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Info
  • Excel spreadsheet for the FEL settings is here.
  • Common trajectory latest values for the X-ray mirrors are here.


Info
titleIs there an issue? Escalation Path
  • Issue concerns X-ray beam delivery: see here
  • Issue concerns ECS: see here
  •  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

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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

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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:

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        op.slit4.move(0.4)
      •  

        send full beam on titanium: 

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        op.SiT(1)
      •  

        set the EVR to 10 Hz settings: 

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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

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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 

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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: 

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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

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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

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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 

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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