RC meeting and Run Plan, Wednesday October 26th

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Return to the RC Meeting Calendar

RC Meeting Information

Time:at 3:30pm today to accommodate Hall C weekly meeting

  • Location: Counting house conference room

Useful Links

Current Status

Polarized Target

  • Current Polarization ~ 32%
  • Laser module changeout by Jack : [1]
  • 3 laser interlock trips during OWL (Thanks Arun for coming in to reset them!): [2]
  • Update from Gordon: [3]
  • Polhe1 and Polhe4 need to include Microsoft update exemptions so they do not automatically update and reboot.

RF Recovery

  • It was decided to have an (short) RF recovery tomorrow on DAY shift from 8:00 am - 12:00 pm
  • Radcon can support a survey at ~ 9:00-9:15 am

Hall A Walk-Through

  • Hall A walk-through training (Jessie and Rachel)

BCM and Unser

  • Keith Cole and Dave Mack: When the beamline loses vacuum and is then pumped back down, BCM & Unser are detuned. Keith Cole could support a retuning of the Unser if there is an RF recovery
  • Dave Mack: For an asymmetry, the current BCM calibration would be fine. For cross sections.... may want another BCM calibration.
  • During controlled access, Keith Cole's group would need 1 hour to retune the Unser (2 People)

Moller Q3 polarity

  • Jim Coleman could swap the leads to the Q3 Moller quad. Will take ~45 minutes and require 2 people
    • This could be done during the configuration change

SBS Standalone DAQ

  • Alexander. 30 in?
    • This could be done during the configuration change

SBS GEM gas readout

  • Jack can could the rPi during the controlled access

Other Topics

  • OPS and RF would like to study the ramp rate in Hall C while observing their ramp rate. This can be done in a dedicated beam studies, in which "parasitic beam" could be delivered to the halls. Jay anticipates the "parasitic beam" would be similar to what we are receiving now for production but likely with a higher trip rate. The test duration would be no more than 4 hours.
    • If it cannot be done due to Hall A's ramp rate (1 uA/s), they wonder if the ramp on the polarized helium-3 cell could be raised? To ~1.5 uA/s? Switch to a non-glass cell during this period?
  • Estimate of the total fraction of events collected?
    • Accumulated charge corrected for target polarization: 3.9 Coulombs
  • Excel spreadsheet created to track the DAQ crashes their sources was setup.
  • Subsystem updates?


  • Configuration and pass change moved to Monday (10/31/2022): [4]
    • Swapping of the leads to the power supply of the 3rd Moller quad
  • Opportunistic BCM calibration (higher current) before pass change (only if Unser is detuned)?

Current Run Plan

For Monday swing and Tuesday OWL we will be focusing on polarized helium-3 production.

Run Plan 1.) He-3 runs, at 45uA of beam current. Use ps3==0, ps5=12, all others -1. Take four runs that should each last for one hour. 2.) Move the target to the pickup coil position, and the TO should run an NMR sweep to measure the polarization. 3.) Return to step 1.)

  • Keep an eye out for drifting BPM positions
  • Log all DAQ crashes in the excel worksheet along with the reason for the crash
  • If beam delivery is interrupted for more than 4 hours, perform a checkout of the beam profile and raster follow Simona's procedure: [5]
  • Cross check the rate with what is expected: [6]
  • Cross check with the expected ion chamber readings: [7]

Notices in Effect for Shift Crew

Current Issues

  • Shift Openings: [8]


Planned Accesses to the Hall

Special Requests

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