Tevatron Beam Diagnostics: Boosting Collider Performance Vladimir Shiltsev, Ron Moore, Andreas...
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Tevatron Beam Diagnostics: Boosting Collider Performance
Vladimir Shiltsev,Vladimir Shiltsev, Ron Moore, Andreas JanssonRon Moore, Andreas Jansson
FNAL/Accelerator DivisionFNAL/Accelerator Division
05/01/2006 Tevatron Instrumentation 2
Winston Churchill
“Generals are always prepared to past wars.”
“Soldiers usually win the battles and generals get the credit for them.”
Napoleon Bonaparte
Tevatron Collider Run II Was/Is a Battle
05/01/2006 Tevatron Instrumentation 3
So, Purposes of This Talk Are:
• Give credit to soldiers• Show some remarkable luminosity-related
examples of diagnostics progress:– Lattice /helix issues BPM Upgrade– Reliability/uptime orbit stabilization + HLS +
vibrations– CDF/D0 discrepancy IP vertex diagnostics – Beam-Beam 1.7GHz Schottky + Tune
Stabilization – Losses on ramp IBEAM + FBI + Tune Tracker– Losses at 150 Head-Tail Monitor – DC beam AbortGapMonitor + LPM +SBD– Injection mismatch FWs + IPM + OTR
• Outline lessons learned during the Run II
05/01/2006 Tevatron Instrumentation 4
Tevatron Collider
1.96 TeV Proton-Antiproton Colider1.96 TeV Proton-Antiproton Colider- worlds’ most powerful accelerator- worlds’ most powerful accelerator
Run I (1992-96) t-quarkRun I (1992-96) t-quarkRun II (2001-09) Higgs, SS, >SMRun II (2001-09) Higgs, SS, >SM
05/01/2006 Tevatron Instrumentation 5
Overview of “the Battle”
05/01/2006 Tevatron Instrumentation 6
0.5-1% of loss Poor lifetime 0.5-1 mm orbit error Collimator malfunct Sequencer error
QUENCH !2-4 hrs to recover4-8 hrs for new pbars
or Blow Up
tune few 0.001 coupling ‘s wrong
instability kicker malfunct
1000’s of PSs
“Driver’s Nightmare”
Store #535Jun 15, 2001
05/01/2006 Tevatron Instrumentation 7
“Things going wrong”: 2001
Store #535Jun 15, 2001
So called “comfort plot” (at that time – more of discomfort) as seen by operators in Main Control Room and automatically saved in E-log
Shows intensity over the most critical times of injection, ramp and squeeze:
Blue – protonsRed – antiprotonsGreen – total (DCCT)
05/01/2006 Tevatron Instrumentation 8
Situation improved: 2005
Store #4116Apr 27, 2005
Note :Losses 1/20 of ‘018x proton intensity40x pbar intensity
05/01/2006 Tevatron Instrumentation 9
Importance of Helical Orbits
• Beams share beam pipe be separated – Helical separation ~(10-22)mm at 150 GeV– S ~(3-6) mm at 980 GeV
• Lifetime is strong function of S– 30 sec at 2σ , 50 hrs at 7σ– Aperture limited at 150 GeV “smooth”
05/01/2006 Tevatron Instrumentation 10
Orbit Smoothing and Understanding Optics
• ~0.5 mm rms orbit drift in 1-2 weeks• proton and pbar Qx,y, Q’, lifetimes vary significantly due to such COD needed regular orbit smoothing at 150, ramp, flat-top, squeeze, low-beta. … PLUS• lattice had to be known to <5% (was ~25%)• TBT not reliable• dependent on bunch structure/length• did not see pbars Decided to upgrade BPMs (2003-05)
“orbit – silver orbit”
+-2 mm at collisions
after about 2 weeks in September’02
05/01/2006 Tevatron Instrumentation 11
Beam Position Monitors
• Existing BPMs fitted with new electronics based on Digital Down-Conversion
• Resolution ~5µm (previously LSB was 0.15mm)
• Eliminated difference between coalesced and uncoalesced beams.
• Measures pbar orbit,too
S.W
olb
ers
et
al
A/DDDC FPGA
A/DDDC FPGA
Echotek board
Echotek board53MHz BPF
MVME2400
*Note that “resolution” includes real beam motion, mainly in the horizontal plane (synchrotron osc.)
05/01/2006 Tevatron Instrumentation 12
New BPMs De-coupling and Lattice measurement
• Calculating all optics functions and coupling correction using TBT data from many BPMs
E.G
ian
felice-
Wen
dt
# corrections
min
tu
ne
split
• Beta-functions measured to better than 5% accuracy on both helices, errors cor-rected, lattice modified so that β*=36cm29cm, giving ~10% gain in Luminosity
05/01/2006 Tevatron Instrumentation 13
-functions : before & after
Upgraded Tevatron BPMs !
Oct’05
Mar’05Vertical beta-function
A/V
alish
ev,
Y.A
lexah
inJ.
An
nala
, V
.Leb
ed
ev
150 m Horizontal beta-function
B0 D0
Change of beta @ IPβ*=36cm29cm gave ~10% gain in Luminosity
05/01/2006 Tevatron Instrumentation 14
Orbit stabilization
• Slow (~1/min) automatic continuous correction of orbit variations using several dipole correctors close to the IPs
• Standard at most Light Sources – only recently commissioned in Tevatron with new BPMs (old were too sensitive to bunch structure quench fear)
• Now need fast FB
orbit stabilization
ON
vertical
horizontal
0.4mm
1 day
V.R
an
jbar
05/01/2006 Tevatron Instrumentation 15
Sensitivity to quakes
“Fire-truck-quake” ~200 um orbit jitter
New diagnostics: tiltmeters, Water Levels on every LB quad
M8.7 Sumatra earthquake 03/28/05
05/01/2006 Tevatron Instrumentation 16
CDF detector sinking ~0.5 mm/year Interaction Point Moves inefficient b-tagging
Intentional move upon CDF
request
Reported by CDFSilicon Vertex Detector
05/01/2006 Tevatron Instrumentation 17
CDF and D0 IP Waist Diagnostics
J.Estr
ad
a/A
.Ch
an
dra
01/04
01/05 01/06
Vertical beta-function measured at D0
Jan’2004 to Mar’2006(“beam diagnostics for free”)
• Vertices of p-pbar collisions analyzed and processed
(on-line @ CDF , off-line with ~day delay @D0) IP
position, luminous region waist size vs z
05/01/2006 Tevatron Instrumentation 18
Tevatron: Life in the “Tune Box”
7th order resonances:
Q=4/7=0.571 -
HIGH LOSSES
12th order resonances:
Q=7/12=0.583 -
Bad lifetime
5th order resonances:
Q=3/5=0.600 –
EMITTANCE BLOWUP
proton
pbarevery bunch has every bunch has
its own tune!its own tune!
05/01/2006 Tevatron Instrumentation 19
Tune Diagnostics: 21.4 MHz Schottky
• Workhorse for shot setup. Operators determine tune from spectrum peaks
• Often needs excitation (VTICK)
• But:But: a) does not see pbars anywhere, b) very complicated by coherent tune lines,
• c) does not see bunch-by-bunch tunes
B.
Fellen
z
05/01/2006 Tevatron Instrumentation 20
1.7 GHz Schottky Detector
Slotted Waveguide Pickup
1.7 GHz 109 x 75 mm aperture
Bunch by Bunch Gate Generator
Analog Multiplexer
OscilloscopeVector Signal Analyzer
Phase Locked Multiplier Ethernet
BPF
53 MHz Tevatron RF
LPFBPFH or V Pickup
Protons
Antiprotons
Same as above
Injection Calibration Signal
Closed Circuit TV
1.7 GHz
38 NS
Tevatron Schottky Signal Processing
100 MHz @ 1.7 GHz 5 MHz @ 1.7 GHz 10 MHz
Tunnel Service Building
Revolution Marker
Gating Down Conversion R.P
asq
uin
elli
• Vertical and horizontal units• Proton and pbar ports• 100 MHz bandwidth
05/01/2006 Tevatron Instrumentation 21
1.7GHz Schottky Spectra
#322602/11/04
• Q and 1-Q lines are seen
• Fit gives:– Betatron frequency (accuracy ~0.001)– dP/P sum of two
widths– C_vh difference
of two widths– Emittance area
under the peaks
• For each bunch!
… non-invasive!
A.J
an
sson
/P.L
eb
run
05/01/2006 Tevatron Instrumentation 22
Tune stabilization
Starting tune correction
Pbar horizontal tune
Pbar vertical tune
• Operators use 1.7 GHz Schottky data to keep pbar tunes within a predefined range as the beam-beam tune shift changes
4 weeks
R.M
oore
05/01/2006 Tevatron Instrumentation 23
1.7GHz Schottky Bunch Tunes
Bunch-by-bunch tune variation ~0.005 – an indication of parasitic beam-beam interactions
05/01/2006 Tevatron Instrumentation 24
Plotting Bunch-by-Bunch Datafor each of 36 p + 36 pbar bunches
Live dataInstability @ 150 GeV resulted in
interesting intensity and emittance patterns
Logged dataProton bunch centroid motion during
longitudinal instabilitity
Observing differences in bunch-by-bunch behavior is very useful for understanding beam dynamics in the Tevatron
±4deg
05/01/2006 Tevatron Instrumentation 25
Longitudinal Instability Sampled Bunch Display and Phase Monitors
bunchlength
RF phase of bunch
bunch #
Bunch tomography
Weird bunch shapes during instability burst(snapshop taken by SBD)
No instability, continuously “dancing” bunches (RWM)
Fast (200Hz) longitudinal phase
monitor is under development
+-4
deg
05/01/2006 Tevatron Instrumentation 26
Sampled Bunch Display (SBD)
• Measure bunch intensities, lengths– Few – 350 × 109, 1-4 ns– Updates ≈ 1 Hz
• LeCroy WaveRunner 6200 captures waveforms over many turns in memory
– 2 GHz bandwidth, 10 G-samples/sec
• Macintosh G5 does signal processing– 200 tap (0.5 ns/tap) FIR filter removes
effect of dispersion in the long cable
• Resolution of intensity ~0.05% (5e9)
• Resolution of centroid position and RMS length ≈ 0.02 ns (RMS is ~2ns)
Figure 2: a proton bunch signal (raw) and after application of the FIR filter. The feature at the far right is a 3/4 % reflection. from one channel through the splitter to the other. Full height of the main bunch is ~5 amps.
05/01/2006 Tevatron Instrumentation 27
Longitudinal Oscillations Lead to Generation of DC beam in Abort Gaps
• The Tevatron operates with 36 bunches in 3 groups called trains
• Between each train there is an abort gap that is 139 RF buckets long– RF bucket is 18.8 ns Abort gap is 2.6 s
• Protons leak out of main bunches to the gaps. Tevatron is sensitive to few x 109 particles in the abort gaps (total beam ~ 1013) as they lead to quench on beam abort (kicker sprays them)
139 buckets
21 buckets 1113 RF buckets totalTrain
Bunch
Abort Gap
05/01/2006 Tevatron Instrumentation 28
Abort Gap Intensity Monitor
Photocathode
Dynode 1
Photocathode
HV below photocathode
Nominal PMT Behavior (Gated On)
Gated Off PMT Behavior
Dynode 2
Dynode 3
Dynode 4
Dynode 1
Dynode 2
Dynode 3
Dynode 4
HV below dynode 3
Hamamatsu gated MCP style PMT on loan from LBNL
• 5ns minimum gating time w/no noticeable settling time
• Very large extinction ratio
• Somewhat expensive (~$20K /tube)
• 2-stage Micro Channel Plate PMT – Gain of <= 106
• No sensitivity to pre-gate light
R.T
hu
rman
-Keu
p
05/01/2006 Tevatron Instrumentation 29
DC Beam in Abort Gap:TEL On/Off/On
AGM is calibrated wrt to DCCT - the most precise Tev instrument.
05/01/2006 Tevatron Instrumentation 30
Intensity Measurements: DCCT and FBI
• DCCT (DC Current Transformer)– Typical intensities 109 → 1013
– Noise ~0.5 e9 or ~0.005% max
– 24-bit ADC samples @ 6.9 MHz
– Output 128-sample average @ 54 kHz
– Calibrate via external pulser
– N_p+N_pbar together
• FBI (Fast Bunch Integrator)– Bunch-by-bunch intensities via RWM
– Narrow (1) & wide gates (5 buckets)• Main and satellite bunches
– Updates @ up to few hundred Hz
– Sensitivity to temperature improved
– Calibrate via DCCT• Few % correction for satellites
DCCT
Receiver
TBEAM Front-End * ~18 bits
T:IBEAMB - E13
T:BEAM - E12
T:IBEAM - E12
T:IBEAMS - E10
MADC (single sample, 12 bits)
DCCT
Amp.
DCCT
Receiver
TBEAM Front-End * ~18 bits
T:IBEAMB - E13
T:BEAM - E12
T:IBEAM - E12
T:IBEAMS - E10
MADC (single sample, 12 bits)
DCCTDCCT
Amp.
B.
Fellen
zT.M
eyers
Resistive Wall Monitor: Ceramic break with 80 120Ω resistors.
Signals sampled at four locations are summed.
05/01/2006 Tevatron Instrumentation 31
Beam Lifetime Depends on Chromaticity
• Two methods for fast Q’ measurements: – Head-Tail Monitor– Fast and Accurate TuneTracker
Loss rates (LOSTP) versus chromaticity
0400800
120016002000
0 2 4 6 8
Horizontal Chromaticity
Loss r
ate
s (
Hz)
(CDF Detector Proton Loss Counters)
05/01/2006 Tevatron Instrumentation 32
Fast Q’ Head-Tail Monitor
• Particles with different dP/P have different tunes head-tail phase difference ~Q’
• Just few pi d kick• Accuracy ~0.5
unit • Very fast method
– Ops like it!
• Currently used for monitoring– No difficulty to
measure Q’ with octupoles
V.R
an
jbar
0 200 400 6002
1
0
1
2Head minus Tail position
turn number
mm DXi
i
.
05/01/2006 Tevatron Instrumentation 33
Fast and Accurate Tune Tracker
• Beam is lightly excited over a frequency range around f_betatron
• Zero phase response frequency declared =Q
• Accuracy in Q ~0.0001• Very fast method
(3Hz)– Works on every Tev
ramp and in LB squeeze
• Change dP/P and determine Q’– Stat accuracy ~0.2– Syst error ~0.5 unit
Determine and track Phase=0 frequency
C.Y
.Tan
05/01/2006 Tevatron Instrumentation 34
0 10 20 30 40channel #
0
5
10
15
20
25
30
35
nrut#Quadrupole Oscillations due to
Lattice Mismatch: Ionization Profile Monitor
• Single bunch turn-by-turn beam size measurement.
• See separate talk.
1 cm
A.J
an
sson
05/01/2006 Tevatron Instrumentation 35
OTR Monitor
• 5 µm aluminized mylar foils• Rad hard camera, 130x170µm
size pixels• See poster session!
V.
Scarp
ine
05/01/2006 Tevatron Instrumentation 36
Both Instruments under development, but the first results are interesting:
IPM shows significant (~30%) quadrupole oscillationsOTR shows no size change over 1 turn (#2 vs #1, note ampl.)
OTR, vert
Turn #1Turn #2
… just one example of importance of having several instruments for cross-checks
0 5 10 15 20 25
1
1.1
1.2
1.3
IPM, vertmm
05/01/2006 Tevatron Instrumentation 37
Cross- Checks and -Calibration
• Intensity: DCCT and FBI and SBD– DCCT is most precise, but limited function– FBI and SBD within 1%, multi-functional
• Phase oscillations: SBD and LPM (slow and fast)
• Tunes: Schottky 21MHz, 1.7GHz, TuneTracker– All three in operations for different tasks– Absolute differences dQ~0.005, relative changes <0.001– TT fastest and precise, 1.7GHz most versatile
• Emittances: Flying Wires, SyncLite, Schottky – Tons of efforts to bring the three to within ~10%– FWs are ~main tool, used for 1.7 GHz Schottky calibr-n
• Luminosity: CDF and D0 different by ~20% (!)
05/01/2006 Tevatron Instrumentation 38
Lessons Learned - I
Due to peculiarities of SC synchrotron operation, non-invasive beam diagnostic instruments should be preferred, effects of intrinsically invasive ones minimized (FW 337um)
Having two or more instruments for same beam parameter measurements (makes life more complicated to bring them together but) makes the data more trustworthy
Fast data collection rate (at least 1 sec for all channels) is a must – at all stages, for all bunches, all the time – and saved for years (for postmortem)
Detectors have tons of beam diagnostics, so good communication channels with them are important
05/01/2006 Tevatron Instrumentation 39
Lessons Learned - II
Accept help/ideas from other groups/labs – many of them have invaluable expertise:- CD: BPM upgr; PPD: BLM upgr/SL/beta* monitors; LBL: Abort Gap Monitor MCP-PMT; ANL: e-cloud detectors, etc.
An instrument development is fast, compared to time needed to make it “fully operational” and satisfactory for operators and physicists – a lot of
efforts went into that
Team up diagnostics developers and users from the very beginning till commissioning of the instruments (and even beyond that – in operation)
05/01/2006 Tevatron Instrumentation 40
Teaming Up for Instrument Development
Instruments Developers Commissioners, Users Beam Line Tuner D.McGinnis/V.Scrapine J.Annala dEmm@ Inj, ”last sec” V.Scarpine A.Xiao/J.Annala BPM upgrade S.Wolbers/R.Webber M.Martens/J.Steimel 21.4MHz Shottky B.Fellentz P.Lebrun/D.Still 1.7GHz Shottky R.Pasquinelli A.Jansson/V.Shiltsev Tune Tracker C.Y.Tan C.Y.Tan/J.Annala SyncLite/Abort Gap Monitor R.Thurman-Keup A.Valishev/V.Shiltsev Flying Wires J.Zagel/S.Pordes A.Jansson/E.McCrory IBEAM+SBD+FBI R.Flora/S.Pordes A.Tollestrup/J.Annala Head-Tail Monitor V.Ranjbar V.Ranjbar Baseband Schottky A.Semenov/C.Y.Tan
V.Lebedev/J.P.Carneiro Vacuum Diagnostics/RGA B.Hanna V.Shiltsev HLS/Vibrations J.Volk/T.Johnson V.Shiltsev/J.Annala Longitudinal Phase Monitor A.Ibrahim J.P.Carneiro/V.Shiltsev Luminosity+IP diagnostics CDF/D0 V.Papadimitriou/V.Shiltsev IPMs/OTRs A.Jansson/V.Scarpine A.Jansson Beam Loss Monitor upgrade J.Lewis/S.Pordes J.Annala/D.Still Software (DLPlotter, OAC, SDA) T.Bolshakov/Cntrls
R.Moore/J.Slaughter
05/01/2006 Tevatron Instrumentation 41
So, Have We Won The Battle?
Yes, but only one one of many…Yes, but only one one of many…
… …the campaign is not overthe campaign is not over
05/01/2006 Tevatron Instrumentation 42
“Waiting for Mr.Higgs…”
4 more years > quadruple luminosity integral may be Mother Nature will smile on
us
05/01/2006 Tevatron Instrumentation 43
And at the end…
On behalf of the Run II team, we’d like to thank all who took part in beam diagnostics development
and
Thank you for your attention!
05/01/2006 Tevatron Instrumentation 44
backUp Slides
05/01/2006 Tevatron Instrumentation 45
Fast Q’ Head-Tail Monitor
• Particles with different dP/P have different tunes head-tail phase difference ~Q’
• Just few pi d kick• Accuracy ~0.5
unit • Very fast method
– Ops like it!
• Currently used for monitoring– No difficulty to
measure Q’ with octupoles
V.R
an
jbar
0 200 400 6002
1
0
1
2Head minus Tail position
turn numberm
m DXi
i
.
05/01/2006 Tevatron Instrumentation 46
Special BPMs: Beam Line Tuner
K * (A - B) /(A + B)
Beam
A
B
StriplinePickup Position
PhaseAmplitude
Tuneetc
Signal Processing
Analysis
•Measure turn-by-turn position at injection
•Extract betatron oscillations, do closure for next injection
– Reduce emittance dilution from mis-steering
– Calculate expected emittance dilution
•Also determine tune, coupling, energy & phase mismatches at injection
•Also for post-mortem of lost stores– Stop continuous data acquisition on
abort– Look for signs of instabilities in “last
second” buffer
• Tevatron Stripline parameters– 1 meter long (< 1/4 )– ~30 dB directionality– Pickup gap = 83 mm– 0.65 dB/mm Sensitivity– Located near F0 for
maximum proton and pbar separation (in time)
05/01/2006 Tevatron Instrumentation 47
Digital Receiver BLT
• Of course, it measures only DIPOLE oscillations
05/01/2006 Tevatron Instrumentation 48
Instruments under developments, but first results are interesting:
IPM shows significant (>30%) quadrupole oscillationswhile OTR claims no size change over 1 turn whatsoever
17.5 20 22.5 25 27.5 30 32.5 35turn #
1.1
1.2
1.3
1.4
1.5
1.6
smrezismm
OTR, vert
Turn #1
IPM, vert
Turn #2
… just one example of importance of having several instruments for cross-checks
05/01/2006 Tevatron Instrumentation 49
LIST OF INSTRUMENTS
BLT+dEmm+”last sec” RM BPM+related AJ Shottky I + II+ III+TuneTrk AJ SL+AGM+FWs VS IBEAM+SBD+FBI RM Head Tail Monitor VS Vacuum+RGA RM HLS VS RWM+LPM AJ Luminosity+IP diagnostics VS Software (C49, D44, SDA, ArrView, DLPlotter, OAC)
RM
05/01/2006 Tevatron Instrumentation 50
Longitudinal Phase Monitor
sin
cos
FPGAADC
Q-10bits
I-10bits
x
x
ADC Clock
Gate Timing
Gate Timing
Beam Pick-up
(Stripline)
(SIMPLIFIED)
T
T
RF
T
T
RF
RF
RF
dtttf
dtttf
dtttf
dtttf
)sin()(
)cos()(
)sin()(
)cos()(
arctanˆ
A.I
bra
him
Linearity:
Simulated phase:
Measured phase*:
*Discrepancies explained by difference in RF voltage and shape asymmetry during acceleration
05/01/2006 Tevatron Instrumentation 51
BPM Turn-by-Turn
1113 / 5 Artifacts* Betatron Lines
R.K
utc
hke e
t al
*Sampling frequency is 7/5 RF, so clock phase varies slightly with a period of 5 turns. Resolution: 0.3 mm/sqrt(Hz)
05/01/2006 Tevatron Instrumentation 52
1.7 GHz Schottky measurements
Schottky Horizontal Sync lite HorizontalSchottky VerticalSync lite Vertical
#4058Note: Arbitrary scaling
Damper problems→ longitudinal blow up
#3989
NO fudge factors!!!
#4000RMS fluctuation around
trend line: 5 10-4
0.00
2 Pbar bunch #29 Intensity: 19 109
Emittance: ~17 mm mrad
Momentum spread
Emittance
Single bunch tune
SBDSchottky Horizontal Schottky Vertical
*Note that the 1.7GHz Schottky can not resolve the two normal modes of oscillation by frequency, hence it is insensitive to tune changes due to coupling.
05/01/2006 Tevatron Instrumentation 53
Schottky development II
• In-house development
• Similar to 3D-BBQ
• Looks at both positive and negative peaks
• Feed-back to eliminate LF and increase dynamic range
Digital Beam Tune Monitor based on 16 bit 100MHz Digitizer
RF CLOCK,
RevMarker,TCLK,
FPGA100MHz
14 bit DAC
Cable from Tunnel
Ethernet, OAC
INPUTs: BPM Plates
TRACK/ HOLD
10Mbit ETHERNET
(A-B)- LPF(A-B)
TRACK/ HOLD
A+B
100MHz 16 bit ADC
64MSRAM
DSPSHARC
Input from Plate
~40ns Hold
A,B
A–B
100MHz 16 bit ADC
LPF(A-B)
+
- Gain100÷150
Reset
A.S
em
en
ov
05/01/2006 Tevatron Instrumentation 54
Schottky Development
• CERN has provided Direct Diode Detection Base Band Tune (3D-BBQ) module
• By gating with RF switches, were able to separate proton and pbar signals
• Issue with 60Hz lines• Expert/Study tool for
the moment.
C-Y
. Tan
05/01/2006 Tevatron Instrumentation 55
Resistive wall monitor
• Ceramic break with 80 120Ω resistors. Signals sampled at four locations are summed. Calibration signal can be injected.
• Two monitors: one for FBI/SBD, and one for general use
• During early 36x36 operation, ferrite inside vacuum heated up and started outgassing. Fixed with a new type of ferrite
• Recently intermittent problems with some resistors. All swapped out.
old ferritenew
ferrite
B.
Fellen
z
05/01/2006 Tevatron Instrumentation 56
Longitudinal Phase Monitor II
• New development base on the same board as baseband Schottky.
• Yet to be tested.
2 Channels Longitudinal Phase Meter Based on 16bit 100MHz Digitizer
8
4
4 i
i
i
i
SiSi
8i
i
Si
FPGACYCLONE
Cable from Tunnel
Ethernet, OAC
INPUTs: BPM Plates 5MHz
GaussFilter
10Mbit ETHERNET
5MHzGaussFilter
100MHz 16 bit ADC
64MSRAM
DSPSHARC
RF CLOCK,
RevMarker,
TCLK,
100MHz 16 bit ADC
RF Refere
nce
~20ns
Phase
~100ns
ADC Sampl
es 18.8ns
A.S
em
en
ov
05/01/2006 Tevatron Instrumentation 57
Special Equipment on Low-Beta Quads
Each low beta quadrupole is now equipped with :• Tiltmeters with ~1 urad resolution (above)• Water level sensors with ~0.2 micron resolution (right )
J.V
olk
T.J
oh
nso
n
Hydrostatic Level Sensors on Low-Beta quads and Alignment data report that CDF detector is
continuously sinking by ~0.5-1 mm/yr, distorting
vertical position of ~dozen low-beta quadrupoles