Feb 8, 2018 Calorimeter

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Video Conferencing Information

Meeting Time: 11:00 a.m.

  1. To join via a Web Browser, go to the page [1] https://bluejeans.com/907185247.
  2. To join via Polycom room system go to the IP Address: (bjn.vc) and enter the meeting ID: 907185247.
  3. To join via phone, use one of the following numbers and the Conference ID: 907185247.
    • US or Canada: +1 408 740 7256 or
    • US or Canada: +1 888 240 2560
  4. Upon connection all microphones are automatically muted. To unmute your mike on a Polycom or equivalent unit, enter *4. Unmuting on a computer is trivial as there is a microphone button than can be clicked.
  5. More information on connecting to bluejeans is available.

Participant Direct Lines

  • JLab Phone in CC L207 is 757-269-7084 (usual room)
  • JLab Phone: in CC F326 is 757-269-6460
  • Phone in the Regina Video-conference Suite is 306-585-4204
  • Athens Phone: in Christina's office is 011-30-210-727-6947

Action Items

  1. Check in the code, including scripts, that is used for recent calibrations into git (BCAL: Mark)
  2. Add monitoring plots for charged particle clusterizer [Will to suggest plots and collaborate with Mark] Now working
  3. Checks of MC calibrations for BCAL. Timing (Sean and Mark), non-linearities (Will) Reported at last meeting.

Complete after new launch

  1. Report back on study of eta with in FCAL [Mark]
  2. From Mike's work: -cos(phi) type dependence in the data and a phi dependence at the downstream end of the bcal


  1. FCAL HDFCAL log book
  2. BCAL HDBCAL log book

Tentative Agenda

  1. Announcements
  2. Action Items
  3. FCAL Update
    1. Run related
    2. Other updates
  4. BCAL update
    1. Run related
    2. Other updates
  5. Calibrations
  6. Reconstruction and Simulation
  7. NIM articles
  8. Any other business


Attending: Elton, Simon, Ahmed, Mark, Justin (JLab); Matt (IU); Zisis, Andrei, Tegan (UofR)

  1. Announcements
  2. Action Items
    • See updates above
  3. FCAL Update
    1. Run related
      • Colin is taking advantage of all hall accesses to fix hardware problems and addressing most.
    2. Other updates
  4. BCAL update
    1. Run related
      • Mark: Tools to do calibrations are in place and being exercised. These are to find and adjust the 32 ns offsets in the TDC, 5 ns crate offsets and then individual offsets in the FADCs. Constants have been determined for all runs to date. However, running over 100k events for checks indicates some issues (~2 ns shifts) remain and are being investigated.
      • Once the time offsets are checked and understood, Mark will do the attenuation length and the gain ratio calibrations. Tegan can then work on the gain calibrations
      • Tegan: ran a few passes to check data/procedures but has some questions for Will, who is on shift.
      • LEDs (Ahmed): Checked the skimmed files for 80 runs. Some issues have been identified. Some runs do not have histograms. Some periods only sector 2 is firing (perhaps the pulser was stuck?). Planning to produce stability plots soon and make a log entry, possibly by the end of the day.
    2. Other updates
  5. Calibrations
  6. Reconstruction and Simulation
    1. Tracking matching to FCAL (Simon)
      • In the linked slides, Simon describes the differences between the old and new tracking procedures.
      • The new system takes less memory and runs faster
      • New system uses tighter matching cuts than old
      • New system finds about 0.67 omegas/1k triggers compared to 0.57 omegas/1k triggers for old.
      • Matt: Tighter cuts are probably ok, since one of the main uses of the tracking is to veto hadronic interactions to select neutral showers.
      • Simon: Could be room for further tuning of cuts
      • Elton: There is a cut a low momenta that increases to large values to include hits far from center. Should probably limit the size of the cut.
      • Mark: May wish to select the data sample with a maximum angle (eliminate BCAL and interface)
      • Elton: May be useful to run same programs on a sample of electrons to verify matching for well-understood em showers.
      • Mark: May wish to use (r,phi) variables instead of (x,y)
    2. Separation of Photons and Neutrons in BCAL (Andrei)
      • Elton: The width of the pulses in the BCAL are typically 50-55 samples long and this may affect intepretation
      • Justin: Is the time rms just the rms of the raw pulses? Yes. How best to include into clusterizer? Looks very promising as a discriminator
      • Mark: Interested in working with sample of tagged neutrons in data to study separation. May work with Justin, who has a sample of neutrons from gp->pi+n reactions
      • Matt: Perhaps gp->rho+n reaction may be useful to select neutron sample in data.
      • Justin: Work to demonstrate that rms works in data as in simulation.
  7. NIM articles
    • Elton: NIM referees responded with comments to the paper and changes are needed. May comments were submitted, but the main concerns were a) large constant term in the resolution and b) details of implementation of the SiPMs. Working on both issues. Mark will provide some plots to respond to issue a). We will likely need to add at least one figure to the paper to clarify this issue. Aside from the run that is clear priority, issues should be able to be addressed in a couple of weeks.
  8. Any other business