Comparing Laser Fit to Barrel Fit University of Wisconsin-Madison James N. Bellinger University of Wisconsin-Madison 12-August-2011 V1.1 James N Bellinger UW Madison

Validation Exercise Fix Transfer Lines using positions at MAB3 Predict DCOPS centers all along the lines Compare my prediction with Barrel inner MAB DCOPS centers Examine predictions of ME station positions for sanity Two possible sources for MAB3 Barrel fit (more likely to be self-consistent w/ MAB1?) Link fit (use z-bar fit) How are these related? 24 February 2019 James N Bellinger UW Madison

Description of Part 1 Study “radial” direction for DCOPS: insensitive to rotations, and “tangential” directions which are Centers change radius with field, but should be symmetric Plus/Minus ABANDON THIS ASSUMPTION! Rely on MAB3 Given PG MAB calibration, find DCOPS center wrt MAB center Use the Barrel fit for MAB center and orientation to calculate the DCOPS center position for all MABs Anchor my laser line fits using the Barrel MAB3 DCOPS Centers from 4 Calculate “radial” positions for all other DCOPS Compare MAB1 Barrel fit position w/ my prediction My fit does not include MAB1 Barrel information: independent 24 February 2019 James N Bellinger UW Madison

Schematic of my fit Calculate relative offsets and add to the line through MAB3 points Compare w/ Barrel fit Fixed relative offset=0 Barrel fit radius used Calculation uses average profile position at center of DCOPS—no tilt MAB+3 MAB-3 Given profile centers for both lasers, fit for laser lines and DCOPS offsets 24 February 2019 James N Bellinger UW Madison

Predicted radius - Barrel radius 0.56mm systematic shift RMS=0.27mm! Very tight distribution Why the offset? 24 February 2019 James N Bellinger UW Madison

My Predicted – Barrel Tangential Fit for MAB1 Again an offset; 1.2mm= 2x the radial RMS is better than earlier analyses, but not as good as radial Rotation about CMS-Z? 24 February 2019 James N Bellinger UW Madison

My Predicted – Barrel Tangential Fit details Difference of differences is almost the same at each line, (modulo sign change)! Strongly suggests calculation artifact somewhere 24 February 2019 James N Bellinger UW Madison

Part 2 Compare the predicted DCOPS positions on the different stations Look for bulk shifts corresponding to disk movement Look for bending in YE+2 and YE-2 Should be similar Look for Rphi agreement ME3 and ME2 Should be that same Need to include PG offsets wrt the ideal for transfer plates to do this correctly—not done yet 24 February 2019 James N Bellinger UW Madison

Predicted radius - Barrel radius MAB+1 MAB+1 and MAB-1 have consistent mean and RMS (MAB+1/Line5 MAB did not read out) MAB-1 24 February 2019 James N Bellinger UW Madison

ME+4 – ME-4 Coords VS Phi ME+4 – ME-4 Vertical (radius) and Horizontal (tangent) Clear pattern: YE+3 is shifted wrt YE-3 by O(5.5mm) (Transfer Plate mounting corrections NOT included) 24 February 2019 James N Bellinger UW Madison

YE+3 vs YE+2 ME+4 vs ME+2 Very clearly YE+3 is shifted wrt YE+2 by O(5.1mm) 24 February 2019 James N Bellinger UW Madison

Consistency at/between YE+2 YE-2 Fair agreement YE2 bending: Expect ME3-ME2 radius O(-4): OK variation in horiz O(.2): not dR=-5.7±1.3 dRPhi=-1.2±.9 dR=-3.9±.6 dRPhi=-1.5±.4 PG variation in mounting O(1.5) 24 February 2019 James N Bellinger UW Madison

Repeat Using Link for MAB3 Still use barrel for MAB1 Some MAB rotations are default values The fit is exactly the same—the only thing that changes are the points I use to anchor the DCOPS line. This uses the Link fit to MAB3 instead of the Barrel fit. 24 February 2019 James N Bellinger UW Madison

Link-based MAB3: MAB1 Radial Differences Line 4 looks bad. If I omit it, the mean =0.47 RMS =0.71 Compare w/slide 5 mean =0.56 RMS =0.27 Consistent Remember: I use defaults for some Link MAB params 2/24/2019 James N Bellinger UW Madison

Using Link Data to fix Prediction Line: Horizontal coordinates Looks worse: See Slide 6 Here: mean=-1.80 RMS=1.27 Before: mean=-1.22 RMS=0.71 Consistent 24 February 2019 James N Bellinger UW Madison

Looking for Artifacts in Link-fixed Tangential Predictions Line 6 is out of line with the rest. Most show about 1mm between residuals, as before—but with a new sign pattern. See slide 7 24 February 2019 James N Bellinger UW Madison

Link-fixed Tangential Predictions – Barrel, no Line 6 Without 6, distribution tighter, offset smaller. Compare w/ Slide 15, 6 Here (Link cut): -1.26±0.58 Link uncut (15) -1.8±1.27 Slide 6 (barrel): -1.22±0.71 24 February 2019 James N Bellinger UW Madison

Tentative Conclusions Using MAB3 as fixed points validates the Transfer Line fit at the MAB1 positions at the .7mm RMS level in Rphi and .27mm in radius Link-based MAB3 can be as good as Barrel- based MAB3, perhaps better—but bad measurements can throw us off We see systematic offsets from the Transfer Line prediction to the Barrel measurements, whether we fix the MAB3 using Barrel or Link 24 February 2019 James N Bellinger UW Madison

Not understood yet Why is there a radial offset from the Barrel DCOPS prediction to the Transfer Line prediction? (The precision looks good) Why is there a Rphi offset from the Barrel DCOPS prediction to the Transfer Line prediction? (Precision looks fair) What combination of Link and Barrel MAB3 measurements is best? 24 February 2019 James N Bellinger UW Madison

To Be Done Calculate Transfer Plate PG deviations from ideal in these coordinates and apply to the disk shift/rotation study Explore What might cause a systematic offset in MAB1 What might cause the differences of deviations to cluster (slide 7, 16) Providing Transfer Line fit as additional constraint to Barrel fit Select the correct MAB3 fits to use as input Joint fit to MAB3 and MAB1? Estimate what the error will be in predicting Transfer Plate X/Y positions 2/24/2019 James N Bellinger UW Madison

BACKUP 24 February 2019 James N Bellinger UW Madison

Calculation I use a Pari/gp script, interpreted by the gp program. Not COCOA I know what it is doing Chi-squared calculation rather than fit Arbitrary precision in matrix inversions Generates relative offsets Fast. I used this for producing the position vs time plots to determine if a MAB fall had caused blockage or whether the floor was sagging. Processing a thousand events took hours—Cocoa would have spent days at it. 24 February 2019 James N Bellinger UW Madison

Data Event from 10-June Barrel event 3981 Almost all Transfer Line stations reproducible! Barrel event 3981 MAB+1/9 does not read out; no position fit Calculations done using tools shown in http://www.hep.wisc.edu/~jnb/cms/25Jul2011/index.html 24 February 2019 James N Bellinger UW Madison

Notes Difference between DCOPS center radius and the local “Vertical” coordinate is at most 12 microns, so I don’t worry about it The local DCOPS coordinate center is taken at the ideal position Positive “Horizontal” coordinate is in the direction of positive phi 24 February 2019 James N Bellinger UW Madison