1. In-air alignment:

    1. Align everything to DG1 slits
      1. Slits, lens - X and Y
        1. KB1 us and ds slits, DG2 slits - DG2 YAG
        2. DSB slits and the piezo roller blades - SC3 YAG
      2. In-coupling mirror - X, Y and clocking - IP YAG
        1. X and Y to get the beam through
        2. Clocking to make the beam rounder (not football shape, but more egg shape, it’s never perfectly round)
          1. When the yaw of the picomotor is too off, the beam also looks very football like, so we should pay attention to that besides the clocking
    2. Overlap the laser with X-ray on IP YAG
      1. Park the laser closest next to the hole to ensure the smallest angle.
      2. If the picomotor of the in-coupling mirror moves a lot to overlap, the in-coupling mirror’s X and Y need to be recentered to X-ray

  2. Find t0 at IP (in air) and timetool:

    1. Pre-focus lens in (S5 stopper in when moving lens)
    2. Find t0 at IP
      1. Find coarse timing at IP using the diode with a copper foil (should directly connect the diode to the scope, do not use chamber feedthrough)
        1. Channel 3: Blue trace, IP Diode, Input A (upper), the pump laser signal at IP position for the rough timing
      2. Find fine timing at IP using the solid targets and Acqiris (or Alvium camera). Timing targets’ performance so far: CaF2 > LuAG > YAG. 
      3. Adjust the Vitari electronic timing for it: lxt.mvr()
    3. Find t0 at TT
      1. Find coarse timing at TT using the diode
        1. Channel 4: Green trace, ATM Timing Diode, Input A (upper), the white light signal at the timetool position for the rough timing
      2. Find fine timing at TT using white light and clear YAG
      3. Adjust the TXT motor for it: txt.mvr()
    4. Scan lxt when we see both t0 at IP and TT to:
      1. Calibrate the pixel to fs for the timetool
      2. Find how much the exact t0 difference is between the IP and TT
    5. (Optional) Scan lxt_ttc to measure the instrument response function, with the timetool’s jitter correction
    6. Once t0 found at both IP and TT positions, set lxt and txt to 0 using lxt_ttc.set_current_position(0)

  3. In-air (rough) align gas cell and pinhole: 

    1. With unfocused (pre-focus lens in) beam - at 1E-5/1E-4 attenuation (1.5mJ x-rays), get the beam through JF4M detector, check the beam on SC3 YAG
    2. Get gas cell hole shadow through to SC3 - will not damage with attenuated unfocused beam
    3. Align gas cell hole to DG1 slits - X and Y
    4. Align gas cell plane - pitch and yaw, using the “moon” shadow
    5. May need to adjust X and Y again if pitch and yaw were very off
    6. Align pinhole to DG1 slits - X and Y
    7. DG2 lenses at IP

  4. In-air laser out-coupling: 

    1. Align the laser through the pinhole and gas cell
    2. Move JF4M motor z to bring the detector to the data taking position, hopefully the laser can also be coupled out at SC3 at this point
    3. NOTE: Adjusting the incoupling mirror’s tilt and yaw will also change the hole position a bit. We need to check the X-ray through the hole every time we do big adjustments on the mirror tilt and yaw and iterate. 
    4. Check/optimize spatial overlap of X-ray and laser at IP YAG 
    5. Check the laser through the pinhole and gas cell again
      1. Use the outcoupling diode, set reference with only gas cell (pinhole out)
      2. Move pinhole in and see if the Acqiris amplitude changes any
    6. We may need to iterate step d and e

  5. Pump down

    1. Before pumping down, we need to check and make sure:
      1. JF4M at data taking position (when gascell_z = 0.5, we decided to park JF4M a little far to avoid moving it in vacuum)
      2. Picomotor for the incoupling holey mirror works by looking at the pointing at the IP YAG
      3. Piezo slits (one blade is not moving, we are not using them for 9.8keV now)
    2. Follow the CXI SC1-DSC COMBINED PUMP DOWN AND VENT PROCEDURES-rev-2
    3. Do not accidentally vent through the roughing line “C”

  6. In-vacuum (fine) align gas cell and pinhole:

    1. With unfocused beam (pre-focus lens in), looking at the SC3 YAG
    2. Check/align gas cell to DG1 slits
    3. Check/align pinhole to DG1 slits

  7. DG2 lens in (S5 stopper in when moving lens)

  8. Close slits

    1. Slits to 0.3mm (DG1-DG2, tapering from 0.5mm to 0.3mm) - DG2 YAG
    2. Close DSB slits to ~0.07, 0.08mm - SC3 YAG
    3. SC1 roller blades tight ~50um - SC3 YAG

  9. In-vacuum (fine) align gas cell and pinhole by minimizing the JF4M background scattering

  10. In-vacuum (fine) align the laser

    1. Check/optimize spatial overlap of X-ray and laser at IP YAG, now the X-ray is focused (much smaller), use low intensity (~1e-5 transmission)
    2. Check the laser through the pinhole and gas cell again
      1. Use the outcoupling diode, set reference with only gas cell (pinhole out)
      2. Move pinhole in and see if the Acqiris amplitude changes any
    3. We may need to iterate step a and b using IP YAG and the Acqiris amplitude
      1. Use the pinhole and Acqiris to determine which direction and how much it is off (usually <50um)
      2. Use SmarAct to move one direction on the IP YAG, making laser off X-ray markers (usually a few beam sizes)
      3. Use the picomotor (holey mirror) to bring laser back to the markers
      4. Check it makes outcoupling better or worse 
      5. 7 clicks with SmarAct and bring back with picomotor moves laser on pinhole ~20um

  11. Data taking mode

    1. Monitor the Acqiris amplitude for the incoupling and outcoupling diodes, make references and compare the real-time signal to the references, also make plots of the cursor integrals 
    2. If the amplitude is decreasing (and also white light on TT is decreasing) we should tweak the compressor
    3. Monitor the the TT edge: should be centered around 500 pixels
      1. Use lxt to bring it back if too off
    4. Monitor the pump-probe signal with shared memory and offline data
      1. If it is very low, check the spatial overlap on the IP YAG

  12. Following shifts

    1. Once things are already aligned, we should only do minimum touch, we should use DG1 YAG, DG2 YAG, IP YAG, SC3 and markers as the reference to bring the X-ray trajectory back. 
    2. If the vacuum background is good with full X-ray intensity, we should take it and not touch any motor alignment any more.
    3. Tweak up the laser compression by looking at the UV pulse energy and white light on TT, align it on IP YAG and check the outcoupling on Acqiris diode
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