C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch,...
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Transcript of C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch,...
![Page 1: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/1.jpg)
C/S-band cavity BPMs
A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi, E-S Kim, Y. I. Kim, A. Lyapin, D. McCormick, S.
Molloy, J. Nelson, Y.J. Park, S.J. Park,T. Smith,T. Tauchi, N. Terunuma, G. White.
SLAC, KNU, PAL, KEK, JAI-RHUL, KEK, ATFhttps://www.pp.rhul.ac.uk/twiki/bin/view/JAI/BeamPosition
![Page 2: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/2.jpg)
Summary of progress•C-band
•Normal resolution with 20 dB 200 nm
•Best resolution recorded, 20 nm
•S-band
•About 1 um (with 15 dB loss in cable)
•Unstable when DR-RF ramp is on
•IP
•Commissioning phase
•Y resolution ~100 nm (needs good IP steering)
•Write paper on Hardware and initial results (YI Kim, Lyapin, Boogert)
![Page 3: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/3.jpg)
Introduction• Earthquake damage : relatively light
• Main change to network : made old VME controllers inoperative, unable to boot
• Hardware
• Exchanged : MVME167 to MVME3100
• Integration of SLAC 16-bit digitisers
• Software upgrades : Over 40 large upgrades
• Automatic EDM
• Each polarisation has own reference, displays, processing, DAQ, etc
• Measurements and checks
• 714, C-band, S-band LO and CAL
• Digitiser noise spectra
• Analysis
• Calibration scale errors
• Multi-bunch
![Page 4: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/4.jpg)
Hardware changes in detail•Exchanged : MVME167 to MVME3100
•Integration of SLAC 16-bit digitisers
•C-band CAL tone broken
•S-band sources, rationalised and checked
•S-band cables, reorganised due to new IP region shield penetration
•Checked out Zygo straightness monitor system
![Page 5: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/5.jpg)
SLAC digitisers•16 bit
•4 channels
•120 MHz internal clock
•Excellent linearity
•Problem in impedance
•Appears to be 1 MOhm
![Page 6: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/6.jpg)
SLAC+SIS digitizers•Fully integrated
•6 SLAC ADC cards
•4 channel
•16 Bit
•Bipolar
•High linearity
•Low phase noise (internal clock)
•Impedance issue....
QuickTime™ and aH.264 decompressor
are needed to see this picture.
![Page 7: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/7.jpg)
SLAC impedance check
•IPY1 : Inserted
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SLAC digitiser impedance•Diagnostic check list
•Checked with multimeter (DC measurement)
•Triggered 25 MHz source
•Scope test at 50 Ohms
•Signal looks like it has no reflections
•Can be avoided in software even for references which have large Q compared with IPBPMs
Check TOMORROW
![Page 9: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/9.jpg)
C-band RF distribution•714 Input into RF
locking box, generates
•100 MHz digitiser clock
•LO
•LO has some sidebands
•Should check at down mixer electronics in tunnel
•Large amplification 5W
![Page 10: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/10.jpg)
C-band cal tone•Only visible damage
due to quake
•Temperature interlock for C-band CAL tone 5W amplifier
•Fixed!
•Need to check CAL tone to
•MPIP (done!)
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S-band system digitiser•New MVME-3100
•2 8-Channel SIS modules, enough for S-band system
•Clock and trigger still maybe an issue
•DR-RF on!!!!!!
•Propose to internally clock as have spare channels for multiple references now (IP BPMs moved to SLAC digitisers)
Install TODAY
![Page 12: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/12.jpg)
S-band signal cables•Cut down cables
•Length reduced by approximately 20 m
•Attenuation similarly reduced
•Need for hybrids/amplifiers probably gone
•Will install hybrids
BPMOld attn
(dB)New attn
(db)SF1FFx 14.9SF1FFy 14.4QF1FFx 14.5QF1FFy 14.9SD0FFx 14.6SD0FFy
14.7
QD0FFx 14.7QD0FFy 14.8REFS1 14.8
Measure TODAY
![Page 13: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/13.jpg)
S-band sources•8 and 20 GHz
Hittite sources
•LO and CAL tones
•Source power and frequency stability not such an issue but spectrum is important
•Need to propagate effect to down-converted signals
LO2kHz span
CAL8GHz 2 MHz span
![Page 14: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/14.jpg)
S-band RF distribution•At mixdown
electronics
•LO looks reasonable
•Completely unlocked from 714 MHz of ATF, why is there such a coherent change in BPM performance (IQ rotation) when DR-RF ramp is switched on
![Page 15: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/15.jpg)
Zygo straightness system•Email from Mike
Hildreth
•Check
•Laser (ok)
•VME system (ok-ish)
•Computers (ok)
•Laser path needs realignment
•Preparing for August planned trip by Mike H.
![Page 16: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/16.jpg)
Software changes in detail•Main change use to IP region BPMs
•Previously code used one reference cavity per dipole PAIR
•Totally automatic system configuration
•Generates all files (displays included from one master control file)
•More stable database, rarely have to change main DB configuration even if hardware changes drastically
•Complete system configuration in database
•Determine how the BPM system is operating, what is connected, how it is being processed
![Page 17: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/17.jpg)
Automation•Completely automatic configuration. Edit signal file and all
settings down to hardware, analysis and display changed
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Digitiser noise• Two types of digitiser
• Need to understand the effect of digitiser noise on BPM processing
• Two types of investigation
• Calibration tone (fit to sine wave)
• Data taken but need to process
• Beam off
• Done, results on right
BPMDigitise
rNoise [ADU]
QD10Xx rawSIS (14
bit) 2.53
QD10Xx proSIS (14
bit)0.12
IPAx raw SLAC (16 bit)
7.44 (/4=1.86)
IPAx pro SLAC (16 bit)
0.72 (/4=0.18)
![Page 19: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/19.jpg)
Frequency shifts•In normal
operation often notice temperature shifts
•Appear as linear phase in down-mixed signal
•Temperature changes cavity size, hence frequency
•Need to temperature monitor entire BPM system? Possible? Resolution?
Basic : -112 kHz/KBeam pipe-50-60 kHz/K
![Page 20: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/20.jpg)
t0 resolution•Beam arrival time (t0)
•Substantial jitter and then longer term drifts
•Phase correction algorithms depend on this number
•Measured in REFC1 diode detector
•Linear fit to rising edge of signal
•Better method?
Charge [10^10] t0 RMS [ps]0.3 6020.5 1600.8 331.0 32
0.3 x 10^10 e-
![Page 21: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/21.jpg)
Calibration Errors due to Slow Orbit Drift and Random Beam Jitter
•Record ~1000 pulses of position measurements
•Smooth using moving average with flat window of length equal to calibration step length in pulses
•Fit points separated by window length against positions in calibration scan to determine fractional error on position scale
•Subtract smoothed signal to leave random jitter
•Calculate random errors analytically
•Subtract jitter for BPMs on movers then repeat analysis
Frankie Cullinan
![Page 22: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/22.jpg)
Results
S/m
Frankie Cullinan
![Page 23: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/23.jpg)
23
IQ : Without bunch subtractionIQ : Without bunch subtraction
BunchNo
φ (rad)
|Δφ | (rad)
1 0.98778
2 0.32898 0.65883
3 -0.59777 0.92671
Rotation Angle:
o BPM is moved along Y axis at 200, 100, 0, 0μm positions respectively.
o I & Q are calculated in a similar way as single bunch calibration, without any bunch subtraction.
o With change in mover position, I&Q from 1st bunch moves along a straight line in IQ plane passing through (0,0)
o Steps along straight lines in IQ plane from 2nd and 3rd bunches shows the behaviour expected from a cavity BPM.
o IQ signal from a bunch is polluted by the decayed signal from previous bunches.
Nirav Joshi
![Page 24: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/24.jpg)
24
IQ : After bunch subtractionIQ : After bunch subtraction
BunchNo
φ (rad)
|Δφ | (rad)
1 0.98778
2 -0.04182 1.029609
3 -0.96794 0.926120
Rotation Angle:
Bunch Subtraction:
oi & q signals from BPM and reference cavities are subtracted separately before normalization.
oDecayed i & q from previous bunch is subtracted from current bunch.
oSubtracted signal is then normalized.
oPhase difference between bunches becomes even.
Nirav Joshi
![Page 25: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/25.jpg)
Future work•Cavity temperature monitoring
•Monitor temperature by frequency drift
•Ok for a phase detector but not dipole system
•Consider installing temperature monitoring on all BPMs
•Resolution of current system?
•High charge operation (question from Terunuma-san)
•Dipole saturation is always a problem
•Reference saturation is not an option (should not happen)
•Ordering 5 remote controlled C-band attenuators
•Understand entire BPM system error budget, statisical and systematic errors etc.
![Page 26: C/S-band cavity BPMs A. Aryshev (KEK), S. T. Boogert (JAI@RHUL), G. Boorman, F. Cullinan, J. Frisch, A. Heo, Y. Honda, J.Y. Huang, S.J. Hwang, N. Joshi,](https://reader034.fdocuments.us/reader034/viewer/2022051620/56649eff5503460f94c14d38/html5/thumbnails/26.jpg)
Summary•System is working well,
compared to pre-earthquake situation
•Many cases improved
•Significant software changes
•Expect some bugs, tried to remove most of them
•Improved maintainability
•Continue with pre-quake program
•Attempt to get high resolution operation for >1 week without calibration