Post-thanksgiving period

Tune Photon Beam

• Goal: Continue detector/trigger/DAQ checkout

• Prerequisites:

1. Hall D detectors on.
2. Solenoid magnetic field at 800A.
3. Monitoring available in counting room:
   • DAQ screens
     • Procedure for bringing up DAQ
   • online monitoring screens
     • Procedure for bringing up online-monitoring
   • slow control screens and alarm handlers
     • Procedure for bringing up slow control and alarm screens
   • Hall D electronic logbook open
4. 1.5 µm Al (1.7·10^-5 R.L.) radiator in.

1. re-establish beam:
   • Initial conditions:
     • Collimator in blocking conditions.
       • Procedure for moving the primary collimator
     • No Radiator.
       • Procedure for moving amorphous radiator
2. Request 50 nA CW beam.
   1. Check that radiation levels (tagger, collimator cave) are good.
      • Typical levels are (for radiator retracted, collimator fully blocking, electron beam current 61.50 nA)

RAD102_P1= 0.170 mrad/hr (tagger area, gammas, between tagger and dump) RAD102_P2= 0.480 mrad/hr (tagger area, gammas, near electronics racks) RAD102_P3= 0.080 mrem/hr (tagger area, neutrons, near electronics racks) RAD101_P1= 0.006 mrad/hr (collimator cave, gamma)

1. 1. Insert 2*10^-5 radiator. Insert 5mm collimator. Check beam position on the Active collimator. Check that radiation levels are good.
      • Typical levels are (for 2*10^-5 radiator, electron beam current 48 [67.5] nA)

RAD102_P1= 3.500 [4.10] mrad/hr (tagger area, gammas, between tagger and dump) RAD102_P2= 9.900 [12.0] mrad/hr (tagger area, gammas, near electronics racks) RAD102_P3= 0.500 [0.75] mrem/hr (tagger area, neutrons, near electronics racks) RAD101_P1= 9.700 [14.0] mrad/hr (collimator cave, gammas, 5mm collimator)

1. 1. Check the beam position at the profiler.