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Initial Spatial overlap between LPL, VISAR and X-rays

•  This procedure assumes that
  •  the beamline is aligned up to yag3
  •  the slits are aligned to the beam
  •  the yag at TCC has been prealigned with the help of Questar 2 as well (for maximum accuracy) and the pin (the pin is used to measure the LPL spot size and set the plan of interaction)
•  

  Go to the yag at TCC

  Toggle Cloak

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  visible true
  pyRDarktrue

•  Remove the hutch Be CRL
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  Close slits 4 to 50 mic

  Toggle Cloak

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  visible true
  pyRDarktrue

•  Set a cross on Questar 1 screen and write down the X and Y positions in the preset spreadsheet of the experiment
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  Close the pulse picker and reinsert the Be CRL

  Toggle Cloak

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  pyRDarktrue

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  Move to the pinhole

  Toggle Cloak

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  Tweak the position of the pinhole until it is centered on the cross

  Toggle Cloak

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  Save the new pinhole position

  Toggle Cloak

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•  

  Move back to the yag

  Toggle Cloak

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•  Send the VISAR laser with event code 43 and enable the trigger
•  Confirm that the focus of the VISAR provides a sharp and round image on any VISAR cameras (Visar gige 1 and 2)
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  Tweak the focus of the visar position accordingly (50 mic steps is good enough)

  Toggle Cloak

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  visible true
  pyRDarktrue

•  Turn off the VISAR trigger
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  Prepare the system to check the front alignment of the drive lasers

  Toggle Cloak

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  visible true
  pyRDarktrue

•  

  Check spatial overlap of the drive beams ABEF and GHIJ successively by centering the scattered signal on the cross of Questar 1 screen

  Toggle Cloak

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•  Record each positions of the VISAR and drive lenses in the experiment spreadsheet

Initial Temporal overlap between LPL and X-rays

•  

  go to Ti sample

  Toggle Cloak

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  visible true
  pyRDarktrue

•  remove the Be CRL
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  open slit4 to 400 mic

  Toggle Cloak

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  visible true
  pyRDarktrue

•  

  set full X-ray transmission

  Toggle Cloak

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•  

  open the pulse picker

  Toggle Cloak

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  visible true
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  Open the TCC scope

  Toggle Cloak

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  visible true
  pyRDarktrue

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  Set the EVR of the scope to 10Hz

  Toggle Cloak

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  visible true
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•  Set channel 2 to 2 or 5 mV/div
•  Confirm that the X-ray pulse is seen around 60 ns.
•  Average over 100 sweep and save the trace on M2 (from C2)
•  Set the sweep averaging back to 1
•  

  Close the pulse picker

  Toggle Cloak

  Cloak
  visible true
  pyRDarktrue

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  Insert the filter in front of Questar 1

  Toggle Cloak

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  visible true
  pyRDarktrue

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  Set the laser pulse shape to the timing shape

  Toggle Cloak

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  visible true
  pyRDarktrue

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  Send the 10Hz LPL (enable the trigger of the ns slicer) on target at full energy

  Toggle Cloak

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  visible true
  pyRDarktrue

•  Set the channel 2 to 10 mV/div
•  Confirm you see a trace on C2
•  Average over 100 sweep and save the trace on M3 (from C2)
•  Set the sweep averaging back to 1
•  Take a screenshot and post it to the elog
•  Set the channel 2 to 1V/div
•  

  Set the scope to single shot trigger

  Toggle Cloak

  Cloak
  visible true
  pyRDarktrue

•  Further fine timing can be done by using a LiF coated window
  •  Move to the appropriate target
  •  Confirm Be CRL are inserted in the beamline
  •  

    Set the timing of the drive to 0

    Toggle Cloak

    Cloak
    visible true
    pyRDarktrue

  •  

    Confirm that the streak window have zero offset in the window size requested

    Toggle Cloak

    Cloak
    pyRDarktrue

  •  

    Take a single refence only shot to observe the change in reflectivity at the arrival time of the X-rays

    Toggle Cloak

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    visible true
    pyRDarktrue

  •  

    To double check, confirm timing at another step

    Toggle Cloak

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    visible true
    pyRDarktrue

  •  Fine tune the timing is the X-ray trace is not where it is expected using the nstiming.mv function accordingly.

Check Spatial overlap between LPL, VISAR and X-rays on target

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  Start by moving to the desired target (refer to the python manual here for details on the arguments)

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  visible true
  pyRDarktrue

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  Continue by checking the alignment of the drive lasers

  •  

    Set the system in a mode where the laser energy is minimum, the filter is removed from questar 1 and the trigger is enabled

    Toggle Cloak

    Cloak
    visible true
    pyRDarktrue

  •  Confirm you see a scattering signal close to the X-ray cross (342, 561)
  •  

    Move the hexapod X axis to center the beams on the cross and produce a round scattering signal (steps of 50 mic is good)

    Toggle Cloak

    
    

    Cloak
    visible true
    pyRDarktrue

•  Continue by checking the alignment of the VISAR system
  •  

    Adjust the VISAR Z axis to make sure the image is round and sharp (could be set to the value by using the right equation as well). Steps of 50 mic is good.

    Toggle Cloak

    
    

    Cloak
    visible true
    pyRDarktrue

  •  

    Alternatively, move the Z value by exactly the thickness of the ablator + material of interest and add the change in position due to the visar window. To calculate the change use the following command

    Toggle Cloak

    Cloak
    visible true
    pyRDarktrue

Take reference images with VISAR and/or X-rays

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  For 5 references with VISAR and X-rays (at 20% max)

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  pyRDarktrue

Take a driven shot with the LPL

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  For a driven shot at full energy (lpl_ener=1.0), with X-rays arriving 5 ns later (timing=5.0e-9) at full intensity (xray_trans=1) use the following command

  Toggle Cloak

  
  

  Cloak
  visible true
  pyRDarktrue