4.4 User detector simulation.

In the detector simulation, You might want to supply the routines ZDEFFI, ZDIDEN and, maybe, ZDCALO:

• ZDEFFI(SEEN,PP,LAYLIS) is used to simulate detection inefficiencies. By default, all tracks in the acceptance are also seen. The arguments are

     INPUT :
       PP   : 4-momentum of track
       LAYLIS : List of detector layers hit by particle :
                LAYLIS(1,i) = number of the i:th hit layer.
                              LAYLIS(2,i) tells if it is a  plane
                              or a cylinder, if it measures or not,
                              and if it is the reference layer.
                LAYLIS(2,i) = 0  : mathematical layer : no material,
                                   no measurement. Ignored in all
                                   calculations
                              1  : seen by a cylinder
                              2  : seen by a plane
                              -1 : particle went through a cylinder, but
                                   was not seen by the detector.
                              -2 : particle went through a plane, but
                                   was not seen by the detector.
                              10 : the layer is a reference cylinder
                              20 : the layer is a reference plane
                LAYLIS(3,i) = No. of radiation lengths in layer.
                LAYLIS(1,i) = -1 -> end of list.
  
     OUTPUT:
       SEEN : .TRUE. if track seen by the detector, .FALSE. if not.
  

  ZDEFFI can be used to completely remove a track, by setting SEEN to false, or to remove hits in some detectors, by setting LAYLIS(2,i) negative for that layer. See the out-commented examples in the routine.

• ZDIDEN(CDSEEN,PP,CODE,LAYLIS) is used to simulate particle identification.By default all charged particles are called pions. The arguments are :

     INPUT :
       PP   : 4-momentum of track
       CODE : true JETSET code of particle
       LAYLIS : List of detector layers hit by particle :
                LAYLIS(1,i) = number of the i:th hit layer.
                              LAYLIS(2,i) tells if it is a  plane
                              or a cylinder, if it measures or not,
                              and if it is the reference layer.
                LAYLIS(2,i) = 0  : mathematical layer : no material,
                                   no measurement. Ignored in all
                                   calculations
                              1  : seen by a cylinder
                              2  : seen by a plane
                              -1 : particle went through a cylinder, but
                                   was not seen by the detector.
                              -2 : particle went through a plane, but
                                   was not seen by the detector.
                              10 : the layer is a reference cylinder
                              20 : the layer is a reference plane
                LAYLIS(3,i) = No. of radiation lengths in layer.
                LAYLIS(1,i) = -1 -> end of list.
  
     OUTPUT:
       CDSEEN : Seen JETSET code of particle
  

Look at the out-commented examples for clues how to write the routines.

(for ZDCALO refer to chapter 5.3 ).