JEF meeting, January 24, 2025

Connection

Meeting time and location:

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

Agenda

Preparation of parts for ECAL -- Sasha

-The LMS light source should be ready in the beginning of next week (the flange was machined, the PCB box under preparation); will start testing.

-More powerful fans will be installed in the central region (Tim)

-Installation of the FCAL2 detector & integration to GlueX -- Sasha, All

• Implementing ECAL into the GlueX DAQ [1]

- Six VTPs have been installed, firmware loaded

- Testing GTP trigger using individual ECAL VXS crates [2]

• Commissioning the entire detector using the LMS (signal waveforms)

- Signal waveforms after resolving issues with the ECAL modules [3]

- Long-term stability check [4]

List of cosmic runs

• ECAL HV interlock check [5]
• Material in front of the ECAL, TOF absorber [6][7]
• Temperature scan in the ECAL divider region [8][9][10]

Lower detector high voltages [11]

Temperature of the NPS detector[12]

2 temperature sensors in the divider region connected, fan included into the detector interlock [13] -- Josh, Bobby

Meeting with Tim: More powerful fans will be installed in the inner region. Beam pipe can be cooled, need specs and technical details (decided to put on hold). Can operate the chillers at smaller temperatures.

• Preparing for the run -- Sasha

Page for shift Takers

ECAL in the Experimental Safety Assessment Document (ESAD)

EPAS for Maintenance of the Hall D ECAL (Jlab-PTW-5236)

• Safety briefings - Vlad, Sasha
• FCAL2 Engineering Meetings
• Detector installation page

Restoring PS test setup [14]

Working on the plan for testing calorimeter prototype

ECAL commissioning -- Sasha, All

Calibrations

-First look on cosmic data -- Zhikun[15][16]

-Adjusting HVs

-pi0 calib -- ig

-Compton scattering calib -- Drew

Analysis/Simulation

Minutes

Attendees: Liping, Sasha, Zisis, Bill, Axel, Drew, Phil, Vlad, Igor, Olga, Zhikun, S.T.

• LMS light source ready to go, still needs to be mounted to integrating sphere
• Parts for reference PMT are being 3D-printed
• 2 fans in center region of insert being replaced
• 6 VTPs for ECAL part of GlueX trigger have been installed
  • Firmware has been updated
  • LMS has been used to generate "physics" triggers
• Lingering issues (loose connections, cable issues,...) in ECAL have been resolved
• Cosmic runs ongoing
  • Some issues due to small data size coupled with DAQ crashes --> lost data
    • Will take relatively short runs to check stability periodically and avoid daq problems
  • ECAL stability over the scale of a week looks good
• Design of plastic aborber in front of TOF to be revisited
  • Support by hanging instead of thick insert through hole in TOF
• Still working on studying temperature variation when ECAL voltage turned on/off
  • Planning to lower chiller temperature
• Want to make sure that GEMTRD prototype does not obstruct the ECAL region -> survey data?
  • For final gain calibration of FCAL region want GEMTRD removed
• Zhikun has been checking ECAL gains using cosmic data
  • Using Landau convolved with Gaussian to fit peak positions
  • Already performed one revision of ECAL HV settings
  • Goal of putting peak position at 8 FADC channels may be revised to ~10 FADC channels
  • Comparing pulses in cosmic data to LMS data to check low amplitude LMS data
• Drew S. looked at feasibility of using Compton events for calibration
  • Reach of 2-arm Compton events with beam energy of 3 GeV is about 20 cm on the face of the ECAL
    • Detection effeciency ~15%
  • Single arm events might improve reach, but background level may be too high
  • Add additional tagger hodoscope counter to go to lower beam energy?
    • Also need to consider trigger
• Final gain calibration will be using π0 events