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This performs the misalignment on an existing muon arm geometry based on the standard definition of the detector elements in $ALICE_ROOT/MUON/data
--> User has to specify the magnitude of the alignments, in the Cartesian co-ordiantes (which are used to apply translation misalignments) and in the spherical co-ordinates (which are used to apply angular displacements)
--> If the constructor is used with no arguments, user has to set misalignment ranges by hand using the methods : SetApplyMisAlig, SetMaxCartMisAlig, SetMaxAngMisAlig, SetXYAngMisAligFactor (last method takes account of the fact that the misalingment is greatest in the XY plane, since the detection elements are fixed to a support structure in this plane. Misalignments in the XZ and YZ plane will be very small compared to those in the XY plane, which are small already - of the order of microns)
Note : If the detection elements are allowed to be misaligned in all directions, this has consequences for the alignment algorithm (AliMUONAlignment), which needs to know the number of free parameters. Eric only allowed 3 : x,y,theta_xy, but in principle z and the other two angles are alignable as well.
1.9.8