Page History

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•  Prepare the hutch for the shift (done 1h before the actual start time)
  
  •  open the grafana dashboards located here (requires UNIX login/pwd) to access beam owner, energies and coatings
  •  no gate valve in the trajectory
    
    •  check in the vacuum windows that no gate valves from the NEH to the MEC hutch are IN (red)
    •  it is ok that the DG2 STP 1 is IN
    •  it is ok that the GL window is IN in MEC
  •  

    open the rolling status and confirm that no devices upstream the hutch obstructs the beam
    

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    op.rs()

  •  

    insert yag3 to provide a photon terminator before TCC prior to send any beam in the hutch
    

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    op.yag3.insert()

  •  confirm that the chamber is loaded with targets and being pumped down to be ready at the start of the shift
  •  search the hutch but leave SH6 IN (you are not the beam owner yet)
•  15 min before the shift begins, call ACR at x2151 to check
  •  look at current ACR beam operator on shift here
  •  confirm photon energy
  •  confirm pulse energy
  •  confirm pulse duration
  •  confirm beam mode
  •  confirm multiplexing mode
    
  •  ask for an e-loss scan
    
•  transition to beam ownership
  •  ACR calls you to confirm they are tweaking the beam for you
  •  confirm with ACR that MR1L0 and MR2L0 have the right coating following this page
    •  if moving the mirror yourself, then open MR1L0 and MR2L0 HOMS GUI located in the mechome > LCLS tab > HOMS overview button
    •  set the coatings to the appropriate material as a function fo the photon energy as per the page from above
•   getting ready to accept the beam:
  •  close DG2 STP 1
  •  make sure the reference laser is out (check in the rolling status)
  •  confirm the target chamber is pumped down
  •  insert the Be window IN the beamline
  •  search H6 if not already searched
  •  remove SH6 OUT of the beamline
•  beamline alignment
  
  •  ACR calls you to confirm beam is ready for alignment
  •  

    force close the pulse picker to make sure it does not let the beam propagate to the hutch yet

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    op.pp.close()

  •  check MR1L3 mirror OUT (-6000) position (XCS mirror)
  •  check the XPP slits (slit1) are open (20mm, 20 mm) in the rolling status
  •  open the mirror settings located here
  •  confirm bending values for MR1L0 and MR2L0 (advanced)
  •  

    insert YAG0

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    op.yag0.insert()

  •  confirm FEL beam is on the cross for the OUT position (undeflected beam)
    
  •  confirm the shape of the beam is round (advanced)
  •  set the MR1L4 coating as per this page
  •  insert MR1L4
    
  •  confirm FEL beam is on the cross for the IN position (deflected beam)
  •  

    insert YAG1

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    op.yag1.insert()

  •  

    remove YAG0

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    op.yag0.remove()

  •  

    remove all Si attenuators (send full energy beam)
    

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    op.SiT(1)

  •  

    open the pulse picker

    Code Block
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    op.pp.open()

  •  fine tune the pitch of MR1L4 to center the beam on YAG1
  •  

    insert YAG3

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    op.yag3.insert()

  •  remove hutch Be CRL (Mechome > Beamline > Beamline CRL(hutch))
    
  •  

    open slit 2

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    op.slit2.move(5)

  •  

    remove YAG1

    Code Block
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    op.yag1.remove()

  •  fine tune the pitch of MR1L4 to center the beam on YAG3
  •  to adjust the height using the YAG3 red cross centered at (265, 282), call ACR, and for a 200 mic motion on the yag, ask them to move 200/4 mic up or down.
    •  you could set SiT(0.2) to not saturate the image
    •  you could set 10 images averaged to get a cleaner picture
  •  log the mirror settings in our table here
  •  confirm photon energy and lens stack to use and log the change of stack in the paper document for Be CRL log
  •  insert the Be lenses with these parameters
    •  set 1: 9 keV, 9 x 300 mic, f = 3.96 m, Y = 2.8816 mm
    •  set 2: 17 keV, 10 x 100 mic, f = 4.4243 m, Y = 29.52 mm
    •  set 3: 22 keV, 9 x 50 mic, f = 3.904 m, Y = ?
•  once they are done tuning
  
  •  timing check
    •  turn off laser triggers
    •  

      go to the titanium foil:

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      op.ti()

    •  move hutch CRL out
    •  

      set slit4 to 400 mic:

      Code Block
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      op.slit4.move(0.4)

    •  

      send full beam on titanium: 

      Code Block
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      op.SiT(1)

    •  

      set the EVR to 10 Hz settings: 

      Code Block
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      op.lpl_check_timing(rate='10Hz')

    •  set vertical division to 10 mV/div on oscilloscope Lecroy 1
    •  once you see the signal of the X-rays, set 100 sweep to average the signal
    •  save it on memory 2
    •  set back sweeps to 1 on channel 2
    •  move target about 0.8-1 mm negative to target the Al frame
    •  turn on the LPL trigger on, event code 43 for 10Hz
    •  once you see the signal of the LPL, set 100 sweep to average the signal
    •  

      move timing to overlap the LPL with the memory trace 2 using the python command

      Code Block
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      op.nstiming.mvr(2e-9)

      to move the LPL 2 ns later than the FEL, but this is just an example! Move it (or not) by the necessary amount to overlap best the rising edges of the beams.

    •  

      save the current value as our t0, using hte python command 

      Code Block
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      op.nstiming.save_t0()

    •  once timed, set 100 sweep to average the signal and save the trace on memory 3
      
    •  take a screenshot and put it in the elog
    •  move back the hutch Be CRL
    •  set the slits back to data-taking move size
    •  

      set the EVR to single shot settings: 

      Code Block
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      op.lpl_check_timing(rate='single')

    •  set the scope Lecroy 1 channel 2 voltage/div to the maximum (1V/div) to be able to observe the shot on the diode and monitor the timing
  •  laser
    •  

      select the laser pulse shape

      Code Block
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      meclas.LPL.psmenu() L3

      to choose pulse shape : 8ns flat top, max 80J

    •  

      start by optimizing the conversion efficiency

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      meclas.LPL.SHG_opt()

    •  

      finish by optimizing the pulse shape

      Code Block
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      meclas.LPL.psefc10Hz(numIterQ=150)

  •  detector 
    •  confirm LPL event code is either 182 or 43 (precaution)
    •  

      in python, set event sequencer to 120 Hz:

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      op.x.start_seq(120)

    •  aadd the detectors you want a pedestal for, remove any VISAR or slow cameras and allocate the DAQ
    •  

      in a random DAQ terminal, execute
      

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      takepeds

      and follow instructions

    •  

      after takepeds is done, execute 

      Code Block
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      makepeds -r xxx -u yourusername -q milano

      with xxx being the run number and yourusername being the user name of the person who extract the pedestal, then follow instructions

    •  shutdown the DAQ (don't need to 'restartdaq'), reallocate and confirm the pedestal has been applied
    •  alight Ge spectrometer 
    •  check 4 Quads with calibrant sample (CeO2) for q range