9.4.2.0 Spatio-temporal alignment procedure

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Is there an issue? Escalation Path

Issue concerns X-ray beam delivery: see here
Issue concerns ECS: see here

Initial Spatial overlap between LPL, VISAR and X-rays

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
```
op.yag()
```
Remove the hutch Be CRL
Close slits 4 to 50 mic
```
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
```
op.pp.close()
```
Move to the pinhole
```
op.pinhole()
```
Tweak the position of the pinhole until it is centered on the cross
```
x.hex_y.tweak(0.02)
x.tgx.tweak(0.02)
```
Save the new pinhole position
```
op.pinhole_s()
```
Move back to the yag
```
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)
```
op.visar_z.tweak(0.05)
```
Turn off the VISAR trigger
Prepare the system to check the front alignment of the drive lasers
```
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

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

Initial Temporal overlap between LPL and X-rays

go to Ti sample
```
op.ti()
```
remove the Be CRL
open slit4 to 400 mic
```
op.slit4.move(0.4)
```
set full X-ray transmission
```
op.SiT(1)
```
open the pulse picker
```
op.pp.open()
```
Open the TCC scope
```
op.scope_timing_remote()
```
Set the EVR of the scope to 10Hz
```
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
```
op.pp.close()
```
Insert the filter in front of Questar 1
```
op.fw(num=1, position=3)
```
Set the laser pulse shape to the timing shape
```
op.LPL.psmenu()
LXX
op.LPL.psefc10Hz()
```
Send the 10Hz LPL (enable the trigger of the ns slicer) on target at full energy
```
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
```
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
  op.nstiming.mv(0e-9)
- Confirm that the streak window have zero offset in the window size requested
  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
  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
  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 )
- Fine tune the timing is the X-ray trace is not where it is expected using the nstiming.mv function accordingly.

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

Start by moving to the desired target (refer to the python manual here for details on the arguments)
```
op.move_to_target(config="colinear", frame_cfg=[1, "F1", 1, "F2", 1, "F3"], frame=2, target="A2")
```

Continue by checking the alignment of the drive lasers
- Set the system in a mode where the laser energy is minimum, the filter is removed from questar 1 and the trigger is enabled
  op.check_front_alignment()
- Confirm you see a scattering signal close to the X-ray cross (342, 561)
- Move the hexapod X axis to center the beams on the cross and produce a round scattering signal (steps of 50 mic is good)
  x.hex_x.tweak(0.05)

Continue by checking the alignment of the VISAR system
- Adjust the VISAR Z axis to make sure the image is round and sharp (could be set to the value by using the right equation as well). Steps of 50 mic is good.
  x.visar_z.tweak(0.05)
- Alternatively, move the Z value by exactly the thickness of the ablator + material of interest and add the change in position due to the visar window. To calculate the change use the following command
  op.visar_window_compensation(material="LiF", thickness=400e-6)

Take reference images with VISAR and/or X-rays

For 5 references with VISAR and X-rays (at 20% max)

Take a driven shot with the LPL

For a driven shot at full energy (lpl_ener=1.0), with X-rays arriving 5 ns later (timing=5.0e-9) at full intensity (xray_trans=1) use the following command

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