Digitization and hit reconstruction control

  In a similar manner the control cards DIGI, RHIT and RECO are used to control the digitizations, hit reconstruction and event reconstruction. The control cards DIGI and RHIT are used to control the hit reconstruction. Hit reconstruction can be performed directly from HITS structure (HITS RHIT) using Gaussian smearing or from the DIGI structure (HITS DIGI RHIT).

In the following example the smearing method is selected by switching off the digitization:

DIGI 'TRAK' 0             (go from HITS to RHIT by smearing method)    
RHIT 'TRAK' 1

So switching DIGI explicitly off and asking RHIT will imply the smearing method. If the events are input and they contain already the DIGI structure one has to use the GET card in order to copy the DIGI structure from the file to memory. The data cards

GET 'DIGI'    
RHIT 'TRAK' 1             (RHIT is made with no stereo matching)

imply that the RHIT structure should be made from the DIGI structure.

For stereo layers the default is to store the hits from the two sides as separate hits. Optionally one can perform the stereo matching on RHIT level by combining the information of the two sides with possible ambiguities. This option is chosen by the card as:

RHIT 'TRAK' 2             (RHIT is made with stereo matching)