Negative Spacecraft Potentials 63
7.7 The Monopole-Dipole Potential 65
7.8 Fraction of Photoemission Current Trapped 67
7.9 Competition between Monopole and Dipole 68
7.10 Measurement of Spacecraft Potential in Sunlight 68
7.11 Exercises 69
7.12 References 70
Chapter 8: Space Tethers, Plasma Contactors, and Sheath Ionization
8.1 Lorentz Force 71
8.2 Tether Moving across Ambient Magnetic Field 71
8.3 Bare and Conducting Tether 73
8.4 Floating Potential of Plasma Contactor 75
8.5 Sheath Model 75
8.6 Sheath Ionization 77
8.7 Numerical Method for Sheath Ionization Model 79
8.8 Results of Sheath Ionization 80
8.9 Comparison of Theory with Space Experiment 81
8.10 Exercises 82
8.11 References 82
Chapter 9: Surface Charging Induced by Electron Beam Impact
9.1 Impact Energy of an Electron Beam 84
9.2 Electron Beam Impact on an Initially Uncharged Surface 85
9.3 Electron Impact on an Initially Negatively Charged Surface 85
9.4 Electron Impact on an Initially Positively Charged Surface 87
9.5 Summary 89
9.6 Limitation 89
9.7 Exercises 89
9.8 References 90
Chapter 10: Spacecraft Charging Induced by Electron Beam Emission
10.1 Current Balance without Beam Emission 91
10.2 Electron Beam Emission 92
10.3 Charging to Positive Potentials 93
10.4 Remarks 94
10.5 Exercises 95
10.6 References 96
Chapter 11: Supercharging
11.1 Charging Induced by Large Beam Current Emission 97
11.2 Supercharging 99
11.3 Physical Interpretation of Experimental Results 99
11.4 Surface Charging of Booms 100
11.5 Summary 101
11.6 Exercises 101
11.7 References 102
Chapter 12: Ion Beam Emission from Spacecraft
12.1 Active Control of Spacecraft Potential 103
12.2 Return of Ion Beam 105
12.3 Lower Limit of the Reduced Potential 106
12.4 Space Charge Effect 106
12.5 Charge Exchange in Charged Particle Beams 108
12.6 Chemical Reactions in Ion Beams 110
12.7 Ion Beam in Sunlight 110
12.8 Exercises 112
12.9 References 112
Chapter 13: Discharges on Spacecraft
13.1 Introduction 114
13.2 Location of Discharges on Spacecraft 114
13.3 Surface Discharge Scaling Law 116
13.4 Differential Charging 116
13.5 "Brush Fire" Discharge 117
13.6 Paschen and Non-Paschen Discharges 118
13.7 The Townsend Criterion 119
13.8 Remark on Threshold Voltage 121
13.9 Time Evolution of a Discharge 121
13.10 Laboratory Observations on Discharges 122
13.11 Discharges Initiated by Meteor or Debris Impacts 123
13.12 Exercises 124
13.13 References 124
Chapter 14: Energetic Particle Penetration into Matter
14.1 Introduction 126
14.2 High-Energy Charged Particle Penetration into Solids 126
14.3 Physics of High-Energy Charged Particle Penetration into Matter 127
14.4 The Bohr Model of Charged Particle Interaction 127
14.5 Stopping Power 129
14.6 The Bethe-Bloch Equation 129
14.7 Range and Penetration Distance 130
14.8 Approximate Penetration Depth Formula 132
14.9 Effects of Charged Particle Penetration 133
14.10 Effects on Astronauts 134
14.11 Research Questions in High-Energy Penetration of Charged Particles into Matter 134
14.12 Exercises 134
14.13 References 135
Chapter 15: Spacecraft Anomalies
15.1 Introduction 137
15.2 Space Anomalies due to Surface Charging 137
15.3 Energy of Surface Discharge 139
15.4 Correlation with Space Environment 140
15.5 Evidence of Deep Dielectric Charging on CRRES 140
15.6 Conclusive Evidence of Deep Dielectric Charging 141
15.7 Anomalies Observed on Twin Satellites in the Radiation Belts 142
15.8 Exercises 144
15.9 References 145
Chapter 16: Deep Dielectric Charging
16.1 Introduction 146
16.2 The Importance of Deep Dielectric Charging 146
16.3 High-Energy Electron and Ion Fluxes 147
16.4 Penetration of High-Energy Charges into Materials 148
16.5 Properties of Dielectrics 149
16.6 Observations Attributed to Deep Dielectric Charging 153
16.7 Avalanche Ionization in a High Electric Field 154
16.8 Related Questions and Related Mechanisms 155
16.9 The Mott Transition 156
16.10 The Poole-Frenkel High Electric Field Effect 158
16.11 Zener Breakdown 158
16.12 Electron Fluence 160
16.13 Critical Fluence for Deep Dielectric Charging 161
16.14 Charge Density with Leakage 161
16.15 A Remark on Spacecraft Anomalies 161
16.16 Effect of Electrons Deposited inside Electronics 162
16.17 Exercises 163
16.18 References 164
Chapter 17: Charging Mitigation Methods
17.1 Introduction 166
17.2 Sharp Spike Method 166
17.3 Hot Filament Emission Method 168
17.4 Conducting Grid Method 169
17.5 Partially Conducting Paint/Surface Method 169
17.6 High Secondary Electron Yield Method 169
17.7 Electron and Ion Emission Method 169
17.8 The DSCS Charge Control Experiment 171
17.9 Vaporization Method 172
17.10 Deep Dielectric Charging 172
17.11 Exercises 172
17.12 References 173
Chapter 18: Introduction to Meteors
18.1 Size Distribution 175
18.2 Meteor Showers 175
18.3 Meteor Velocity Limits 177
18.4 Nonshower Meteors 179
18.5 Debris 179
18.6 Meteor Composition 180
18.7 Exercises 180
18.8 References 180
Chapter 19: Meteor Impacts
19.1 Kinetic Energy of Meteoric Particles 182
19.2 Depth of Penetration 182
19.3 Mitigation of Meteoric Impacts 186
19.4 Meteor Shields 186
19.5 Impact Probability of Meteors 187
19.6 Perturbation of Angular Momentum 188
19.7 Secondary Electrons and Ions by Neutral Particle Impact 188
19.8 Plasma Generation by Neutral Particle Impact 188
19.9 Sudden Spacecraft Discharge Hazards 189
19.10 Summary 191
19.11 Exercises 191
19.12 References 191
Chapter 20: Neutral Gas Release
20.1 Ionization and Recombination 194
20.2 Critical Ionization Velocity 197
20.3 Neutral Beam Stripping 199
20.4 Exercises 201
20.5 References 201
Appendixes and Addenda
Appendix 1: Drift of Hot Electrons 205
Appendix 2: Transformation of Coordinates 214
Appendix 3: Normalization and Dimension of Maxwellian Distribution 215
Appendix 4: Flux Integrals 217
Appendix 5: Energy Distribution 219
Appendix 6: Sheath Engulfment 220
Appendix 7: PN Junctions 225
Appendix 8: Probability Function 229
Addendum 1: Computer Software for Spacecraft Charging Calculations 231
Addendum 2: Spacecraft Charging at Jupiter and Saturn 236
Addendum 3: Physical Constants and Conventions 240
Acknowledgments 243
Index 245