Latest revision as of 09:58, 7 April 2025

Connection

Meeting time and location:

• 9:30 am EST (JLab time) remote only
• Connection information

Agenda

Detector checkout Sasha, Hakob, Vlad

• • Tuning timing delays for the ECAL alpha-source trigger [1]
  • Testing ECAL magnetic shielding
    • List of LED runs taken during the magnet ramp-up [2]
  • List of runs
  • LMS amplitudes

Restoring PS test setup [3]

• Fabricating prototype consisting of 5x5 PWO4 and 5x5 LG modules (PS test setup)
  • ECAL modules exist, have been testes using an LED
  • LG modules will be instrumented with the resistive dividers (borrowed from Hall D)
    • all dividers were testes
    • modified PMT coupling to the LG block, use G10 tensioning plate to push the PMT towards the module
    • testing LG PMTs (FEU-84)
  • The prototype will be places inside the CCAL box
    • modified the cooling plate to accommodate all modules

Monitoring

Calibrations

Minutes

Attendees: Yuyao, Sasha, Hakob, Vlad, Igal, Bill, Zisis, Mac, Drew, S.T.

• Final detector checkout completed
  • Timing delays of reference PMTs relative to LEDs set
  • No new issues with dividers found
• While solenoid was ramping up, studied how well ECAL magnetic shielding was working by looking at changes in amplitude using LMS data
  • Found maximum relative difference between full field at 1350 amp and low field (not quite at 0 amps) ~3%
    • Deviations not symmetric about the beam pipe -- most differences seen in south top quadrant of ECAL
      • GEMTRD prototype is below south bottom quadrant
      • Impact of DIRC boxes?
  • Looked at deviations as a function of field for several channels
• Setup of 5x5 PWO + 5x5 LG prototype to be installed on PS arm in hall continues
  • Need table rated for weight of COMCAL box plus crystals and blocks
  • Need 2 more flash-ADCs
  • Base of COMCAL box extended to accommodate all LG blocks
  • Using resistive bases for LG borrowed from Hall A
    • Good signal quality but large spread in amplitudes
    • Dividers use connector that needs to be converted to SHV, patch panel needed
  • Hakob checkout out all LG modules using dark box
  • Tensioning plates to push LG PMTs toward cookies being added
  • Added block to align lead tungstate crystals with LG blocks
  • Ready to start assembly
  • PS arm occupied for first ~1.5 months
• S.T. on FCAL/ECAL shower reorganization