Difference between revisions of "Tune Photon Beam"

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(Tune Photon Beam)
(Tune Photon Beam)
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# (High) Move the collimator 5 mm hole in X, ±30 mm around the center in order to calibrate the Active Collimator X-response. Leave the collimator in the nominal position (0.5 mm hole at the nominal center)  (Hall D)
 
# (High) Move the collimator 5 mm hole in X, ±30 mm around the center in order to calibrate the Active Collimator X-response. Leave the collimator in the nominal position (0.5 mm hole at the nominal center)  (Hall D)
 
# (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in X accordingly (Hall D/Accelerator)
 
# (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in X accordingly (Hall D/Accelerator)
# (Moderate) Request an access, rotate the Active collimator by 90 degree. (Hall D). Time estimate: 2h? (get into Hall: 30 min, rotate collimator 5min, leave and close the Hall, 30 min. Restore beam: 10min.  What else?)
 
# (Moderate) Move the collimator 5 mm hole in X, ±30 mm to calibrate the Active Collimator Y-response. Leave the collimator in the nominal position (0.5 mm hole at the nominal center)  (Hall D)
 
# (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in Y accordingly (Hall D/Accelerator)
 
 
# (High) Move the beam in X ±10 mm around center, verify the Active Collimator response (Hall D/Accelerator)
 
# (High) Move the beam in X ±10 mm around center, verify the Active Collimator response (Hall D/Accelerator)
 
# (High) Move the beam in Y ±10 mm around center, calibrate the Active Collimator response (Hall D/Accelerator)  
 
# (High) Move the beam in Y ±10 mm around center, calibrate the Active Collimator response (Hall D/Accelerator)  
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# (High) Insert a PS foil converter, turn the PS detectors on and start taking data - keep the PS running (Hall D)  
 
# (High) Insert a PS foil converter, turn the PS detectors on and start taking data - keep the PS running (Hall D)  
 
# (High) Control access: move the Profiler to the location in front of the Solenoid (Hall D)
 
# (High) Control access: move the Profiler to the location in front of the Solenoid (Hall D)
# (High) Re-establish the beam and measure the position at the Profiler (Hall D)
 
# (High) Control access: move the Profiler to the location in front of the Photon Beam Dump (Hall D)
 
 
# (High) Re-establish the beam and measure the position at the Profiler (Hall D)
 
# (High) Re-establish the beam and measure the position at the Profiler (Hall D)
 
# (High) Compare the beam position measurements. Consider moving the collimator from the nominal position if deviations of >5 mm are observed (Hall D)
 
# (High) Compare the beam position measurements. Consider moving the collimator from the nominal position if deviations of >5 mm are observed (Hall D)
# (High) Re-calibrate the Active Collimator in X (use the slide) and Y, without the Profiler in front (Hall D)
+
# (High) Re-calibrate the Active Collimator in X (use the slide) and Y, without the Profiler in front (Hall D).
 +
# (High) Move the collimator 5 mm hole in X, ±30 mm around the center in order to calibrate the Active Collimator X-response. Leave the collimator in the nominal position (0.5 mm hole at the nominal center)  (Hall D)
 +
# (Moderate) Request control access, rotate the Active collimator by 90 degree. To rotate collimator should take about 5min. Accessing the Hall, leaving it and requesting beam should take 1h. Assumed total time: 2h.  (Hall D)
 +
# (Moderate) Move the collimator 5 mm hole in X, ±30 mm to calibrate the Active Collimator Y-response. Leave the collimator in the nominal position (0.5 mm hole at the nominal center)  (Hall D)
 +
# (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in Y accordingly (Hall D/Accelerator)
 
# (High) Turn on the Start Counter (ST). Check the rate asymmetry (Hall D)
 
# (High) Turn on the Start Counter (ST). Check the rate asymmetry (Hall D)
 
# (Moderate) Move the collimator ±10mm and check the rates on the ST (Hall D)
 
# (Moderate) Move the collimator ±10mm and check the rates on the ST (Hall D)

Revision as of 10:46, 13 August 2014

Main Page

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.
  • Schedule: Start Oct 10 2014, 4 days
  • Responsibility: HallD, Accelerator, RadCon.
  • Priority: Most activities are High, but includes Moderate and Low priority activities.
  • Prerequisites:
  1. Hall D: Detectors turned off. Exceptions: Profiler, possible BCAL, outer rings of the FCAL
  2. Collimator: blocking position (similar to the electron beam tune phase). The motion must be calibrated.
  3. Profiler installed in the Collimator Cave, surveyed in order to find the position of the nominal beam center
  4. Pair spectrometer field on, converter retracted.
  5. Solenoid on with current ~300A.
  6. No target in place (air and material along the beamline makes a few R.L.).
  • Activities
  1. (High) Re-establish the CW electron beam 50 nA to the Tagger Dump (Accelerator)
  2. (High) Insert the 1.7·10-5 R.L. and check the radiation levels in the Tagger Hall and the Collimator Cave (Hall D/Accelerator)
  3. (High) Using the Profiler find the beam center position with respect to the nominal position (Hall D)
  4. (High) MCC moves the beam to the nominal position, separately in 2 projection, using the last corrector. Calibrate the predicted position vs the position provided by the Profiler. (Hall D/Accelerator)
  5. (High) Check the electron beam position at the Dump using the second Beam Profiler (Hall D/Accelerator)
  6. (High) Move the collimator 5 mm hole in X, ±30 mm around the center in order to calibrate the Active Collimator X-response. Leave the collimator in the nominal position (0.5 mm hole at the nominal center) (Hall D)
  7. (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in X accordingly (Hall D/Accelerator)
  8. (High) Move the beam in X ±10 mm around center, verify the Active Collimator response (Hall D/Accelerator)
  9. (High) Move the beam in Y ±10 mm around center, calibrate the Active Collimator response (Hall D/Accelerator)
  10. (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in Y accordingly (Hall D/Accelerator)
  11. (High) Install a PS foil converter, turn on the low-granularity PS counters, measure the coincidence rate of two arms (Hall D)
  12. (High) Using the PS wire scanner and the PS coincidence rate measure the position of the beam spot at the converter (Hall D)
  13. (High) Insert a PS foil converter, turn the PS detectors on and start taking data - keep the PS running (Hall D)
  14. (High) Control access: move the Profiler to the location in front of the Solenoid (Hall D)
  15. (High) Re-establish the beam and measure the position at the Profiler (Hall D)
  16. (High) Compare the beam position measurements. Consider moving the collimator from the nominal position if deviations of >5 mm are observed (Hall D)
  17. (High) Re-calibrate the Active Collimator in X (use the slide) and Y, without the Profiler in front (Hall D).
  18. (High) Move the collimator 5 mm hole in X, ±30 mm around the center in order to calibrate the Active Collimator X-response. Leave the collimator in the nominal position (0.5 mm hole at the nominal center) (Hall D)
  19. (Moderate) Request control access, rotate the Active collimator by 90 degree. To rotate collimator should take about 5min. Accessing the Hall, leaving it and requesting beam should take 1h. Assumed total time: 2h. (Hall D)
  20. (Moderate) Move the collimator 5 mm hole in X, ±30 mm to calibrate the Active Collimator Y-response. Leave the collimator in the nominal position (0.5 mm hole at the nominal center) (Hall D)
  21. (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in Y accordingly (Hall D/Accelerator)
  22. (High) Turn on the Start Counter (ST). Check the rate asymmetry (Hall D)
  23. (Moderate) Move the collimator ±10mm and check the rates on the ST (Hall D)
  24. (High) Set the solenoid current to 1000 A (Hall D)
  25. (High) Turn on the detectors one by one from the periphery to the center monitoring the rates without and with the beam (Hall D)
  26. (High) Control Access: install the cup target (2mm and 7mm thick) into the central position in Z (Hall D)
  27. (High) Re-establish beam (Accelerator)
  28. (High) Verify the standard BCAL vs FCAL trigger (timing and thresholds) - about 4h (Hall D)
  29. (High) Take 1 shift of data (Hall D)
  30. (Medium) Measure the rates and radiation levels with the 11·10-5 R.L. radiator

One Week Pause in Running

Collect Beam Data for Detector Checkout

Optimize Detector Settings

Drift Chamber Alignment

Collect More Regular Data