Alignment and stability session A.Jeremie (Sugahara-san KEK convener)

Outline Alignment and Stability 13:30 Alignment results of ATF2 beam line Ryuhei Sugahara (KEK) 13:50 Short report on FD magnet alignment Nobuhiro Terunuma (KEK) 14:00 Installation of HLS at the ATF2 Mika Masuzawa (KEK) 14:20 GM generator for ATF2 Benoit Bolzon (LAPP) 14:45 Short report on Monalisa measurements David Urner (University of Oxford)

• Alignment was performed with a Laser Tracker, a Leveling telescope and an Electrick Level • Magnetic field of QEA-mag were all measured at KEK, and their offsets, dX and dY, and Roll Angle were measured and recorded. Those errors were corrected in the alignment Sugahara-san

• Alignment for ATF2 magnets have been carried out, and have resulted alignment errors of 0.081mm for X, 0.121mm for Y and 0.080mm for Height in RMS • Current ATF2 beam line has an angle of 48 rad to the Y-axis • Only the last magnet, QD02A, needs to be improved in Y position Sugahara-san dX_summary

Terunuma-san

Terunuma-san

Alignment of SLAC QDs and SXs will be tried soon. Terunuma-san

Hydrostatic Leveling System Introduction The proposed Hydrostatic Leveling System (HLS) determines height differences between points. The disadvantage of using the equipotential surface as a reference is that the earth surface itself is not stable but in constant motion. Earth tides due to sun and moon Up to 30mm for a 130 m long undulator Can be modeled Ocean tide loading and atmospheric loading Can reach up to 30 mm Can’t be easily modeled Advantages: No direct line of sight needs to exist Not affected by optical refraction High accuracy Fully automated In-situ calibrating Equipotential surface is the reference Absolute measurements before beam based alignment SLAC team (G. Gassner & R.Ruland) kindly agreed to collaborate with us on HLS. 8th ATF2 Project Meeting June 9,2009 Masuzawa -san

8th ATF2 Project Meeting June 9,2009 Possible Installation locations: Plan A & B A: On top of the magnets Potential to connect the ATF and ATF2 Beam lines smoothly. B: On the concrete support 8th ATF2 Project Meeting June 9,2009 Masuzawa -san

8th ATF2 Project Meeting June 9,2009 Proposal (has not been approved yet) 31 m Access to/from the beam line Final Focus Q ATF2 ATF Plan D Plan C Plan C&D short span 8th ATF2 Project Meeting June 9,2009 Masuzawa -san

B.Bolzon GM generator A generator has been made in the past to simulate spatial and temporal properties of ground motion [A. Seryi, O. Napoli, “Influence of ground motion on the time evolution of beam in linear colliders”, DAPNIA/SEA, 95-04, August 1995]. Input parameters of this generator can be updated to fit measurements done on various sites in the world. Thanks to new measurements done in the ATF2 beam line with CMG-40T geophones and ENDEVCO 86 accelerometers, these parameters have been updated for ATF2 simulations. Relative beam motion due to all QFF motions Relative beam motion due to each QFF motion Beam relative motion to IP due to jitter of all FF quads almost within tolerances for 5% error on beam size measurements and high ATF2 GM Necessity to look at beam relative motion due to jitter of all quads

Integrated RMS of absolute/relative motion vs distance B.Bolzon Integrated RMS of absolute/relative motion vs distance Increase of relative motion with increase of distance up to 190nm at 45m (absolute motion of about 240nm) Very good agreement simulations /measurements for each distance Confirmed the quality of the parameter tuning Below 4m, measured and theoretical RM overestimated due to very high SNR needed and lower correlations than in reality (measurements) 12

Shintake Monitor mounting plate Calibration Study “Calibration” = Where are these components located on their mounting plate? Shintake Monitor mounting plate mounting plate QD0 What is the effect of calibration errors? a scale error in displacement measurements Simulated a “minimal” calibration scenario: e.g vibrations with amplitude 1μm would be limited in reconstructed accuracy to 3nm from calibration a long-term shift of 100 μm would be limited in reconstructed accuracy to 300nm 1mm uncertainty in component locations 0.3% scale error for vertical motion D.Urner

Plan Test vacuum and pressure feedback in Oxford next week Ship entire system to KEK to arrive by July1. Attach MONALISA system to the table: July 7th to 9th. Vibration measurements: July 9th to 15th. Detach MONALISA system from the table: July 15th to 17th. Store MONALISA system at KEK until final installation later this year or beginning of next year. Double bellow system D.Urner

Conclusion Great care has been taken for the alignment of magnets; still one or two magnets to finalize alignment FD alignment and 3 FF sextupoles to be aligned with new instrument HLS system: do we install or not? When do we need to decide? GM generator updated for simulation; FF magnets do not need stabilisation; at short distance, the simulation underestimates correlation Monalisa plans to test set up in ATF2 beginning of July: schedule tight!