Transcript ppt
Intra-Tower Tracker Alignment
Gamma-ray Large Area
Space Telescope
Michael Kuss
INFN Pisa
Instrument Analysis Workshop 4
SLAC
15 July 2005
Towers …
the ideal tower
a horizontal shift
a vertical shift
a rotation
the real tower
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Class Residual
Class Residual is used for alignment:
Residual(const TString="MyRootFile.root", const TString="residual.root",
const TString geo="");
~Residual() { delete myEvent; delete myTracker; }
void Go(int lastEntry=-1);
// general for DrawXxx: residual is h_abs - h_abs_ext
// ***********
// draws the residual, top without fitting, bottom with gauss fit
void DrawResidual(TString plane, TCut="");
// draws top the slope vs. residual, bottom the profile with pol1 fit
void DrawResSlope(TString plane, TCut="");
// draws top the other coordinate vs. residual, bottom profile with pol1 fit
void DrawResOrd(TString plane, TCut="");
// draws the slope profiles for all planes
void DrawResSlopeAll(TCut="abs(h_abs_ext-h_abs)<1");
// draws the ordinate profiles for all planes
void DrawResOrdAll(TCut="abs(h_abs_ext-h_abs)<1");
// attempt to do a "statistical" (not event be event) correction of rotZ of
// planes. 2x3 histograms. Left uncorrected, right rotZ corrected. Top
// ordinate vs. residual, middle profile of that, bottom residual.
void DrawResOrdCorr(TString plane, TCut="");
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
What does it do?
aligns planes horizontally, along the measured coordinate
aligns planes vertically
does an estimate of the rotation around z
What does it not do?
doesn’t align planes horizontally, parallel to the strips
doesn’t determine rotations around x and y
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
General Procedure
user> source cmt/setup.sh
user> rh9_gcc32opt/runTreeMaker.exe digi.root recon.root ”” tree.root
user> root
root [0] .x compile.C
root [1] Residual* r = new Residual(”tree.root”,”res.root”,”geo.txt”)
… opens tree.root for reading, res.root for writing, and reads the geometry from
geo.root.
root [2] r->Go()
... reads events from the tree file. Fits a straight tracks, discarding the clusters of both planes
of the tray to which the plane to be studied belongs. For each cluster(!), fills a small tree with
plane name
measured horizontal position of cluster (vertical to the strips)
measured vertical position of cluster (i.e., elevation of the plane)
extrapolated horizontal position of cluster vertical to the strips (track fit)
extrapolated horizontal position of cluster parallel to the strips (track fit in the other view)
inverse slope of track
and saves the small tree in the residual file.
root [3] r->Draw...()
// e.g. r->DrawResSlopeAll()
utilizes one of the Draw... methods. And saves a new geometry to disk.
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
selecting tracks
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Residual
r->DrawResidual(”X5”, ”abs(h_abs-h_abs_ext)<1”)
horizontal displacement: 59m
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Residuals vs. slope (horizontal and vertical
alignment)
r->DrawResSlope(”Y9”, ”abs(h_abs-h_abs_ext)<1&&abs(invSlope)<1”)
θ
real
position
X4
X3
X2
X1
X0
ideal
position
res = x + z · cot(θ)
horizontal displacement: 157m
Aligns:
• horizontal ( to strips)
• vertical
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
vertical displacement: 81m
Michael Kuss
Residuals vs. slope of track (all planes)
r->DrawResSlopeAll()
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Residuals vs. position in other view
r->DrawResOrd(”Y9”, ”abs(h_abs-h_abs_ext)<1”)
X
Y, ideal position
horizontal displacement: 65m
rotation around z: 0.54mrad
Y, real position
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Residuals vs. position in other view (all planes)
r->DrawResOrdAll()
r->DrawResOrdCorr(”Y9”)
res_x%y
11
res_x-p0-y*p1%y
Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Alignment results
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
-0.1
-0.2
-0.3
-0.4
-0.5
-0.6
-0.7
-0.8
dz
drotz
dh
Y0
X0
X1
Y1
Y2
X2
X3
Y3
Y4
X4
X5
Y5
Y6
X6
X7
Y7
Y8
X8
X9
Y9
Y10
X10
X11
Y11
Y12
X12
X13
Y13
Y14
X14
X15
Y15
Y16
X16
X17
Y17
difference / mm or mrad
.
difference A_39800573 - Gleam_v5r8
plane
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
How To Align
Alignment is an iterative process.
Before RA v8r3p1:
• run with 10k events till convergence
• run with 20k events till convergence
• run with 50k events till convergence
• run with 100k events till convergence
initially, convergence was defined as maximum deviation of any parameter of two
consecutive geometries to be less than 10μm (but not more than 5 iterations)
1 iteration for 100k events takes about 1h CPU
Since RA v8r3p1:
• run with 100k events till “real” convergence
“reaI” convergence is achieved if a geometry repeats (but not more than 50 iterations)
1 iteration for 100k events takes about 6 min CPU
result is “perfect” geometry
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Alignment: 1st try
0.250
0.225
0.200
0.175
0.150
0.125
0.100
0.075
0.050
0.025
0.000
-0.025
-0.050
-0.075
-0.100
-0.125
-0.150
-0.175
-0.200
-0.225
-0.250
-0.275
-0.300
-0.325
-0.350
-0.375
-0.400
-0.425
-0.450
-0.475
-0.500
-0.525
-0.550
-0.575
-0.600
Y0
X0
X1
Y1
Y2
X2
X3
Y3
Y4
X4
X5
Y5
Y6
X6
X7
Y7
Y8
X8
X9
Y9
Y10
X10
X11
Y11
Y12
X12
X13
Y13
Y14
X14
X15
Y15
Y16
X16
X17
19
17
15
13
11
9
7
5
3
1
19
17
15
13
11
9
7
5
3
1
19
17
15
13
11
9
7
5
3
1
19
17
15
13
11
9
7
5
3
Y17
1
position/mm
Alignment vertical
iteration
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Intra-Tower Alignment Blindness
Attention
Intra-tower alignment is blind versus:
• translation
• shearing
• vertical scaling (horizontal is fixed by strip dimensions)
• rotation
• translation of the planes of one view vs. the other
• rotation of the planes of one view vs. the other
After every iteration, separately in each view, I “correct” for:
• ∑posh = 0 (horizontal translation)
• ∑posh2 min. (shearing)
• ∑(posv-posv,ref) = 0 (vertical translation)
• ∑(posv-posv,ref)2 min. (vertical scaling)
• ∑rotz = 0 (rotation around z)
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Alignment: 3rd try
Alignment vertical
0.100
Y0
X0
0.090
X1
0.080
Y1
Y2
0.070
X2
0.060
X3
Y3
0.050
Y4
0.040
X4
X5
0.030
Y5
position/mm
0.020
Y6
0.010
X6
X7
0.000
Y7
Y8
X8
-0.010
-0.020
X9
-0.030
Y9
-0.040
Y10
-0.050
X10
X11
-0.060
Y11
Y12
-0.070
X12
X13
-0.080
Y13
Y14
X14
-0.090
-0.100
X15
-0.110
Y15
-0.120
Y16
X16
-0.130
X17
-0.140
Y17
19
17
15
13
11
9
7
5
3
1
19
17
15
13
11
9
7
5
3
1
19
17
15
13
11
9
7
5
3
1
19
17
15
13
11
9
7
5
3
1
-0.150
iteration
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
1st 100k
Alignment vertical
0.160
0.140
Y0
X0
X1
Y1
Y2
X2
X3
Y3
Y4
X4
X5
Y5
Y6
X6
X7
Y7
Y8
X8
X9
Y9
Y10
X10
X11
Y11
Y12
X12
X13
Y13
Y14
X14
X15
Y15
Y16
X16
X17
Y17
0.120
0.100
0.080
0.060
0.040
0.020
position/mm
0.000
-0.020
-0.040
-0.060
-0.080
-0.100
-0.120
-0.140
-0.160
-0.180
-0.200
-0.220
-0.240
-0.260
-0.280
Gleam
3
6
9
12
15
18
21
24
27
30
33
36
39
42
45
48
0
3
6
9
12
15
18
21
24
27
30
33
36
39
42
45
48
0
3
6
9
12
15
18
21
24
27
30
33
36
39
42
45
48
0
3
6
9
12
15
18
21
24
27
30
33
36
39
42
45
48
-0.300
iteration
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Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
1st 100k
Alignment vertical
0.065
0.060
-0.085
0.021
0.000
-0.049
-0.025
0.001
0.000
-0.006
0.015
-0.002
-0.020
0.021
0.042
-0.009
-0.011
0.061
0.055
-0.008
0.007
0.049
0.026
0.003
0.000
0.036
0.023
0.005
0.004
-0.004
-0.017
0.010
0.006
-0.039
-0.043
-0.003
-0.005
-0.060
0.055
0.050
0.045
0.040
0.035
0.030
0.025
0.020
position/mm
0.015
0.010
0.005
0.000
-0.005
-0.010
-0.015
-0.020
-0.025
-0.030
-0.035
-0.040
-0.045
-0.050
-0.055
-0.060
-0.065
-0.070
-0.075
-0.080
-0.085
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
-0.090
iteration
23
Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
2nd 100k
Alignment vertical
0.035
0.033
-0.015
0.007
0.032
-0.010
0.000
0.003
0.015
0.021
0.011
-0.001
-0.025
0.006
-0.004
-0.021
-0.015
-0.014
-0.001
-0.009
-0.002
-0.006
0.001
-0.010
-0.012
0.005
0.004
-0.008
0.000
0.016
0.001
0.013
0.018
0.003
0.002
0.017
-0.002
-0.021
0.030
0.028
0.025
0.023
0.020
0.018
0.015
0.013
position/mm
0.010
0.008
0.005
0.003
0.000
-0.003
-0.005
-0.008
-0.010
-0.013
-0.015
-0.018
-0.020
-0.023
-0.025
-0.028
-0.030
-0.033
-0.035
-0.038
-0.040
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
-0.043
iteration
25
Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
3rd 100k
Alignment vertical
0.085
0.080
-0.010
0.074
0.032
-0.005
-0.008
0.008
-0.003
0.015
0.008
-0.013
-0.007
0.010
0.017
-0.031
-0.032
0.010
-0.008
-0.036
-0.042
-0.011
-0.018
-0.029
-0.015
-0.013
-0.009
-0.017
-0.003
0.001
-0.004
0.008
0.024
0.005
0.006
0.045
0.038
0.009
0.075
0.070
0.065
0.060
0.055
0.050
0.045
position/mm
0.040
0.035
0.030
0.025
0.020
0.015
0.010
0.005
0.000
-0.005
-0.010
-0.015
-0.020
-0.025
-0.030
-0.035
-0.040
-0.045
-0.050
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
-0.055
iteration
27
Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
4th 100k
0.053
0.050
0.048
0.045
0.043
0.040
0.038
0.035
0.033
0.030
0.028
0.025
0.023
0.020
0.018
0.015
0.013
0.010
0.008
0.005
0.003
0.000
-0.002
-0.005
-0.007
-0.010
-0.013
-0.015
-0.018
-0.020
-0.023
-0.025
-0.028
-0.030
-0.033
-0.035
-0.038
-0.040
-0.043
-0.045
-0.048
-0.050
-0.053
-0.055
-0.018
-0.031
-0.042
-0.012
-0.002
-0.033
-0.006
0.010
0.021
0.008
0.045
-0.002
0.001
0.013
0.019
0.013
0.006
0.017
0.030
0.001
-0.006
0.022
0.032
-0.012
0.004
0.028
0.013
0.001
0.008
-0.007
-0.032
-0.004
-0.007
-0.048
-0.029
-0.002
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
position/mm
Alignment vertical
iteration
29
Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
5th 100k
Alignment vertical
0.075
0.070
-0.086
0.053
0.056
-0.072
-0.024
0.021
-0.002
0.018
0.068
-0.035
-0.029
0.027
0.045
-0.035
-0.040
0.010
0.028
-0.037
-0.006
0.026
0.042
-0.022
-0.010
0.028
0.007
0.000
-0.007
0.015
0.000
0.012
0.020
-0.015
-0.045
0.038
0.024
-0.071
0.065
0.060
0.055
0.050
0.045
0.040
0.035
0.030
0.025
position/mm
0.020
0.015
0.010
0.005
0.000
-0.005
-0.010
-0.015
-0.020
-0.025
-0.030
-0.035
-0.040
-0.045
-0.050
-0.055
-0.060
-0.065
-0.070
-0.075
-0.080
-0.085
-0.090
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
1
4
7
10
13
16
19
22
25
28
31
34
37
40
43
46
49
-0.095
iteration
31
Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Reproducibility: vertical
plane
Y0
X0
X1
Y1
Y2
X2
X3
Y3
Y4
X4
X5
Y5
Y6
X6
X7
Y7
Y8
X8
X9
Y9
Y10
X10
X11
Y11
Y12
X12
X13
Y13
Y14
X14
X15
Y15
Y16
X16
X17
Y17
33
#0
42.610
44.710
74.402
76.751
106.519
108.935
139.620
141.939
172.693
175.042
205.807
208.114
238.896
241.340
271.278
273.549
303.407
305.911
335.807
338.141
368.078
370.465
400.355
402.788
432.712
435.026
464.999
467.349
497.369
499.649
529.678
532.019
561.970
564.241
594.272
596.707
absolute position / mm
#1
#2
#3
#4
42.581
42.587
42.612
42.605
44.702
44.692
44.701
44.689
74.383
74.373
74.394
74.377
76.743
76.749
76.753
76.750
106.523
106.528
106.523
106.515
108.928
108.925
108.931
108.922
139.630
139.617
139.627
139.619
141.948
141.949
141.932
141.936
172.712
172.719
172.693
172.702
175.053
175.047
175.047
175.056
205.818
205.819
205.816
205.822
208.117
208.117
208.107
208.114
238.890
238.899
238.899
238.897
241.342
241.347
241.332
241.342
271.288
271.295
271.294
271.303
273.548
273.543
273.544
273.546
303.417
303.408
303.418
303.413
305.904
305.928
305.912
305.924
335.809
335.823
335.813
335.822
338.143
338.135
338.137
338.138
368.083
368.074
368.082
368.082
370.464
370.479
370.458
370.467
400.361
400.373
400.353
400.369
402.794
402.778
402.785
402.792
432.729
432.716
432.724
432.724
435.023
435.031
435.018
435.032
465.005
465.004
465.006
465.002
467.353
467.346
467.346
467.349
497.372
497.364
497.366
497.368
499.647
499.648
499.648
499.640
529.682
529.673
529.683
529.674
532.011
532.017
532.014
532.011
561.957
561.975
561.972
561.968
564.234
564.215
564.232
564.218
594.263
594.247
594.271
594.258
596.691
596.712
596.704
596.701
avg
42.599
44.699
74.386
76.749
106.522
108.928
139.623
141.941
172.704
175.049
205.816
208.114
238.896
241.341
271.292
273.546
303.413
305.916
335.815
338.139
368.080
370.467
400.362
402.787
432.721
435.026
465.003
467.349
497.368
499.646
529.678
532.014
561.968
564.228
594.262
596.703
#0-avg
11
11
16
2
-3
7
-3
-2
-11
-7
-9
0
0
-1
-14
3
-6
-5
-8
2
-2
-2
-7
1
-9
0
-4
0
1
3
0
5
2
13
10
4
Instrument Analysis Workshop 4, SLAC, 15 July 2005
deviation / um
#1-avg
#2-avg
#3-avg
#4-avg
-18
-12
13
6
3
-7
2
-10
-3
-13
8
-9
-6
0
4
1
1
6
1
-7
0
-3
3
-6
7
-6
4
-4
7
8
-9
-5
8
15
-11
-2
4
-2
-2
7
2
3
0
6
3
3
-7
0
-6
3
3
1
1
6
-9
1
-4
3
2
11
2
-3
-2
0
4
-5
5
0
-12
12
-4
8
-6
8
-2
7
4
-4
-2
-1
3
-6
2
2
-3
12
-9
0
-1
11
-9
7
7
-9
-2
5
8
-5
3
3
-3
5
-8
6
2
1
3
-1
4
-3
-3
0
4
-4
-2
0
1
2
2
-6
4
-5
5
-4
-3
3
0
-3
-11
7
4
0
6
-13
4
-10
1
-15
9
-4
-12
9
1
-2
STDEV:
6
Michael Kuss
Reproducibility: horizontal
34
plane
Y0
X0
X1
Y1
Y2
X2
X3
Y3
Y4
X4
X5
Y5
Y6
X6
X7
Y7
Y8
X8
X9
Y9
Y10
X10
X11
Y11
Y12
X12
X13
Y13
Y14
X14
X15
Y15
Y16
X16
X17
Y17
#0
-0.064
-0.068
-0.089
-0.070
-0.023
0.129
0.124
0.153
0.153
0.126
0.115
-0.078
-0.042
-0.090
-0.082
-0.052
-0.032
-0.071
-0.119
0.111
0.142
-0.081
-0.108
-0.106
-0.105
0.045
0.035
-0.018
-0.026
0.016
0.005
0.017
0.023
0.072
0.041
0.016
absolute position / mm
#1
#2
#3
#4
-0.062
-0.054
-0.051
-0.053
-0.072
-0.076
-0.070
-0.076
-0.087
-0.097
-0.092
-0.097
-0.070
-0.067
-0.067
-0.068
-0.025
-0.024
-0.025
-0.023
0.134
0.125
0.128
0.129
0.126
0.122
0.126
0.124
0.147
0.149
0.148
0.147
0.147
0.151
0.149
0.149
0.129
0.132
0.129
0.133
0.114
0.119
0.117
0.120
-0.077
-0.080
-0.081
-0.082
-0.040
-0.046
-0.047
-0.046
-0.092
-0.086
-0.089
-0.087
-0.086
-0.075
-0.084
-0.078
-0.048
-0.054
-0.055
-0.053
-0.031
-0.035
-0.035
-0.032
-0.072
-0.064
-0.072
-0.067
-0.121
-0.115
-0.118
-0.117
0.115
0.106
0.109
0.112
0.144
0.142
0.141
0.144
-0.083
-0.077
-0.085
-0.080
-0.105
-0.102
-0.107
-0.104
-0.102
-0.104
-0.104
-0.104
-0.105
-0.105
-0.104
-0.105
0.045
0.045
0.043
0.046
0.034
0.035
0.035
0.037
-0.018
-0.016
-0.015
-0.019
-0.026
-0.026
-0.023
-0.029
0.016
0.011
0.013
0.013
0.004
0.000
0.002
0.002
0.016
0.019
0.019
0.017
0.023
0.025
0.025
0.025
0.074
0.066
0.072
0.071
0.043
0.038
0.046
0.036
0.011
0.019
0.016
0.020
avg
-0.057
-0.072
-0.092
-0.068
-0.024
0.129
0.124
0.149
0.150
0.130
0.117
-0.080
-0.044
-0.089
-0.081
-0.052
-0.033
-0.069
-0.118
0.111
0.143
-0.081
-0.105
-0.104
-0.105
0.045
0.035
-0.017
-0.026
0.014
0.003
0.018
0.024
0.071
0.041
0.016
#0-avg
-7
4
3
-2
1
0
0
4
3
-4
-2
2
2
-1
-1
0
1
-2
-1
0
-1
0
-3
-2
0
0
0
-1
0
2
2
-1
-1
1
0
0
Instrument Analysis Workshop 4, SLAC, 15 July 2005
deviation / um
#1-avg
#2-avg
#3-avg
-5
3
6
0
-4
2
5
-5
0
-2
1
1
-1
0
-1
5
-4
-1
2
-2
2
-2
0
-1
-3
1
-1
-1
2
-1
-3
2
0
3
0
-1
4
-2
-3
-3
3
0
-5
6
-3
4
-2
-3
2
-2
-2
-3
5
-3
-3
3
0
4
-5
-2
1
-1
-2
-2
4
-4
0
3
-2
2
0
0
0
0
1
0
0
-2
-1
0
0
-1
1
2
0
0
3
2
-3
-1
1
-3
-1
-2
1
1
-1
1
1
3
-5
1
2
-3
5
-5
3
0
STDEV:
2
#4-avg
4
-4
-5
0
1
0
0
-2
-1
3
3
-2
-2
2
3
-1
1
2
1
1
1
1
1
0
0
1
2
-2
-3
-1
-1
-1
1
0
-5
4
Michael Kuss
The Future of LeaningTower
•can only analyze single tower runs
•introduces ambiguities for the resulting geometry
•doesn’t iterate on rotations
•people don’t like it anyway
merge with AlignmentContainer
35
Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Intra-Tower Alignment Blindness (revisited)
Intra-tower alignment is blind versus:
• translation
• shearing
• vertical scaling (horizontal is fixed by strip dimensions)
• rotation
• translation of the planes of one view vs. the other
• rotation of the planes of one view vs. the other
36
Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Translation
Intra-tower alignment:
absolute position of a
single tower is ambiguous
Inter-tower alignment:
tracks passing tower gaps
fix the relative positions
SOLVED
37
Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Rotation
Intra-tower alignment:
rotation of a single tower
with respect to some
coordinate system is
ambiguous
Inter-tower alignment:
tracks passing tower gaps
fix the rotation of one tower
vs. the others
SOLVED
38
Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Shearing
There is no way to correct for shearing from data!
Metrology measurements?
Average over all towers?
Do we care? 50μm vs 554mm for a perpendicular track = 0.1 mrad
40
Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss
Vertical Scaling
There is no way to correct the vertical scale from data!
Metrology measurements?
Average over all towers?
Do we care? 70μm vs 554mm for a 45° track = 0.1 mrad
41
Instrument Analysis Workshop 4, SLAC, 15 July 2005
Michael Kuss