1. Description of the misaligned geometry:
x,y translation
z translation
rotation

2. Misaligned geometry concerning the barrel
<0 part of the barrel
translation dx=-2 et dy=-1  modulation on  with peaks on and 0.46
translation on z of 4 mm, this has been corrected using depth=middle of sampling we expect a 2.5 mm effect on z
>0 part of the barrel
translation dx=2 et dy=-3  modulation on  with peaks on and 2.16
same translation on z
rotation  dependence on  depending itself on 

3. 1) z translation
4 mm

4. On veut: ’   pour que r/tan-4=r/tan’
4 mm
r/tan’
On veut: ’   pour que r/tan-4=r/tan’
As we can see, the correction depends on the value of r that is used

5. <Zvertex-Ztrue>+2 mm
middle
strips
centre of the layer:
was used to make these corrections
barycentre:
should have been used (geant)
Example:
for =1 we have rbar=1560 and rctr=1520 for the strips
and rbar=1705 and rctr=1760 for the middle
that if we apply in the equation: r/tan-4=r/tan’ we get:
strips= instead of = for the strips and
middle= instead of = for the middle
and because Zvertex= Zvertex(pointing)= Zvertex(strips,middle) we calculate that we can have an effect of:
<Zvertex-Ztrue>+2 mm

6. For the pointing we use the shower depth (GEANT) and not the centre of the layer
This dependence on Zvertex indicates that the used r is not totally correct
z=zpointing-ztrue (mm)
Ztrue (mm)
We use instead a depth re-calculated by Guillaume and there is almost no such dependence
z (mm)
Ztrue (mm)

7. RMS=21.75 mm
(and <z>~4 mm - for the negative AND the positive part)
z (mm)
But the RMS is slightly higher with this depth. Why?
RMS=22.8 mm
z (mm)

8. If we don’t apply corrections, we see the z=-4 mm effect:

9. After the corrections: (for the negative part of the calorimeter)
we see the
~ 2 mm effect

10. 2) x,y translation

11. ideal description of the detector
misaligned detector x
z=-r/tan
and as we can see: r=r() y

12. the position we think that the calorimeter is when we use the ideal geometry for reconstruction
real position of the calorimeter z

13. z in function of  for the <0 part of the calorimeter after correction
Z (mm)
expected peak at rad
we can also see the ~2 mm effect
 (rad)
expected peak at 0.46 rad

14. z in function of  for the <0 part of the calorimeter without corrections
Z (mm)
we can see
that z=-4 mm
 (rad)
There are difference between these two dependences (for instance, why the dependence is of an opposite sign)

15. z in function of  for the >0 part of the calorimeter
Z (mm)
Effect not clear because of the additional rotation
 (rad)

16. A first look at the end-caps
positive end-cap
not a clear problem for the moment, probably not misplaced? or not much…
negative end-cap
the distribution is clearly not centred at 0

17. To do:
Look at each layer separately
Look at end-caps

18. backup

19. We look at z for each layer (barrel):
strips:
RMS =
mean ~ +25
middle:
RMS = 3.753
mean ~ -30

20. r for each layer for the positive part (end-cap):
strips:
RMS = mm
middle:
RMS = mm

21. r for each layer for the negative part (end-cap):
strips:
RMS = mm
middle:
RMS = mm

24. z (mm)
:for the “official” depths
Ztrue (mm)
:for the Guillaume’s depths
z (mm)
Ztrue (mm)