RC meeting and Run Plan, Tuesday Sept. 19, 2023

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RC Meeting Information

Time:at 3:30pm today

• Location: Counting house conference room

• ZoomGov Meeting Connection Information

https://sbs.jlab.org/cgi-bin/DocDB/private/ShowDocument?docid=431

Useful Links

• MCC White Board

Procedures

Hall A call-in instructions:

• Call RC first.
• Techs on site 7-4:30 Mon-Th, 7-11AM Fr. RC will call Hall A work coordinator (Zak) during normal working hours. After hours, RC calls Tech on-call.
• After 9pm everything non-emergency needs to be deferred. What is emergency and what's not? Call RC. RC talks with Mark to decide.

Hall Access procedure:

• Access check list (binder on the counting room desk) needs to be filled out before making an access.
• Scan (take pictures with phone) and post it to the logbook.
• Any work inside the SBS, BB boundary need to have PS locked out -- requires two QEWs to throw the big switch. Exception: field measurements.

New instruction for shift crew when changing target:

• Beam restoration instructions have been updated. Printed version is in the counting room.
• When we chnage target, make sure the SOFs of Target BPMs are set to the correct values.
• SOFs for different targets: https://logbooks.jlab.org/entry/4179164 (Note: SOFs for "No Target" has been updated and they are same as the He3 target values)

Readiness for Beam

Acclerator status

• A few hours of downtime during swing: 1C05 trip magnet regulation fault, PS replaced (https://logbooks.jlab.org/entry/4182290). ABU+BANU: 2.5+1.0 = 3.5hrs.
• Downtime during the daytime mostly due to RF issues. AB+BANU: 5.1+0.6 = 5.7hrs
• Took 30uA beam for swing and owl. Got 30-36uA during the day shift. ABU+BANU: 3.1+0.7 = 3.8hrs

• Charge collected:

- Swing: 0.225C - Owl: 0.288C - Day: 0.244C

Subsystems Checklist

For each subsystem we ask that the responsible person go over the following points:

1. The overall status of your subsystem
2. Will your subsystem be ready well before Hall lock-up on Friday or at the latest by Monday morning?
3. Does your system being ready depend on your team only or are outside resources required?

Subsystems

• SBS magnet and Bigbite magnets
  • work as expected
• Corrector magnets:
  • work as expected
• Target status (magnets, measurements, laser, installation, alignment, polarization, power etc)
• HCal (Jiwan Poudel)
  • VME DAC GUI does not read the correct threshold -- pending issue to be fixed
• Bigbite (Arun Tadepalli)
• Counting House Alarms (Bill Henry)
• DAQ (Alex Camsonne)
• GEMs (Holly Szumila-Vance)
• Moller polarimeter (Don Jones)
  • Hall C is going to do the Moller measurement tomorrow.
• Hodoscopes (Rachel Montgomery):
  • Hodo status ok. Will fix two bottom bars with low efficiency.

Task list during the access, Tuesday 9/20

• Please let SL know that you are going down to the hall, where to work, and after you are done.
• Make a HALOG entry summarizing the work
• Start early in the morning if possible, to reduce the interference with the laser work (put the hall in CANS mode)
• List:
  • SBS PS acid flushing. Crew will be there as soon as we can get into the hall
  • Target work
  • Sean: BB GEM Layer 3 (~2h)
  • Jiwan: HCal (a few channels missing TDC)
  • Alex: TS crate, GRINCH FAN VXS reboot, threshold RPi monitor
  • Ellen: Grinch bottle weight readback
  • Ralph: Hodoscope (bottom two blocks with low efficiency)
  • Don: Moller target magnet
  • Jimmy: ECal HV crates. DSG will do some work on the ECal heater prototype

Shift schedule

• Looks much better! Just a couple of slots to fill next week (DAY, SWING).

Run plan

• Take production data until tomorrow morning, up to 36uA.
• At around 6:50am tomorrow, beam off and ramp down SBS and BB magnets before the access.
• Hall open around 7:30-8AM.
• After the access, restore the CW beam. Check Carbon hole data and do the target centering.
• Also check the detector plots in the meantime.
• Bring up the current up to 45uA on He3 if possible.
• Take data with glass cells overnight.

List of items in case target isn’t ready:

1. Take data on reference cell at 10 atm H2 (portions that add up to 1 day)
2. BigBite Sieve slit => only during day (Techs needed)
   1. with 8 carbon foils and take optics for 1 hr at 40 uA (Sean/Andrew - confirm time)
   2. 1 hour for single foil (magnets off) => Chance BBcal HV setting to appropriate values
3. Moller measurement
4. BigBite/single foil location reconstruction (~20 mins?) - BigBite + HCAL detector experts on call consulting analysis experts like Andrew/Sean (magnet on)