January 18, 2012 Tracking CDC/FDC
From GlueXWiki
Contents
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
- ) ESNET: 8542553
- )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
Software Agenda
- Tracking Software: Paul
- Single proton tracking File:Singleproton.pdf
- Discussion of metrics to measure performance.
- Plan to address the memory bugs.
Hardware Minutes
Participants: Curtis, Naomi, Dave, Beni, Mark, Elton, Tim, Mark, Lubomir, Simon
FDC Update
- 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).
- 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.
- 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.
- 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
- 680 wires remain to be strung. We expect this to finish in early Feb.
- The techs are doing a lot of soldering practice.
- After finishing tension checks we plan to put ~500V on the wires (in air).
- 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").
- 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 in single track events and b1pi events using both the ALT1 & ALT2 Hit Selectors
- 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
- For the following, test for: protons, pi+'s, & pi-'s in single track events and b1pi events using both the ALT1 & ALT2 Hit Selectors
- Specific Regions of physical phase space:
- Matrix:
- theta: 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)
- Matrix: