RC Update and Run Plan for Aug 18, 2020

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RC Meeting Information

RC Daily Meetings are at 4:15 PM, remote

Wednesday Aug 18 2020.

General updates

  • Production continued during SWING and OWL shifts.
  • RF recovery began at 08:00 today. Opportunistic work was preformed in the Hall, including:
    • Work on the SOLID cherenkov
    • Check of the voltage in the hall under full load conditions
  • Temperature study at 90 degrees --- temp_study
  • The holding field was rotated to 270 degrees --- holding_field_rotation
  • Per MCC, we should try not to make requests during the Operator turnovers (8:00 am, 4:00 pm, 12:00 am). The COVID restrictions make these turnovers a little more time consuming and they want to avoid making any errors that could be avoided otherwise. The request is for a 30 minute buffer (~8:30 am).
    • Note this does not apply to immediate/emergency situations
  • We plan to do a Moller measurement on Thursday (DAY). It is on SAD Calendar.

Pending problem(s) / Things to track

  • QWP controls needed to rebooted again... QWP_controls_reboot
  • Target polarization. After the temperature scan, the most recent NMR measurement was only ~ 35%
    • The settings had the wrong angle (90 instead of 270, but J.P. still suspects the polarization is low)
    • Reference cell runs while we wait to take another NMR
  • Beam positions: Have been moving around --beam_positions
  • Web monitor browser isn't opening

Recent polarization measurements

Analysis Update

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
    • When beam returns after the RF recovery, follow the beam and raster checkout beam_checkout.
    • Depending on the time beam returns, we likely will need to take reference cell runs while waiting for the polarized He3 cell to spin up to an acceptable polarization
    • Once the polarization is acceptable, continue taking production data on the polarized Helium-3 target. If not able to reach requested current, pro-rate the ABUs

When there is a Down

  • If Hall will have opening for 1+ hours, let Simona know as there is work to do on the SOLID cerenkov.

Notices in Effect for Shift Crew

  • 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.
  • Magnet policies
    • Spectrometer GUI (go_magnets) should always be visible on Shift Leader computer, hcdesk3
    • 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.
  • 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]
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