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Cocoa ME+1 vs PG. James N. Bellinger University of Wisconsin-Madison 2-March-2009. Data used. 0T Distancemeter 16-Nov average DCOPS 11-Nov event Link from Celso 3.8T Distancemeter 1-4 Nov average DCOPS 27-Oct event Link from Celso PG
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Cocoa ME+1 vs PG James N. Bellinger University of Wisconsin-Madison 2-March-2009
James N. Bellinger 2-March-2009 Data used • 0T • Distancemeter 16-Nov average • DCOPS 11-Nov event • Link from Celso • 3.8T • Distancemeter 1-4 Nov average • DCOPS 27-Oct event • Link from Celso • PG • PG within disk UR-0058 (2006) (Oleg cleaned it up) • Supplementary UR-0103 (2008) • PG of disk UR-0124 (after Craft)
Chamber center Z deviations 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 Z deviations Cocoa 3.8T and 0T vs Ideal Cocoa 3.8T Cocoa 0T Cocoa Ideal Ideal fit uses ideal geom and nominal measurements
Fit Ring (average of all chambers) Position Deviations from Ideal James N. Bellinger 2-March-2009
Cocoa Fit Ideal vs DDD • Only 6 entries. Cocoa Ideal minus DDD geometry • Ring 3 only • TODO: where did 8.415mm come from James N. Bellinger 2-March-2009
ME+1/3 chamber tilts (mrad) 0T 3.8T 3.8T-0T At disk top At disk bottom Tilts (mrad) determined from DCOPS Z positions at upper and lower ends of each chamber
James N. Bellinger 2-March-2009 Method 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
PG targets and Cocoa 0T Fits:Z of DCOPS dowels Uses the DCOPS PG targets to predict the DCOPS dowel positions for the Xfer DCOPS and the ME+1/3 DCOPS Different target holders at ME+1/3/09_outer and ME+1/3/27_outer??Inconsistent
James N. Bellinger 2-March-2009 DCOPS from PG and Cocoa 0T FitSummary • DCOPS Dowel positions: 0T Cocoa fit – predicted from PG • Transfer: mean=0.67, rms=2.29mm • 1/3_outer: mean=2.93, rms=3.83mm • 1/3_inner: mean=-0.20, rms=1.37mm • HSLM6 is not included • RMS is large, and at least partly attributable to PG problems
James N. Bellinger 2-March-2009 Deviations 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
James N. Bellinger 2-March-2009 Cocoa 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
3.8T Cocoa 1/3 Chamber Centers James N. Bellinger 2-March-2009
James N. Bellinger 2-March-2009 PG errors and chamber mismounts • PG deviations from Ideal include • PG error, typos, and wrong targets • Real chamber mismount • 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
James N. Bellinger 2-March-2009 PG vs DDD, ME+1/2 Chamber centers Overall rotations and translations are removed Deviations combine PG error and chamber mounting Max x/y dev is 2.2mm cm
James N. Bellinger 2-March-2009 PG vs DDD, ME+1/3 Chamber centers Overall rotations and translations are removed Deviations combine PG error and chamber mounting Max x/y dev is 2.6mm Still a tilt? cm
James N. Bellinger 2-March-2009 PG 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
James N. Bellinger 2-March-2009 Now 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
James N. Bellinger 2-March-2009 Expect • 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
James N. Bellinger 2-March-2009 ME+1/3 deviation changes 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 on Animated cm
James N. Bellinger 2-March-2009 Cocoa Estimates • Cocoa vs Ideal deviation RMSs are comparable to and smaller than (on the average) PG vs Ideal deviation RMSs: next slide’s table • Cocoa 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!
“Cocoa(0T) vs Ideal” vs “PG vs Ideal”Variation of Deviations James N. Bellinger 2-March-2009
James N. Bellinger 2-March-2009 Check 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
James N. Bellinger 2-March-2009 ME+1/3 0T Cocoa fits using PG start X Y Z
James N. Bellinger 2-March-2009 Special 0T – normal 0T X Y Z PG not available
James N. Bellinger 2-March-2009 Special 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
3.8T Initial Chamber Pos from PG James N. Bellinger 2-March-2009
Special 3.8T – Original 3.8T James N. Bellinger 2-March-2009
James N. Bellinger 2-March-2009 Conclusions • 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
Blessing for ME+1/3 chamber Z? James N. Bellinger 2-March-2009
James N. Bellinger 2-March-2009 TODO • Slide comparing alignment pin PG to coded target PG to DCOPS PG • Include pictures of system SLM by SLM • Outer Laser position/direction not reasonable • But Cocoa intersections with CCD seem OK • Z-sensor dowel not cleanly matched to distance • No labels • Not complete • Very hard to understand the current pictures: both cluttered and obscure
James N. Bellinger 2-March-2009 Evaluate the PG • Photogrammetry errors are not 300μ
James N. Bellinger 2-March-2009 DCOPS 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
Variation of PG Z for DCOPS PG target position 3-point ave/rms James N. Bellinger 2-March-2009
James N. Bellinger 2-March-2009 DCOPS PG Variation Along Line
James N. Bellinger 2-March-2009 Evaluation 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
James N. Bellinger 2-March-2009 Coded Target Z – Predicted Z ME+1/3 chambers Alignment pins used to predict Z of coded target given its X/Y Variation exceeds 425microns Looks like single distribution, NOT a narrow one with a few typos mm
Chamber surface Z’s from PG James N. Bellinger 2-March-2009
Z’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. No 10mm shift present mm, corrected data values James N. Bellinger 2-March-2009
Z’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 mm, corrected data values James N. Bellinger 2-March-2009
James N. Bellinger 2-March-2009 PG Conclusions • Assuming the Alignment pin and coded target errors are comparable, the variation on these is 1mm and not 300 microns. • If the variation is due to random errors: for a DCOPS target at • Transfer Plate: 140μ • Outer chamber edge: 470μ • Inner chamber edge: 350μ • Other option is to disregard PG measures with large disagreements with either other PG measurements or with data
Distancemeter and dists Chamber surface estimates DCOPS dowels Laser is wrong somehow Red=Real Green=Sim ME12 ASPD IR target MAB ASPD ASPD P4 James N. Bellinger 2-March-2009
3.8T is bad IR target obscured, Z is bad James N. Bellinger 2-March-2009
James N. Bellinger 2-March-2009 • BACKUP • MATERIAL
James N. Bellinger 2-March-2009 0T ME+1/2 Cocoa vs Ideal 6 measured centers Overall rotation and translation is removed cm
James N. Bellinger 2-March-2009 0T ME+1/3 Cocoa vs Ideal 5 measured centers Overall rotation and translation is removed cm