RC meeting and Run Plan, Thursday, June 20th

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RC Meeting Information

Current RC: Silviu Covrig Dusa

RC Daily Meetings 1:00 PM , via Zoom and in person in the counting house meeting room (2nd floor).
No meetings planned during weekends and holidays, unless something important comes up.

Zoom info

Useful Links

Current Status

  • Production on LH2 at 22 µA

Run plan for Today

Production on LH2 at 22 µA

    • PS10=0, PS16=9
    • Config: "GEp-5-3Stream-NoHcalScalers"
    • Thresholds: ECAL = 70%, HCAL = 15% (depending on rate limitation)
    • Four hours runs
    • 5k replay every 15 minutes
    • Monitor Scaler Rates

Key Updates, Last 24 hours

  • Beam delivery has been excellent, average trip rate 7/h over the past 24h (as reported at the 8am MCC meeting)
  • MCC to decide if they will attempt to repair 2L18 today, before the weekend. The issue: there is no head room for the SL. If any other cavity goes down in SL there may be significant down time for repairs.
  • Riad announced that the current laser spot is getting to the tail end of its lifetime and a spot move is planned over the next 7-10 days. Should we consider a Moller measurement before the spot move?
  • HCAL threshold changed to 15%, per Mark's recommendation, running at this setting since about 11am 19-Jun-25.
  • Mark said that HCal calibrations over the weekend may afford us to try 35 µA on Mon!

Accumulated Charge

  • Total Accumulated Charge at Kin3 so far: 26.8 C (Goal: 100 C)
  • Total Accumulated Charge at Kin3 since June 18 Swing: 1.8 C

Current Issues

  • Plagued by DAQ crashes, during the last 24h we seem to have wasted 25% of beam time on DAQ crashes and recovery.
  • APV baseline sagging/broadening: HV test showed a significant reduction of the width at lower gain.
  • Online zero suppression performance (common-mode min values for online zero suppression were changed to zero for the first iteration of averaging until we are ready to deploy ROI readout and histogramming firmware).
  • HCAL calibration/trigger efficiency, almost complete, still waiting on replays to finish.

Shifts

  • Full up for until August at the moment :)

Subsystem Updates

  • ECal:
    • Got rid of hot channels, trig rate down by some 600 Hz, experts are pretty happy with the current calibrations.
  • HCal:
    • db change last night around 11pm changed the plots, which confused the shift workers. Tracking the issue took until 5-6am this morning, when Mark (saved the night) declared that the data looks fine.
  • GEMS:
    • Plots shown for 15 µA beam current show improvement at the lower end of the spectrum with the new APV baseline (change from 200-400 ADC ch to 700-800 ADC ch). Waiting for replays to assess the effect at 22 µA.
    • an MPD card seems to cause some issues. During the next maintenance day experts plan to assess it in the hall to see if it has to be changed.
  • CDET:
    • No updates, all good.
  • DAQ:
    • By far the largest contribution to experimental downtime, right now, is from daq. We seem to be wasting around a quarter of good beam time with daq issues! Alex estimates that it will take 2 weeks to get the firmware for the GEMs upgraded, which may improve things, but it is not certain.
    • It was suggested to implement a "reset" button in a gui separate from coda, which, when pressed, will reset "all" crates at the same time. Alex seems to believe that resetting everything at the same time would help with stability. As we are taking 4h runs, the "reset" button will be pressed twice a shift, at the end of each 4h run, and just before starting a new run. Once the hack is in place, detailed instructions will be written for shift takers on using it.
  • Analysis
    • No updates.

Beam Restoration Procedure

Beam requirements

  • start off at 5 pass beam
  • intrinsic beam size (at target): 150–600 µm
  • raster size: 2 mm X 2 mm
  • During kin#3 SBS magnet will be at 1762.23 Amp, the corrector magnets at -80A for all.
  • production run @ 22 µA for now
  • For later
    • production beam current : 50 µA (one can hope!)
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