Detailed High current plan

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CREX version

Beamline instrumentation calibration

  1. Check detector alignment and pulse height (Done)
    • 1uA cavity lock
    • 0.2% Carbon
    • 20 nA, cavity locks on and cavities in low current mode
    • VDC on.
    • Check rates, verify pulse height spectra and alignment
    • Modify DAQ to include GEMS. 10 minute run with GEMS.
  2. C-Hole target, verify spot (Done)
    • 20 nA, spot ++ verify raster size
    • harp scan 4e, verify intrinsic size at target
  3. High current - no target (Skip it tonight)
    • verify compton rates
  4. Ramp to SAM Shutter test
    1. Insert Lead Target.
      • Raster 10x10.
      • 20 nA. (Atten 107, slit 15)
      • Cav locks on
      • spot++ verify not seeing edges
      • Set raster ?x? (to get (x.y) = 4x6 real)
    2. go up in current 1uA (5min)
      • All HV off in HRS hut
      • Target lock (0.6mm, 0.4mm)
      • Collimator water temp
      • beamline temperatures
      • Ion chamber (stability)
      • SAM yields
      • BCM and BPM yields, widths.
  5. access to remove SAM shutters, detector to integrate mode.
  6. Ramp to hi current test.
      • cavity bpm back to high current mode
      • All HV off in HRS hut, except quartz
      • Target lock (0.6mm, 0.4mm)
    1. 5uA (review) (10min)
      • Target lock, FFB (monitor bpm SAT)
      • Collimator water temp
      • beamline temperatures
      • Ion chamber (stability)
      • SAM and DET yields and widths
      • BCM and BPM yields, widths.
    2. 20uA (review) (10min)
      • Target lock, FFB (monitor bpm SAT)
      • Collimator water temp
      • beamline temperatures
      • Ion chamber (stability)
      • SAM and DET yields and widths
      • BCM and BPM yields, widths.
    3. 40-50A(1hr)
      • Target lock, FFB (monitor bpm SAT)
      • Aq feedback
      • Collimator water temp
      • beamline temperatures
      • Ion chamber (stability)
      • SAM and DET yields and widths
      • BCM and BPM yields, widths.
  7. Calibration scan
      • FFB ON
      • to 40-50uA
      • SAMs HVs set
      • DETs HVs set
      • PITA scan at end to check det linearities later
  8. BMW
      • tune beam, slow lock on (ad FFB on?), exercise BMW, check no ion chamber trips, check pauses locks and FFB
      • low current 2-3uA, exercise BMW, check BPM signals, check no ion chamber issues
      • target in, low current 2-3uA,exercise BMW, check BPM signals, check no ion chamber issues
      • "ready for high current"


  1. Check the following has been performed
    • 50uA-70uA beam current, through Compton (backgrounds on fingers and Compton photon detector) with no target
    • Establish 4x4 raster. Insert lead target. (low current, ramp up. check collimator water, vary raster size 4x6?)
    • Set Detector and SAM voltages (Dustin M)
  2. Check Conditions OK
    • collimator water
    • thermocouple temperatures
    • radiation monitors
    • ion chamber stability
  3. Setup Locks (these are necessary for main detectors and SAM calibration)
    • Slow Target Lock on 4A, 4E (jmenu->"slow locks"-> Orbit Locks Expanded View -> HallATGT)
    • Fast feedback for HallA on (iocse9)
    • If beam is going through Compton, HallAComLock should probably be on
  4. Coordinate
    • Should Compton and Moller DAQ be running during calibration?
    • Dustin and Devi examining SAMs and Detectors with online analyzer during calibration
    • Juan Carlos/Amali/Adam monitor Compton background rates and run the DAQ?
    • Ye puts Cavity BPMs in high current mode (opsl01 -> menubar->EDM->BPM->BPM Diagnostics DR(12GeV)->HallA BCMs B,C,D -> button -> Expert Controls -> HWReg button -> DACSL1 = 0x1 / 0x1 and DACSL2 = 0x1 / 0x1 -> back out to previous screen XVGA2 = 0 and YVGA2 =0 (for low current do 0x0 and VGA2=30). Do for all 3 BPM Cavs.
  5. Calibration Procedure A: with UNSER
    • start at 70uA for 1min (scandata1==value in BCM0l02)
    • beam off
    • wait for 5sec(for unser to equilibrate), take unser pedestal data point for 30sec (scandata1=0)
    • beam on at 75uA
    • check slow target lock is in position
    • check FFB on for HallA
    • check no bpms are saturated on iocse9
    • wait for 5sec(for unser to equilibrate), take next data point for 1min
    • repeat for 65uA,60uA,55uA,50uA,40uA,30uA,20uA,10uA
  6. Calibration Procedure B: with pre-calibrated Hall BCM (analog upstream bcm)
    • start at 70uA for 1min (scandata1==value in BCM0l02)
    • change current to 75uA
    • check slow target lock is in position
    • check FFB on for HallA
    • check no bpms are saturated on iocse9
    • take next 1min data point
    • repeat for 65uA,60uA,55uA,50uA,40uA,30uA,20uA,10uA
  7. Calibration Procedure C: for BPMs (Compton bpms not yet calibrated)
    • at 70uA, set gains off for iocse9,iocse10 (Hall) iocse11,iocse12,iocse19,iocinse4 (Inj)
    • perform Calibration Procedure B with pre-calibrated Hall BCM