Aug 24, 2017 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]
  2. To join via Polycom room system go to the IP Address: ( and enter the meeting ID: 907185247.
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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, FCAL:Adesh)
  2. Add Fcal dead channels into the MC
  3. Find the geometry for the light tight cover to the FCAL (Elton)


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

Tentative Agenda

  1. Announcements
  2. Action Items
  3. Activities during the down
  4. FCAL Update
    • (From Richard) When/how the updated FCal geometry should be adopted for mainstream use? (Coordination between block size in geometry and gains from pi0 mass calibration)
  5. BCAL update
  6. Calibrations
  7. Reconstruction and Simulation
    1. 2017 mcsmear Workplan
  8. NIM articles
  9. Any other business


Attendees: Curtis, Will (CMU), Matt, Jon (IU), Christina (Athens), Andrei, Tegan, Ahmed, Zisis (Regina)

  1. Announcements:
    • Everyone saw Eugene's email yesterday on the anticipated running schedule (Dec 4-17, 2017, Jan 12 - Mar 22, 2018, Oct 3 - Dec 17, 2018). Curtis mentioned that the Dec and Jan-March periods will be lumped in a single block for shift allocation. The Dec period will probably be more heavily weighted to local people in case those shifts get cancelled. Curtis will put out a call for Run Coordinator volunteers soon.
  2. Action Items:
    • Item 3 from the above list (FCAL light-tight cover) has been resolved. The info passed from Matt to Elton to Richard.
  3. Activities during the down: nothing to report. Activities will commence approx a month before the run starts.
  4. FCAL Update
    • (From Richard) When/how the updated FCAL geometry should be adopted for mainstream use? (Coordination between block size in geometry and gains from pi0 mass calibration): Matt reported on how this should be best done. Block size changed to reflect 'as built' geometry, which means that it is now slightly larger. As a result, the cumulative error to the end of the detector is a few centimetres. The proposed plan is to change the geometry, adjust the calibration and make changes to the MC code all at once. As the next reconstruction launch will be after the DNP Meeting, this gives time to address the geometry. Matt will send a question to Sean on how tightly the calibration constants are coupled to the software version.
    • Matt showed a plot yesterday of the shower position for exclusive omega events. There is a hole near the beam hole. Structure is seen that may be due to calibration issues. Mike Staib provided a plot of the gain constants vs channel no that shows some unphysical values, larger by 6-10x of what is expected. Matt will overlay the gain constants to the shower position to check whether this affects the kinfit for the omega events. He will also look towards improving the timing resolution. Curtis mentioned that additional updates for the next reconstruction launch include dE/dx improvements in the CDC. The Offline Group is making plans for all these.
    • Photon shower project (summer student) is going well.
  5. BCAL update
    • Zisis reported that Justin, Elton, Andrei and he will chat later today on the topic of developing a neutron clusterizer. This starts with investigating the best observables to use.
    • Zisis updated the group on the BCAL LED work. Ahmed hopes to wrap up the comparison of May 2017 LED data to Mark's study from 2015, to investigate possible SiPM degradation. Early in the fall, the LED online and offline monitoring plans need to be finalized in preparation for the Dec run.
    • Tegan showed plots of the 2g mean, sigma, mean/sigma vs iteration number from exclusive pi0 events. Huge, divergent oscillations are present in the first 7 iterations, and after setting the gains so that the pi0 comes out at the correct mass, these died down. The old c-matrix code may not be working as well Will's new code. Tegan will try a few new things: start with the old calibration constants instead of starting with flat gains, use a damping factor, decrease the step size in the procedure.
  6. Calibrations: Sean's email (yesterday) showed that the FCAL timing is flat (no E dependence) and at around 400 ps. Matt verifies this; he has gotten it as low as 300 ps with tweaks. The BCAL looks crazy; folks need to digest this and address it.
  7. Reconstruction and Simulation
    1. 2017 mcsmear Workplan: Will reported that he is working on disentangling the position and energy smearing contributions as a function of pi0 energies, so as to see what is causing the simulation to fail in matching the data. He plans a log entry soon, possibly later today.
  8. NIM articles:
    • BCAL: Zisis reported that Elton and he will chat later in the day to go over the checklist for the BCAL NIM. The hope is to have it out to the collaboration for review soon.
    • FCAL: nothing to report.
  9. Any other business: none.