ACD Recon Upgrade

Major Changes

• Use Pattern Recognition in addition to GEANT model to determine which tiles and ribbons to associate with tracks
  • This allows us to handle near misses, which is needed to do efficiency studies
• Have information be associated with tracks, instead of having a single big set for the whole event
  • This makes using the event display much easier
  • This makes getting access to information in Recon root files easier
• Handle track errors correctly
  • This wasn't being done before
  • This looks nice in the event display
• Sort ACD - track associations by a combined signal size/ distance quality measure instead of using only distance
  • This gets rid of problems with shadowing, where one association with a small signal masked another nearby one with a larger signal
• Always calculate gaps to tiles
  • Before this was a hodge podge, we had to handle cases where the track hit ribbons, tiles and missed everything differently.

  Minor Changes

• Change the way the distance of closest approach is calculated when the POCA occurs exactly at the head of the track
  • This effects some events track which graze side tiles (and a very few which graze to tiles), but only when the distances of closest approach is quite large
• Use the hardware veto information instead of the energy information in counting number of tiles hit in the Merit Variables
  • This handles issues with the slower timing of the PHA electronics

Testing and Comparison

  Merit Variables that stayed exactly the same

Variables that changed slightly because we are using the hardware veto to count hits instead of the Energy corresponding to an expected veto

 Changes in the AcdTkr1ActiveDist set of variables