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Revision as of 18:33, 5 February 2021 by Pentchev (Talk | contribs) (Agenda)

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  1. Instructions for Bluejeans meeting connection
  2. Meeting ID: 290664653
  3. To join via a Web Browser, go to the page [1]

Thu 2/4/2021 2pm


  1. Tracking
  2. Detector related reports
  3. GEM-TRD
  4. Other - collaboration meeting


  1. Other: No tracking talk at the collaboration meeting. Some tracking related topics will be discussed in other talks.
  2. Tracking updates: Discussing the track-fitting quality, chi^2/ndf, vs theta for 2020, compared to the previous running periods. The deterioration for theta>10 deg should be studied with high rate reactions (Alex with rho) or just inclusively (Sean). Alex: many changes have been done in the tracking software for the 2020 production, need to evaluate their effect on the tracking quality. Discussions with Simon after the meeting: the new extrapolating algorithm doesn't affect the CDC region. The tracking problems could be related to the timing as the J/psi yields increased with loose timing cuts.
  3. Detector-related analysis
    • FA125
      • Cody and Naomi found mismatches between the firmware and the evio decoding software for fa125's itrigger and the trigger time in the event header. These are not used anywhere in the reconstruction software. After fixing this, the itrigger reported from each slot matches the event number, and the trigger times are half of the TI's reported time. This means that in future we can use the itrigger to check for misbundled event data.
      • During the meeting we thought there was a mistake in the filespec for both trigger number and trigger time, but in fact it was correct for the trigger time. After the meeting Naomi updated the fa125 format spec and fixed the readout software bugs.
      • Using the fixed software, the data from the rogue fadc in run 72932 seemed to be appearing one block late, which prompts more questions.
      • Cody and Sergey will check the online software to make sure that the SYNC resets are after the VME resets.
    • FDC
      • Alex worked on tuning the CCDB to account for inefficient wires during the spring 2017 run period. He reduced the efficiency of one quarter of package 1, cell 1 to 0.9 to model the effect observed in data. In addition, he switched off a several wires in package 4, cell 6 at the beginning of the run (30274-30412) and half of the cell 6 in package 3 towards the end of the run (30995-31006). The same procedure should be done for the 2018 run periods. Implementing and verifying additional inefficient strips is more complicated, but could also be a project for the future.
    • Kaon tracking efficiencies (Chandra)
  4. GEM-TRD: We finished with the CDC gas tests: no Oxygen at 100ppm level, so CDC is very gas tight. The Oxygen we see with the gas chromatograph most likely comes from the tubing at/around the bubblers. Will restore the gas in the CDC and do the same tests with the FDC. Kondo performed analysis of the resolution of the padGEM (1x1 cm^2 pads) for different pad patterns: found significant improvement (~300 microns) when you have 3x3 pads above threshold.