STABILISATION WG MEETING th FEBRUARY 2013 CTC SUMMARY The research leading to these results has received funding from the European Commission under the FP7 Research Infrastructures project EuCARD

2 Objectives meeting  Meet up  Manpower & collaboration status  Review status  Final focus status  MBQ stabilisation and Nano-positioning status  Other  Milestones 2013  Make a list of open points + determine priorities  Share work load  Decide on follow up meetings  AOB

3 CERNS.Janssens (Fellow) 100% K.Artoos (50%) Designers: R. Leuxe, C. Eymin (jobs) A. Gaddi, H. Gerwig, F. Ramos LS1 MBQ stabilisation + nano-pos. Sensor development Pre isolator studies LAPP/ Symme A.Jeremie, G.Deleglise 20% Additional physicist requested L. Brunetti (70%), J.Allibe (=> July 2013) G. Balik (=> Sept. 2014), J.P. Baud 40% S. Vilalte (20%) SYMME: B. Caron Final focus stabilisation Sensor development ASL (ULB)Chr. Collette, D. Tshilumba, J. Amar (PhD, Master students) “Brains back to Brussels” Grant until end 2013 (could be extended) Controller designs MBQ & Final Focus Sensor R&D Networking CEA/IRFUF. Ardellier Desages M. Fontaine, N. Pedrol-Margaley (no %, K contract finished) Optical measurement methods Calibration standard Meeting at CEA to be planned Manpower + collaboration status

Final focus stabilisation 4 40 to 100 ton pre-isolator Frequency 1-2 Hz CAM based alignment system Cantilever 50 Hz Active stabilization system IP Beam based feedback So far no link was made between all systems (control)

5 Ongoing work FF IP Beam based feedback Mechanical stabilisation

6 Ongoing work FF Precise model Noise of sensors limits stability reached 1.Tests with other sensor Guralp 3ESP + Better noise curve than Guralp 6T -More difficult transfer function Implementation ongoing - Size of sensor 2.Development sensor (patent) Prototype 1 ready and being tested Miniaturized prototype 2 end of March April: testing on active support

7 Ongoing work FF Study of active cables to damp cantilever (CLIC/ILC) + possibility positioning + improves transfert function + Improves stiffness against direct forces - Implementation of cables in push pull detector Christophe showed possible control strategies and showed 3 limitations due to: 1.Sensor tilt to horizontal coupling 2.Flexible connections between sensor and actuator 3.Flexible support Advice to have an intermediate soft support (20Hz)

8 Ongoing work FF What is needed to damp/influence peak of pre-isolator mode? S. Janssens Comparison several strategies Velocity feedback xp Combination x and xp feedback Issues pre-isolator: 1.Ground motion at 1 Hz > 12 m is not coherent (LHC GM measurements), active damping and transmissibility reduction at 1 Hz is needed 2.Compliance too high, demonstrated with small airflow 3.Maximum 1 µrad roll allowed for luminosity 4.Cantilever is huge lever arm, requiring even higher resolution on pre isolator actuators

9 Ongoing work FF S. Janssens PID on xp + activ stab. Possible transfer function between ground and QD0 + no drift at low freq Possibility to change Preisolator position !!!No noises or filters in it!!!!

Final focus stabilisation 10 Open points: 1.QD0 inside detector ? No decision next two years 2.Mechanical Design pre isolator is linked to having the magnet inside the detector or not 3.Noise model near particle detector should be studied/measured. Coherence ? 4. For FF go from integrated RMS to integrated luminosity, model and test different solutions 5.Make the link between the two FF and between FF and BDS and MBQ for multiple d.o.f. 6.Choice and performance fp actuators: noise curve, force autority? Mock-up construction pre isolator: decision : Not at the moment Increase quality and number of integrated models Study existing hardware components: contact industry for existing components We need to set a clearer target for FF

Further Research proposal (tender/inhouse) Research goals 1. Make a dynamic model of the system presented. For this model: give the transfer functions between all degrees of freedom and the ground make a table of all the modal frequencies and their decomposition in eigenvectors graphical representation of the evolution of the modal frequencies and their decomposition for a changing γ from 0 up to 15 degrees which changes the position of m g, m QF1, m st, m stb, m QD0. What is the effect of increasing the 1 st mode to 20 Hz? 2. Propose the best active damping (velocity feedback, Integrated Force Feedback,…) system which: damps the 1 st mode of M pi critically Reduces the 1 st mode from 20 Hz to 1 Hz through active control uses existing technologies compliant with the environmental parameters, does decrease the drop off above 2ωpi in the transfer function between w pi and x pi, for the ground vibrations specified, due to noise or any other limitations (actuator or sensors). Specify the number actuators/sensors (The 4 specified are a suggestion). Is it better to use a global controller or have each leg have its own SISO controller and decouple them with joints? Simulate the performance of the proposed isolation system in an environment with ground vibrations and applying actual sensor/actuator, sensitivity, noise and resolution. ~2 months ~5 months Requires a student

12 MBQ: build 3 modules “best available design” Functional performance testing + development time: Study and try assembly Requires controlled stable environment (Temperature, Vibrations, Access) Demonstration feasibility + ultimate performance stab. + positioning Water cooling + powering magnet Test module location not adapted for this. Magnetic measurements and fiducialisation Type 1 Test module with dummy magnet Integration in test module, connections to other modules, robust show case, transport, … Demonstration alignment and stabilization but not representative for CLIC tunnel Type 1 ISR Type 4 ISR Type 1 CLEX Type 4 Test module MBQ modules upgradable (bolted together, no welds). K.Artoos, Stabilisation WG, 21th February 2013

Main beam quadrupole stabilisation 13 Design and end of drafting MBQ type 1 stabilisation for ISR tests + CLEX, Testmodule: Week 11 Fabrication type 1: 1.5 month Start assembly type 1: end of April, Assembly 1 week Controller electronics type 1 ISR ready : end of April Testing type 1 ISR stabilisation : May + June (2 months) Assembly type 1 for test module: second week of May. Design and end drafting MBQ type 4 stabilsiation for ISR tests/test module: End of March Fabrication 1.5 month Start assembly type 4: Middle of May, assembly 1 week. Controller electronics type 4 ready: end of May Testing type 4 ISR stabilisation: June, July

Combine with alignment 14 Presentation Juha

Sensor developments 15 LAPP sensor (for FF and MBQ) NDA with CERN ULB sensor CERN “reversed engineering” sensors Out sourcing vertical MBQ sensor in industry (goal finish specification end march) Requested sensor model confirmed by B. Caron for FF + very useful feedback on specification

GM measurements 16 Vibration measurements test module Vibration measurements pulsed dipole CMS RB to RB measurements Proposal SLAC (M. Oriunno) detector technical noise measurements

Main open points 17 QDO inside detector? Radiation hardness: Can not go without shielding No manpower to design and test radiation hard components. More logical at later stage? Compatibility fast and large temperature changes Stray magnetic fields: Amplitude vs frequency?

Conclusion meeting 18 Very good contact and exchange with clear openings for collaboration No clear overall picture for Final Focus yet but several new data Needs info about L* Continue modeling and testing (LAPP, ULB) Join manpower for modeling (including luminosity) 2 nd round end of summer Needs more information on technical noise and GM model around detector Planning for three stabilised and aligned MBQ in 2013 Inertial sensors in pipeline GM measurements ATF2, possible CMS measurements Start point for list actions and open points Stab WG meeting two times/year + “hands on “ meetings Next WG meeting September