1 Introduction ................................................. 1
1.1 Overview of Role of Accelerators in Our Lives ........... 1
1.2 A Glance at the History of Accelerator Development ...... 2
1.2.1 Development of Electrostatic Accelerators ........ 4
1.2.2 Development of Circular Accelerators ............. 6
1.2.3 Development of RF Linear Accelerators ............ 8
1.3 Cancer Radiation Therapy ............................... 10
1.4 Market for Industrial Accelerators ..................... 11
1.4.1 Producing Medical Radioisotopes for Imaging
and Nuclear Medicine ............................ 12
1.4.2 Electron Beam Sterilization of Medical
Disposables and Food Processing ................. 12
1.4.3 Nondestructive Testing (NDT) .................... 12
1.4.4 Ion Implantation in Semiconductor Chip
Fabrication ..................................... 13
1.4.5 Processing of Polymers .......................... 13
1.4.6 Security and Inspection Applications ............ 13
References .................................................. 13
2 Linac Basic Concepts and Constituents ....................... 15
2.1 Fundamental Concepts and Definitions ................... 16
2.2 Coupled Accelerator Cavities ........................... 21
2.3 Linac's Different Configurations ....................... 27
2.3.1 Standing-Wave Linacs ............................ 27
2.3.2 TW Linacs ....................................... 32
2.3.3 Bunching Mechanism .............................. 34
2.4 Electron Gun Operation ................................. 35
2.5 X-Ray Generation and Target Design ..................... 37
2.5.1 Mechanism of Conversion ......................... 38
2.5.2 X-Ray Target Design Requirements ................ 38
2.5.3 Target Design Approaches ........................ 39
References .................................................. 40
3 Linac Supporting System ..................................... 43
3.1 Introduction—The Linac as a Source for Electron and
X-Ray Beams ............................................ 43
3.2 Linac Auxiliary Systems ................................ 45
3.2.1 Linac Vacuum System ............................. 45
3.2.2 RF Vacuum Window ................................ 46
3.2.3 Linac Water-Cooling System ...................... 48
3.3 Radio Frequency (RF) System ............................ 49
3.3.1 RF High-Power Sources ........................... 50
3.3.2 RF Power Transmission Subsystems ................ 56
References .................................................. 60
4 Manufacturing Techniques of Accelerators .................... 61
4.1 Overview of Manufacturing Processes .................... 61
4.2 Material Requirements .................................. 63
4.3 Cavity Machining ....................................... 65
4.4 Chemical Cleaning ...................................... 65
4.5 Assembly and Bonding Techniques ........................ 66
4.5.1 Brazing ......................................... 66
4.5.2 Diffusion Bonding ............................... 70
4.6 Tuning of Linacs ....................................... 71
4.7 Thermal Outgasing (Bake-Out) ........................... 73
4.8 Electron Gun Activation ................................ 74
4.9 High-Power RE Conditioning ............................. 76
4.10 Linac's Beam Tests and Test Bunkers .................... 78
4.11 Common Manufacturing Issues and Imperfections .......... 80
4.12 Quality Systems in Linac Manufacturing ................. 80
4.12.1 Examples of QC and QA Measures .................. 81
4.12.2 Examples of Statistical Process Control ......... 84
4.13 Guidelines for Linac Buyers and Users .................. 86
References .................................................. 88
5 Role of Linear Accelerators in Cancer Radiation Therapy ..... 91
5.1 Basic Radiation Therapy Concepts and Definitions ....... 91
5.2 Radionuclides-Based Radiation Therapy .................. 95
5.2.1 Brachytherapy ................................... 95
5.2.2 Cobalt Teletherapy .............................. 95
5.3 Accelerator-Based Radiation Therapy .................... 97
5.4 The Medical Linac Requirements ......................... 98
5.5 Clinical Use of Linacs in Radiation Therapy ........... 100
5.5.1 Clinical Requirements .......................... 100
5.5.2 Treatment Planning and Simulation .............. 101
5.5.3 Dose Fractionation ............................. 101
5.5.4 Rotational Therapy ............................. 103
5.6 Conformal Radiation Therapy ........................... 104
5.6.1 Multileaf Collimators (MLCs) ................... 105
5.6.2 Intensity-Modulated Radiation Therapy (IMRT) ... 106
5.6.3 Adaptive Radiation Therapy (ART) ............... 108
5.7 Image-Guided Radiation Therapy (IGRT) ................. 109
5.7.1 Need for IGRT and Treatment Verification ....... 109
5.7.2 Portal Films ................................... 110
5.7.3 Electronic Portal Imaging Devices .............. 110
5.7.4 Tomotherapy .................................... 112
5.7.5 Robotic Radiosurgery: CyberKnife® .............. 114
5.8 Stereotactic Radiosurgery ............................. 115
5.8.1 Gamma Knife ™ Radiosurgery ..................... 115
5.9 Intraoperative Radiation Therapy ...................... 117
5.10 Concluding Remarks .................................... 118
References ................................................. 119
6 Accelerator-Based Industrial Applications .................. 121
6.1 Use of Accelerators in Material Processing ............ 121
6.1.1 Electron Beam Current and Energy Requirements .. 122
6.1.2 Main Applications for Polymer EB
Cross-Linking .................................. 123
6.1.3 Industrial Material Processing Using X-Ray
Radiation ...................................... 126
6.2 Sterilization of Medical Products and Food
Irradiation ........................................... 127
6.2.1 Medical Product Sterilization .................. 127
6.2.2 Electron Beam Food Processing by Irradiation ... 129
6.2.3 Mechanism of Killing Pathogens ................. 130
6.3 Environmental Applications of Accelerators ............ 131
6.3.1 Wastewater Treatment ........................... 131
6.3.2 EB Treatment of Flue Gases—Reduction of Acid
Rain ........................................... 133
6.4 Nondestructive Testing ................................ 135
6.5 Security and Inspection Applications .................. 137
6.5.1 Scanning Units ................................. 138
6.5.2 Recent Advancements in Cargo Inspection ........ 140
6.6 Ion Implantation in Semiconductor Chip Fabrication .... 143
6.6.1 Concept of Operation ........................... 143
6.7 Concluding Remarks .................................... 144
References ................................................. 145
7 Large Accelerators ......................................... 149
7.1 Large Accelerator Facilities for High-Energy Physics .. 149
7.1.1 Linear Colliders ............................... 150
7.1.2 Circular Colliders ............................. 151
7.1.3 Use of Superconductivity in Large
Accelerators ................................... 154
7.2 Synchrotrons Sources .................................. 157
7.2.1 Synchrotron Storage Rings ...................... 157
7.2.2 Wigglers and Undulators ........................ 160
7.2.3 Examples of Synchrotron Radiation
Applications ................................... 161
7.3 Cancer Particle Therapy ............................... 163
7.3.1 Advantages of Particle Therapy ................. 164
7.3.2 Particle Therapy Circular Accelerators ......... 166
References ................................................. 169
8 Recent Developments and Future Trends in Accelerator
Technology ................................................. 173
8.1 Free-Electron Laser ................................... 174
8.2 Accelerator-Based Neutron Sources ..................... 176
8.2.1 Neutron Spallation Sources ..................... 176
8.2.2 The Spallation Neutron Source (SNS) ............ 177
8.3 Plasma-Based Accelerators ............................. 178
8.3.1 Basic Concept of PWFA .......................... 179
8.4 Dielectric Wall Accelerators .......................... 180
8.4.1 Basic Concept of DWA ........................... 181
8.5 Concluding Remarks .................................... 183
References ................................................. 184
Glossary ................................................... 187
About the Author ........................................... 193
Index ...................................................... 195
| 
