March 15, 2017, Production & Analysis Working Group

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Meeting Time and Place

The meeting will be on Wednesday March 15, 2017 at 2:15 pm EDT. For those people at Jefferson Lab, the meeting will be in room F326-327.

Meeting Connections

  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: 115815824.
  3. To join via phone, use one of the following numbers and the Conference ID: 115815824.
    • US or Canada: +1 408 740 7256 or
    • US or Canada: +1 888 240 2560
  4. More information on connecting to bluejeans is available.

Reconstruction & Analysis Studies Status


  1. Announcements
  2. Data Production
  3. Analysis Focus
  4. This Week's Studies
  5. Any other studies
  6. Upcoming Study Schedule

This Week's Topics

  • Talks: Summary/overviews only. Detailed discussions should be held in the appropriate working groups.
  • Talks should be limited to 10 + 5 minutes.

Data Production

  1. Monitoring Update --- Thomas Britton
  2. Calibration Update --- Sean Dobbs
  3. Preparing for the first Spring 2017 production launch --- Sean Dobbs, Paul Mattione
  4. Processing Update --- Alex Austregesilo

Analysis Focus: Total Cross Sections

  1. J/Ψ, φ update Lubomir
  2. η, ρ, ω, φ First look at cross sections from Spring 2017 run--- Simon
  3. φ --- Thomas
  4. Any others?

Studies: Alignment & Track/Shower Efficiencies

(i.e. Is the reconstruction working?) Updates on experiment, simulation, and the comparison between the two.

  1. Drift chamber alignment --- Mike Staib
  2. Tracking Efficiencies (Link) --- Paul Mattione
  3. BCAL Shower Efficiencies (Link) --- Elton Smith
  4. FCAL Shower Efficiencies --- Jon Zarling

Upcoming Study Schedule

  • Updates on experiment, simulation, and the comparison between the two.
  • Summary/overviews only. Detailed discussions should be held in the appropriate working groups.
  • All talks should be limited to 10 + 5 minutes.
  • Next Week: Other (Any of below if update ready)
  1. Track / Hit Matching: BCAL, FCAL, TOF, SC
  2. Efficiencies: TOF, SC
  3. Means & Resolutions (time, energy, dE/dx): Tracking, BCAL, FCAL, SC, TOF
  4. Uncertainties: PID (BCAL, FCAL, TOF), Kinfit (BCAL, FCAL, tracking)
  5. Channel/Analysis Studies: Branching ratios, cross sections, SDMEs, beam asymmetries
  6. Other reconstruction/analysis issues
  • Week after next: Beamline & Triggering
  1. Flux --- Justin
  2. Beam energy --- Beamline Group
  3. Polarization (TPOL & lineshape) --- Beamline Group
  4. Trigger emulation --- Alex Somov
  5. Triggering efficiency --- Alex Somov
  • The following week: Hit Efficiencies (i.e. Is the detector working?)
  1. CDC Hit Efficiencies --- Naomi Jarvis
  2. FDC Hit Efficiencies --- Alex Austregesilo
  3. BCAL Hit Efficiencies --- Elton Smith
  4. FCAL Hit Efficiencies --- Jon Zarling



  • The meeting time from now on is moving to 2 PM.

Data Production

  1. Sean gave a report on the status of calibrations from the run that just ended. Timing calibrations in process, and an "acceptable" version should be ready by Monday. He will send out an annoucement email. Expect unexplained changes and inconsistent results until then. 2/3 of the data is skimmed, and the jobs for the last 1/3 have been launched. Calibration skims and skims of all non-physics trigger types are being created. Higher-level calibrations are underway. Please see his slides and checklist for more details. Several tasks could use more hands, and Sean will organize this.
  2. Paul talked about preparations for the first production launch. This included:
    • We need to determine the different parts of the runs with consistent conditions.
    • A first pass at what the "good production" runs are has been done. Sean pointed out that more culling will come out of calibration activities, but we should also consider how to categorize runs used for special conditions, e.g. the "low-rate runs" used for efficiency studies.
    • Weekly monitoring launches are planned.
    • Rough estimates for beginning of production and the length that this may take are starting at the beginning of May and taking 6 weeks. We agreed in principle to separate production for the low and high rate running. Sean will set milestones and circulate them.
    • Matt Shepherd suggested creating "reduced" REST skims that are more likely to contain "interesting" events. Various potential definitions were discussed.

Analysis Focus: Total Cross Sections

  1. Lubomir presented some slides indicating that a fiducial cut rejecting small angle tracks substantially reduced the background in the J/psi region.
    • It appears as though this background is due to potentially in-time electromagnetic background events which are reconstructed in the FDC. Several suggestions were made, like looking at tracking chi^2 and the timing of matched hits in the start counter and TOF.
  2. Simon showed some preliminary rho and omega cross sections and their ratios from the Spring 2017 data. He used the REST files form the latest monitoring launch. The results are all over the place, but the calibrations are very preliminary, so the results should not be taken too seriously.
    • He plans to check his flux calculation with Justin's
  3. Thomas is looking at the phi cross section, his DSelector code is working now and producing results. He has also updated his MC wrappers and is trying to use hdgeant4 to extract these cross sections.

Studies: Alignment & Track/Shower Efficiencies

  1. Drift chamber alignment --- Mike Staib
    • Current status as discussed at last tracking meeting: wasn't able to get satisfactory alignment in the FDC when fixing the alignment of the wire layers. Now making some other modifications, including trying to fix the wire and strip pitches. The calculation is ongoing and keeping the CMU farm very busy.
  2. Tracking Efficiencies (Link) --- Paul Mattione
    • Preliminary pion tracking efficiencies using gamma p -> pi+ pi- pi0 + p, with one pion missing, and selecting events in the omega peak. This gives a very clean sample with loose cuts that, with some caveats, yields effieicneis of 70-80% in the CDC, 65-80% in the FDC, and 55-65% in the transition region.
    • Paul is also looking at other topologies to reach larger angles, and is trying to clean up distributions to look at the proton efficiency.
    • Eugene asked for some 1D plots of efficiency versus theta for various strips in momentum.
    • Matt suggested trying an alternate method of fitting the omega peak with and without the reconstructed track to extract the efficiency.
  3. BCAL Shower Efficiencies (Link) --- Elton Smith
    • Elton took an initial look of the layer-by-layer efficiency of shower reconstruction. There are some features not entirely understood, but the results are broadly reasonable and in agreement with what was seen in previous runs.
    • The goal is to match these efficiencies from data in simulation, and this work is on-going.
  4. FCAL Shower Efficiencies --- Jon Zarling
    • Jon is doing something similar to what Paul is doing with omega decays, except with the photons from the pi0 decay. He is still working on finalizing his results.