Difference between revisions of "December 17, 2014 Calibration"

Revision as of 17:40, 18 December 2014

GlueX Calibration Meeting
Wednesday, December 17, 2014
11:00 am, EDT
JLab: CEBAF Center, F326

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Agenda

1. Announcements
2. Status Update
3. Calibration status/updates
   1. Calorimetry
   2. Tracking
   3. Timing
      1. TOF Matching (Paul)
         

         TOF Matching (Paul)
4. Calibration Skims
5. Simulations
6. Data Monitoring
   1. Quick summary by Kei
   2. Commissioning Software
   3. Run Browser, Plot Browser, and Time Series webpages
7. Peak hunting / higher-level analyses
8. AOB

Minutes

Attendees: Mark D., Mark I., Dave M., Paul M., Will M., Curtis M., Kei M., Zisis P., Eric P., Andrei S., Matt S., Elton S., ST, Justin S., Beni Z.

• Status of ccdb:
  • Entries for rollover/tframe for TDC has been added to ccdb. The relevant parameters will also be in the data stream (at the beginning of the run? how do we handle the multiple files per run?)
  • Placeholder for v_eff for TOF scintillators has been added.
• BCAL
  • SiPM gains based on Andrei's initial analysis
    • No measured constants for ~50% of the channels in the BCAL due to too low gain, threshold effects -- put in rought guess
    • Will M. has reconstructed π0 peak at ~160 MeV
    • Mark D. added scale factors to move peak down to nominal mass.
  • Next step is to add attenuation lengths to the database (the table already exists)
    • Measurements from beam data give values ~520 cm, whereas earlier studies indicated values closer to 380 cm using phototube readout
    • Reflections have been seen on the signals.
  • Mark D. has seen some strange 2-peak behavior in some TDC channels in the BCAL -- these double peaks do not necessarily show up in the same TDC from one run to the next.
  • Elton has been working on a draft document describing the BCAL calibration constants: [2]
• FCAL
  • Matt S. is working on calibration using π0s; he's working on filtering out the noise by looking at 3 photon events with the aim to cut on an ω(782) peak