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1. Install a fast diode and mirror (roughly at 45 degrees with respect to the beam) on the SC1 sample_x stage
2. Roughly align the fast diode and mirror using the reference laser at the time tool (-4 mm in position but this will soon be changed to 0 mm.   If the "out" position is 92 mm, then -4 mm, if 96 mm, then 0 mm).
3. Insert a nozzle rod with both a clear YAG and a frosted YAG. 
   1. At CXI, the clear YAGs are typically thinner, around 20 um, whereas the frosted YAGs are thicker, around 50 um
4. Determine the position of the X-ray spot at the IP using the clear YAG and the beam with 1x10-4 Transmission
   
   1. (zoomed in view)
      
5. Align the laser with crosshairs on the inline cameras that represent the location of the X-ray beam
   1. In the image below, the bright spot is the laser spot at the interaction point (IP) visualized using a frosted YAG.  The frosted YAG is on the upper half of the image.  There is a small gap followed by the bottom 1/4 of the image having a clear YAG.
   
   1. The laser needs to be repointed using Pico X (CXI:LAS:PIC:03) and Pico Y (CXI:LAS:PIC:02). These PVs can be changed and chich which of the the tow motors does pitch and yaw can change so these are not set in stone.
6. When the laser is roughly centered on the X-ray spot (the laser should be on the order of 100-150 um), the X-ray beam needs to be made similar in size at the interaction point to the laser.  In order to do this at CXI, insert Be lenses at the DG2 location to focus the beam upstream of SC1 and produce a larger, divergent beam at the IP.
   1. The DG2 lens screen is found in the DG2 section of CXI home
      
7. The Be lenses will need to be aligned in both x and y using the DG2 PIM and then the DG2 slits will need to be closed to stop any intensity outside the Be lenses aperture
   
   1. Beam on DG2 without lenses
      
   2. Beam on DG2 with lenses but without slits aligned
      
   3. Beam on DG2 with lenses and with DG2 slits aligned
      
   4. The DG2 slits need to be closed such that there is no beam intensity outside the lens aperture.  If intensity remains outside of the lens aperture it will be focused to the 1.3 um spot size in the IP and damage the YAG at full intensity
8. Open all gate valves and remove objects upstream of SC1 before bringing the beam to the IP. 
   
   1. Since the beam is being refocused upstream of SC1 to make the larger beam, we could inadvertently place the focused beam on upstream diamond windows or other objects and damage them
9. Look at the beam on the clear YAG in SC1
   1. The beam should be similar in size to the laser beam or the signal used for timing in SC1 will be low
      
   2. (zoomed in view)
      
      
   3. Optional: Use the large beam at SC1 to align the DSB slits, SC1 jaws, and SC1 ap0 and ap1 motors to be roughly centered.  it is easy
10. For the timing scan you will need 100% transmission in the sample chamber
11. For the timing scan we (as of 22-Oct-2018) are using a timing scan in iCXI( a hutch python instance)
12. Load icxi by typing "icxi" in any terminal on the cxi machines (cxi-daq, cxi-monitor, etc.)
13. Load the time scan by typing "%timescans" into the ipython terminal
    
14. The laser signal should be on the acqiris.  In the case of LS87 we were using channel 1 to look at the diode outside SC1 and we should strive for a peak height of ~1V to ensure that the cross correlation signal is strong
    
15. For time scan, type "ts.scan_times(start_delay, end_delay, step_size, nevents_per_timestep=360, randomize=True)" in the icxi terminal
    
16. Before running the scan, a plot needs to be set up that plots the integrated laser intensity on the acqiris vs the laser ns Target Time (LAS:FS5:VIT:FS_TGT_TIME_DIAL)
    Image Added
    1. Set cursors both earlier and later than the laser peak on the acqiris and in "Expr" under Expression manually add "a integral b" using the integral sign
    2. Plot A integral b as a function of LAS:FS5:VIT:FS_TGT_TIME_DIAL and choose the hi and low values consistent with the scan.  The above example shows the typical final low and hi values chosen when we are very close to t0
17. The time scan, if done properly, will produce a plot that looks similar to the one below
    Image Added
    
    1. The current convention used at CXI is that the first dip in the integrated intensity is used as t0 (not the inflection point).  In the example from LS87 above, a t0 value of -400 fs would be a reasonable number.
18. The t0 value would be updated in the laser timing screen
    Image Added
    1. The ns Target Time should be set to -400 fs to determine the value of the final timing number (LAS:FS5:VIT:FS_TGT_TIME, in the above image it is 4392.074100).
    2. The ns Offset should be changed to be the value of LAS:FS5:VIT:FS_TGT_TIME.  Once this change is made the ns Target Time should reset to 0.000000.
19. Once timing has been established in SC1, timing must be found at the time tool.  If the time tool delay stage position is roughly known, then timing at the time tool is relatively easy and you can skip to step YYY.

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