cocoa me+1 blessing
DESCRIPTION
Cocoa ME+1 Blessing. James N. Bellinger University of Wisconsin-Madison 20-March-2009. Data used. 0T Distancemeter16-Nov average DCOPS11-Nov event Linkfrom Celso 3.8T Distancemeter1-4 Nov average DCOPS27-Oct event Linkfrom Celso PG - PowerPoint PPT PresentationTRANSCRIPT
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James N. Bellinger
University of Wisconsin-Madison
20-March-2009
Cocoa ME+1 BlessingCocoa ME+1 BlessingCocoa ME+1 BlessingCocoa ME+1 Blessing
James N. Bellinger 20-March-2009
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Data usedData used
0TDistancemeter 16-Nov average
DCOPS 11-Nov event
Link from Celso
3.8TDistancemeter 1-4 Nov average
DCOPS 27-Oct event
Link from Celso
PGPG within disk UR-0058 (2006) (Oleg cleaned it up)
Supplementary UR-0103 (2008)
PG of disk UR-0124 (after Craft)
James N. Bellinger 20-March-2009
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• Ideal– Ideal Geometry for Endcap+Link, default data
• 0T– Data from 0T, Link fit geometry/data from 0T
– Transfer plates from PG, rest of Endcap ideal
• 3.8T– Data from 3.8T, Link fit geometry/data from 3.8T
– Transfer plates from PG, rest of Endcap ideal
• Special– Data from 0T, Link fit geometry/data from 0T
– Transfer plates from PG, initial chamber pos PG
Cocoa Fit TypesCocoa Fit Types
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Cocoa Ideal Fit vs DDDCocoa Ideal Fit vs DDD
• Only 6 entries. Cocoa Ideal minus DDD geometry
• Ring 3 only
• Cocoa Ideal geometry fit is fine: “chi-squared” is 1.4 with 872 “degrees of freedom”
Cocoa pos – DDD pos
Mean,
microns
RMS,
microns
X -17 69
Y -55 52
Z -7 1
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Fit 0T- Fit Ideal
3.8T-Ideal
X Y Z X Y Z
ME+1/3/03 0.58 -2.17 -1.16 0.58 -2.14 -2.93
ME+1/3/09 2.31 -0.62 -4.38 2.2 -0.59 -4.39
ME+1/3/14 -0.32 -0.32 -3 -0.17 -0.17 -2.85
ME+1/3/20 0.11 -0.43 1.28 0.04 -0.13 -0.18
ME+1/3/27 1.03 -0.28 2.57 1.29 -0.35 -0.53
ME+1/3/33 -0.89 -0.88 8.33 0 0 -0.01
ME+1/2/02 0.9 -3.38 1.16 0.98 -3.66 -7.08
ME+1/2/08 3.46 -0.93 -0.54 3.51 -0.93 -7.89
ME+1/2/14 -0.07 -0.07 -0.93 0.07 0.07 -7.74
ME+1/2/20 -0.03 0.11 2.47 -0.1 0.37 -5.76
ME+1/2/26 0.92 -0.24 5.77 1.03 -0.28 -2.9
ME+1/2/32 -0.29 -0.27 5.3 -0.4 -0.4 -3.66
Chamber Z deviations Chamber Z deviations Cocoa 3.8T and 0T vs IdealCocoa 3.8T and 0T vs Ideal
Cocoa 3.8TCocoa 0TCocoa Ideal
Ideal fit uses ideal geom and nominal measurements
HSLM6 bad due to blocked IR target
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Cocoa Fit 3.8T - Fit 0T
mm
Cocoa Fit 0T - P.G.
mm
ME+1/3/03 -1.76 -0.71
ME+1/3/09 -0.01 2.08
ME+1/3/14 0.15 2.27
ME+1/3/20 -1.46 -0.24
ME+1/3/27 -3.1 -1.88
ME+1/3/33 -8.33 3.27
ME+1/2/02 -8.24 0.16
ME+1/2/08 -7.36 2.46
ME+1/2/14 -6.81 0.25
ME+1/2/20 -8.23 -0.62
ME+1/2/26 -8.67 0.65
ME+1/2/32 -8.96 2.11
The Cocoa 0T fits are not far from the PG numbers
The 1_2 chamber deviations with field agree w/ Celso's numbers
The HSLM6 fits are bad because of a blocked IR target
Chamber center Z deviationsChamber center Z deviations
Rms=1.5
Rms=1.0James N. Bellinger 20-March-2009
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Fit Ring Fit Ring (average of all chambers)(average of all chambers) Position Position Deviations from IdealDeviations from Ideal
0T-Ideal
X
0T-Ideal
Y
0T-Ideal
Z
3.8T-Ideal
X
3.8T-Ideal
Y
3.8T-Ideal
Z
+1/3 .74 -.76 -.94 .79 -.68 -2.18
+1/2 .98 -.98 1.59 1.10 -.97 -6.27
PG
(disk).58 -1.37 0.57 NA NA NA
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ME+1/3/03 -0.5 1.53 2.03
ME+1/3/09 -0.83 1.99 2.83
ME+1/3/14 -1.14 1.09 2.23
ME+1/3/20 0.41 2.63 2.22
ME+1/3/27 -1.93 -0.69 1.25
ME+1/3/33 2.22 0 -2.22
AVERAGE -0.8 1.3 2.1
At disk bottom
At disk top
Tilts (mrad) determined from DCOPS Z positions at upper and lower ends of each chamber
0T 3.8T 3.8T-0T
ME+1/3 chamber tilts (mrad)ME+1/3 chamber tilts (mrad)
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Uses the DCOPS PG targets to predict the DCOPS dowel positions for the Xfer DCOPS and the ME+1/3 DCOPSDifferent target holders at ME+1/3/09_outer and ME+1/3/27_outer?? Inconsistent
XFERPG Pred
1/3OutPG Pred
1/3InPG Pred
XFerCocoa
1/3OutCocoa
1/3InCocoa
XFer Coco-PG
1/3OutCoco-PG
1/3InCoco-PG
HSLM16823.54
6822.89
6823.74
6822.07
6821.67
6822.52
-1.47 -1.22 -1.22
HSLM26814.79
6809.68
6817.57
6819.28
6818.13
6819.57
4.49 8.45 2.00
HSLM36817.67
6816.99
6820.12
6819.78
6818.86
6820.82
2.11 1.87 0.70
HSLM46826.79
6825.80
6826.16
6825.68
6825.09
6824.39
-1.11 -0.72 -1.77
HSLM56826.27
6817.91
6828.22
6825.62
6824.18
6827.51
-0.66 6.27 -0.71
HSLM66829.10
6826.17
6828.15
6838.06
6833.60
6829.79
8.97 7.43 1.64
PG targets and Cocoa 0T Fits:PG targets and Cocoa 0T Fits:Z of DCOPS dowelsZ of DCOPS dowels
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DCOPS from PG vs Cocoa 0T FitDCOPS from PG vs Cocoa 0T FitSummarySummary
DCOPS Dowel positions: 0T Cocoa fit – predicted from PG of DCOPS targets
Reference: mean= 0.67, rms=2.29mmME+1/3_outer: mean= 2.93, rms=3.83mmME+1/3_inner: mean= -0.20, rms=1.37mm
HSLM6 is not included
RMS is large, and at least partly attributable to PG problems
“Reference” = reference DCOPS on transfer plateJames N. Bellinger 20-March-2009
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Deviations from IdealDeviations from Ideal
Chamber mounting errors: should not exceed a few mm
PG measurement errors: supposedly 300 microns but I don’t believe that anymore
Cocoa fitting errors
Real distortions because of the field
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Cocoa Estimated ErrorsCocoa Estimated Errors
Cocoa returns some estimated errors for quantities in the coordinate system of the mother volume(Cocoa uses a hierarchical system description)
If I assume that off-diagonal entries are 0, I can transform this to the CMS coordinate system
I have no sense of how well Cocoa estimates errors
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3.8T Cocoa ME+1/3 3.8T Cocoa ME+1/3 Chamber CentersChamber Centers
mm, Cocoa errors
X Y Z
ME+1/3_03 5593.20 ± .37 2033.34 ± .31 6864.52 ± .13
ME+1/3_09 1035.73 ± .30 5860.51 ± .38 6863.06 ± .13
ME+1/3_14 -3825.85 ± .25 4558.86 ± .23 6864.59 ± .37
ME+1/3_20 -5861.03 ± .16 -1033.74 ± .30 6867.26 ± .37
ME+1/3_27 -1032.27 ± .30 -5861.44 ± .38 6866.91 ± .13
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Now Compare Cocoa to DDDNow Compare Cocoa to DDD
Cocoa errors and chamber mismounts both contribute to this
Remove overall disk rotation and translation to get a picture of the internal shifting
Only 6 chambers available for ME+1/2
Only 5 chambers for ME+1/3 (PT6 bad)
Does NOT display chamber tilts
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ExpectExpect
Z shift of ring due to disk bending will be gone
Rotation of disk will be gone
Chamber mismounting, sensor mismeasure, and Cocoa fit error will remain
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ME+1/3 deviation changes with fieldME+1/3 deviation changes with field
5 measured centers
Overall rotation and translation is removed
No more than a few dozen microns difference between the patterns found with field off and field onMax dev =1.6mm
Animated
cm
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Cocoa EstimatesCocoa Estimates
Cocoa vs Ideal deviation RMSs are comparable to and smaller than (on the average) PG vs Ideal deviation RMSs: next slide’s tableCocoa better than PG?
Deviation averages aren’t always 0 because of missing measurements
BUT
Cocoa may be biased to finding things close to the ideal, since the ideal geometry is one of the inputs!
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““Cocoa(0T) vs Ideal” Cocoa(0T) vs Ideal” vsvs “PG vs Ideal” “PG vs Ideal”Variation of DeviationsVariation of Deviations
Cocoa Cocoa PG Apin PG Apin
ME+1/2 ME+1/3 ME+1/2 ME+1/3
X devs 0 ± 1.2 0 ± 0.8 0 ± 0.7 0 ± 0.8
Y devs 0.1 ± 0.7 0.2 ± 0.6 0.2 ± 0.9 1.1 ± 1.5
Z devs 0 ± 0.4 -0.5 ± 0.8 3.1 ± 6.0 1.8 ± 5.5
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Check for BiasCheck for Bias
Create a new 0T SDF file using PG measurements instead of Ideal geometry as the starting point for chamber positions
Compare fits from this special run to the normal 0T run
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ME+1/3 0T Cocoa fits using PG startME+1/3 0T Cocoa fits using PG start
ME+1/3_03 5595.34 2033.7 6866.29
ME+1/3_09 1035.84 5860.48 6863.06
ME+1/3_14 -3826.75 4559.44 6864.58
ME+1/3_20 -5863.59 -1034.74 6869.03
ME+1/3_27 -1032.91 -5863.23 6870
ME+1/3_33 4558.73 -3827.16 6875.77
X Y Z
James N. Bellinger 20-March-2009
“Chi2” for ideal is 1593, special is 1643 for 866 “dof”
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Special 0T – normal 0TSpecial 0T – normal 0T
X Y Z
ME+1/3_03 2.13 0.39 0.01
ME+1/3_09 0 0 0
ME+1/3_14 -0.76 0.73 0.13
ME+1/3_20 -2.64 -0.7 0.31
ME+1/3_27 -0.39 -1.86 -0.01
ME+1/3_33 0.52 -0.66 -0.01
PG notavailable
James N. Bellinger 20-March-2009
Rms=.15
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Special 0T – normal 0T: notesSpecial 0T – normal 0T: notes
• The difference between using PG and Ideal geometry as a starting point has little effect on the Z fit: 10 microns in most places
• HSLM2 did not have good PG measurements for the alignment pins, so the Special run used Ideal measurements
• X and Y are not well constrained without the presence of the Transfer Lines.
• The fact that the Z measurement is bad at PT6 is irrelevant to this comparison, which studies fit stability
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• Special 3.8T– Endcap data from 3.8T
– Initial chamber and transfer plate positions from PG
– Link and MAB fit geometry and data for 3.8T
5’th Cocoa Run5’th Cocoa Run
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3.8T Fit Using Initial 3.8T Fit Using Initial Chamber Positions from Apin PGChamber Positions from Apin PG
X Y Z
ME+1/3_03 5595.336 2033.726 6864.532
ME+1/3_09 1035.726 5860.509 6863.053
ME+1/3_14 -3826.607 4559.585 6864.728
ME+1/3_20 -5863.667 -1034.446 6867.583
ME+1/3_27 -1032.655 -5863.300 6866.901
ME+1/3_33 4559.190 -3826.700 6866.523
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Special 3.8T – Original 3.8TSpecial 3.8T – Original 3.8T
X Y Z
ME+1/3_03 2.136 0.388 0.016
ME+1/3_09 -0.003 0.000 -0.002
ME+1/3_14 -0.759 0.725 0.134
ME+1/3_20 -2.638 -0.703 0.319
ME+1/3_27 -0.385 -1.865 -0.012
ME+1/3_33 0.099 -1.085 -0.917
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Cloud on the horizon:Cloud on the horizon:ME+1/2 chamber Z centersME+1/2 chamber Z centers
Fits My B=0 Celso B=0 Diff B=0 My B=3.8 Celso B=3.8
Diff B=3.8
ME+1/2_02 6770.64 6771.40 .76 6762.40 6763.18 .78
ME+1/2_08 6768.94 6769.58 .64 6761.59 6762.21 .62
ME+1/2_14 6768.55 6769.15 .60 6761.74 6762.28 .54
ME+1/2_20 6771.95 6771.75 -.20 6763.72 6763.46 -.26
ME+1/2_26 6775.25 6775.54 .29 6766.58 6766.84 .26
ME+1/2_32 6774.78 6774.91 .13 6765.82 6765.97 .15
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Not sure yet
Change with field is the same
Why the difference?Why the difference?
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ConclusionsConclusions
Cocoa fit for ME+1/3 chambers is stable with respect to initial conditions in Z
Photogrammetry includes spurious outliers
Cocoa deviations from the ideal are tighter than PG deviations, even if PG values were the starting point
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Blessing for ME+1/3 chamber ZBlessing for ME+1/3 chamber Z
0T Pos mm 0T Tilt mrad 3.8T Pos mm
3.8T Tilt mrad
ME+1/3_03 6866.29 -0.5 6864.532 1.53
ME+1/3_09 6863.06 -0.83 6863.053 1.99
ME+1/3_14 6864.58 -1.14 6864.728 1.09
ME+1/3_20 6869.03 0.41 6867.583 2.63
ME+1/3_27 6870 -1.93 6866.901 -0.69
Average 6866.59 -0.8 6863.36 1.3
Δ from nominal
-0.85mm -0.8mrad -4.08mm 1.3mrad
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Evaluate the PGEvaluate the PG
Photogrammetry errors for the Z of the alignment pins are not 300μ
Loveless says the pins were not inserted to nominal depth
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• Targets on DCOPS (not used in next slide)
• Targets on alignment pins
• Coded targets on chambers
• Use alignment pins to define chamber axis
• Use X/Y of coded target to predict a Z
• Compare predicted w/ measured Z
PG targets on chambersPG targets on chambers
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Coded Target Z – Predicted ZCoded Target Z – Predicted Z
mm
ME+1/3 chambers
Alignment pins used to predict Z of coded target given its X/Y
Rms=1.4mm
Looks like a single distribution, NOT a narrow one with a few typos
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• Oleg says some were on wrong chambers
• Use his corrected table
• Look at deviation of coded target from alignment pin axis line
• Nothing looks badly wrong; largest deviation is 145mm from axis (min 75mm)
Crosscheck coded targetsCrosscheck coded targets
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DCOPS targetsDCOPS targets
DCOPS on Transfer Plate, chamber 3 outer and chamber 3 inner have three 1.27mm PG targets on top.
These were included in the survey.
In the following table the three measurements were averaged for each of the 18 visible DCOPS
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Variation of PG Z for DCOPSVariation of PG Z for DCOPS
Ref Ave
Ref Rms
3 out Ave
3 out Rms
3 in Ave
3 in Rms
HSLM1 -818.627 0.169 -819.137 0.097 -818.447 0.193
HSLM2 -821.44 0.037 -826.92 0.385 -820.46 0.198
HSLM3 -819.437 0.054 -820.387 0.067 -818.577 0.197
HSLM4 -817.093 0.040 -818.067 0.099 -817.37 0.169
HSLM5 -823.65 0.082 -831.597 0.737 -819.617 0.148
HSLM6 -819.76 0.092 -822.547 0.238 -818.847 0.302
PG target position 3-point ave/rmsJames N. Bellinger 20-March-2009
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DCOPS PG Variation Along LineDCOPS PG Variation Along Line
HSLM1
HSLM2
HSLM3
HSLM4
HSLM5
HSLM6
Ave Z Rms Z
-818.737 0.292233
-822.94 2.842581
-819.467 0.739234
-817.51 0.409507
-824.954 4.977033
-820.384 1.573732
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Evaluation of DCOPS targetsEvaluation of DCOPS targets
Consistency of measurement:The Transfer Plate DCOPS are measured
significantly better than the rest
HSLM5 outer DCOPS are not very consistent
Consistency along line:Chamber mounting variations contribute!
HSLM2 and HSLM5 show unreasonably large fluctuations
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Chamber surface Z’s from PGChamber surface Z’s from PG
Apin outer
Apin inner Coded
DCOPS 3 outer
DCOPS 3 inner Diff outer Diff inner
HSLM1 -696.47 -696.93 -697.44 -697.497 -696.807 -1.02667 0.123333
HSLM2 NA -697.98 -699.06 -705.28 -698.82 NA -0.84
HSLM3 -696.89 -696.3 -698.39 -698.747 -696.937 -1.85667 -0.63667
HSLM4 -694.78 -695.64 -696.72 -696.427 -695.73 -1.64667 -0.09
HSLM5 -699.15 -697.15 -699.21 -709.957 -697.977 -10.8067 -0.82667
HSLM6 -700.4 -696.53 -697.45 -700.907 -697.207 -0.50667 -0.67667
Rms=.53 Rms=.37James N. Bellinger 20-March-2009
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Z’s from PG vs dataZ’s from PG vs data
• HSLM5 outer chamber 3 DCOPS measurements are clearly out of line
• The DCOPS readings from HSLM5 correspond to corrected values shown at right.– Not much variation
XFer 3 Out 3 In 2
18.98 16.72 17.10 18.26
mm, corrected data values
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PG ConclusionsPG Conclusions
Assuming the Alignment pin and coded target errors are comparable, the variation on these is 1mm and not 300 microns.If coded error=300μ, Apin error is 2mm
If the variation is due to random errors: for a DCOPS target atTransfer Plate: 140μOuter chamber edge: 470μInner chamber edge:350μ
Disregard PG measures with large disagreements with either other PG measurements or with data?
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DisplaysDisplays
Omitting lines illustrating chamber surfaceTriangles show the slope well enough
PG information not displayedDiagram is very cluttered already
HSLM1-5 are animated to show 0 to 3.8T shifts
HSLM6 has bad data for the DCOPS at 3.8T and bad Z information for the distancemeter
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Chamber surface estimates
Red=RealGreen=Sim
MAB ASPD
ME12 ASPD
ASPD P4
Distancemeter and dists
IR target
DCOPS dowels
Animated
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Animated
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Animated
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Animated
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Animated
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3.8T is bad
IR target obscured, Z is bad
James N. Bellinger 20-March-2009
48James N. Bellinger 20-March-2009
Animated
49James N. Bellinger 20-March-2009
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53James N. Bellinger 20-March-2009
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Blessing for ME+1/3 chamber ZBlessing for ME+1/3 chamber Z
0T Pos mm 0T Tilt mrad 3.8T Pos mm
3.8T Tilt mrad
ME+1/3_03 6866.29 -0.5 6864.532 1.53
ME+1/3_09 6863.06 -0.83 6863.053 1.99
ME+1/3_14 6864.58 -1.14 6864.728 1.09
ME+1/3_20 6869.03 0.41 6867.583 2.63
ME+1/3_27 6870 -1.93 6866.901 -0.69
Average 6866.59 -0.8 6863.36 1.3
Δ from nominal
-0.85mm -0.8mrad -4.08mm 1.3mrad
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BACKUPMATERIAL
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Method for Predicting Z from PGMethod for Predicting Z from PG
Get PG (X,Y,Z) wrt disk center from UR-0058 or UR-0103
Rotate disk as specified in UR-0124
Translate disk as specified in UR-0124
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PG IssuesPG Issues
Photogrammetry is not always correct
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PG errors and chamber mismountsPG errors and chamber mismounts
PG deviations from Ideal include 1. PG error, typos, and wrong targets
2. Real chamber mismount
3. Overall shifts and rotations of the disk
Subtract the overall shifts and rotations to get a better picture of the PG errors and mismount errors
In what follows PG Chamber centers are derived from alignment pin locations
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PG vs DDD, ME+1/2PG vs DDD, ME+1/2
Chamber centers
Overall rotations and translations are removed
Deviations combine PG error and chamber mounting
cm
Max x/y dev is 2.2mm
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PG vs DDD, ME+1/3PG vs DDD, ME+1/3
Chamber centers
Overall rotations and translations are removed
Deviations combine PG error and chamber mounting
cm
Max x/y dev is 2.6mm
Still a tilt?
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PG to DDD summaryPG to DDD summary
Deviation of PG from standard geometry in the X/Y plane is at most 2.2mm for ME+1/2 and 2.6mm for ME+1/3.
RMS for X deviations is .7 for ME+1/2
.8 for ME+1/3
RMS for Y deviations is.9 for ME+1/2
1.5 for ME+1/3
RMS for Z is about 6. and 5.5mm
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Z’s from PG vs dataZ’s from PG vs data
• The HSLM6 outer Z seems out of line with the rest in the line, but agrees with the alignment pin estimate
• Data shows O(4mm) deviation at 3 Outer also
• PG deviation is OK
XFer 3 Out 3 In 2
18.32 15.79 21.32 23.45
mm, corrected data values
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Comparisons of Ideal with Cocoa Comparisons of Ideal with Cocoa RingsRings
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0T ME+1/2 Cocoa vs Ideal0T ME+1/2 Cocoa vs Ideal
6 measured centers
Overall rotation and translation is removed
cm
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0T ME+1/3 Cocoa vs Ideal0T ME+1/3 Cocoa vs Ideal
5 measured centers
Overall rotation and translation is removed
cm
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3.8T ME+1/2 Cocoa vs Ideal3.8T ME+1/2 Cocoa vs Ideal
6 measured centers
Overall rotation and translation is removed
cm
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3.8T ME+1/3 Cocoa vs Ideal3.8T ME+1/3 Cocoa vs Ideal
5 measured centers
Overall rotation and translation is removed
cm
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