RC Update and Run Plan for Aug 20, 2020

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RC Meeting Information

RC Daily Meetings are at 4:15 PM, remote

General updates

  • Todd's Access, He3 refill at 6:45pm
  • Reference cell run: 6 hours
  • Magnet polarity change
  • Positron run (SHMS at 11 degree, P=+7.5 GeV): 1.5 hours
  • Moller is still going

Pending problem(s) / Things to track

Recent polarization measurements

  • OWL (08/20) 2:30 - 29%
  • OWL (08/20) 12:20 - 10%
  • OWL (08/20) 14:51 - 19.5%

Current Run Plan

Normal Production running

  • Prerequisites
    • Make sure the raster size is correct (4--4.5mm)
    • Monitor beam parameters/configuration very often and post an entry like this at the beginning of your shift and when run conditions have changed
    • Running on cell targets: raster always ON (4--4.5mm, size will be determined by the scraping checks), orbit locks ON, current ramp rate 1 muA/sec
    • Always take 120Hz of EDTM
    • Fill the BTA with realistic numbers. If the desired beam current is not delivered prorate your ABUs!
    • Change the IHWP at least every 8 hours when running on glass cells. If Hall A hasn't changed in 8 hours, call the RC
  • Run plan
    • Complete the Moller measurement (still 4-6 hours of work remain), while keeping an eye on the target polarization.

Notices in Effect for Shift Crew

  • Follow all COVID rules and regulations as well as remind each other.
  • Beam positions: [1]
  • Policy for CANS-related hall status change: Make a logbook entry when the hall goes in, or comes out of laser-controlled access.
  • Inform the RC of any access that the Target Team requires. The RC will coordinate with RadCon to make everything run smoothly.
  • Please make sure that the orbit locks are enabled and the beam does not drift from its nominal position.
  • Ramp rate lock instructions are here and added to checklist[2]
  • An new reference Cell refill procedure: New procedure
  • Magnet policies
    • Spectrometer GUI (go_magnets) should always be visible on Shift Leader computer, hcdesk3
    • Slow ramping procedure of the SHMS, go small steps to the MOL, an great example (1 hour 30 min process)
    • HMS Q1 must be ramped down in 50A steps in all cases
    • Do not ramp HMS Q2 to zero, only go to 10A and then switch off power.
    • If any of the Spectrometers magnets trip, take a screenshot of the PSU window and check the hall for smoke or water with the camera before resetting the interlock and post it to hclog.
  • New SHMS matrix element

Planned Accelerator Configuration Changes

  • Hall C to 1st pass on 8/31 and back to 5th pass on 9/03


  • Bluejeans remote connection information:
 To join the Meeting:
 https://bluejeans.com/861439920
 To join via Room System:
 Video Conferencing System: bjn.vc -or-199.48.152.152
 Meeting ID : 861439920
 To join via phone :
 1)  Dial:
   +1.408.740.7256 (US (San Jose))
   +1.888.240.2560 (US Toll Free))
   +1.408.317.9253 (US (Primary, San Jose))
   (see all numbers - http://bluejeans.com/numbers)
 2)  Enter Conference ID : 861439920
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