Commands that control the tracking of particles

1. TRACKING or /EOS_GEANT/RUN/TRACKING TRACKING_OPT

   
   
   

   Control options for the GEANT tracking. Current items available under TRACKING are CONTROL, LIMIT, LIST, SET, and SPIRALS.

   Option CONTROL allows the user control of the step size in FSIM mode, for volumes other than the TPC. The current step size outside the TPC in this mode is hardwired to be 2.0 cm. The setting of this variable from the KUIP command line is a possible future option. The form of the command is

   TRACKING CONTROL ON (OFF)

   The default is ON.

   Option LIMIT limits tracking for those tracks passing out of the sides of the TPC. If this is turned ON, tracks above a certain minimum rigidity are stopped at the side walls. If this is turned OFF, particles will be tracked out to the CAVE boundary. The default is OFF. The command

   TRACKING LIMIT ON 0.5

   stops all particles below rigidity = 0.5 GeV/c at the side walls of the TPC.

   Option LIST allows updating of the tracking list. This list determines whether particles are to be tracked or not. The default (in the absence of a defined list) is for all particles to be tracked. The command

   TRACKING LIST IZ IA

   enters a particle of charge IZ and mass IA into the list. See Section 2.3.1 for the convention used for IZ and IA in the case of particles not composed of baryons.

   If the command TRACKING LIST is entered without other arguments, this has the effect of clearing the list. See option SET (described below) for the interpretation of the tracking list. The contents of the tracking list can be examined with the command INFO TRACKING (see Section 3.8).

   Option SET determines whether the definition of the list of particles is to be ``particles to be tracked'' or ``particles not to be tracked''. The command

   TRACKING SET INCLUDE

   defines the tracking list as ``particles to be tracked''. Alternatively the command

   TRACKING SET EXCLUDE

   defines the tracking list as ``particles not to be tracked''.

   Option SPIRALS determines the number of spirals a track may make within the active volume of the TPC. The command

   TRACKING SPIRALS 3

   allows a particle to complete three spirals in the TPC. The default number of spirals is 2.