Compton Old 2016

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The following is a collection of old information that was used for the DVCS Fall 2016 running period (with some parts applying also to Spring 2016 running period)

Special 5-pass instructions

(Update this section)

  1. Insert capacitor (presently stored just behind the Tungsten Collimator Control Box -- JAWS) control box. It's just a BNC terminator with a capacitor on the end: Compton5PassCapacitor.jpg
  2. Add extra lead sych shield #6 in front of photon detector table. Remember to update the wiki if this occurs. ComptonSynchShieldSetup.jpg
  3. Make changes to .flags file

Centering the Beam on the Laser

Open jaws all the way:

   aperture = 43.69 mm
   y center = -3.28 mm

Tell Dave to make the laser stop flipping. MCC may be looking at the Compton rates, so it's a good idea to let them know we are doing a centering procedure, and to ignore the fluctuation in rates for now. Let them know when the procedure is done.

Use the strip tool for this to watch Compton rates (ComptonCentralRate, ComptonCentralRateHigh) as you change the Y beam positioning. This position will change daily, so may need frequent adjustment.

The laser spot is 0.9 mm, so use small incremental steps. Suggested incremental step change: 0.5mm at a time. No need to map out everything; stop when you think you've located the laser beam.

Photon Detector Table

For controls, troubleshooting: Compton Photon Detector

Home position of photon detector table: (Dave insert, please)

Collimator Systems

  • Remote-controlled tungsten collimator system ("Jaws"):
    • EXPERTS ONLY jaw controls: [1]
    • Live Compton camera: [2]
  • Lead cylindrical collimator:
    • Length approx 10 cm with two openings: 1 and 2 cm diameters
  • Synchrotron shielding:
    • 7 individual thin shields that are numbered, with thickness denoted in X.XX mm +/- 0.01mm:
      • #1: 1.56
      • #2: 1.61
      • #3: 1.61
      • #4: 1.62
      • #5: 1.64 <--- currently in (inserted 2016-10-27)
      • #6: 1.64 <--- currently in (inserted 2017-11-10)
      • #7: 1.67

High Voltage Controls

Know the HV channel and navigate to the GUI: HV Control GUI