Beam Recovery Procedure

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After beam study or other major down time

  1. Move target to Empty position, let MCC restore the beam.
  2. Move target to BeO/Optics, ask Raster OFF.
  3. Then let MCC tune the beam to our nominal beam position (BPM values are on the white board) with low current (<=2uA). On the monitor, verify the beam is hitting the center of the cross-hair marked on BeO target.
  4. Move target to Empty position, ask MCC to do a Harp Scan, the beam profile should be within 100-300 um (both X and Y sigmas).
  5. Move target back to BeO/Optics position, ask for 4x4 raster (7x5 MCC units) and 2 uA beam. Take a short run using LHRS DAQ w/ T3 only then do spot++ to check raster size.
  6. Move target to He3 position, ask for 2x2 raster size (3x2 MCC units) and 2 uA beam, compare the T3 trigger rate with previous log (posted on the right side of the scaler monitor).
  7. Keep 2 uA beam, change raster size from 2x2 to 6x6 (10x8 MCC units), verify that there is no significant change in the T3 rate. Do spot++ to check raster size and any hot spot.
  8. Once everything looks normal, change raster size back to 4x4 (7x5 MCC units). Ramp the beam to 5.5 uA and compare the trigger rates with previous log (also posted on the right side of the scaler monitor).
  9. Continue production (!!!Make sure the Pre-scale factors are set correctly for production!!!).

After not very short beam down (>1hour)

  1. Move target to BeO/Optics position, ask for 4x4 raster (7x5 MCC units) and 2 uA beam. On the monitor, verify the beam is hitting the center of the cross-hair marked on BeO target. Take a short run using LHRS DAQ w/ T3 only then do spot++ to check raster size.
  2. Move target to He3 position, keep the 4x4 raster size. Ask for 2 uA beam and compare the T3 trigger rate with previous log (posted on the right side of the scaler monitor).
  3. Ramp the beam to 5.5 uA and compare the trigger rates with previous log (also posted on the right side of the scaler monitor).
  4. Continue production (!!!Make sure the Pre-scale factors are set correctly for production!!!).
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