July 16, 2014 Calibration

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GlueX Calibration Meeting
Wednesday, July 16, 2014
11:00 am, EDT
JLab: CEBAF Center, F326

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  1. Announcements
  2. Status Update
  3. Tracking
  4. Calorimetry
  5. Other systems
  6. Simulations and Calibrations


Attending: Sean, Amiran (NU); Simon, Mark I., Lubomir, Mike S., Beni, Eugene, Mark D., David L. (JLab); Curtis, Naomi (CMU)

  1. Status Update
    • Since one of the outcomes of the recent review was that we should make more detailed plans for the Fall commissioning, we spent some time discussing this.
    • Curtis walked us through the currently existing documentation. Most of the detail is for the requirements for the beam, though there is some discussion for the four largest detectors.
    • Some of the topics and general conclusions were:
      • Generally, the more detail the better. Given the uncertainty in when and how much beam will be available, this information would be useful in prioritizing activities in the fall and winter.
      • One possibility for adding detail would be a checklist of procedures or calibration values that need to be obtained.
      • Subdetectors should determine what types and how much data they need for calibrations. Again, this will help with scheduling.
      • The background rate in the detector will need to be determined somehow.
      • Monitoring software appropriate for each subdetector will be very useful for checking out the detector and getting initial calibrations.
      • Setting priorities for software development could be useful as well. At the very least, all the calibration procedures should be put in DANA plugins, stored in the subversion repository, and their use documented on the wiki.
  2. Tracking
    • Beni reported that there appeared to be several problems affecting a small number of CDC channels on many fADC readout boards. After much discussion, it was generally agreed that the problems should be understood, and hopefully fixed, but that this effort must be prioritized. For instance, getting sparsification working for the FDC is currently a higher priority.
    • Simon reported that he is looking at the CDC+FDC cosmic data that has been taken so far. He is seeing tracks from cosmic rays, but has to set high thresholds to deal with the noise, so the efficiency is lower than otherwise expected (i.e. not ~99%).
      • Mike S. thinks that there might be a problem with the CDC hits at some level and is working with David L. to understand this.
    • There was some earlier discussion of analyzing data taken with the magnetic field off to use it to calibration multiple subdetectors, where Simon decided to integrate his straight line track fitter into the standard tracking libraries.
  3. Calorimetry
    • Beni mentioned that progress is being made running the FDC/CDC + BCAL with a common DAQ system.
    • Eugene discussed some issues related to the gain balancing of the BCAL. An estimate of the amount of data needed would be useful, for cosmic rays and photon beam. He pointed out the importance of making sure the subdetectors are properly situated in the global coordinate frame, and suggested that the locations of the FCAL and its components should be measured and accurately put in the software.
    • Added in press: The FCAL group is currently working on software for gain balancing using LED data and putting the pi0 calibration code into a DANA plugin.
  4. Software
    • David L. reported that he's finished work on reading CAEN TDC data into DANA, and TOF hits have been seen with actual data.
    • Sean reported that the simulated HDDM -> EVIO conversion is currently broken, and he will work with David L. to fix this.