1. STABILISATION AND PRECISION POINTING QUADRUPOLE MAGNETS IN THE COMPACT LINEAR COLLIDER S. Janssens, P. Fernandez Carmona, K. Artoos, C. Collette *, M. Esposito, M. Guinchard, C. Hauviller, A. Kuzmin, R. Leuxe, R. Morón Ballester The research leading to these results has received funding from the European Commission under the FP7 Research Infrastructures project EuCARD * ULB

2. Scope: History 2 > Collider History Energy increasing Heavy Hadron collider at energy frontier Light Lepton collider for precision physics > LHC online now > e-/e+ storage ring excluded by synchrotron Radiation > Consensus to built lin. lepton collider with E cm > 500 GeV to complement LHC physics (European strategy for particle physics by CERN Council)

3. Compact Linear Collider (CLIC) 3  Novel 2 beam concept  100 MV/m  1 chance for collisions  Vert. Beam size 1nm at ip  Hor. Beam size 40 nm at ip

4. Scope: CLIC 4 The main beam accelerator Accelerating structure: To accelerate the beam Quadrupole magnets: Mass 100-400 kg Length 500-2000 mm 200 T/m To focus the beam after accelerating structures Accelerating structure

5. Scope: CLIC 5 Courtesy J. Pfingstner

6. Scope: CLIC 6 Courtesy J. Pfingstner Method 1: Linac feedback 4. Complications: BPM noise: measurement cannot be fully trusted System sensitivity: beam is sensitive to the shape of the misalignment 5. Limitations: Beam arrives only every 20ms According to Shannon’s sampling theorem: only frequencies till f N = 25Hz resolvable Digital feedback is only effective up to approx. f N /10, due to stability reasons => high frequency ground motion still to strong => Second system is necessary 1. Purpose: Reduce the emittance growth along the accelerator 2. Strategy: Measure the beam oscillations Steer the beam back into the centre of the BPMs. Note: This also reduces beam-beam offset (for low frequencies). 3. Hardware: Sensors: 2122 BPMs Kicker magnets Distribution system (very high demands on the control system) One central controller (computer)

7. Scope: CLIC 7 Method 2: quadrupole stabilisation/vibration isolation 1.Purpose: Reduce the emittance growth from high frequencies 2.Issues: - Ground motion - External forces 3. Strategy: -Local strategy (each quadrupole stab. independent) -On top of an alignment stage Alignment stage: Cam system Locked when beam on 3 mm range Slow motion > weeks

8. Stabilisation Requirements Stability (magnetic axis): Nano-positioning 3992 CLIC Main Beam Quadrupoles: 8 Type 4: 2m, 400 kgType 1: 0.5 m, 100 kg A. Samoshkin Main beam quadrupoles Final Focus Vertical 1.5 nm > 1 Hz Vertical 0.2 nm > 4 Hz Lateral 5 nm > 1 Hz Lateral 5 nm > 4 Hz  Ground motion  External forces  Flexibility of magnet

9. Additional objectives 9 « Nano-positioning» for method 1 Modify position quadrupole in between pulses (~ 5 ms) Range ± 5 μ m, increments 10 to 50 nm, precision ± 1nm  In addition/alternative dipole correctors  Increases time to next realignment Additional requirements:  Compatibility alignment  Transportability  Available space  High radiation  Stray magnetic fields

10. Characterisation ground vibration 10 Cultural noise -Human activity -Incoherent -Highly variable Earth noise - Coherent Micro seismic peak -> Sea waves Reduced by Method 1: Beam based feedback Deeper tunnel 2-5 nm int. RMS Reduction needed <100 Hz Method 2: vibration isolation

11. Characterisation ground vibration 11 There are various laws and they are adapted for specific locations Proposed law used by J. Pfingstner for CLIC For low frequency adjusted random walk Higher frequency: sum of peaks D i form of the peak a i height of the peak d i position of the peak U i determines wavelength composition wavelength

12. Characterisation ground vibration 12 M. Guinchard Link C. Collette

13. Vibration Isolation Strategies 13 Earth quake protection Big civil engineering projects Chip manufacturing (Lithography) Big Physics projects Daily life Big Physics projects Space

14. Passive Isolation Strategies Both can be referred to as transfer functions 14 Spring mass system TermPhysical meaning SymbolUnit Transmissibilityx/wT wx [-] Compliancex/FaT Fax [m/N] TermSym.Unit massm[kg] stiffnessk[N/m] Dampingc[N/(m/s)] Induced forceFa[N] Ground vibrationsw[m] Quadrupole vibrationsx[m]

15. Passive Isolation Strategies Isolation 15 Passive Isolation Car suspension Vibration reduction: Payload ↔ ground Transmissibility

16. Passive Isolation Strategies  Trade off between magnification at resonance and isolation Isolation 16 Passive Isolation Transmissibility

17. 17 Passive Isolation Strategies 1909: US 970,368 Dynamic vibration absorber  Spurious peaks  Difficult to make an efficient compact design  Either damping, or isolation for narrow band excitation Transmissibility

18. 18 Optimal parameters Relaxation Passive Isolation Strategies Relaxation isolator Transmissibility Not easy to make Sensitive to errors in parameters

19. Passive Isolation Strategies 19 Effect of support stiffness [m/N] Soft support :  Improves the isolation  Make the payload more sensitive to external forces Fa Transmissibility Compliance Watercooling Accoustics Ventilation

20. Active Isolation Strategies Add virtual mass Feedback control principle

21. Sky-hook damper (D.C. Karnopp, 1969 ) Active Isolation Strategies Feedback control principle

22. Position feedback would be great !  How to do it ? Active Isolation Strategies Feedback control principle

23. 23 How to measure it? Simple reference mass (ex. Geophone): -Small mass -Soft suspension -Measure relative displacement/velocity -Above resonance=>good estimate of w

24. 24 Active Isolation Strategies Inertial reference on payload (TNO) Inertial reference on ground (AIMS) Two stages (TMC) Very soft suspension Relative measurement with reference mass Stiff suspension with softer intermediate part Relative measurement between intermediate mass and payload

25. 25 Active Isolation Strategies >Not stiff enough for nm stability a b c m =100 kg compliance Ref. on top interesting for w rejection Ref. below interesting for disturbance rejection a a b b

26. 26 Active Isolation Strategies >Stiff enough >Unwanted additional resonance a b c m =100 kg compliance Ref. on top interesting for w rejection Ref. below interesting for disturbance rejection c c

27. Practical application Very Soft (1 Hz) Stiff (200 Hz) Pneumatic actuator Hydraulic actuator Electromagnetic in parallel with a spring + Broadband isolation - Stiffness too low - Noisy Piezo actuator in series with soft element (rubber) + Passive isolation at high freq. + Stable - Additional resonance - Low compatibility with AE Soft (20 Hz) Piezoelectric actuator in series with stiff element (flexible joint) + Extremely robust to forces + Fully compatible with AE + Comply with requirements -Strong coupling (stability) 27 COMPARISON k~0.01 N/µm k~1 N/µm Piezo k~100-500 N/µm

28. Simplified modelling 28 Piezo actuator with reference on top Tested the effect of a flexible magnet Tested the effect of the pre-alignment system Tested the effect of a flexible joint->Danger!! Not collocated => Make collocated or have the resonance out of controller bandwidth

29. Simplified modelling 29 Geophone => Sensitive to slewrate of piezo actuator/Not commercially available collocated

30. Practical application 30 Researched Configurations Final 2D design + Stiff + Cost effective - Only 2 d.o.f. control

31. 31 Controller Hardware ~50 km Control Centre x 3992 Main Beam Quadrupoles Controller electronics

32. 32 Design constraints  Inputs:  Resolution 2 µV  Dynamic range 60 dB  Bandwidth 0.1-100 Hz  Output:  Dynamic range 140 dB  Resistance to radiation  Shielding, location, design  Cost (~4000 magnets to be stabilized)  Power restrictions (cooling) MB 9 GeV Courtesy S. Mallows

33. 33 Design constraints II  Latency (stability limit)  Need for local control  Electromagnetic compatibility  Shielded + twisted pairs  Short sensor cables ComponentDelay ADC8 µs Electro-optic transducer 100 ns Optic fiber transmission 5 µs/Km Opto-electric transducer 120 ns DAC3 µs Actuator (20nm single step) 1 µs Typical catalog delay values for the components Control loop delay Stabilization performance 43 μ s 100% 80 μ s 90% 90 μ s 80% 100 μ s 60% 130 μ s30% Local controller

34. 34 Evolution of electronics 1. General purpose National Instruments PXI  ADC/DAC interfaces  Digital processing  Fast developing, Flexibility  Expensive (10k$), no accelerator environment  Fixed latency 43µs (adds a variable phase) 2. Custom built analogue controller  Latency reduced to small phase shift  Low cost <100$  40x Power reduction  No flexibility General purpose PXI Analogue controller

35.  Advantages  Flexibility  Easy reuse of IP  Noise only added at ADC and DAC  Disadvantages  Single events upsets  Higher latency  Advantages  Minimum latency  Simplicity  Less radiation effects expected  Disadvantages  Fixed configuration 35 Digital implementationAnalogue implementation Hybrid controller

36. 36 Controller electronics: Hybrid 2 analogue chains + positioning offset Local electronics ADCs digitize signals For remote monitoring Communication to remote control center with optical fiber Configurable parameters Gain Feedforward Gain Feedback Lag pole and zero frequencies Lead pole and zero frequencies Output offset (positioning) Feedforward low pass filter frequency SPI

37. 37 Hybrid controller schematic Digital

38. 38 Radiation levels expected Simulations Courtesy S. Mallows  1 MeV-neutron Equivalent Fluence  Cumulative Effects  Lattice Displacement  (non ionizing energy losses)  Absorbed dose  The Total Ionizing Dose (TID)  Estimated for 180 days  20 MeV Hadron Fluence  Single Event Effects (SEEs)  All particles with E>20 MeV cm -2 Gy All values correspond to medium values according to CERN ´s R2E Study Group classification

39. 39 Radiation considerations Courtesy S. Mallows  Analogue part:  Single events: Little effect. Quick bumps Self restoring of normal operation  Cumulative effects: Capacitors and resistors: Literature tests OK Semiconductors: Performance loss Design with security margin + configurability Commercial radiation amplifiers available For example TI LM124-SP certified for 50 kRad, would fail after 25 years of CLIC equivalent dose

40. 40 Radiation considerations Courtesy S. Mallows  Digital part:  SEE: Digital potentiometers sensitive (FLASH memory) Detectable as vibration peak. Reconfigure component(~10 ms)  SEE: Other digital components: monitoring To be done: mitigation using triplication with voters in FPGAs, or use of qualified components. ELMB generic board is under evaluation.  Cumulative effects: To be retested Most potentially harmful.

41. 41 Testbenches used 1 d.o.f. (membrane) 2 d.o.f. (xy-guide) Type 1 Water-cooled magnet

42. 42 Testbenches used Testing of control theory Same mass to stiffness ratio as final design Seismometer feedback Seismometer feedback and feedforward

43. 43 Testbenches used Testing of control theory Seismometer feedback and feedforward (similar results) Testing of mechanical two leg proposal with shear pins Same actuators and mass as final design Positioning tests with multiple sensor crosscheck (vertical while moving laterally) nm hard to measure Good repeatability Interferometer drift =>what best for position sensor feedback?

44. Comparison sensors 44 SensorResolutionMain +Main - Actuator sensor0.15 nmNo separate assemblyResolution No direct measurement of magnet movement Capacitive gauge0.10 nmGauge radiation hardMounting tolerances Gain change w.  Orthogonal coupling Interferometer10 pmAccuracy at freq.> 10 HzCost Mounting tolerance Sensitive to air flow Orthogonal coupling Optical ruler0.5*-1 nmCost 1% orthogonal coupling Mounting tolerance Small temperature drift Possible absolute sensor Rad hardness sensor Limited velocity Resolution Seismometer (after integration)< pm at higher frequenciesFor cross calibration

45. X-y positioning: Future Study precision, accuracy and resolution 45 Optical rulers: Better precision required (0.25 nm): demonstrated with optical rulers Tests in a temperature unstable environment will be made (ISR re installation) Absolute position sensor: Possibility to go back to predefined point calibrated within 10 -8 m

46. X-y Positioning: roll 46 1&2 Parasitic roll 2 legs 3 d.o.f. > parasitic roll Measured with 3-beam interferometer ~3 μm lateral movement > ~7 μ rad rotation Early simulations suggest~100 μ rad/0.5% luminosity loss (J. Pfingstner)

47. 47 0.5 m, 100 kg magnet Water cooling 4 l/min With magnetic field on FigureValue R.m.s @ 1Hz magnet0.5 nm R.m.s @ 1Hz ground6.3 nm R.m.s. attenuation ratio~13 R.m.s @ 1Hz objective1.5 nm Stabilization on Type 1 magnet

48. Integrated luminosity simulations 48 No stabilization68% luminosity loss Seismometer FB maximum gain13% Seismometer FB medium gain 6% (reduced peaks @ 0.1 and 75 Hz) Seismometer FB maximum gain +FF4% Inertial reference mass11% Inertial reference. mass. + HP filter3% Courtesy J. Snuverink et al. Commercial Seismometer Custom Inertial Reference mass

49. Full type 1 and Type 4 prototype 49 Type 1 (100 kg) prototype finished (re)construction Type 4 (400 kg) prototype in produced First tests Scheduled for December 2014 Manpower reduced to 1.5

50. Conclusions 50 A stiff piezo actuator was chosen to cope with external forces on the system to the nano metre level. It was demonstrated with models and in a test bench that it is technically feasible to stabilise a mass better than the required level at 1Hz. A concept design of the stabilisation support based on the validated actuator pair with flexural has been constructed and tested succesfully.

51. Future work 51 Test full Type 1 (december 2014) Redesign the control board for collaboration with interface cards for CLIC + reduce size. Add relative position control to eliminate drift Phd student is working at TU Delft on extending the range of actuator and guiding system to eliminate the alignment stage. Phd student is researching new sensor for collocated control.

52. Journal Publications 52  [1] COLLETTE C., ARTOOS K., KUZMIN A., JANSSENS S., SYLTE M., GUINCHARD M. and HAUVILLER C., Active quadrupole stabilization for future linear particle colliders, Nuclear instruments and methods in physics research section A, vol.621 (1-3) pp.71-78 (2010).  [2] COLLETTE C., ARTOOS K., GUINCHARD M. and HAUVILLER C., Seismic response of linear accelerators, Physical reviews special topics – accelerators and beams vol.13 pp. 072801 (2010).  [3] ARTOOS K., COLLETTE C., FERNANDEZ-CARMONA P., GUINCHARD M., HAUVILLER C., JANSSENS S. KUZMIN A., LACKNER F., LEUXE R. and SLAATHAUG A., Stabilization and fine positioning to the nanometre level of the CLIC Main beam quadrupoles, accepted in Physical reviews special topics – accelerators and beams (submitted in 2010).  [4] COLLETTE C., FERNANDEZ-CARMONA P., JANSSENS S., ARTOOS K., GUINCHARD M., HAUVILLER C., Inertial sensors for low frequency seismic vibration measurement, Physics of the Earth and Planetary Interiors (submitted in 2011).  [5] COLLETTE C., FERNANDEZ-CARMONA P., JANSSENS S., ARTOOS K., GUINCHARD M., HAUVILLER C., Nano-Motion Control of Heavy Quadrupoles for Future Particle Colliders: An Experimental Validation, Nuclear instruments and methods in physics research section A (submitted in 2011).

53. Scope: CLIC 53 Courtesy J. Pfingstner

54. Stability 54 S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011 11 poles! Sources of instability:  Filters  Sensor/Actuator  Delay

55. Theoretical performance 55 S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011 Transmissibility

56. MULTIPLE d.o.f. 56 Modeling multiple d.o.f. in parts: get firm understanding of interactions between mechanics and controller Unstable S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011 Stable 4 d.o.f. Give parameters for mechanical system =>xy-guidance

57. MULTIPLE d.o.f. 57 S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011 To be done: Add alignment

58. Strategy chosen 58 S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011  Stiff Active structure  Flexural hinges  Seismometers (Feedforward, Feedback)  At least four d.o.f.  Parallel structure  xy-guidance  Block longitudinal motion  Block roll  0.1 nm resolution vertically

59. Implementation of electronics Controller Hardware 59

60. 60 Controller Hardware ~50 km Control Centre x 3992 Main Beam Quadrupoles Controller electronics S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

61. 61 Design constraints  Inputs:  Resolution 2 µV  Dynamic range 60 dB  Bandwidth 0.1-100 Hz  Output:  Dynamic range 140 dB  Resistance to radiation  Shielding, location, design  Cost (~4000 magnets to be stabilized)  Power restrictions (cooling) MB 9 GeV Courtesy S. Mallows S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

62. 62 Design constraints II  Latency (stability limit)  Need for local control  Electromagnetic compatibility  Shielded + twisted pairs  Short sensor cables ComponentDelay ADC8 µs Electro-optic transducer 100 ns Optic fiber transmission 5 µs/Km Opto-electric transducer 120 ns DAC3 µs Actuator (20nm single step) 1 µs Typical catalog delay values for the components Control loop delay Stabilization performance 43 μ s 100% 80 μ s 90% 90 μ s 80% 100 μ s 60% 130 μ s30% Local controller S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

63. 63 Sensors and cabling EMC  Sensor cables ~5m long : Strong noise source  BW <1KHz. Main noise contribution= Near field Electric field rejected with shielding Magnetic field. Shielding little effective Coaxial cable only shields f>10 KHz Twisted pair only solution  Improve sensor’s power supply quality Linear, low ripple the best Regular switched industrial supplies introduce spurious noise H field I I I I Signal DC supply S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

64.  Influence of power supply  Influence of cables 64 EMC and supply effects S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

65. Error budgeting: Electronic noise sources 65 S. Janssens, CLIC Meeting, Geneva 28 January 2011 S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

66. 66 Evolution of electronics 1. General purpose National Instruments PXI  ADC/DAC interfaces  Digital processing  Fast developing, Flexibility  Expensive (10k$), no accelerator environment  Fixed latency 43µs (adds a variable phase) 2. Custom built analogue controller  Latency reduced to small phase shift  Low cost <100$  40x Power reduction  No flexibility General purpose PXI S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011 Analogue controller

67.  Advantages  Flexibility  Easy reuse of IP  Noise only added at ADC and DAC  Disadvantages  Single events upsets  Higher latency  Advantages  Minimum latency  Simplicity  Less radiation effects expected  Disadvantages  Fixed configuration 67 Digital implementationAnalogue implementation Hybrid controller S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

68. 68 Controller electronics: Hybrid 2 analogue chains + positioning offset Local electronics ADCs digitize signals For remote monitoring Communication to remote control center with optical fiber S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011 Configurable parameters Gain Feedforward Gain Feedback Lag pole and zero frequencies Lead pole and zero frequencies Output offset (positioning) Feedforward low pass filter frequency SPI

69. 69 Hybrid controller schematic Digital S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

70. 70 Radiation levels expected Simulations Courtesy S. Mallows  1 MeV-neutron Equivalent Fluence  Cumulative Effects  Lattice Displacement  (non ionizing energy losses)  Absorbed dose  The Total Ionizing Dose (TID)  Estimated for 180 days  20 MeV Hadron Fluence  Single Event Effects (SEEs)  All particles with E>20 MeV cm -2 Gy All values correspond to medium values according to CERN ´s R2E Study Group classification S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

71. 71 Radiation considerations Courtesy S. Mallows  Analogue part:  Single events: Little effect. Quick bumps Self restoring of normal operation  Cumulative effects: Capacitors and resistors: Literature tests OK Semiconductors: Performance loss Design with security margin + configurability Commercial radiation amplifiers available For example TI LM124-SP certified for 50 kRad, would fail after 25 years of CLIC equivalent dose S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

72. 72 Radiation considerations Courtesy S. Mallows  Digital part:  SEE: Digital potentiometers sensitive (FLASH memory) Detectable as vibration peak. Reconfigure component(~10 ms)  SEE: Other digital components: monitoring error To be done: mitigation using triplication with voters in FPGAs, or use of qualified components. ELMB generic board is under evaluation.  Cumulative effects: To be tested soon Most potentially harmful. S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

73. 73 Testbenches used 1 d.o.f. (membrane) 2 d.o.f. (tripod) Type 1 Water-cooled magnet S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

74. 74 Stabilization results Wide BW High attenuation S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011 Transmissibility: X/W

75. 75 Stabilization results 5x lower than requirements 1&2 Objective reached on all testbenches 0.3 nm on Membrane, 0.5 nm on Tripod, 0.5 nm on Type 1 2 nm S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

76. 76 Long Term Stability  Temperature stable within 0.5 degrees Test with temperature change in preparation Objective achieved S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

77. 0.5 nm Ratio:13 0.7 nm Ratio:9 0.6 nm Ratio:5 0.3 nm Ratio:6 0.8 nm Ratio:2.5 3.5 nm Ratio:1.5 1.2 nm Ratio:1.8 77 Stabilization milestones Membrane July 2009Tripod June 2010Type 1 September 2011 General purpose PXI Analogue controller Hybrid controller Objective 1.5 nm r.m.s. Custom cables and shielding FB + FF Analogue = less latency Remote configurable Board optimization Feedback S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

78. 78 0.5 m, 100 kg magnet Water cooling 4 l/min With magnetic field on FigureValue R.m.s @ 1Hz magnet0.5 nm R.m.s @ 1Hz ground6.3 nm R.m.s. attenuation ratio~13 R.m.s @ 1Hz objective1.5 nm Stabilization on Type 1 magnet S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

79. Integrated luminosity simulations 79 No stabilization68% luminosity loss Seismometer FB maximum gain13% Seismometer FB medium gain 6% (reduced peaks @ 0.1 and 75 Hz) Seismometer FB maximum gain +FF7% Inertial reference mass11% Inertial reference. mass. + HP filter3% Courtesy J. Snuverink et al. Commercial Seismometer Custom Inertial Reference mass S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

80. Positioning in 2 d.o.f. 80 S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011 80 Measured x-y capacitive 10 nm Horizontal motion Vertical motion 150 nm

81.  Optimization of controller and mechanics  Development of new sensors  Integration with alignment system  Implementation of custom digital slow control  Increase range for positioning  Development of small series production  Research  Find optimal components  Simulate effects of SEE on vibrations and luminosity  Evaluation of standards: Worldfip, GBT, ELMB,…  Test prototypes under radiation  At CERN: CNGS / CTF3 81 Functionality and prototypingRadiation Future work S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

82. 82 Conclusions S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

83. Conclusions 83 C. Collette, LCWS 2011, Granada, Spain Five R&D themes in 2011: 1.Performance increase → Reach requirements from higher background vibrations → Increase resolution (Final focus) 2.Compatibility with environment → Radiation, magnetic field 3.Cost optimization → Standardize and optimize components, decrease number of components, simplify mounting procedures,… 4.Overall system analysis → Interaction with the beam-based orbit and IP feedback to optimise luminosity Integration with other CLIC components → Adapt to changing requirements 5.Pre-industrialization → Ability to build for large quantities

84. Publications 84  COLLETTE C., ARTOOS K., KUZMIN A., SYLTE M., GUINCHARD M. and HAUVILLER C., Active quadrupole stabilization for future linear particle colliders, Nuclear instruments and methods in physics research section A, vol.621 (1-3) pp.71-78 (2010).  COLLETTE C., ARTOOS K., GUINCHARD M. and HAUVILLER C., Seismic response of linear accelerators, Physical reviews special topics – accelerators and beams vol.13 pp. 072801 (2010).  ARTOOS K., COLLETTE C., GUINCHARD M., JANSSENS S., KUZMIN A. and HAUVILLER C., Compatibility and integration of a CLIC quadrupole nano-stabilization and positioning system in a large accelerator environment, IEEE International Particle Accelerator Conference IPAC10, 23-25 May 2010 (Kyoto, Japan).  ARTOOS K., COLLETTE C., GUINCHARD M., JANSSENS S., LACKNER F. and HAUVILLER C., Stabilisation and fine positioning to the nanometer level of the CLIC Main beam quadrupoles, IEEE International Particle Accelerator Conference IPAC10, 23-25 May 2010 (Kyoto, Japan).  COLLETTE C., ARTOOS K., JANSSENS S. and HAUVILLER C., Hard mounts for quadrupole nano-positioning in a linear collider, 12th International Conference on New Actuators ACTUATOR2010, 14-16 May 2010 (Bremen, Germany). S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

85. Publications 85  COLLETTE C., JANSSENS S., ARTOOS K. and HAUVILLER C., Active vibration isolation of high precision machine (keynote lecture), 6th International Conference on Mechanical Engineering Design of Synchrotron Radiation Equipment and Instrumentation (MEDSI 2010), 14 July 2010 (Oxford, United Kingdom).  COLLETTE C., JANSSENS S., ARTOOS K., GUINCHARD M. and HAUVILLER C., CLIC quadrupole stabilization and nano-positioning, International Conference on Noise and Vibration Engineering (ISMA2010), 20-22 September 2010 (Leuven, Belgique).  JANSSENS S., COLLETTE C., ARTOOS K., GUINCHARD M. and HAUVILLER C., A sensitiviy analysis for the stabilization of the CLIC main beam quadrupoles, Conference on Uncertainty in Structural Dynamics, 20-22 September 2010 (Leuven, Belgique).  FERNANDEZ-CARMONA P., COLLETTE C., JANSSENS S., ARTOOS K., GUINCHARD M., KUZMIN A., SLAATHAUG A., HAUVILLER C., Study of the electronics architecture for the mechanical stabilization of the quadrupoles of the CLIC linear accelerator, Topical Workshop on Electronics for Particle Physics TWEPP 2010, 20-24 September 2010 (Aachen, Germany). S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

86. Spares S. Janssens, CLIC Meeting, Geneva 28 January 2011 86

87.  Changed according to vibration changes  Digital potentiometers used  Controlled via a serial peripheral interface SPI port  Change induces vibrations:  Signal crosstalk  Resistor settling time  No change while beam on  Includes registers and memories sensitive to SEU  Detectable and non permanent 87 Configurable parameters Gain Feedforward Gain Feedback Lag pole and zero frequencies Lead pole and zero frequencies Output offset (positioning) Feedforward low pass filter frequency S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

88. Radiation: tantalum capacitors  tantalum capacitors were exposed to fluence of 21014 63MeV protons at the UC-Davis cyclotron. The value of the capacitors and the breakdown voltages were not measurably altered at this radiation level.  “Radiation hardness studies of cooling fluids epoxies and capacitors for CMS pixel system”, M. Atac et al., NIM A 476 (2002) pages 676–679,

89. Radiation: Thin film resistors  Total resistance variation <2% after dose rate of 2.7e10 rad(Si)/s, total dose 1.8e5 rad(Si)/s and neutro flux 2.4e12n/cm2  Thin-film Thermo-resistor radiation hardness experimental results", Nikiforov et al., Radiation effects data workshop. 1997 IEEE, pages: 41-43

90. Radiation: Operational Amplifiers  Texas Instruments LM124-SP.  50 kRad (Si) TID  TID Dose Rate = 0.01 rad/sec (Si)  Linear Technology RH1499M  200 kRad :performance degradation but no failure

91. Accelerators and Ground Motion 91 There are many proposals of future next generation accelerator facilities in the world, those are electron-positron linear collider, very large hadron collider and muon collider. All of these colliders are very sensitive with respect to external ground motion noises. USPAS at University of Tennessee, Knoxville – 20 - 24 January 2014 Misaligned QP applies dipole kick to beam Beam oscillates along the accelerator and creates beam-beam offset at IP Particles with different energies oscillate differently fast This creates a beam size growth due to chromatic dilutions For CLIC courtesy of Jurgen Pfingstner-CERN, BE-ABP

92. Support Strategy 92 Laplace transform: Transmissibility: Compliance: Position and type of sensor important Feedback can be unstable S. Janssens, P. Fernandez, A&T Sector Seminar, Geneva, 24 November 2011

93. Positioning 93 Requested position-actual position = error Position control -Proportional Integral (PI) Controller -g increases step speed -Integrator removes offset -(additional Derivative control (PID) adds damping) R

94. Support Strategy 94 Instability in feedback Maximum gain limited by stability of system Unstable Stable

95. Error budgeting 95 S. Janssens, CLIC Meeting, Geneva 28 January 2011 Electronic noise sources P. Fernandez-Carmona Study of the electronics architecture for the mechanical stabilisation of the quadrupoles of the CLIC linear accelerator JINST_014P_1010 P. Fernandez Carmona

96. Error budgeting No significant difference in the noise transmission 96 S. Janssens, CLIC Meeting, Geneva 28 January 2011 Noise reduction

97. Concept drawing 97 Type 4 Alignment stage: H. Mainaud Durand R. Leuxe Lockable in longitudinal direction (transport) Stiff intermediate girder between alignment and stabilisation S. Janssens, CLIC Meeting, Geneva 28 January 2011 M. Esposito

98. 98 S. Janssens, CLIC Meeting, Geneva 28 January 2011 S. Redaelli, CERN ‘04 B. Bolzon, LAPP 2007 TMC STACIS™ Previous performances on stabilization of accelerator components TMC table: Stiffness: 7 N/ μm (value catalogue) 2 3

99. J. Frisch, SLAC 2001 C. Montag, DESY 1996 Previous performances on stabilization of accelerator components nm 99 S. Janssens, CLIC Meeting, Geneva 28 January 2011 3 2

100. Status/ Results: Water cooling tests T4 MBQ on equivalent supports 100 C. Collette, LCWS 2011, Granada, Spain ~ nominal water flow 1 l/min Very small measured increase (< 1 nm) Very conservative estimate increase of r.m.s. displacement of 2 nm (without stabilisation) S. Janssens

101. Machine precision vs size 101