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

2. 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)

3. • 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

4. • 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

5. Terunuma-san

6. Terunuma-san

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

8. 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

9. 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

10. 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

11. 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

12. 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

13. 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

14. 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

15. 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!