Tune Photon Beam
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Tune Electron Beam
Tune Photon Beam
- Goal: Tune the photon beam to go through the collimator, the experimental target area, and into the photon beam dump.
- Responsibility: HallD, Accelerator, RadCon.
- Priority: Most activities are High, but includes Moderate and Low priority activities.
- Conditions:
- Tagger hall equipment removed or shielded. This includes the microscope (TAGM) and the electronics.
- Beam 50nA CW.
- Radiator 1.1·10-4 RL.
- The 5mm collimator hole is at nominal beam position.
- Profiler installed in Hall D collimator cave. Small calorimeter in back of 3.5 mm hole (is such calorimeter necessary if we are likely to have a CW beam?).
- Pair spectrometer field on, converter retracted.
- Solenoid on with current ~1000A.
- GlueX detectors off (except peripheral such as BCAL)
- No target in place (use air along beamline as target).
- Activities
- (High) (Accel., HallD) Use the beam profiler and/or active collimator to move the photon beam to the hole in the collimator.
- Both the photon beam position and angles can be controlled using the last quadrupole's correctors on the electron line.
- To what accuracy do we know the the motion due to the corrector (Todd S.)?
- (High) (RadCon/Hall D) Check radiation levels in the collimator cave and HallD.
- (High) Calibrate accelerator scale (calibrate the quadrupole's correctors in term of beam position at the profiler).
- (High) (HallD) Turn the PS magnet on and install a 10-3 converter. Tune the PS coarse detectors.
- (High) (HallD) Use the PS wire scanner and the coarse detectors to verify the beam location.
- (High) (HallD) Insert a convertor in the PS and leave running with its own trigger throughout the run period.
- (Moderate) (HallD, Accel.) Calibrate the active collimator by using the calibrated accelerator scale. Check the calibration by moving the collimator slide.
- (Under discussion) (HallD) Install the profiler in front of the GlueX detector to verify beam position. Another possibility is to monitor for azimuthal asymmetries in the start counter.
- (Low) (HallD) Use beam line detectors (under discussion) and radiation devices to verify the beam position with respect to the beam pipes and the target.
- (High )(HallD) Install profiler in front of beam dump to verify that the beam is centered on the dump.
- (High) (HallD) Turn detectors on slowly, moving in from the peripheral to the center. Monitor the rates and background levels.
- (High) (HallD) Insert the CH2 cup target at the nominal target position. Set the regular trigger and monitor rate changes as the beam is scanned vertically and horizontally .
- (High )(HallD) Insert a thin target at the nominal target position. Set the regular trigger and take data for about 1 shift.
- (High) (Accel., HallD) Use the beam profiler and/or active collimator to move the photon beam to the hole in the collimator.