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Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
1
MONALISA updateCould the messenger of bad
vibration news be the cause of it?
beam pipe
Shintake interference patter
Seismic Sensors
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
2
Overview
• Goal of ATF2 installation: Test if MONALISA vacuum system introduces vibrations onto Shintake monitor
• Installation of MONALISA vacuum system at ATF2
• Minimal Force system• Motion Stability during pump down measured by
KEK survey team
• Vibration Measurements of LAPP group • Fringe stability test done by Shintake
group (Tokyo University)
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Good progress• We kept within our proposed schedule
– As set out in ATF2 meeting 17 Jun 09
• All items arrived at KEK 1st July 2009– Brought to ATF2 roof within 15 mins of arrival
• On ATF2 roof– System assembled and retested
• Brought to ATF2 Final focus tunnel – Reassembled at IP Thursday 9th July and
tested
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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On the roof of the ATF2
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Schematic Layout of Pneumatics • Vacuum in end boxes connected through inner bellows• High pressure only connected to outer bellows chamber
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Sensor readout during pumping
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Into the ATF2 tunnel
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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The DBS was hoisted into placeFull assembly completed well
within one day
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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DBS pumped out: with rods in
• Reached 28 Pa with a different pump– vacuum integrity was unaltered
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Tilt sensor• Tilt change on Shintake ~5+5 rad
– After MONALISA DBS installed at IP
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Forces measured pumping down when mounted at ATF2 IP
Regulator cycle ~225 s
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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(x,y,z) Physicists coordinates• In the following we’re using the physicists
coordinate frame
Y
X
Z
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Tracking QD0 motion in Z• Set MONALISA at operational pressure
– Pumped out vacuum vessel– Over-pressure in outer bellowed chamber
• Set up independent tracking of QD0– Used FARO to survey QD0 position changes– Keyence laser meter tracked QD0 mounted
on SD0 base plate
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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KEYENCE tracking QD0 Z
Readout sensor in mV
10 V = 5 mm
1 mV = 0.5 m
Readout with ourADC/LabVIEW DAQ
QD0
Supported from SD0
KEYENCE
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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FARO survey instrument
FARO
Retro
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Comparison of FARO & KEYENCE
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Tracking QD0 motion in Z
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Tracking QD0 motion in X
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Left-right QD0 mover tests
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Left-right QD0 mover tests
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Left-right QD0 mover tests
DBS spring constant is small enough to let QD0 move freely
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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What to learn from this measurements?
• We are told that static tolerances for QD0:– 100μm in x,y,z
• Our measurements show that even with the current pressure control system we meet this tolerance.
• The low spring constant of the DBS allows the QD0 mover to move the magnet unhindered.
• Dynamic tolerances: vertical: 10 nm, (between Shintake and QD0) horizontal: 500 nm
along beam: 10 μm
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Vibration Measurementsperformed by Benoît BOLZON (LAPP)
taken from talk presented at ATF2 meeting July 15.
1. Relative motion calculation using representative absolute motion
2. Impact of Monalisa on vibrations (3 directions) between: - Shintake and QD0 with and without pressure - QD0 and QF1 with pressure Comparison of measurements with/without Monalisa Measurements without MONALISA have been repeated two weeks ago with cooling water flowing inside FD
3. Conclusion
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Choice of a representative ground motion measured at ATF2 Choice of a high ground motion during shift period
Friday 12/12/08 at 3pm Above 0.2Hz: 218nm Above 1Hz: 128nm
Amplitude almost the same during 4 hours of shift
Choice of ground motion at 3pm representative
24
Relative motion calculation by taking this ground motion PSDgm
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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• Impact of Monalisa on vibrations between: - Shintake and QD0 with and without pressure - QD0 and QF1 with pressure Comparison of measurements with/without Monalisa
Vibration measurements between Shintake and QD0
Vibration measurements between QD0 and QF1
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
2626
Vibration transmission between Shintake and QD0
Vertical direction
Almost same coherence: - With/without Monalisa - With/without pressure
Only difference: QD0 resonance slightly lower due to Monalisa weight
- No Monalisa: 65.3Hz - With Monalisa: 60.3Hz
With Monalisa: Same transfer function with/without pressure
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
2727
Vibration transmission between Shintake and QD0
Vertical direction
Below 4Hz: increase of relative motion due to not enough high SNR(coherence very close to 1: relative motion should not increase)
Relative motion above 4Hz (should be the same than above 0.1Hz) :
Relative motion above 4Hz: - No Monalisa: 5.0nm - Monalisa with pressure: 5.7nm - Monalisa without pressure: 5.8nm
Almost no change compared to tolerances
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
2828
Vibration transmission between Shintake and QD0
Direction parallel to the beam
Almost same coherence: - With/without Monalisa - With/without pressure
Only difference: QD0 resonance slightly lower due to Monalisa weight
- No Monalisa: 18.0Hz - With Monalisa: 16.6Hz
With Monalisa: Same transfer function with/without pressure
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
2929
Vibration transmission between Shintake and QD0
Direction parallel to the beam
Same relative motion with/without Monalisa (even better with Monalisa above 7Hz) Same relative motion with/without pressure in Monalisa
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
3030
Vibration transmission between Shintake and QD0
Direction perpendicular to the beam
Almost same coherence: - With/without Monalisa - With/without pressure
QD0 resonance almost the same:
- No Monalisa: 20.4Hz - With Monalisa: 19.2Hz
With Monalisa: Same transfer function with/without pressure
SM resonance higher with Monalisa (59.6Hz 55.0Hz): good!
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
3131
Vibration transmission between Shintake and QD0
Direction perpendicular to the beam
Same relative motion with/without pressure in Monalisa
Same relative motion with/without Monalisa (even better with Monalisa above 10Hz)
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
3232
Vibration transmission between QD0 and QF1
Vertical direction
With Monalisa: QD0 and QF1 resonances slightly appear (factor 5) since QD0 resonant frequency is slightly lower (due to Monalisa weight)
Without Monalisa: QD0/QF1 resonances almost do not appear (very thin peak) since:
their frequencies are almost the same QD0/QF1 move in phase (very close to each other)
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
3333
Vibration transmission between QD0 and QF1
Relative motion increase of 2nm with Monalisa due to QD0/QF1 resonances (decrease of QD0 resonant frequency) : very low! Solution: put a mass on QF1 to decrease its resonant frequency down to QD0 resonant frequency
Vertical direction
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
3434
With GM/flowing cooling water, relative motion of SM to QD0: Tolerance Without
MonalisaWith Monalisa(with/no Press)
Vertical 7 nm 5.0nm 5.7nm/5.8nm
Perpendicular to beam ~ 500 nm 16.7nm 16.7nm
Parallel to the beam ~ 10,000 nm 17.2nm 17.2nm
Tolerances still achieved with Monalisa (almost no influence) N.B: No influence of the regulation system With GM/flowing cooling water, relative motion of QF1 to QD0:
Without Monalisa
With Monalisaand pressure
Vertical 5.0nm 7.0nmPerpendicular to the beam
8.9nm 34.2nm
Parallel to beam 10.9nm 26.2nm In vertical direction: almost no influence of Monalisa In horizontal directions: still acceptable because of the large tolerances A solution: put a mass on QF1 to get same resonances than QD0 ones
This is not an issue!!
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
35
Phase StabilityTaken from the talk presented by
T. Yamanaka at ATF2 meeting 15 July 09
• Motivation– Shintake monitor uses laser interference fringe
pattern to measure beam size.– It is important to know the stability of the fringe
position ( = fringe phase).– However, it is impossible to measure it at the IP
Measure fringe phase stability indirectly off the IPand get the information about the IP fringe
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Phase Stability Measurement
Microscope Lens
Linear Image Sensor
Measure fringe profile
Fourier transform and get the peak frequency
Calculate the phase at the peak frequency
Make interference fringe again on the lens and Magnify
IP
Schematic of Phase Monitor
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Measurement for MONALISA
• Phase stability is the key of the Shintake monitor• Checked the effect of the MONALISA system
1. without MONALISA
2. MONALISA is mounted on the Shintake monitor table and QD0, double bellows system is activated
3. MONALISA is mounted, the MONALISA chamber is opened to atmosphere
• All the measurements were performed in the midnight.
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Without MONALISA
1 min phase stability (RMS)Long term time variation of the phase
Histogram of 1 min phase stability
Mean: 135 mradRMS: 52 mrad
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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MONALISA Mounted, Double Bellows System Activated
1 min phase stability (RMS)Long term time variation of the phase
Histogram of 1 min phase stability
Mean: 163 mradRMS: 49 mrad
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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MONALISA Mounted,Atmospheric Pressure
1 min phase stability (RMS)Long term time variation of the phase
Histogram of 1 min phase stability
Mean: 153mradRMS: 39 mrad
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Summary
• 1 min phase stabilityCondition Mean [mrad] RMS [mrad]
without MONALISA 135 52
MONALISA, Activated 163 49
MONALISA, Atmospheric Presssure
153 39
• It seems to be a little bit worse when MONALISA is mounted.• It seems to be a little bit worse when the double bellows system is activated.• However, there exists not a little time variation of the phase stability so it can be say MONALISA system doesn’t influence the fringe phase stability so much.
Ref. ) 135 mrad and 163 mrad phase stability corresponds to 5.7 nm and 6.9 nm fringe position stability in 174 degree crossing angle mode.
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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So what do we learn from this
• The messenger of the news is not affecting its message:– We do not cause undue vibrations.
• The double bellow system produces very small forces
• Care is required when using a vacuum system
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Vacuum System
8 way fibre ribbon
Tapered hole
Vacuum vessel wall
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Summary & Outlook
• MONALISA vacuum system worked well– Many thanks for the wonderful support we got!
• The next step is to do optics tests with the vacuum system in place to gain calibration constants.
• Our goal is to get first position measurements to the Shintake group next spring/summer.
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Implications for MONALISA at CLIC
• Important to be prepared if vacuum system should be needed– Idea mount a flange on the bottom of the magnet– This flange will hold retros– This flange can be used to attach a future vacuum
system• We probably need a force neutralizing double
bellows system as well, since the magnet is on movers.– Nee big enough a hole through the support structure
to allow a double bellow system– Integration
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
47
Non-vacuum system
• The following systems are (almost) ready– Lasers that can be brought to CERN– Readout including Crate, amplifiers, ADCs
• We are currently designing the interferometer heads that we wish to bring to KEK. We can easily build a few additional heads for CERN, although the idea is of course to further develop and adapt the heads to the CLIC specific needs
• We need to tackle things like placement of laser/readout with respect to the magnet to address laser safety, purchase fibres....
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Forces on frame during pumping
• Cycled bellow chamber pressures– Inner chamber 100 kPa to 25 Pa to 100 kPa– Outer chamber 100 kPa to 140 kPa to 100kPa
• Measured forces– Using recalibrated force sensor
• Independently calculated forces– Based on SMC pressure sensors
• One for each chamber
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Tunnel preparation
Terunua-san installed pipe across the inside of the ATF2 final focus tunnel roof
Equipped with 2 hoists
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Mounting Shintake components• Plate mounted using M30 hooks
• End box mounted using hoist
Cables
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Mounting QD0 end box• Beeswax was placed on QD0 surface
– To ensure good vibration coupling to magnet
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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End boxes mutually aligned
• Laser light projected along accelerator axis
• Shintake end box – (left-right adjustable)– Moved to match QD0
end box
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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FARO compared with KEYENCE
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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FARO tracking X and Z
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Over-pressure regulation• Over-pressure regulator does not behave
as we would like
Control Signal /V
Overpressure / kPa
0
40
Vmax0
No response for over-pressure requests less than (50 mbar)
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
56
Required over-pressure regulation• Would want a straight line relationship
even for very low over-pressure
Control Signal /V
Overpressure / kPa
0
40
Vmax0
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
5757
Vibration transmission between Shintake and QD0
Vertical direction
No pressure
Transfer function measurements done during 4 hours the night (quiet) Frequency resolution: 0.016Hz Time resolution: 19 minutes
Pressure
Tim
e
Frequency
Am
plit
ude
Frequency
Am
plit
ude
Tim
e
Vibration measurements (with pressure in Monalisa) done simultaneously with frange measurements of SM
Same transfer function (with and without pressure) over time
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
5858
Vibration transmission between QD0 and QF1
Direction parallel to the beam
With Monalisa: QD0/QF1 resonances slightly appear (factors 5) since QD0 resonant frequency is slightly lower (due to Monalisa weight)
Without Monalisa: QD0/QF1 resonances almost do not appear (factors 2/3) since:
their frequencies are almost the same QD0/QF1 move in phase (very close to each other)
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
5959
Vibration transmission between QD0 and QF1
Direction parallel to the beam
Relative motion increase of 15nm with Monalisa due to QD0/QF1 resonant frequencies Very low increase compared to tolerances (500nm)
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
6060
Vibration transmission between QD0 and QF1
Direction perpendicular to the beam
With Monalisa: QD0/QF1 resonances slightly appear (factors 5 and 3) since QD0 resonant frequency is slightly lower (due to Monalisa weight)
Without Monalisa: QD0/QF1 resonances almost do not appear (factor 2) since:
their frequencies are almost the same QD0/QF1 move in phase (very close to each other)
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
6161
Vibration transmission between QD0 and QF1
Direction perpendicular to the beam
Relative motion increase of 25nm with Monalisa due to QD0/QF1 resonant frequencies Very low increase compared to tolerances (500nm)
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
62
Backup
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
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Remark
• 1 minute is an assumed one beam size measurement time with the Shintake monitor.
• 2π [rad] phase corresponds to one period of the interference fringe pitch
crossing angle [deg] fringe pictch [μm] 100 mrad phase stability [μm]
2 15 0.24
8 3.8 0.061
30 1.0 0.016
174 0.27 0.0042
Tue 22 Sept 2009Stabilization Day 7Oxford MONALISA
64
Measurement in Last Year
Measurement in summer of last year
Mean: 384 mradRMS: 50 mrad
Last year This year
Laser repetition frequency
10 Hz 6.25 Hz
Measurement frequency
10 Hz 1.5625 Hz
Laser output power Low Maximum
Laser and chiller location
side of the optical table
Laser room outside of the shield
Difference between last year and this year measurement