This directory contains all the parameters needed for tracker data reduction. 

During the compilation of "level2.exe" program, these auxiliary files are moved
in the directory "bin-aux", which is created together with the executable. 
The "official" files (that is those that are copied in "bin-aux") for 2005 data 
are the following:

align_param/parameters_l*s*.dat 
align_param/mech_pos.dat 

eta_param/eta*_binning.dat 
eta_param/eta*_bin*_l*.dat 

charge_param/charge-l*.dat 

field_meas/*.rz 

(NB! The program "level2-2003.exe" is associated with different parameters sets, 
labelled with "2003")

All the other files and directory are different versions of the same parameters,
that are kept in some case just for historical reasons.
It follows a short description of the data.  

==============================================================================
- align_param-COLONNE  
Alignment parameters for the coloumns, from CERN beam test 2003

- align_param-2003
Same alignment parameters as align_param-COLONNE, associated with the new
mechanical positions

- align_param-OTTICI   
Alignment parameters for the whole tracker, using the optical measurements to 
fix the relative positions  of sensors in the two reference plane. 
The procedure was applied to test 2003 data, and compared with the previous.
The result seems not good. It may be due to a variation of the sensor position
after inserting the planes in the tower.

- align_param-MUONI    
First set of alignment parameters obtained with muon, from Rome 2005 runs. 
The idea is to correct the parameters for the columns, from test 2003, by
varying the relative positions of the column (by means of tarcks that cross 
the columns).
The result is not satisfactory. 
The reason is that meanwhile we realized that from 2003 to 2005 the planes
moved... becouse of the vibration test.

- align_param-SHIFTS-then-MUONI  
We then tried to apply the procedure above, after having corrected the relative
positions of the planes for x and y translations, evaluated from the residual
distributions.

- align_param-COLONNE-shift2
Since also the procedure above does not convince, we first corrected the 
parameters from the shifts only (better evaluated) and see what happens.
However, even after the correction, the residual distributions are not centered.

- align_param-COLONNE-shift3
The correction above was iterated.

- align_param-COLONNE-RIALIGN
The column have been realigned, by using the measured muon momentum corrected 
for the estimated deflection offset.

- align_param-COLONNE-RIALIGN2
The column have been realigned, by using the measured muon momentum corrected 
for the estimated deflection offset.
The alignment was repeated to get correct error estimates for all the columns.
Now residuals and charge ratio seems to be ok and the offset in eta is removed.

- align_param-COSMIC
Alignment of the whole spectrometer using cosmic muons, strarting from the
align_param-COLONNE-RIALIGN2 for the single columns
                                                                                                                         
==============================================================================

- mech_pos.dat-old
- mech_pos.dat-new
Mechanical position of the sensors. In the old version the tickness of the
carbon stiffners was wrong. 
NB!! To each set of allignment parameters must be associated the proper  
mechanical positions (old-old new-new ... but for some exceptions)

==============================================================================

- charge_param-2003
- eta_param-2003
Charge correlation parameters and eta2 correction functions, evaluated from test
2003 data. In this set of parameters not all the angular bins are populated.

==============================================================================

- data-card.dat
This file is needed for charge correlation calibration.