January 18, 2012 Tracking CDC/FDC

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Meeting Time and Place

Wednesday January 18, 2012 at 11:00am At Jefferson Lab, the meeting will be held in F326

Connections

To connect from the outside, please use ESNET

  1. ) ESNET: 8542553
  2. )To connect by telephone, dial:
  • You can look up toll-free number at http://www.readytalk.com/intl
  • US and Canada: (866)740-1260 (toll free)
  • International: (303)248-0285 (toll call)
  • enter access code followed by the # sign: 3421244#

Hardware Agenda

  1. Announcements
  2. FDC Update logbook, [1], [2]
  3. CDC Update

Software Agenda

  1. Tracking Software: Paul
  2. Single proton tracking File:Singleproton.pdf
  3. Discussion of metrics to measure performance.
  4. Plan to address the memory bugs.

Hardware Minutes

Participants: Curtis, Naomi, Dave, Beni, Mark, Elton, Tim, Mark, Lubomir, Simon

FDC Update

  1. Pre-amp cards, cooling system and HV cables installed on the first package (see pictures attached: cooling brackets on the pre-amps visible, not the pre-amps itself).
  2. First package will be moved to JLab for testing with DAQ as soon as possible. Still need to make LV cables; will have 8 pre-amps per cable.
  3. Second package assembled and tested with a scope and source successfully. Will continue with pre-amp, cooling and HV installations after the first one is moved to JLab.
  4. Techs working now on the first cell of the third package. Tension problems (for a first time) on two field wires; had to replace them.

CDC Update

  1. 680 wires remain to be strung. We expect this to finish in early Feb.
  2. The techs are doing a lot of soldering practice.
  3. After finishing tension checks we plan to put ~500V on the wires (in air).
  4. The mapping plan is almost complete, we have identified which pins will go to which HVB. Most wires are 4" long (range is 3.75" to 5").
  5. Tim: aiming for cheeseplate delivery and surveying end Feb/March. Small parts (brackets) will be sent to CMU before then.

Software Minutes

  • Participants: Curtis Meyer, Paul Mattione, Naomi Jarvis, Beni Zihlmann, David Lawrence, Simon Taylor, Elton Smith, Mark Ito, Lubomir Pentchev, Matt Shepherd, Ryan Mitchell, Kei Moriya

Paul's Update

  • ALT2 Track Hit Selector fixed & now working, has much lower efficiency in FDC than ALT1 does.
  • Only noticeable improvement of ALT2 over ALT1 is the tracking chi-squares at the wire-based stage.
  • Fixes to ALT1 Track Hit Selector have significantly reduced the spike at confidence level < 1% in the time-based tracking near 20 degrees
  • Low momentum (< 200 MeV/c) pions are reconstructed with the incorrect charge ~40% of the time, roughly independent of angle. This occurs even at the track candidate stage.

Beni's Update

  • 300 MeV/c protons at 70 degrees get stopped in the CDC, have good track candidates, but are reconstructed at low efficiency due to poor track fitting

Metrics

  • Metrics: Pick very specific regions of the physical phase space in which to determine quantifiable tracking metrics, and compare over time to check improvement.
  • Physics quantities to study (feel free to add some):
    • For the following, test for: protons, pi+'s, pi-'s, k+'s in single track events, b1pi events, and cascade events using several hit selectors: ALT1, ALT2, & keeping the hits from the DTrackCandidate stage (don't redo hit selection).
      • Number of reconstructed tracks at each stage (e.g. useful for seeing if ~9 candidates for a single spiraling track, etc.)
      • track reconstruction efficiency at track candidate (helical), wire-based (kalman, no drift times), and time-based (kalman) stages
      • track charge reconstruction efficiency at track candidate (helical), wire-based (kalman, no drift times), and time-based (kalman) stages
      • at a given angle/momentum, the fraction of the tracks that have confidence level < 1% for wire-based and time-based track fitting
      • the % of the true # of track hits that are matched to a track at the track candidate (helical), wire-based (kalman, no drift times), and time-based (kalman) stages
      • the resolution of the measured track parameters (p, theta, phi) at the track candidate (helical), wire-based (kalman, no drift times), and time-based (kalman) stages
      • tracking pull distributions after time-based stage
      • PID: fraction of the time that the correct PID is assigned
  • Specific Regions of physical phase space:
    • Matrix:
      • theta: 2, 5, 15, 30, 60, 90, 120 degrees
      • pion momentum: = 0.15, 0.3, 0.8, 1.5 (30 degrees and less only), 2.5 (15 degrees and less only)
      • proton momentum: = 0.3, 0.4, 0.8, 1.5 (30 degrees and less only), 2.5 (15 degrees and less only)