Tune Photon Beam

Tune Photon Beam

1. Goal: Tune the photon beam to go through the collimator, the experimental target area, and into the photon beam dump.
2. Responsibility: HallD, Accelerator, RadCon.
3. Staffing:
4. Priority:
5. Conditions:
   • Tagger hall equipment removed or shielded. This includes the microscope (TAGM) and the electronics.
   • Beam 50nA CW (if possible).
   • Radiator 10^-4 RL.
   • Collimator hole is 3.5mm at nominal beam position.
   • Solenoid on with current ~1000A.
   • GlueX detectors off (except peripheral such as BCAL)
   • No target in place (use air along beamline as target).
6. Activities
   • Use the beam profiler to move the photon beam to the hole in the collimator. (Accel, Hall D)
   • Check radiation levels in the collimator cave and HallD. (RadCon)
   • Turn the PS magnet on and install a 10^-3 converter. Tune the PS coarse detectors (Hall D).
   • Use the PS wire scanner and the coarse detectors to verify the beam location.
   • Insert a convertor in the PS and leave running with its own trigger throughout the run period.
   • Calibrate the active collimator by moving the collimator slide (desirable activity). (HallD and Accelerator)
   • Use other detectors (under discussion) to verify the beam position with respect to the beam pipes and the target (if time permits) (Hall D)
   • Turn detectors on slowly, moving in from the peripheral to the center. Monitor the rates and background levels. (Hall D)
   • Insert a thin target at the nominal target position. Set the regular trigger and take data for about 1 shift.