1. University of Wisconsin-Madison
Transfer Lines
James N. Bellinger
University of Wisconsin-Madison
26-June-2009
James N. Bellinger 26-June-2009

2. Transfer Lines: Positions
of 12 DCOPS
Lasers at ME+4
and ME-4
shine axially
Establish
relative X,Y
of the transfer
plates, and thus
the SLM ends
SLM example Y X
James N. Bellinger 26-June-2009

3. DCOPS along Transfer Lines
Mounted on MABs
Minus Endcap
Plus Endcap
CMS Z
Endcap DCOPS are mounted to the disks
James N. Bellinger 26-June-2009

4. CRAFT Results
The laser direction control program failed. Only one half of one Transfer Line was complete
Each side has a crosshair laser pair. Only one of each pair threaded across completely
Impossible to fit Transfer Lines.
James N. Bellinger 26-June-2009

5. Data from Complete Transfer Line
Taken at 05:40 23-June
Lasers thread through
Leave out MAB stations for the time being
Fit and look for disk positions
James N. Bellinger 26-June-2009

6. Limitations
MAB positions do not measure YB disks w/o additional information
Transfer Plate calibrations are not included here
James N. Bellinger 26-June-2009

7. Cocoa Fit: Both lasers, both endcaps, YE+3 and YE-3 fixed
Name
X shift (mm)
Y shift (mm)
Zrot (mrad)
YE+1
-2.17
1.16
0.38
YE+2
-0.59
-0.05
0.67
YE+3
0 (fixed)
YE-1
-1.66
0.00
YE-2
0.21
-0.34
-0.53
YE-3
23-June
All lasers done
Name
X shift (mm)
Y shift (mm)
Zrot (mrad)
YE+1
-1.73
1.72
0.29
YE+2
-0.38
0.38
0.62
YE+3
0 (fixed)
YE-1
-2.82
0.49
-0.01
YE-2
-0.05
0.54
-0.69
YE-3
Compare:
17-June
2 lasers done
James N. Bellinger 26-June-2009

8. Cocoa Fit: Both lasers, both endcaps, YE+3 fixed
Name
X shift (mm)
Y shift (mm)
Zrot (mrad)
YE+1
-1.68
1.62
0.47
YE+2
-0.35
0.16
0.72
YE+3
0 (fixed)
YE-1
0.65
2.07
0.45
YE-2
2.77
2.00
-0.03
YE-3
2.81
2.57
0.59
23-June
All lasers done
Name
X shift (mm)
Y shift (mm)
Zrot (mrad)
YE+1
-0.47
1.00
0.28
YE+2
0.01
0.62
YE+3
0 (fixed)
YE-1
3.29
-2.27
-0.09
YE-2
6.70
-2.52
-0.78
YE-3
7.33
-3.37
-0.10
Compare:
17-June
2 lasers done
James N. Bellinger 26-June-2009

9. Average Data over 9 events
Name
X shift (mm)
Y shift (mm)
Zrot (mrad)
YE+1
(-2.17)
0.31 (1.16)
0.33 (0.38)
YE+2
-1.12 (-0.59)
-0.10 (-0.05)
0.76 (0.67)
YE+3
0 (fixed)
YE-1
-1.81 (-1.66)
-1.11 (-0.05)
0.16 (0.00)
YE-2
-0.42 (0.21)
(-0.34)
-0.49 (-0.53)
YE-3
YE+3/YE-3 fixed
Name
X shift (mm)
Y shift (mm)
Zrot (mrad)
YE+1
-0.03 (-1.68)
0.44 (1.62)
0.37 (0.47)
YE+2
-0.67 (-0.35)
-0.05 (0.16)
0.79 (0.72)
YE+3
0 (fixed)
YE-1
2.19 (0.65)
-0.55 (2.07)
0.32 (0.45)
YE-2
4.08 (2.77)
-0.20 (2.00)
-0.31 (-0.03)
YE-3
4.80 (2.81)
0.66 (2.57)
0.22 (0.59)
RED: single event
only: compare
YE+3 only
fixed
James N. Bellinger 26-June-2009

10. What’s wrong? Is it fixable?
Shadowing is not a huge problem: paired redundant CCDs mean the other one is OK
Non-optimal filters
Nothing we can do about this now
Relative only; no CMS reference yet
Residuals aren’t good
Investigating
Fit stability for positions not wonderful
Partly a function of 4) above
Partly readout glitch issue (investigating)
James N. Bellinger 26-June-2009

11. Geometry needs work Using PG positions for transfer
plates relative to the disks
WORSE!
Using ideal geometry for
transfer plate positions
relative to the disks
DCOPS residuals
James N. Bellinger 26-June-2009

12. Plans
Use Link fits and sensors in ME1/2 and the outer MABs to get CMS reference X/Y
Define DCOPS wrt MABs and MABs wrt tracker to pin down relative positions
Understand why large residuals (RMS=3.7mm) !!
James N. Bellinger 26-June-2009

13. BACKUP MATERIAL
James N. Bellinger 26-June-2009

14. Profile with no major variation
Highest profile is
plotted first. Green
dotted is usually
last, unless it was
highest, in which
case red dotted
was last to be
plotted.
Whatever was first is
usually impossible
to see because later
plots obscure it.
James N. Bellinger 25-June-2009

15. Variation in laser Intensity
in peak height
James N. Bellinger 26-June-2009

16. Known laser profile problem
James N. Bellinger 26-June-2009

17. Known Profile Problem Odd coincidence that both beams
are similarly bad
James N. Bellinger 26-June-2009

18. Laser Drift with time Position shifts by about 1mm
More of an opportunity than a
problem: lets us check fit stability
James N. Bellinger 26-June-2009

19. Ideal View From Crosshair Laser
James N. Bellinger 26-June-2009

20. Real World
James N. Bellinger 26-June-2009

21. Shadowing of One CCD Leaves Other CCD OK
17-June data
James N. Bellinger 26-June-2009