1. University of Wisconsin-Madison
Endcap Notes
James N. Bellinger
University of Wisconsin-Madison
5-August-2010
James N. Bellinger 5-Aug-2010

2. Comparison w/ track-based
Direct comparison is slightly misleading
Correlations not simple
Can compare PseudoRPhi
No track-based sensitivity to Z
No hardware sensitivity to PseudoR (along SLM)
Let ring float for best fit to hardware positions
Let transfer plates float (only know by PG)
James N. Bellinger 5-Aug-2010

3. Comparison w/ track-based
Track-based connects
chambers in rings
Hardware connects
chambers along
lines
Lines are fixed wrt
each other by PG
Let rings float
Let transfer plates float
James N. Bellinger 5-Aug-2010

4. Fit allowing transfer plates to move
Fit to minimize track-hardware chamber center residuals in Pseudo-Rphi, letting SLMs float
Fit moves SLM centers by an average of 0.6mm, with an rms of 1.2mm
Expected PG accuracy is about 0.3mm
It rotates the SLM’s by angles with rms of 0.21mrad
About 1.5mm rms shifts in transfer plate phi position
Fit only done for stations with SLMs and 2 rings: No ME4 or ME1
Quoted numbers from last week were not duplicated
James N. Bellinger 5-Aug-2010

5. Fit decreases residual mean and improves RMS of residual
Station/Ring
Raw mean(mm)
Raw rms
Fit mean(mm)
RMS after fit
-2/1
-0.53
1.75
0.40
1.55
-2/2
-0.67
2.50
-.40
1.40
-3/1
-0.19
2.80
-0.16
2.41
-3/2
0.19
0.47
0.16
0.98
2/1
0.90
0.93
0.50
1.08
2/2
1.86
2.21
-0.50
1.17
3/1
-1.23
2.39
0.09
2.38
3/2
-0.84
-0.09
0.87
Except here
James N. Bellinger 5-Aug-2010

6. Further work Not at 0.6mm level
It ought to be
Use variant of Oleg’s fit instead of Cocoa
Compare to PG instead of tracking
James N. Bellinger 5-Aug-2010

7. BACKUP
Histograms of raw residuals track- hardware and residuals after the fit
James N. Bellinger 5-Aug-2010

8. PseudoRPhi Comparison by ring: ME+2 and ME+3
Raw residuals
ME+2
ME+3
Ring 1
Ring 2
James N. Bellinger 5-Aug-2010

9. PseudoRPhi Comparison by ring: ME+2 and ME+3
Fit residuals
ME+2
ME+3
Ring 1
Ring 2
James N. Bellinger 5-Aug-2010

10. PseudoRPhi Comparison by ring: ME-2 and ME-3
Raw residuals
ME+2
ME+3
Ring 1
Ring 2
James N. Bellinger 5-Aug-2010

11. PseudoRPhi Comparison by ring: ME-2 and ME-3
Fit residuals
ME+2
ME+3
Ring 1
Ring 2
James N. Bellinger 5-Aug-2010

12. PseudoRPhi: No change in residual with increasing radius
Raw residuals
Fit residuals
Ring 1
Ring 2
James N. Bellinger 5-Aug-2010