Page History

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•  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
  

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  op.yag()

•  Remove the hutch Be CRL
•  

  Close slits 4 to 50 mic

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  op.slit4.move(0.05)

•  Set a cross on Questar 1 screen and write down the X and Y positions in the preset spreadsheet of the experiment
•  

  Close the pulse picker and reinsert the Be CRL

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  op.pp.close()

•  

  Move to the pinhole

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  op.pinhole()

•  

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

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  x.hex_y.tweak(0.02) x.tgx.tweak(0.02)

•  

  Save the new pinhole position

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  op.pinhole_s()

•  

  Move back to the yag

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  op.yag()

•  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)
•  

  Tweak the focus of the visar position accordingly (50 mic steps is good enough)

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  op.visar_z.tweak(0.05)

•  Turn off the VISAR trigger
•  

  Prepare the system to check the front alignment of the drive lasers

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  op.check_front_alignment()

•  

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

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  op.TTL_shutter.Toggle("openABEF") op.TTL_shutter.Toggle("closeGHIJ") x.lpl_west_x.tweak(0.05) x.lpl_west_y.tweak(0.05) op.TTL_shutter.Toggle("closeABEF") op.TTL_shutter.Toggle("openGHIJ") x.lpl_east_x.tweak(0.05) x.lpl_east_y.tweak(0.05)

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

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•  

  go to Ti sample

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  op.ti()

•  remove the Be CRL
•  

  open slit4 to 400 mic

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  op.slit4.move(0.4)

•  

  set full X-ray transmission

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  op.SiT(1)

•  

  open the pulse picker

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  op.pp.open()

•  

  Open the TCC scope

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  op.scope_timing_remote()

•  

  Set the EVR of the scope to 10Hz

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  op.lpl_check_timing("10Hz")

•  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

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  op.pp.close()

•  

  Insert the filter in front of Questar 1

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  op.fw(num=1, position=3)

•  

  Set the laser pulse shape to the timing shape

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  op.LPL.psmenu() LXX op.LPL.psefc10Hz()

•  

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

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  op.HWPon('all', set_T=1.0)

•  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

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  op.lpl_check_timing("single")

•  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

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    op.nstiming.mv(0e-9)

  •  

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

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    op.streak_window(visar=1, window=20, offset=0) op.streak_window(visar=2, window=20, offset=0)

  •  

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

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    op.ref_only( xray_trans=1, xray_num=1, shutters=False, dark=0, daq_end=True, calibrant="", rate=1, visar=True, save=True, slow_cam=False )

  •  To double check, confirm timing at another step

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    op.nstiming.mv(10e-9) op.ref_only( xray_trans=1, xray_num=1, shutters=False, dark=0, daq_end=True, calibrant="", rate=1, visar=True, save=True, slow_cam=False )

  •  Confirm with the PI that timing is all set

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

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