Tracker Software Review: Meeting 5¶

Wednesday, August 2, 1500 BST (0900 CDT)¶

Agenda¶

1. Introduction - K. Long
2. Actions from previous meetings
   1. AD: Compare data/MC efficiencies for 8681
   2. CR: Generate list of uncertainties and show what has been done so far (alignment, scattering, energy loss, field uniformity, etc).
   3. PK: Check dead channel & noise handling in MC.
   4. AD: pattern recognition/efficiency:
      1. Study “10%” of missing 5-point tracks; where in the p.r. does the missing point get rejected?
      2. Scan events in which 5-point tracks are rejected
      3. Remove requirement for one hit per station in data and study performance. Also, study multi-track MC
      4. Plot Chi2 distributions etc. on log scale (to emphasize tails)
      5. Optimize Chi2 cut for “MINUIT” variant
      6. Understand reasons for shape of hits-per-station histogram
      7. With KL, review s-z algorithm
   5. CH: track fit:
      1. Repeat study that was done to investigate whether field integration (e.g. using Runge Kutta) is required to compensate for magnetic field non-uniformity
      2. Make study of magnetic-field alignment with a view to establishing whether the present algorithm is sufficiently insensitive to reasonable assumptions of maximum field-misalignment
      3. Check Highland and Bethe against what is implemented in GEANT
         1. agree very well. simulated indiv structures, stations, good agreement
      4. Study p-value: split up contributions to p-value shape using MC and study shape in data, e.g. is there an error in the resolution per plane, handling of MCS, handing of energy loss, magnetic field, …

1. Report on actions: Pattern recognition: A. Dobbs
2. Report on actions: Track fit: C. Hunt
3. Next Steps for review
4. AoB

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Dial-in information¶

http://mice.iit.edu/phonebridge.html

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Attendance: KL, CR, PK, AD, CH, MU, DR¶

Notes:¶

Actions removed:

• Study “10%” of missing 5-point tracks; where in the p.r. does the missing point get rejected?
• Scan events in which 5-point tracks are rejected
• It may be necessary to revisit those again after fit optimizations are complete
• Remove requirement for one hit per station in data and study performance. Also, study multi-track MC
  • AD reported that relaxing the requirement had little effect on performance
  • Multi-track MC study is blocked since the MC does not simulate multiple triggers
• Plot Chi2 distributions etc. on log scale (to emphasize tails)
  • Done

Actions generated¶

1. Show distributions with sign per station per tracker
2. Show individual residual distributions to understand details - is the station 1 distribution a binning artifact or a constraint from the fit?
3. run analysis in MC and compare with data (8681)