BARREL TRACKING

The example below describes a cylindrical detector at radius 6.3 cm, going from 0 to 10.65 in z (ie. from mirror symmetry, actually continuously from -10.65 to +10.65 cm), with a thickness of 0.5% of a radiation length. It measures R$\phi$ with a precision of 10 micron. Since this represents one layer of a silicon micro-vertex detector, the name VD-CLOSER has been chosen :

TYPE:  BARREL_TRACKING
      LAYER: VD-CLOSER
            GEOMETRY:  R=6.3, ZMIN=0.0 , ZMAX=10.65
            MATERIAL:    X0=.005,A=14
            MEASUREMENT: CODE=1, SIG_RPHI=0.001, SIG_Z=0.0

The next example is the same detector, with its support structure and read-out electronics added. This structure is a ring at each end from 10.65 to 14.65 cm (and -10.65 to -14.65 cm), with a thickness of 10% of a radiation length. It does not measure anything. Both these two elements have the name VD-CLOSER :

TYPE:  BARREL_TRACKING
      LAYER: VD-CLOSER
            GEOMETRY:  R=6.21, ZMIN=10.65, ZMAX=14.65
            MATERIAL:    X0=.100, A= 14
            MEASUREMENT: CODE=0
         LAYER:
            GEOMETRY:  R=6.3, ZMIN=0.0 , ZMAX=10.65
            MATERIAL:    X0=.005,A=14
            MEASUREMENT: CODE=1, SIG_RPHI=0.001

This is once again the same detector, but now also measuring z, with a perpendicular precision of 10 micron. The angular exponent is 2.6 :

TYPE:  BARREL_TRACKING
      LAYER: VD-CLOSER
            GEOMETRY:  R=6.21, ZMIN=10.65, ZMAX=14.65
            MATERIAL:    X0=.100, A= 14
            MEASUREMENT: CODE=0
         LAYER:
            GEOMETRY:  R=6.3, ZMIN=0.0 , ZMAX=10.65
            MATERIAL:    X0=.005, A= 14
            MEASUREMENT: CODE=1, SIG_RPHI=0.001, SIG_Z=0.001,
                          ANG_EXP=2.6

Here below is the same micro-vertex detector, but with some detail added. Instead of being a single continuous cylinder, it is two closely separated cylinders of plaquettes. The closer of the two measures R$\phi$ and z between 28 and 45 degrees, nothing between 45 and 58 degrees. The next layer is complementary : it measures between 13 and 30 degrees, nothing between 30 and 43. This pattern is repeated for each 30 degree sector of the full turn. In both layers, the non-measuring sector is empty. (Note that there is in fact a measuring sector that starts at -2 degrees and extends to 15 degrees. This is not entered as the first measuring sector, because it starts at 358 degrees, since angles should be measured in positive direction.) Hence, this describes a layer of a silicon microvertex detector made out of two cylinders of slightly over-lapping plaquettes: two 2 degrees over-lapping portions per 30 degrees.

TYPE:  BARREL_TRACKING
      LAYER: VD-CLOSER
            GEOMETRY:  R=6.21, ZMIN=10.65, ZMAX=14.65
            MATERIAL:  X0=.100, A= 14
            MEASUREMENT: CODE=0
         LAYER:
            GEOMETRY:  R=6.3, ZMIN=0.0 , ZMAX=10.65
            MATERIAL:    X0=.005, A= 14
            MEASUREMENT: CODE=1, SIG_RPHI=0.001, SIG_Z=0.001,
                          ANG_EXP=2.6,PHI1=28., PHI2=45., PHI3=58.,
                          EMPTY_TYPE=0
         LAYER:
            GEOMETRY:  R=6.3, ZMIN=0.0 , ZMAX=10.65
            MATERIAL:    X0=.005, A= 14
            MEASUREMENT: CODE=1, SIG_RPHI=0.001, SIG_Z=0.001,
                          ANG_EXP=2.6,PHI1=13., PHI2=30., PHI3=43.,
                          EMPTY_TYPE=0

This is a detector measuring angles and position, R$\phi$ with a precision of 60 micron and phi with a precision of 2 mRad :

TYPE:  BARREL_TRACKING
      LAYER : ID-JET
            GEOMETRY:  R=17.0 , ZMIN=0.0, ZMAX=40.0
            MEASUREMENT: CODE=2, SIG_RPHI=0.006, SIG_PHI=0.002

This is a detector measuring R$\phi$,z and $\phi$ :

TYPE:  BARREL_TRACKING
      LAYER : ID-TRIGGER
            GEOMETRY:  R=27.0 , ZMIN=0.0, ZMAX=60.0
            MEASUREMENT: CODE=2, SIG_RPHI=0.100, SIG_Z=0.1,
                          SIG_PHI=0.007

This is a possible description of a TPC, with 3 pad rows in radius, separated by 4.6 cm, and an inner wall of thickness 0.025 X$_0$ :

TYPE:  BARREL_TRACKING
      LAYER : TPC-IWALL
            GEOMETRY:  R=30.75 , ZMIN=0.0, ZMAX=134.0
            MATERIAL:    X0=0.025, A= 13
            MEASUREMENT: CODE=0

      LAYER : TPC
            GEOMETRY:  R=39.8, ZMIN=0.0 , ZMAX=134.
            MATERIAL:    X0=.0
            MEASUREMENT: CODE=1, SIG_RPHI=0.030, SIG_Z=0.1
         LAYER :
            GEOMETRY:  R=44.5, ZMIN=0.0 , ZMAX=134.
            MATERIAL:    X0=.0
            MEASUREMENT: CODE=1, SIG_RPHI=0.030, SIG_Z=0.1
         LAYER :
            GEOMETRY:  R=49.1, ZMIN=0.0 , ZMAX=134.
            MATERIAL:    X0=.0
            MEASUREMENT: CODE=1, SIG_RPHI=0.030, SIG_Z=0.1

A more compact way to describe the same dettector, using the REPEAT construct, would be

TYPE:  BARREL_TRACKING
      LAYER : TPC-IWALL
            GEOMETRY:  R=30.75 , ZMIN=0.0, ZMAX=134.0
            MATERIAL:    X0=0.025, A= 13
            MEASUREMENT: CODE=0

      LAYER : TPC
            REPEAT : TIMES=3 , DELTA_R = 5.0
               GEOMETRY:  R=39.8, ZMIN=0.0 , ZMAX=134.
               MATERIAL:    X0=.0
               MEASUREMENT: CODE=1, SIG_RPHI=0.030, SIG_Z=0.1
            ENDREPEAT: