Continuing yesterday's measurements of the 8th vertical counters,
this time with the West side, we got the following results
(see yesterday's mail for details on measurements, notation and accuracy).
Cap-to-cap North-displacement South-displacement
-------------------------------------------------------
1W08 1195 12.5 8.5
1W09 1216
-------------------------------------------------------
2W08 1195 20.5 -0.5
2W09 1215
-------------------------------------------------------
3W08 1196 7.5 11.5
3W09 1215
-------------------------------------------------------
4W08 1195 20.5 0.5
4W09 1216
-------------------------------------------------------
5W08 1195 9.0 12.0
5W09 1216
-------------------------------------------------------
6W08 1195 10.0 11.0
6W09 1216
-------------------------------------------------------
CURRENT CALMOD GEOMETRY CONSTANTS
=================================
As far as CALMOD is concerned, the GEOMETRY section contains the
following information (last updated on RUN 6500). Please, keep in
mind that the position coordinate-system stored in CALMOD has the
following assignment
X-axis running from North -> South
Y-axis running from West -> East
Z-axis running from Bottom -> Top
with the origin somewhere at the bottom, North, West corner of MACRO.
This coordinate system is used to specify the positions of the *centers*
of all tanks.
On the other hand, the box coordinate-system is as follows
X-size: height of the box ( 19.0cm for horizontals, 43.0cm for verticals)
Y-size: width of the box ( ~73.0cm for " , 21.1cm for " )
Z-size: length of the box (1120.0cm for " , 1119.0cm for " )
- ALL vertical boxes (a total of 182) are listed as having length
(Z-size) 1119.0 cm
- Following are the differences in the position of the *center* of the tanks
along the X-axis according to CALMOD.
1W08 : 11.7cm South of 1W09 1E08 : 9.9cm South of 1E09
2W08 : 20.1cm South of 2W09 2E08 : 9.0cm South of 2E09
3W08 : 6.9cm South of 3W09 3E08 : 7.7cm South of 3E09
4W08 : 19.8cm South of 4W09 4E08 : 10.3cm South of 4E09
5W08 : 9.4cm South of 5W09 5E08 : 22.6cm South of 5E09
6W08 : 9.0cm South of 6W09 6E08 : 13.0cm South of 6E09
Note that these numbers are practically the same (within +-1cm) with the
measurements that we took for the *North* displacements of the x08 tanks from
the corresponding x09 boxes.
CORRECTIONS TO CALMOD (GEOMETRY SECTION)
========================================
Given our measurements, the corrections on CALMOD should be as follows:
(i) All vertical x08 lengths (Z-size) should be corrected to 1099cm
(20cm less than the rest)
(ii) A simple calculation tells us that all tank-center positions for
vertical x08 tanks should be 10cm less along the X-axis than the
value currently in CALMOD.
Note: For those interested in the active scintillator volume/mass, the
correction term is equal to -12*0.2*0.211*0.43 = -0.217752 m^3,
i.e. (with 0.87g/cm^3) = -0.189444 ton = -189.444 kg
I intend to do the above changes on the "work" DB and then run
the calibration software for 2-3 weeks' worth of LED/TDC and muon(TRK)
data. When the changes are in place, I will send an e-mail so that people
can run their analyses using the new constants and compare results.
Regards,
Ioannis Katsavounidis