Standard production of alignment objects

While the use of the constructors of the AliAlignObj derived classes has been explained in the pages describing the functionality of the alignment framework, we give here a brief description of the macros producing alignment objects for each detector. These macros include

  • the detector macros $ALICE_ROOT/DET/MakeDETMisAlignment and
  • the steering macros $ALICE_ROOT/macros/MakeAllDETsMisAlignment

where type is Zero, Res or Full
The detector macros define the expected deviation of the position of alignable volumes w.r.t. their ideal position (full misalignment) and the expected resolution in the knowledge of these position after survey and alignment procedures will be run (residual misalignment).

The user can run either one of the steering macros or directly the macro for his/her detector only.
The steering macros call the macros of all detectors for the corresponding type; they take care of setting the needed environment variables and running the needed additional macros, if needed. They are launched in the following way:

.x $ALICE_ROOT/macros/MakeAllDETsMisAlignment("cdburi");


.x $ALICE_ROOT/macros/MakeAllDETsMisAlignment("cdburi",kTRUE);

the first argument specifying the uri for the CDB storage where one wants to create the alignment objects (as the STORAGE variable explained below), the second argument, which defaults to kFALSE, corresponding to the STORAGE environment variable for partial geometry (also explained in more detail below). In case the user is running his/her detector macro directly, it will needed to consider those preliminary settings by hand, as explained below.

The environment variables used by the macros are three; if not explicitly set to kTRUE they are considered false.

  1. TOCDB is to be set to kTRUE when the user wants to produce the alignment objects in a CDB storage; in this case the user will have to set also the next environment variable STORAGE variable to the uri of the storage. For example, supposing you are in a bash environment:
    export TOCDB=kTRUE
  2. STORAGE corresponds to the uri of the storage
    export STORAGE="local://$HOME/MyCDB"
  3. PARTGEOM is to be set to kTRUE when the user wants to produce objects for partial geometry (some TOF TRD sectors are switched off):
    export PARTGEOM=kTRUE

    Note that in this case the config-file passed to the macros updating the geometry in the given CDB storage (UpdateCDBIdealGeom.C) must be consistent. As an example the Config.C produces a full geometry, while the Config_PDC06.C produces a partial geometry.

If the objects are produced on file, the ideal geometry is loaded from $ALICE_ROOT/GRP/Geometry/Data; when saving to CDB instead the macro requires to load the ideal geometry from the same CDB storage. This implies that if you are running the detector macro directly and you are saving the objects to a CDB storage, you have to first crate the ideal geometry file there:

aliroot $ALICE_ROOT/GRP/UpdateCDBIdealGeom("cdburi","configfile");

An additional care is to be taken when running directly the macros for TOF or TRD, since they are made dependent from the alignment objects for FRAME (the space-frame holding their super-modules). Thus in this case the user needs to run before:

aliroot $ALICE_ROOT/GRP/MakeSTRUCTMisAlignment.C