How to recover BPM positions after llong beam trip

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Follow this procedure only if beam is down for more than 2 hours or if there are any tune changes (ask MCC if in doubt)

  1. When beam is back, check to see if the beam positions are back to previous good BPM values.
  2. Move to 12C (carbon hole) target
  3. Ask MCC to turn OFF fast raster and tell them you are going to turn ON slow raster (50nA).
  4. Change slow raster size to 1.4 cm (1.1 volts on function generator)
  5. Center 12C hole by changing BPMs if necessary
    1. Do spot_L and spot_3
    2. X and Y on the spot_L/spot_3 are same as beam except Y axis is reversed.
    3. Halog all raster plots
  6. If 12C hole is centered. Note down the BPM values and move to 12C-40 target
  7. Ask MCC to turn ON fast raster and increase the slow raster size to 2cm (1.45 volts)
    1. Do spot_L and spot_3
    2. If beam hits something, then decrease the slow raster size to 1.8cm
    3. Halog all raster plots
  8. If raster pattern looks good (no hotspots) on 12C-40 then move to NH3 production target
    1. Do spot_L and spot_3
    2. Halog all raster plots
  9. Check 3rd arm trigger rates. For 2.2 GeV beam with 50nA on NH3 target the rate should be 2-3 KHz and DT < 20%
    1. If rates on 3rd arm are very high and DT >> 20% , call RC.
    2. Otherwise you are all set for production!