achievements:

• FEL beam realignment because pointing was off since we had 0 pulses during the night
• coarse timing was found
• knife edge scans of FEL to achieve twice the PPL beam size

problems:

• several machine interruptions, partially due to corss-talk with sa2 and 4.5 MHz oparation
• gate valve before KB XOX/GV3 goes into interlock and then stays closed, probably due to pressure spikes

achievements

• aligned the beam through up to the XOX imager
• prepared FFT for reflectivity measurement
• tested new DSSC gain files for Tb M5 edge

problems

• in-vacuum piezo motor for the THz parabola stopped working, venting XOX required for troubleshooting, not using the X-ray beam this night

SA2 photon beamline

- SRA position were 7 mm x 7 mm, MID reported they see the hallow of beam shadow at MID Popin

- I have closed the SRA to 3.5 mm x 3.5 mm

- SA2 photon beamline

Today morning found the CRL1: 5 and 6 arm and Pop-in 45-I are still IN. I have retracted them.

around 6:15, the lights as the one shown in the attachment turned on by themselves in the control hutch. after some minutes, they switched off.

from the exp hutch camera, we realized that this happened in there as well, which impacted negatively on the running measurement. The pnCCD is sensitive to ambient light and we have to keep the hutch dark while measuring.

Why did these lights turn on?

X-ray delivery

• 12.2-12.45 keV, up to 339 pulses at 1.13 MHz, 0.8-1.2 mJ.
• Couple of minutes beam interruption.

Optical laser delivery

• NA

Achievements/Observations

• Calibration of XPD's CAL/LPM at 12.4 keV.
• Measurement of CRLs transmission with LPM.
• Realignment of CRL chamber and all arms.
• Realignment of IRDa components and focus optimisation. Optimal focus with 17 lenses at 12.38 keV.
• Installation of remaining IRDa components: side microscope and flight tube.
• References taken in both IRDa's microscopes for laser setup next week.

Issues

• None.

beam parameters: 20 keV, 300 uJ, 352 pulses

• continuation of user programe.
• Machine performance very good for trying the 20 keV the first time. Experiment also going well.

X-ray delivery

• 10.65 keV, up to 339 pulses at 1.13 MHz, 1.6-1.8 mJ.
• 12.4 keV, up to 30 pulses at 1.13 MHz, 1.0-1.2 mJ.
• Beam not aligned to the crosshair at 12.4 keV, but we could work with it as it is to avoid further tuning.
• Overall stable delivery.

Optical laser delivery

• NA

Achievements/Observations

• Thermal measurements with Be and Al CRLs under various conditions.
• Performed test with SQS to determine the effect changing number of SASE1 bunches. Upon changing from 339 to 30 bunches at 1.13 MHz, the pump-probe signal in SQS decreased by ~30% and partially recovered within a few minutes, but was at not point lost. Clearly, the decision made yesterday that prevented us to use the beam over the last two hours of the shift and to complete our programme was not based on solid evidence.
• Setup and alignment of IRDa in preparation for next week.

Issues

• Photon energy was changed from 12.4 to 12.0 keV shortly after 23:00 while we were still using the beam.

03 Jun 2023, 13:46

We called the BKR to ask what they can do about our pulse energy being 50% (~160uJ and slowly dropping) of what it was since we made our hutch intervention (with 0 bunches). BKR were asked to organise a time slot with PRC and the other instruments to make an intervention to try to increase our pulse energy.

We have one cell (CH4) which is low-Z and would require higher pulse energies for x-ray heating. We are flexible as to when this intervention happens this afternoon as in the meantime we can continue to work with other cells.

X-ray parameters: 20 keV,  352 pulses, ca 300 uJ

• running user samples.

experiment going overall well.

X-ray performance:

• Good - still crosstalk issues with SA3 so we have to call BKR everytime we change bunches to 30 (alignment mode), or 0 (hutch intervention).

AGIPD took damage to one module yesterday (top left) leading to a short in the high-voltage line but is still performing well with only 7/8 modules. We will investigate what the extent of the damage is after the experiment.

X-ray delivery

• 10.65 keV, 128 pulses at 1.13 MHz, 1.6-1.7 mJ.
• Overall stable delivery.

Optical laser delivery

• 800 nm, 50 fs, 226 pulses at 1.13 MHz.

Achievements/Observations

• Continued characterisation of crystals (thermal measurement, interferometry, imaging) under different beam conditions ranging from direct to focused beam.
• Spectral measurement in parallel to crystals characterisation.
• Imaging of static samples with Zyla and Shimadzu.

Issues

• We were not able to complete the last part of our programme since we were not allowed to change the number of bunches and repetition rate. Measurement ended at 21:00 and last two hours fo the shift were spent in discussion with SQS/BKR/RC/PRC with no positive outcome.

we lost spatial overlap on several instances.

It seems that this happens when SASE2 changes number of pulses.

when we have SASE2 changing number of pulses, spatial overlap is lost and this goes with a change in the position read by the xgm in the order of ~20um (e.g. attachment 1).

Yet, the XGM position reading is not really representative of the effective pointing changes: a drift of that order, occurring when there is no change in SASE2, does *NOT* correspond to a loss in the overlap (seen in the N2 signal in our experiment).

in summary: some evidence suggests that SASE2 number of pulses changing affects our FEL beam pointing. Yet, we don't have a diagnostics allowing us to quantify this.

X-ray delivery

• 10.65 keV, 128 pulses at 1.13 MHz and 16 pusles at 141 kHz.
• Overall stable delivery.

Optical laser delivery

• 800 nm, 50 fs, 1-226 pulses at 1.13 MHz.
• A few issues with minor impact on operation this week. Detail communicated to LAS.

Achievements/Observations

• Continued characterisation of crystals (thermal measurement, interferometry, imaging) under different beam conditions ranging from direct to focused beam.
• Spectral measurement in parallel to crystals characterisation.
• Imaging of static samples with Bragg magnifier.

Issues

• DAQ configuration failing multiple times. Repeating the same sequence of actions yield variable results.
  • Several times with unhelpful message "Failed to execute "assign" action".
  • On one occasion with the message "Assignment for data-source/group 'SPB_CFEL_JF1M/DET/JNGFR09:daqOutput'/'SPB_CFEL_JF1M_9' not specified." even though we used this group before without any issues.
• JUNGFRAU 1M acquisition could not be stopped. Restarting control and receiver servers and associated devices resulted in the control device being stuck in INIT state. Detector had to be power cycled to solved the issue.

X-ray parameters: 20 keV (20080 eV from HIREX), 352 pulses, cca 250 uJ

• changed setup to diamond anvil cell experiments with laser heating
• installation of AGIPD detector
• running user samples, mostly carbon materials to constrain the phase diagram of carbon at high pressures and temperatures.

experiment going overall well.

X-ray performance:

• train with increasing tendency  of X-ray pulse energies but we found a workaround. X-ray heating still working to some extend even on carbon
• mirror feedbacks on and working
• CRL3 focus to below 10 um

AGIPD detector OK

X-ray delivery

• 10.65 keV, 128 pulses at 1.13 MHz and 16 pusles at 141 kHz.
• Slope reduced at the start of the shift. Approximately 20% slope after that with the patterns used for data collection today.

Optical laser delivery

• NA

Achievements/Observations

• Spectrometer setup and aligned. Collected first data with GOTTHARD II.
• Measured multiple static samples with Bragg magnifier.

Issues

• No issues.

HED reported that they are unable to go 352 pulses and while changing/dailing the no. of pulses in the bunch Pattern it is showing the EPS is limited to 300 pulses. It seems on the SA2_MAIN scene the link for bunch Pattern apparently using the macros scene, which is preventing it from going to 352 pulses. Now I have updated the link with a new scene of MDL for the bunch pattern. In the attachment, you will find both scenes. One toward the left is MDL bunchPattern configurator and one towards the right is Macros bunchPattern. 

Now the issue is solved. 

thanks

Naresh

PRC wk 22

X-ray delivery

• 10.7 keV, up to 339 pulses at 1.1 MHz.
• Large slope through the train, up to 70% with 339 bunches. BKR was not able to find the cause so far, we agreed to pursue this further tomorrow.

Achievements/Observations

• Timing optimisation of FLIR camera.
• Heating measurement of Al and Be CRLs with FLIR camera and thermocouples.

User proposal 3273:

• X-ray delivary
  • We use several deliveraly modes:
    • Continous single pulse
    • Continous 30 pulses
    • POD: 1 pulses / 30 pulses
  • All works fine, FXE is sastificed with X-ray delivery
• DA:
  • Few minor issues with offline calibration, DOC helped to solve it
  • Error with LPD. Solve remotlyh thanls to Hazem

In general very good perfomances

we were trying to make THz and cross correlate this to the pump laser.

We managed to see THz and an auto-correlation with the pump laser therein. Unfortunately we did not see any THz generation using the FEL.

Problems:

Many. Only one problem was related to the FEL: weirdly, the zeroth order of the monochromator beam was much weaker than the first order, which is worrysome.

X-ray delivery

• 10.7 keV, 1.2 mJ, 1-200 pulses, stable delivery

Optical laser delivery

• None

Achievements/Observations

• Crystal alignment for X-ray microscopy except one crystal
• Sample camera and Cu mesh were aligned to X-ray position

Issues

• We found strange strip on the beam in XTD0 screen