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  • Once the target cool down started and D. Meekins gives "Go", start ramping up HRS magnets
  • Start with all detector HVs off
  • Start a new fresh slug for the production to separate the data from the previous target

Beam Restoration

  1. Do injector match check before restoring the beam
  2. Target at Home position
  3. Establish tune beam and low current CW beam in the hall (straight through, empty target)
  4. Design match to hall expected as part of original configuration
  5. Verify spot size at the target from harp trace
  6. Once the low current beam is established, check target alignment Before the ion chamber calibration
    • -> Go to Low current checkout #1
  7. May have new target lock positions from the target alignment check
  8. Establish 30uA to dump, ion chamber calibrations to 30uA on Ca40, Carbon, Ca48.
  9. Establish high current beam to dump with Carbon 1%
  10. Ramp current in steps to 150uA on Ca40, check if the trip point makes sense
    • this involves target burn-off
  11. If Yves is available, tune beam through Compton chicane
  12. Do PQB check when we have beam in the hall

Low current checkout

Bob, Chandan, Devi, Silviu,

1. Target verification and raster check:

  • Verify cold target positions and raster size
  • Carbon hole, 1-2uA, 4x4 raster, turn ON S0 HVs
  • Take spot runs, verify the hole and 2x2 raster size (Carbon hole radius :2mm)
  • Compare with the previous C-hole center position.
  • If don't find the carbon hole, adjust BPM positions and raster size
  • Move to Ca40, 4x4 raster, find the target center position (move beam to see the edge and estimate the center). Log it.
  • Center beam to colimator center, 2x2 raster, verify nothing hitting edges, uniform distribution from spot runs
  • Move to Ca48, 4x4 raster, find the target center position. Log it.
  • Center beam to collimator center, 2x2 raster, verify nothing hitting edges, uniform distributions from spot runs
  • Adjust the target ladder to match the horizontal center to the collimator center (consult with Silviu, need to update encorder table before any further target movement)
  • Provide the target positions to Yves, establish the new target lock positions if needed

2. Detector alignment check: Devi, Ryan

  • US and DS detectors to counting mode (done)

3. Q2 measurement:

  • Check magnet setting is right
  • Make sure VDC HVs OFF
  • Beam centered at collimator (if there is new target lock position use that), 2x2 raster
  • Ask <1uA, adjust current to have S0 trigger rate ~100kHz to turn on VDC HVs
  • Take 3M events
  • Take escorted access to switch the detector mode before going to high current checkout
  • Turn off all HVs, make sure to adjust the quartz HVs for integrating mode

High current checkout

1. Low current BMW safety check: Ye (Victorian if it happens during owl)

  • 10-15uA

2. Target burn-off: Shifter, Cameron (Silviu)
During this procedure,

  • Verify the data while taking each run
  • Check if the ion chamber trip point is sensible
  • Monitor the target!
  1. Insert Ca40 target
    • 2x2 raster, run in steps of 30uA (each step for 1h)
    • Monitor detector yields and asym width
  2. Insert Ca48 target
    • 2x2 raster, run in steps of 30uA (each step for 1h)
    • Monitor detector yields and asym width