View source for Beam and Raster Checkout for A1n/d2n (Long Procedure)

=== Establish beam in the hall ===
  '''Goals '''
  - Using "Target Out" location, tuned beam only, make sure beam reaches beam dump without hitting anything.

=== Initial Checkout ===
This is the [[Beam and Raster Checkout for A1n/d2n (Short Procedure)]]
{{:Beam and Raster Checkout for A1n/d2n (Short Procedure)}}
  No CW beam should be allowed in the Hall until this step is completed.

=== Target/Beam centering and Raster checkout ===
  '''Goals '''
  - Establish nominal beam position on target and check/confirm raster size

  '''Setup '''
  - Beam Current:   5-10 uA CW
  - Target:         Double Carbon Hole
  - HMS setting: check run plan
  - SHMS setting: check run plan
  - NOTE: It is strongly suggested that the most forward angle spectrometer be set to a low momentum to ensure adequate rate.
  - NOTE: If the beam profile is ''fat'' (> 500 um in X or Y) then the hole may be hard to resolve.

  '''Procedure'''
  - Note:  DAQs should be running and double carbon hole target is in place
  - Online shift crew will proceed with program below.

  - Image Carbon Hole target using Raster current pickoffs vs. raw trigger rates in SHMS and/or HMS
  - Target:    Double Carbon Hole
  - Current:   5 uA CW
  - Raster:    5mm diameter
  - Run DAQ on SHMS / HMS
  - Set PS1=0 and all other PS=-1 to ensure DAQ is dominated by scintillator triggers (i.e. "3 scintillators out of 4" or "3/4" triggers)
  - Run the online analyzer and look at the 'Fast Raster' panel of the online GUI:
  - Locate the hole in the 2D intensity histogram. A rough z cut should be included in the script to show up- and down-stream carbon hole separately.        
  - NOTE: if the beam energy in standard.kinematics is not up to date, the distance scale on the 2D histogram will be wrong
        [[File:hallc-carbon-hole.png|thumb]]
  - Center Beam on using Double-Carbon-Hole Target:
      - Iterate until the hole is clear, and is centered in the circular raster pattern for both up- and down-stream carbon foils
        - Adjust beam position
        - Re-run the online analzyer on the new file(s) to see the effect of a raster size change and/or beam position change.  Make sure changes are logged in the CODA start-run entries!
  - Estimate raster dimensions against Carbon Hole diameter (known to be 2mm diameter).

  - Optional: Run 5uA TUNE BEAM and request a harp scan on target girder. Verify that the width of the rastered beam in the scan is consistent with 5mm diameter raster setup.
  - For an example of complete beam centering procedure using carbon hole, see https://logbooks.jlab.org/entry/3749551

=== Bull's Eye Scan: BPM and Harp cross Calibration (Optional) ===
[[Bull's Eye Scan|Bull's Eye Scan Main Page]]
This is done to cross calibration the BPMs against the Harps.  It is generally done once for an experiment -- confirm with RC before doing this step.
{{:Bull's Eye Scan}}