Finalize Photon Beam Commissioning and Optimize Detector Settings

From Hall D Ops Wiki
Revision as of 18:19, 22 October 2014 by Deurpam (Talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search
  • Goal: Finalize the photon beam commissioning. Verify optimal settings for detectors.
  • Responsibility: HallD
  • Expected Schedule: See start dates in the run coordination meeting pages here and the general schedule here. Expected time for finalizing photon beam commissioning and optimizing detector settings 2.5 days
  • Conditions:
  1. Hall D controlled quadrupole MQPAD00 remained turned off. \Box
    • Responsibility: MCC
  2. Monitoring available in counting room:
  3. Tagger hall equipment in place and operating. \Box
  4. Beam 50nA CW
  5. Radiator is 1.7 10-5.\Box
  6. Pair spectrometer field on, converter inserted \Box
  7. Collimator hole is 5mm.\Box
  8. Solenoid on at 300A.\Box
  9. 1st Profiler is removed. 2nd profiler remains in front of beam dump.\Box
  10. GlueX detectors are on.\Box
  11. No target.\Box
  • Activities
  1. Re-establish the beam and measure beam positions at different locations. (Estimated time: 7h with 100% contingency)
    • Re-establish the beam and measure beam position at tagger Dump (electron beam):4h \Box
      • Procedure monitoring beam position at Tagger dump
    • Measure beam position at Active Collimator:30min \Box
      • System expert: Richard Jones/Hovanes Egyian
      • Procedure for reading beam position from the Active collimator
    • Measure beam position photon dump profiler (Hall D): 30min.\Box
      • System expert: Hovanes Egyian
      • Procedure for getting beam position with first profiler
    • Measure beam position at Pair Spectrometer harp (Hall D):30 min.\Box
      • System expert: Alexander Somov
      • Procedure to extract beam position at scanner
  2. Compare the beam position measurements. Consider moving the collimator from the nominal position if deviations of >5 mm are observed (Estimated time: 2h with 100% contingency) \Box
  3. Re-calibrate the Active Collimator in X (use the slide) and Y, without the Profiler in front. (Estimated time: 12h with 100% contingency) \Box
    • Move the collimator 5 mm hole in X, ±30 mm around the center in order to calibrate the Active Collimator X-response. Use 2 mm step size. Leave the collimator in the nominal position (5 mm hole at the nominal center). 10min/steps -> 2h \Box
      • System expert: Richard Jones/Hovanes Egyian
      • Procedure for moving the primary collimator
      • Procedure for reading beam X-position from the Active Collimator
    • Recalibrate x-scale of the Active Collimator \Box
    • Verify that the collimator motion moves the beam spot at the profilers, while monitoring rates on pair spectrometer for scrapping. 1h \Box
    • If the Active Collimator data provides a better position accuracy - move the beam in X accordingly. Time estimate: 10min \Box
    • Ask MCC to move the beam in X ±10 mm around center. Use 2mm step size. Verify that the beam X-position from the Active Collimator matches 10min/steps -> 1h40 \Box
    • Ask MCC to move the beam in Y ±10 mm around center. Use 2mm step size. calibrate the Active Collimator response 10min/steps -> 1h40 \Box
  4. Verification of the y-scale calibration for the Active collimator. (Estimated time: 11h with 100% contingency) \Box
    • 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. \Box
      • System expert: Richard Jones/Alex Barnes
      • Procedure for rotating the active collimator
    • Move the collimator 5 mm hole in X, ±30 mm to calibrate the Active Collimator Y-response. Leave the collimator in the nominal position (5 mm hole at the nominal center) 10min/steps -> 1h40 \Box
    • If Active Collimator data provides better position accuracy - move beam in Y accordingly \Box
  5. Control access (Estimated time: 2h):
    • Rotate back the active collimator (30min). \Box
    • Install the cross target into the central position in Z (time estimate: 1h) \Box
    • Meanwhile, ramp up solenoid to 1000A \Box
      • System expert: Yi Qiang
      • Procedure for monitoring and controlling Soleinoid current
  6. Re-establish beam (30min)
  7. Turn on the detectors to check for azimuthal asymmetries (Estimated time: 20h with 100% contingency) \Box
    • Turn BCAL detector on slowly. Check scaler rates. Monitor the rates and background levels. (time estimate: 1h) \Box
      • System expert: Elton Smith
      • Procedure for turning on BCal
      • Procedure to check rates
    • Turn Start Counter detector on slowly. Check scaler rates. Monitor the rates and background levels. (time estimate: 2h) \Box
      • System expert: Mark Ito
      • Procedure for turning on Start Counter
      • Procedure to check rates
    • Turn FCAL detector on slowly. Check scaler rates. Monitor the rates and background levels. (time estimate: 1h) \Box
      • System expert: Manual Lara
      • Procedure for turning on FCal
      • Procedure to check rates
    • Turn TOF detector on slowly. Check scaler rates. Monitor the rates and background levels. (time estimate: 2h) \Box
      • System expert: Mark Ito
      • Procedure for turning on the TOF
      • Procedure to check rates
    • Turn CDC detector on slowly. Check scaler rates. Monitor the rates and background levels. (time estimate: 2h) \Box
      • System expert: Benedikt Zihlmann.
      • Procedure for turning on CDC
      • Procedure to check rates
    • Turn FDC detector on slowly. Check scaler rates. Monitor the rates and background levels. (time estimate: 2h) \Box
      • System expert: Lubomir Pentchev
      • Procedure for turning on FDC
      • Procedure to check rates
  8. Check detector rates (time estimate: 2h) \Box
  9. Move the collimator ±10mm and check the rates on the Start Counter (time estimate: 30min) \Box
  10. Minimize possible azimuthal asymmetries by adjusting the collimator or target assembly (time estimate: 4h) \Box
  11. Verify the standard BCAL vs FCAL trigger (timing and thresholds) - about 4h
  12. Take one shift of data. Reconstruct target profile (8h) \Box
  13. Establish beam purity. (time estimate: 2h10) \Box
    • Remove the radiator (5 min). \Box
      • System expert: Hovanes Egyian
      • Procedure for inserting radiator
    • Run with radiator off (1h).
      • Verify rates with on Pair Spectrometer, profiler and radiation monitor in the collimator cave. (With a 10-5 halo and assuming it hits 103 more RL than the central beam, we should expect rates at ~% of the rates with radiator.
      • Establish with Pair Spectrometer the energy spectrum of the photons. Compare with energy spectrum when radiator is on.
        • System expert: Alexander Somov
        • Procedure for running Pair Spectrometer DAQ
        • Procedure for obtaining photon energy spectrum

Back to main Fall14 commissioning page