JEF meeting, May 2, 2025
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Meeting time and location:
- 9:30 am EST (JLab time) remote only
- Connection information
Agenda
- ECAL maintenance and performance during the run
- Issues with the HV [1] [2] [3]
- Status of the calorimeter after the maintenance day [4]
- Integrating ECAL into the trigger [5]
- Run conditions and trigger rates [6]
- HV module disconnected from the EPICS control
- Bad flash ADC for reference PMTs
- Low-level histograms [7]
- Adjusting high voltages
- iteration 5 (based on the run period 10, iteration 0) [8]
- Recent ECAL occupancy, production at 300 nA with 4x10^-4 X0 Al radiator [9]. Suspicious modules after the accelerator maintenance day
- Questions to address:
- Rates in the detector
- Gain stability
- Calibrations
- Monitoring
- Discussion of analysis topics and task division
- Priority decay channels (Liping)
Minutes
Attendees: Hakob, Igal, Olga, Liping, Phil, Sasha, Bill, Drew, Vlad, Yuyao, Zisis, S.T.
- ECAL detector has been commissioned and incorporated into the trigger
- 5 iterations for hardware HV settings
- Gains ~1 with 2% width
- Issues with HV: 2 modules dropped HV, failed twice in a day
- External power cycling of crates now available
- 2 connector problems identified, both fixed but one does not have a final fix (needs connector replacement)
- Need to study performance at high rate and monitor gain stability over time
- Look at LMS data for stability
- Temperature dependence: saw shift in π0 mass position correlated with temperature
- 4 inner rings excluded from trigger
- Need to exclude more rings to go to higher rates
- Igal working to add ECAL to π0 skim
- Discussion of JEF physics priorities
- π0γγ Standard Model measurement then look for Beyond Standard Mode physics
- π+π-π0 Dalitz analysis then mirror asymmetry + π-π+ resonance search (BSM)
- e+e-γ dark photon search
- 2γ normalization reaction + Primakoff
- Would like to have preliminary result in time to submit proposal to next PAC for more time
- Need to understand backgrounds
- Will not have final calibrations in place
- Calibrations are ongoing procedure as data is accumulated -- use student help for initial calibrations?
- Need good CDC calibrations for recoil proton, can consider not requiring reconstruction of proton: missing mass technique
- For Primakoff, special Compton runs? How much data do we need? or triplet production?
- Small scale prototype to be installed in PS arm
- Can move to hall
- Anticipate data taking in June
- Student identified
