RC meeting and Run Plan, Wednesday November 24th

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Daily_Meetings

RC Meeting Information

RC Daily Meetings are at 3:15pm, remote connection link: https://bluejeans.com/256205934

Current RC: Brad Sawatzky

Upcoming RC: Xinzhan Bai (Starting this afternoon)

Accelerator and Hall Status

  • Configuration change to SBS-11 completed during Tuesday DAY shift
    • LV cable got pulled out during changeover [1]; fixed, but something to watch/check after next config change
  • Accelerator worked on the pass change through Swing into Owl, got some beam into the Hall mid-Owl shift
    • Had difficulties completing the Raster and Beam position checkout. Possibly due to optics issues downstream of the raster in the A-line [2], [3]. Under investigation during day shift
    • Moller quads had an issue cycling -- now fixed [4]
  • DAQ latencies noted on the GEMs seem to be global and caused issues with data taking throughout the night
    • It is still unclear why the latency changed [5], [6], but they are being adjusted based on what we are seeing this morning. See more detailed notes in the DAQ sub-detector discussions
  • Had some trouble with BBhodo HVs [7]
    • Steve suggests a power cycle of the crate may help -- requires escorted access
  • Cryo flow to target was found to be constrained last night
    • This did not impact the program and was corrected this morning.
  • Ran into a few computer related issues during Tuesday swing, now corrected [8], [9]
  • 4th pass separator issue will be worked on today (Wednesday)
    • Original 4th Pass IOT ("IOT3") has been declared unrepairable (for now)
    • Plan is to move 2nd Pass IOT up to 4th (then move it back later in the program) [10]
    • This primarily impacts Hall C at this point, but there will be downtimes associated with reintegration and tuning once repairs are completed.

Run Plan for Wednesday--Thursday

This will be updated as we better understand what needs to be redone with corrected readout latencies.
We should be able to complete the 'Initial Beam steer-up', raster and beam position checkout this morning.


  • [Complete] Beam restoration to the Hall (MCC driven program to get beam to the dump)
    • BB Sieve is IN
    • Ensure target is OUT
    • GEM HVs OFF
    • SBS, BB Magnets OFF
    • All other systems should be ready to go

  • After initial steer-up into Hall is complete (call Don Jones if you have issues during Swing/Owl or David Flay during the Day Phone Numbers)
    • Verify beam profile with Harp scans
    • Determine raster size and position on target
      • When complete be sure to make a halog and update the whiteboard with the new raster and beam position numbers
  • Inform the RC when we get here. The plan will be to stop beam to Hall A and allow OPS to work on the 4th-pass line and RF separator system. We will stay in Beam Permit and retake the BBCal cosmics runs (below).
  • [Complete] Take BBCal cosmics data with magnets on to get HV settings established when above steering/raster checks are complete. (Call the RC)
    • Turn on BB (750A) and ask MCC to ramp SBS to 2100A
    • Ensure all detector HVs are ON, set BBCal threshold for Cosmics (~200 Hz), take 500k triggers
    • Keep beam out of the Hall until this is completed

  • Call MCC and ask that they complete their procedure to ramp SBS to production currents (2100A pos) and adjust correctors
    • This may require ramping BB to zero (ask them)
    • Verify beam position is still where you want it (centered on target)
  • Ask MCC will to complete Ion Chamber calibrations on LD2
    • 'Thin' target ion chamber calibration should be complete Wed OWL (covers carbon foils, dummy)
  • Prep for GEM/Optics checkout
    • Contact GEM expert (on whiteboard) to support the GEM checkout program
    • Contact Holly and Andrew [call numbers on whiteboard] as well, if this starts before midnight
    • Turn GEM HV back ON; Ensure other detectors are ready to go.
    • Initial threshold settings for BBCAL and HCAL
      • BBCAL threshold ~0.5 GeV (readback is: -100 mV)
      • HCAL threshold ~0.5 GeV (readback: -80 mV)
  • Optics Runs for SBS-11
    • Zero Field Alignment
    • SBS OFF, BB OFF, Sieve IN
    • single C foil target
    • BBCAL threshold 0.5 GeV (-100 mV); adjust threshold/beam to get a ~3 kHz of rate
    • I = 5 uA
    • 30 min of beam on target
    • Vertex and Angle Reconstruction 1/2
    • SBS ON (2100A pos.), BB ON (750A neg.), Sieve IN
    • 5-foil Optics target
    • BBCAL threshold 0.8 GeV (-160 mV)
    • I = 20 uA
    • 60 min of beam on target
    • Vertex and Angle Reconstruction 2/2
    • SBS ON (2100A pos.), BB ON (750A neg.), Sieve IN
    • 4-foil Optics target
    • BBCAL threshold 0.8 GeV (-160 mV)
    • I = 20 uA
    • 60 min of beam on target
  • Escorted Access to take Sieve OUT (needs trained personnel!)
    • Call RC ~1 hour before you will need to do this (Brad, Bill, _???_ are authorized to move sieve)
  • Low current GEM runs
    • SBS ON (2100A pos.), BB ON (750A neg.)
    • BBCAL threshold set to establish sufficient rate for a GEM efficiency HV scan; Adjust threshold to get to a few kHz of triggers
    • 1 uA on LH2 target
    • Take 7 ~5 min long runs with different GEM HV settings for quick voltage scan
      • GEM expert driven ONLY (ensure GEM expert on shift; or call RC if not sure)
      • Voltages: 3653, 3608, 3564, 3519, 3475, 3430, 3385
Confirm Production Threshold Settings in BBCal and HCal
  • GEM Rate Study
    • Ensure GEM HVs are back at standard settings; detectors should be at Production settings
    • SBS ON (2100A pos.), BB ON (750A neg.)
    • BBCAL threshold 2.0 GeV (-400 mV) -- want a nominal 100k triggers/run
    • LH2 target
    • I=1 uA ; take 1 30min run
    • I=15 uA ; take 1 30min run
    • I=5 uA ; take 1 30min run
    • I=1 uA ; take 1 30min run
  • Move to Production Running cycle
    • SBS ON (2100A pos.), BB ON (750A neg.)
    • BBCAL threshold 2.0 GeV (-400 mV)
    • HCAL threshold ~0.5 GeV (-80 mV)
    • Goal: HCAL calib
      • LH2 Target; I = 15uA
      • 10M triggers (nom. 1 hr)
    • Goal: Production
      • LD2 Target; I = 8uA
      • 40M triggers (nom. 4 hr)
    • Goal: HCAL calib
      • LH2 Target; I = 15uA
      • 10M triggers (nom. 1 hr)
    • Goal: Production
      • LD2 Target; I = 8uA
      • 30M triggers (nom. 3 hr)
    • Goal: Production/Dummy
      • Dummy Target; I = 15uA
      • 2.5M triggers (nom. 0.5 hr)
  • This nominally takes us to Friday 11/26 in the SBS-11 Runplan (PDF) document. Progress will be reassessed and subsequent runplan updated as needed.

Reminders / Notes

  • Role sharing between SL and TO was discussed
    • TO should support the SL wherever possible while still keeping primary focus on the target
      • Beam Time accounting; Shift Checklist tasks are low-hanging fruit
      • Suggestion is to have TO start/stop runs and maintain the Run Log spreadsheet?
  • Run plan communication / documentation will be 'officially' documented on the Daily_Meetings#RC_Meetings page
    • Don has made the Run Coordinator 'Run Plan / Report' page more visible on the wiki (and nicely formatted it)

Subsystem Updates

  • Hall A left side camera not responding (can't switch to it) [11]
  • HV Questions/Issues
    • BB hodoscope HV issues [12] (Steve, Ralph?)
    • HCAL HV status display glitch? [13] -- Cause understood. Due to 'Crate OFF' button being used. Largely cosmetic
  • HCal:
    • Present data on HCal detector calibrations (timing, energy calibration and uniformity over acceptance, coordinate resolution) at upcoming meeting
    • Working on clustering in SBS offline
    • Will be using old HVs for SBS-11 startup
  • BBCal:
    • New HV settings made for upcoming BB/SBS on/off settings
      • Contact BBCal experts [Arun] to load these and monitor BBCal performance during beam restart
    • Cosmics runs in SBS-11 configuration with magnets on: [14]; significant fringe field gain suppression in PMTs
      • HVs adjusted and uploaded [15]
    • Parts arrived for PMT dry-air flushing system; needs SSG support
  • Timing hodoscope:
    • Working on RF alignment
      • Rachel gave a status update online and will post to the halog
      • Been working through analysis related issues; making progress; several issues remain in presentation
      • Mark suggested he may need to write a new class to handle the RF time and make it easier to work with within the analyzer
  • Grinch:
    • Study of LED data taken under different BB+SBS conditions underway
    • Maria/Todd/Bradley will be taking some more opportunistic LED pulser data tonight (Monday)
    • Status update on LED data to Halog was requested
  • GEMS:
    • GEM experts will be monitoring the gas bottles over the holidays (should be fine, but extra eyes will help)
    • GEM HV Cosmic Scan Status
      • No analysis of these runs yet -- many had bad latency; may not be useful...
    • Work continues on calibrating/understanding the new GEM layer
      • Andrew reports things seem to be generally working, but some issues still being worked on
      • Still investigating the following: large number of fake tracks; possible issues with pedestal suppression, or perhaps indication of cross-talk; unclear... (this hypothesis is still under test)
      • GEM "HV-off" cosmics data are on disk -- not clear if it has been looked at (may help disentangle potential cross talk sources)
    • DAQ latencies issues noted in the GEMs seem to be global and caused issues with data taking throughout the night
      • It is still unclear why these changed [16], [17], but latencies are being adjusted based on what we are seeing this morning: HCAL, GEM, UV GEMs, BBCAL, BBHod, BBGrinch seem to be OK now
  • Beamline:
    • David F is looking at scaler sanity checks with Paul
  • DAQ:
    • Need electronics, timing diagrams that represents 'as-built' system
    • Latency shift was discovered to be common to entire DAQ
      • Seems to have changed around the time the ROLs were updated; which was around the time of some library updates
    • Latency configurations seem to be a mess based on comments in Slack (scattered across many files, interactions between global and 'local' settings, etc)
      • At minimum, this should probably be documented on the wiki?
  • Replay analysis:
    • GEM work is ongoing (see above)
    • Eric working on end-of-run report file output along with Dave F.
      • Would be great to summarize total Charge on target, 'good event' statistics, as well as summarizing efficiencies and other QA related parameters?
      • Probably most useful for full replays? (Online histo display should cover most/all of what the shift crew need to monitor already?)
    • Online analysis golden runs -- what do shift crew check run-by-run?
      • Generate a stripped-down set of plots for shift crew monitoring; experts can use a different Panguin config with a full set of plots?
    • Plan for full analyses on Farm?
      • This seems to be one of the items holding up more complete analyses of prior data
      • Sounds like a plan needs to be hammered out and implemented?
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