RC meeting and Run Plan, Thursday December 2nd

Daily_Meetings

RC Meeting Information

Run Coordinator: Eric King

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

Accelerator and Hall Status:

• (Accelerator) Maintenance day yesterday. Spot move on cathode.
• (Accelerator) Burst chilled water pipe used for service building AC went down event_14651 (resolved around 6:45pm) followed by a FSD error that prevented startup until about 8:45pm.
• (Accelerator) Fuse needed to be replaced, machine down for 3+ hours event_14731.
• (Hall) Work completed around 4pm and returned back to beam permit.
• (Hall) Unser calibration data taken [1]; offline analysis to be completed.

Runplans

• (12/1) SWING: (LH2) Finished up 10M triggered events.
• (12/2) OWL: (LD2) Work towards 80M triggered events 10M/run or max 2hr.
  • Only ~20M accumulated over OWL shift.
• (12/2) DAY: (LD2) Continue with LD2 for the moment. Will need to do 30 min on dummy. Then on to cycle 2. We've just about finished LD2. Will move onto empty can at beginning of SWING.

Resolved Issues

• Low trigger rates HAL1A alarm (Called Alexander and resolved problem) [2] [3] [4]
• Moller polarimeter shutdown [5] -- Alarm panel still going off. Let Simona know limits would be changed [6] and changed limits this morning [7].
• UV GEM Layer 2 in bad state. Resolved by Sean [8].

Unresolved Issues

• [cause unknown] GEM Layer INFN J0 common mode drifting
• [cause unknown] Latency shift in BigBite of ~70ns [9] [10] [11] [12]
• Horoscope HV alarms going off [13]; I created a HALOG entry and tagged Ralph/Rachael [14]. Apparent repeat of issue on 11/25 [15]. Ralph came in to double check the issue and make sure it wasn’t a hodoscope problem. I contacted Stephen Wood, and Ralph is working on a possible solution.

Subsystem Updates (From Meeting)

1. HCal
1. Development of method to more easily identify latency shifts ongoing.
2. BBCal
1. RaspPI -> Dedicated Power Supplies -> Remote Controlled
1. Tested
2. Wiki updated! :)
3. Timing Hodoscope
1. Data looks fine over the past couple weeks.
2. HV alarms are not a hardware issue. Software control issue that will be looked at Friday or Monday (Ralph will be coordinating with Stephen Wood).
3. Opportunistic hall access desired to remove card. Card will remain in hall.
4. Grinch
1. Nothing of importance.
5. GEMS
1. MPD Bad State on UV GEM Layer 2. (Logbook link under 'resolved issues' above.)
6. Beamline
1. No important updates. See log entry by Bob Michaels here about near-completed effort on charge script.
2. Unser calibration ongoing... (see link above under 'Hall Status').
7. Replay analysis
1. Full Replays of LD2 data from 1-2 nights ago. Issues of negative polarity fluctuations in GEM signals has implications for GEMS at higher currents.
2. The sag issue is proportional to beam current and it would probably be safest to keep LD2 at 8uA beam current.
3. No current understanding of the cause of this issue. Xinzhan suggested reducing GEM buffering from 4 to 1 (in an effort to perhaps gain some insights into the cause).