Checklist for Spectrometer DAQ during PVDIS

Experts:   Dustin McNulty, Bob Michaels

updated October 29, 2009

HAPPEX -> spectrometer DAQ

1. Make sure spectrometer DAQ works (might need reboots).   Use the CODA guide if necessary.
2. Do NOT turn on scint or VDC HV yet !
3. Check with spot++ that rastered size is approx 4 x 4 mm (whatever is our present norm.)
4. 1 uA on target (raster on).
5. Adjust HAPPEX Electron Detector HV   (Hint:   record what HV was there first, to make it easy to return later.)
   • Left arm 2100 Volts
   • Right arm 1600 Volts
   • Why different: they are different bases.
   • Later verify the ADC peaks 1000 chan above pedestal.
   Reminder of HV channels
   • Left arm HV is in slot 2, chan 9 (Here, hannel 9 is the 10th channel, its C index style)
   • Right arm HV is in slot 14, chan 9 (Here, channel 9 is the 10th channel, its C index style)
6. Switch HAPPEX to spectrometer DAQ
   • Middle room, bottom of racks CH01B06 (Right) and CH01B05 (Left)
   • Plug in the 12.5 V nearby in the following way
   • Right-HRS for Cnt mode need chan 16   (index here starts at 1)
   • Left-HRS for Cnt mode need chan 11   (index here starts at 1)
7. Check the beam position ("centered" to within 0.1 mm, using the production criterea, see white board).
8. FFB on for energy and position (actually, it might not work at the low currents, so don't push too hard for this).
9. Target in (ONLY AFTER verifying rastered spot size)
10. Scintillator HV on S0 front and back PMTs. -- check rates in xscaler.   Reminder about S0:
    • L-arm S0 in card 2,   Ch1: -1700,   Ch7: -1700
    • R-arm S0 in card 14,   Ch1: -1700,   Ch3: -1700
11. Reduce current to 0.5 uA. Verify the rates decrease by expected factor.
12. VDC HV on (4 kV) if the T1/T3 rates are below 1 MHz. If above 1 MHz do not turn on HV.   In latter case, call an expert.
13. Take CODA run and analyze it as usual.

Spectrometer -> HAPPEX DAQ

1. VDC off.   This is important.
2. Scintillator HV off.   This is important.
3. No leadglass or other standard detector should have HV.   This is important.
4. Switch spectrometer DAQ -> HAPPEX DAQ
   • Middle room, bottom of racks CH01B06 (Right) and CH01B05 (Left)
   • Plug in the 12.5 V nearby in the following way
   • Right-HRS for Integ mode need chan 5   (index here starts at 1)
   • Left-HRS for Integ mode need chan 10   (index here starts at 1)
5. Restore HV for HAPPEX Electron Detector   (This may have changed. Hence it's important to check what HV was there just recently.)
   • Left arm (Det1):   -1600 Volts on slot 2 / chan 9 for ~95 uA beam
   • Right arm (Det2):   -1200 Volts on slot 14 / chan 9 for ~95 uA beam
   • Why different: they are different bases.
6. Spot++ check BEFORE putting in target in at high current.
7. Take data !