Is there an issue? Escalation Path
Program
- align the beamline with no CRL from source to Zyla, including the 45° yag at TCC
- set and log all references in the preset file here
- Timing
- At TCC
- Fine timing
- close the iris to fully illuminate the imaging system for the spot size while the GAIA is timed out and the EL is OUT
- move to the 45° Yag crystal extending from the pillar
- send the optical laser then send the X-rays at full beam
- timing should be within 20 ps, so changing the VITARA timing by 1 ns should allow us to see the image turn black. Closing the slits to 400 mic for the X-rays help see the localized change of indesx of reflaction
- once you see a darkening, follow the procedure below to get timed
- go back half the last step you just did (let's assume you are going negative on the vitara)
- if you see no darkening, it means you passed t0 and you can go back positive again half the step size you did just before
- if you see drkening, you didn't go far enough, so keep going negative until the darkening disappear
- once the timing is done within 100 fs, close the slits to 50 mic and confirm spatial overlap with the pin at TCC
- record positions of the VITARA for t0 and positions of the varioous targets to be able to go back quickly to this configuration and check timing
- with the TSO imaging and the 45° YAG extending from the pillar,
- Fine timing
- At the time tool
- Fine timing
- Temporal calibration
- make sure the Si 10 mic fothick foil is inserted (still) in the beamline
- open the slits 2 to 0.4 mm
- set a cross on the edges in the spatial direction, and save a run (spatial calib)
- open the slits 2 to 0.1 mm
- set a cross on the edges in the spatial direction, and save a run (spatial calib)
- extract the mic/px value from this calibration (it is correct in both space and time axis since the objective looks at the yag/Si normal to its surface)
- open the slits 2 to 2 mm
- move the delay stage of the timetool by 149.8 mic (1ps in time) from t0 and save a 1000 events at that position with both X-rays and SPL
- save a white field at that position
- move the delay stage of the timetool by -149.8 mic (-1ps in time) from t0 and save a 1000 events at that position with both X-rays and SPL
- save a white field at that position
- move the delay stage of the timetool by 0 mic (0ps in time) from t0 and save a 1000 events at that position with both X-rays and SPL
- save a white field at that position
- Temporal calibration
- Fine timing
- Timing could check with the prefocusing lenses
- At TCC
- MXI alignment at 9.5 keV
- confirm the alignment of the pins at about 0 mm position on X of the MXI hexapod
- start alignment with x2 on the Zyla objective
set full energy beam without prefocusing lenses in to start with
op.SiT(1)
- move +14mm relative to this position to get to the 25 x 50 mic stack for 9.5 keV
- if you are lucky, you might see light through the MXI
- if yes, start aligning the lenses with the 'fish eye' method: intentionally move V to create a symmetric pattern on the image and align tip, then intentionally move U to create a symmetric pattern on the image and align tilt
- once both axis are symmetric, close the slits to 50 mic and translate X and Y to center the image on the original beam position when the MXI was out
- keep iterating until the feature is round
- record positions of the hexapods at this Z value in the preset to be able to come back when necessary
- save this position on the first preset of the virtual motor
- align the virtual motor by moving Z 10 cm away and realigning the MXI following the steps above
- once done, save the position on the second preset of the virtual motor
- confirm alignment by moving 10 cm away in Z using the virtual motor only
- save 1000 images of the beam going through the MXI and no target at TCC
- confirm the XRT spectrometer is in
- insert a Siemens star at TCC
reduce intensity to 1%
op.SiT(0.1)
or 10% if you see nothing
- confirm you image the siemens star pattern correctly
- play with the focus of the MXI until the image is the sharpest
- update the virtual motor
- save runs of 1000 images (could be 10 x 100)
- you might try to image other samples
- try the targets produced at Stanford and experience alignment procedure
- Plans for shots on target
- Obtain Talbot with the Siemens star
- Shots on target
- start with e- spectrometer friendly targets to confirm we have a trace there (last pillar)
- then move to regular pillars
- perform Talbot at late delays
- scan in MXI focusing at fixed timing and energy
- scan in time at full energy
- scan in intensity (energy) at fixed timing
Be CRL parameters
- XRT sets
- Set 1 (1500 mic)
- @ 9.5 keV, FWHM at MXI lens is 500 mic
- @ 11 keV, FWHM at MXI lens is 571 mic
- Set 2 (2x1000 mic = 500 mic??) -not used
- @ 9.5 keV, 62 m : too short focal length so not used
- @ 11 keV, 88 m : too small beam so not use
- Set 3 (1000 mic)
- @ 9.5 keV, FWHM at MXI lens is 340 mic
- @ 11 keV, FWHM at MXI lens is 460 mic
- Set 1 (1500 mic)
- Hutch sets
- Set 1 (2x100 + 1x200 mic) + 400mic pinhole
- @ 17 keV, FWHM at MXI lens is 374 mic
- Set 2 (6x300 mic) : 800 mic pinhole
- @ 9.5 keV, FWHM at MXI lens is 286 mic
- @ 11 keV, FWHM at MXI lens is 416 mic
- Set 3 (5x300 mic) : 800 mic pinhole
- @ 9.5 keV, FWHM at MXI lens is 371 mic
- @ 11 keV, FWHM at MXI lens is 480 mic
- Set 1 (2x100 + 1x200 mic) + 400mic pinhole
- MXI sets
- Set 1 (50 x 50 mic)
- @ 9.5 keV, f = 1.323e-01 m
- magnification: 4.5/0.132 ~ 34
- @ 11 keV, f = 1.774e-01 m
- magnification: 4.5/0.177 ~ 25
- @ 9.5 keV, f = 1.323e-01 m
- Set 3 (25 x 50 mic)
- @ 9.5 keV, f = 2.646e-01 m
- magnification: 4.5/0.264 ~ 17
- @ 9.5 keV, f = 2.646e-01 m
- Set 1 (50 x 50 mic)
- Viable combinations
- XRT sets
Alignment procedure
- 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
op.rs()
insert yag3 to provide a photon terminator before TCC prior to send any beam in the hutch
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
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
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
op.yag1.insert()
remove YAG0
op.yag0.remove()
remove all Si attenuators (send full energy beam)
op.SiT(1)
open the pulse picker
op.pp.open()
- fine tune the pitch of MR1L4 to center the beam on YAG1
insert YAG3
op.yag3.insert()
- remove hutch Be CRL (Mechome > Beamline > Beamline CRL(hutch))
open slit 2
op.slit2.move(5)
remove YAG1
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 authorization document for Be CRL log
---------- not for SPL ---------
- once they are done tuning
- timing check
- turn off laser triggers
go to the titanium foil:
op.ti()
- move hutch CRL out
set slit4 to 400 mic:
op.slit4.move(0.4)
send full beam on titanium:
op.SiT(1)
set the EVR to 10 Hz settings:
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
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
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:
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
- timing check