Run plan Monday-day shift → Wednesday owl

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Tentative runplan for Monday-day shift → Wednesday owl

During that time the beam will not be longitudinally polarized.

  1. Monday Day-Tuesday Owl:
    • Target change and repair/improvement: 16h
    • Polarimetry calibrations: 8h
    • Meanwhile, top-off the He3 ref cell pressure to 117 PSIA (optional, check with Jianping). (As of Thursday we have 65 PSIA left in the Ref. Cell, but it is slowly leaking out)
  2. Tuesday Day:
    • ref cell 3He runs (optional). See here for the ref. cell runs on original run plan
      • 1.5 hours of Ref. Cell 3He runs at SHMS/HMS=-3.4/-3.5 GeV. (100mC charge goal i.e. 66% beam efficiency, goal set for 8atm pressure)
      • 0.5h to change momentum settings to SHMS=-2.6 GeV, HMS=-2.9 GeV
      • 1h of Ref. Cell 3He runs at -2.6/-2.9 GeV. (40min beam-on time, goal set for 8atm pressure)
    • ref cell runs: empty, N2, H2 (must). See here for the ref. cell N2 and H2 runs on original run plan
      • Empty Ref. cell (pump to empty).
      • 1.5h of empty Ref. Cell runs at -2.6/-2.9 GeV. (45min beam-on time, 1.5h assuming 50% efficiency.)
      • 15min fill ref cell with N2 at 10 atm.
      • 45min of Ref. Cell N2 runs at -2.6/-2.9 GeV. (30 min beam-on time). Make a note of ref cell gas pressure in Start-Run entry.
  3. Tuesday Swing:
    • continue Ref. cell.runs
      • 0.5h Pump the cell to empty, then fill with 10atm H2.
      • 1.5h of Ref. Cell H2 runs at -2.6/-2.9 GeV. (45 min beam-on time). Make a note of ref cell gas pressure in Start-Run entry.
    • This ends all ref cell runs at -2.6/-2.9 GeV.
    • Resume ref cell runs at -3.4/-3.5 GeV.
      • 0.5h Set momenta to SHMS=-3.4, HMS=-3.5 GeV.
      • 3hours of Ref. Cell H2 runs at -3.4/-3.5 GeV. (charge goal 200mC).
      • 0.5 Pump cell to empty
      • 3h of Ref. Cell empty runs at -3.4/-3.5 GeV. (to be continued in owl shift, with ultimate charge goal of 200mC).
  4. Wednesday owl:
    • continue Ref. cell.runs
      • 1h to finish Ref. Cell empty runs at -3.4/-3.5 GeV. (charge goal 200mC).
      • 0.5h Fill with 10atm N2.
      • 1h of Ref. Cell N2 runs at -3.4/-3.5 GeV. (charge goal: 67mC).
      • 1.5h BCM calibration (non invasive)
    • Assuming 50% overall efficiency we have 4h of spare time before polarized beam comes back.
  1. If we have time left with unpolarized beam (ultra good running efficiency, run time with unpolarized beam extended during Wednesday day shift...), or if polarized cell is not ready for production, we can do