Difference between revisions of "Tune Photon Beam"

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==[[Tune Electron Beam]]==
 
==[[Tune Electron Beam]]==
 
==Tune Photon Beam==
 
==Tune Photon Beam==
−
# Goal: Tune the photon beam to go through the collimator, the experimental target area, and into the photon beam dump.
+
* Goal: Tune the photon beam to go through the collimator, the experimental target area, and into the photon beam dump.
−
# Responsibility: HallD, Accelerator, RadCon.
+
* Schedule: Start Oct 10 2014, 4 days
−
# Priority: Most activities are High, but includes Moderate and Low priority activities.
+
* Responsibility: HallD, Accelerator, RadCon.
−
# Conditions:
+
* Priority: Most activities are High, but includes Moderate and Low priority activities.
−
#* Tagger hall equipment removed or shielded. This includes the microscope (TAGM) and the electronics.
+
* Prerequisites:
−
#* Beam 50nA CW.
+
# Hall D: Detectors turned off. Exceptions: Profiler, possible BCAL, outer rings of the FCAL
−
#* Radiator 1.1&middot;10<sup>-4</sup> RL.
+
# Collimator: blocking position (similar to the electron beam tune phase). The motion must be calibrated.
−
#* The 5mm collimator hole is at nominal beam position.
+
# Profiler installed in the Collimator Cave, surveyed in order to find the position of the nominal beam center
−
#* Profiler installed in Hall D collimator cave.
+
# Pair spectrometer field on, converter retracted.
−
#* Pair spectrometer field on, converter retracted.
+
# Solenoid on with current ~300A.
−
#* Solenoid on with current ~1000A.
+
# No target in place (air and material along the beamline makes a few R.L.).
−
#* GlueX detectors off (except peripheral such as BCAL)
+
 
−
#* No target in place (use air along beamline as target).
+
* Activities
−
# Activities
+
# (High) Re-establish the CW electron beam 50 nA to the Tagger Dump (Accelerator)
−
#* (High) (Accel., HallD) Use the beam profiler and/or active collimator to move the photon beam to the hole in the collimator.
+
# (High) Insert the 1.7&middot;10<sup>-5</sup> R.L. and check the radiation levels in the Tagger Hall and the Collimator Cave (Hall D/Accelerator)
−
#** Both the photon beam position and angles can be controlled using the last quadrupole's correctors on the electron line.
+
# (High) Using the Profiler find the beam center position with respect to the nominal position (Hall D)
−
#** To what accuracy do we know the the motion due to the corrector (Todd S.)?
+
# (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)
−
#* (High) (RadCon/Hall D) Check radiation levels in the collimator cave and HallD.
+
# (High) Check the electron beam position at the Dump (Accelerator)
−
#* (High) Calibrate accelerator scale (calibrate the quadrupole's correctors in term of beam position at the profiler).
+
# (High) Move the collimator 5 mm hole in X, &plusmn;30 mm around the center in order to calibrate the Active Collimator response. Leave the collimator in the nominal position (0.5 mm hole at the nominal center)  (Hall D)
−
#* (High) (HallD) Turn the PS magnet on and install a 10<sup>-3</sup> converter. Tune the PS coarse detectors.
+
# (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in X accordingly (Hall D/Accelerator)
−
#* (High) (HallD) Use the PS wire scanner and the coarse detectors to verify the beam location.
+
# (High) Move the beam in X &plusmn;10 mm around center, verify the Active Collimator response (Hall D/Accelerator)
−
#* (High) (HallD) Insert a convertor in the PS and leave running with its own trigger throughout the run period.
+
# (High) Move the beam in Y &plusmn;10 mm around center, calibrate the Active Collimator response (Hall D/Accelerator)  
−
#* (Moderate) (HallD, Accel.) Calibrate the active collimator by using the calibrated accelerator scale. Check the calibration by moving the collimator slide.
+
# (Moderate) If the Active Collimator data provides a better position accuracy - move the beam in Y accordingly (Hall D/Accelerator)
−
#* (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.
+
# (High) Install a PS foil converter, turn on the low-granularity PS counters, measure the coincidence rate of two arms (Hall D)
−
#* (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) Using the PS wire scanner and the PS coincidence rate measure the position of the beam spot at the converter (Hall D)
−
#* (High )(HallD) Install profiler in front of beam dump to verify that the beam is centered on the dump.
+
# (High) Insert a PS foil converter, turn the PS detectors on and start taking data - keep the PS running (Hall D)
−
#* (High) (HallD) Turn detectors on slowly, moving in from the peripheral to the center. Monitor the rates and background levels.
+
# (High) Control access: move the Profiler to the location in front of the Solenoid (Hall D)
−
#* (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) Re-establish the beam and measure the position at the Profiler (Hall D)
−
#* (High )(HallD) Insert a thin target at the nominal target position. Set the regular trigger and take data for about 1 shift.
+
# (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) Compare the beam position measurements. Consider moving the collimator from the nominal position if deviation 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) Turn on the Start Counter (ST). Check the rate asymmetry (Hall D)
 +
# (Moderate) Move the collimator &plusmn;10mm and check the rates on the ST (Hall D)
 +
# (High) Set the solenoid current to 1000 A (Hall D)
 +
# (High) Turn on the detectors one by one from the periphery to the center monitoring the rates without and with the beam (Hall D) 
 +
# (High) Control Access: install the cup target (2mm and 7mm thick) into the central position in Z (Hall D)
 +
# (High) Re-establish beam (Accelerator)
 +
# (High) Verify the standard BCAL vs FCAL trigger (Hall D)
 +
# (High) Take 1 shift of data (Hall D)
  
 
==[[One Week Pause in Running]]==
 
==[[One Week Pause in Running]]==

Revision as of 03:28, 7 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 (Accelerator)
  6. (High) Move the collimator 5 mm hole in X, ±30 mm around the center in order to calibrate the Active Collimator 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) Control access: move the Profiler to the location in front of the Photon Beam Dump (Hall D)
  17. (High) Re-establish the beam and measure the position at the Profiler (Hall D)
  18. (High) Compare the beam position measurements. Consider moving the collimator from the nominal position if deviation of >5 mm are observed (Hall D)
  19. (High) Re-calibrate the Active Collimator in X (use the slide) and Y, without the Profiler in front (Hall D)
  20. (High) Turn on the Start Counter (ST). Check the rate asymmetry (Hall D)
  21. (Moderate) Move the collimator ±10mm and check the rates on the ST (Hall D)
  22. (High) Set the solenoid current to 1000 A (Hall D)
  23. (High) Turn on the detectors one by one from the periphery to the center monitoring the rates without and with the beam (Hall D)
  24. (High) Control Access: install the cup target (2mm and 7mm thick) into the central position in Z (Hall D)
  25. (High) Re-establish beam (Accelerator)
  26. (High) Verify the standard BCAL vs FCAL trigger (Hall D)
  27. (High) Take 1 shift of data (Hall D)

One Week Pause in Running

Collect Beam Data for Detector Checkout

Optimize Detector Settings

Drift Chamber Alignment

Collect More Regular Data

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