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Pad-row Configurations

The following scenarios concerning the available TPC pad-rows were considered:

  1. Full TPC
  2. Pad-rows 21-45
  3. Pad-rows 30-45
  4. Even Pad-rows
  5. Third Pad-rows: Pad-rows multiple of 3.

The fast pattern recognition has the possibility of considering tracks as coming from the primary vertex in the plane perpendicular to the beam. This option will be referred to as vertex constraint. In fact the primary vertex position is not calculated since it needs tracking information not available at that stage. The program considers all tracks being originated at a fixed point (0,0). This approximation should be good enough in realistic conditions since the transverse beam dispersion is less than a milimiter. The vertex constraint makes the pattern recognition algorithms simpler. However this option has a serious drawback. This is the lost of all information concerning tracks coming from secondary vertices, since they are forced to pass through the primary vertex.

Pablo Pedro Yepes
Thu Apr 27 10:00:13 EDT 1995