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Table of Contents
Abstract... v
Introduction to my work ... vi
1. ILC – the International Linear Collider... 1
1. Introduction ... 1
2. Superconducting technology (briefly), the accelerating gradient and luminosity :... 5
3. Benefits from Accelerators and High-energy Physics... 6
4. Benefits from past high-energy physics R&D... 6
5. ILC technology sectors and impact in other sciences: ... 9
6. Simply Conclusions:... 12
2 Accelerator and Cavity Physics ... 14
2.0 Introduction ... 14
2.1 Circular accelerators problems ... 16
2.2 How a linac works: ... 17
2.3 Acceleration - Cavity theory... 22
2.4 Basics of RF superconductivity and SRF materials ... 28
2.5 Possible problems for the SRF cavities ... 31
2.6 SRF cavities Tuning ... 33
3 The Cavity Tuning Machine... 34
3.0 The Cavity Tuning Machine project... 34
3.1 Functional Overview ... 34
3.2 Key control system design requirements... 36
3.3 Control devices electrical interface ... 37
3.4 Control rack ... 38
3.5 Personnel safety... 39
3.6 Operator station ... 39
3.7 RF measurements ... 40
3.7.1 Network Analyzer... 40
3.7.2 Field Probe calibration ... 41
3.7.3 Spectrum Measurements... 41
3.7.4 Field Flatness Measurement ... 42
3.7.5 Field Amplitudes Measurement for all modal frequencies ... 44
3.8 Description of the Electrical tuning model... 44
3.9 Brief description of the Eccentricity measurements... 46
3.10 Brief description of the Cavity alignment measurement ... 47
3.11 Cavity transport control ... 47
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4 Eccentricity Measurement ... 50
4.0 Introduction ... 50
4.1 Hardware and First Technique ... 50
4.2 Estimation of Cell Centers... 54
4.3 End-Reference Flange Perpendicularity Measurement ... 58
4.4 Mechanical Issues (Known in February):... 63
4.5 Dummy cavity Eccentricity measurement... 64
4.5.1 MATLAB Analysis – Old EMD Bar... 65
4.5.2 MATLAB Analysis – New EMD Bar ... 93
4.5.3 Analysis of two different measurements ... 101
4.5.4 Conclusions ... 103
4.5.5 Comparison between LabVIEW results and Matlab ... 105
5 Eccentricity Correction... 110
5.1 Cavity Alignment Measurement... 110
5.2 Laser Pre-test ... 112
5.2.1 Bump cut-off program modified... 123
5.3 Eccentricity correction – Laser movement ... 127
5.3.1 Why we need alignment correction ... 129
5.3.2 How it can be done ... 130
5.3.3 Algorithm ... 130
5.4 Mechanical Model ... 133
5.4.1 Tuning of DESY ILC Z142 ... 147
5.4.2 Tuning of FNAL ILC TB9RI024 ... 155
5.5 Pre-tuning ... 163
5.6 Quick check of the necessity of the tuning... 166
6 LabVIEW programs ... 167
6.1 Automatic Cavity Tuning Machine Control System ... 167
6.2 Architecture Overview ... 168
6.3 Plug-in Functionality ... 169
6.4 Data Saving ... 173
6.5 Eccentricity LabVIEW program - Plugin... 174
6.5.1 Raw Sensor Data: ... 175
6.5.2 Eccentricity Results: ... 176
6.5.3 Running Status: ... 176
6.5.4 Reference Flange Angles:... 177
6.6 Alignment LabVIEW program - Plugin ... 179
6.7 Tuning Front Panel - Plug-in ... 196
6.8 Results ... 199
