our pp laser experienced timing jumps by 18 ns today. this happened for the first time at ~7:30 in the morning without us noticing and a couple of more times during the morning. we realized it at 15:30 due to the fact that the signal on our pulse arrival monitor (X-ray/laser cross correlator downstream of the experiment) disappeared. we spent some time to investigate it, until we also see this jump in two different photodiodes different triggers (oscilloscope and digitizer) so it was clear that it is indeed the laser timing jumping. we also see the laser spectrum and intensity change for the trains that are offset in timing.

we called laser OCD at ~16:30. they have been trying to fix the problem by readjusting the instability zone multiple times and by adjusting the pockels cell, but this did not change the timing jumps. at 21:30 they concluded that there was nothing more they could do tonight and a meeting should happen in the morning to discuss how one can proceed.

effectively, this means that we lost the entire late and night shifts today for the pump-probe beamtime and have some data of questionable quality from the early shift as well.

Today in the afternoon, SASE1 was tuned (a description of the activities in att 4). We now realize that this has in some form changed the SQS pulse parameters.

att 1 shows ion spectra recorded under nominally the same photon parameters before (run 177) and after (run 247)

it's also visible in the history of the SASE viewer that the behavior of the SASE3 pulse energy is different before and after 15:45, which is right when SASE1 was tuned. it clearly started fluctuating more. however, we don't think that the pulse energy fluctuations themselves are the reason for the large change in our data, we rather suspect a change in the pulse duration and/or the source point to cause this. however, we have no means to characterize this now after the fact.

it is particularly unfortunate that the tuning happened exactly BEFORE we started recording a set of reference spectra on the SASE3 spectrometer, which were supposed to serve as a calibration for the spectral corelation analysis to determine the group duration, as well as for a training data set to use the PES with machine learning as a virtual spectrometer for the large data set taken in the shifts before.

Dear all,

Due to a probable issue at the SA1 Transmissive imager, the "OUT" and "YAG" position indication signals seems to be not responsive.

After the FXE team noticed that MODE S was interlocked, the root cause has been narrowed down to this component. Later, further investigation with A. Koch & J. Gruenert (XPD) has confirmed this fact. Apparently to recabling works performed during yesterday's ZZ may have something to do with this issue.

Once that the complete retraction of all the screen has been jointly confirmed via DOOCS and Karabo, the affected interlock condition (see attached picture) has been disabled for the rest of the week to allow normal operation of SA1 (release of MODE S and MODE M).

Further investigation and the eventual issue resolution is expected to happen on Tuesday next week via ZZ-access.

With best regards,

Raul [PRC@CW19]

Issue with SA3 Gas attenuator (SA3_XTD10_GATT) - SOLVED

Dear all,

after the reported issue by SQS colleagues regarding the impossibility to inject Argon, and after a first remote evaluation, we (VAC) have entered XTD10 to assess the status and verify the most probable working hypothesis: a manual valve in the supply line was closed (otherwise as expected). Joshua and Benoit confirmed it and the showstopper is now gone. The system is back to normal and standard operation can be resumed in any moment. 

A small remark: as Argon (or any other gas different from Nitrogen) is not the default operation mode, it is important that if needed, there should be an explicit request during the preparation of the operation tables with XO. This would help to avoid this kind of situations. Unfortunately sending a short notice e-mail just before the next run is clearly not recommended.

With best regards.

X-ray delivery
- 9.3 keV, >3 mJ/pulse, stable delivery 

Optical laser delivery
- 800nm PP laser for jet illumination, stable delivery

Achievements/Observations
- Optimised hexapod position for SFX
- Collected granulovirus data for geometry calibration
- Started user sample delivery but clogged the nozzle a few times

X-ray delivery
- 9.3 keV, >3 mJ/pulse, beam down around 30min

Optical laser delivery
- 800nm PP laser for jet illumination, stable delivery

Achievements/Observations
- Collected a lot of data (from midnight to 6am) with different sample concentrations and mixing delays with the users

In-house/commissioning beam time summary night 1

X-ray delivery:
12.7 keV, up to 208 pulses at 1.1MHz, 1.1-1.5 mJ

Optical laser delivery:
PP laser for illumination

Achievements/observations:
Minimised air scattering background on Jungfrau
Collected serial crystallography data with 8, 10 and 13 pulses per memory cell and good hit rates

Issues:
Sample growing again from the catcher cone

In-house/commissioning beam time summary night 2

X-ray delivery:
12.7 keV, up to 288 pulses at 1.1MHz, ~1.2 mJ

Optical laser delivery:
PP laser for illumination

Achievements/observations:
Collected a lot of data: continued 8 pulses per memory cell, around 1h30-2h 1 pulse and 3 runs with 18 pulses.
 

Staff: MS, RB, PS, RdW

In-house/commissioning beam time summary night 3

X-ray delivery:
12.7 keV, up to 288 pulses at 1.1MHz, ~1.3 mJ

Optical laser delivery:
PP laser for illumination

Achievements/observations:
Collected a lot of data with Jungfrau, burst mode 16 memory cells: 
- 1, 4 and 18 pulses/memory cell 
- one run of each setting 1, 4, 8, 10, 13 and 18 pulses/memory cell one after the other
- 8 pulses with 32% transmission
- 4 pulses with half the repetition rate (0.5MHz)

In-house/commissioning beam time summary night 4

X-ray delivery:
12.7 keV, up to 128 pulses at 0.5MHz, ~1.3 mJ, one very short beam down.

Optical laser delivery:
PP laser for illumination

Achievements/observations:
AGIPD timing scan, fine and coarse
A few runs with Jungfrau

Issues:
Some sample delivery issues
Some Jungfrau pipeline issues (will be investigated by DOC during the day)

End of User beamtime 5157

X-ray delivery

11.56 keV 202 pulses @0.5 MHz, ~1.0 mJ

some downtime due to fire alarm in the tunnel

Optical laser delivery

800 ns laser for jet visualization

PPLaser for time-resolved data collection

Achievements/Observations

• PPLaser timing and alingment done
• Collected several hours of PYP sample with 30ps laser delay

Issues

• DAMNIT issue solved with OCD DA
• some online calibration issues from before persisted

X-ray delivery

12.40 - 12.82 keV, ~1.1 mJ

Optical laser delivery

800 ns laser for jet visualization

Achievements/Observations

• 800 ns laser for jet visualization (aligned but not timed)
• Jungfrau timing done
• IRDa focus done
• IRDa fully aligned
• Sample delivery ready
• Powder data collected

X-ray delivery

12.40 - 12.82 keV, ~1.1 mJ

Optical laser delivery

ns laser for jet visualization
ns laser for pumping ready but not used

Achievements/Observations

• Focus IRD
• ns time and spatial overlap
• Collected lyzo data
• Collected dark rhodopsin data
• New opaque foil installed on cube X-ray exit side

Issues

• Roadrunner motor issues solved after manual intervention and computer restart

X-ray delivery
8.951 keV, 1.2 mJ up to 30pulses at 113 kHz

Achievements/Observations
Beam trajectory at 8.951 keV
IRDa slits left/right blades connected
Sweeped pulses could be observed on fluorescent paper in front of the Downstream screen
Mirror synchronisation parameters could be found
Jungfrau halves were closed and the downstream cone installed
Background was minimised using the IRDa slits

X-ray delivery
8.951 keV, 1.6 mJ up to 16 pulses at 113 kHz

Achievements/Observations
More than 1h of beam sweeping with lysozyme crystals
Several runs of vitamin C beam sweeping data

Issues:
Several synchronization methods were tested for the mirrors but without improving it
 

X-ray delivery

12.5 keV, ~1.6 mJ

Achievements/Observations:
Collected almost 40 runs of the priority sample with 7 pulses per train using the Polypico injection system.

Issues:
Jungfrau controller issue when changing back to single cell adaptive to collect powder data with new geometry (solved together with DOC).
Pipeline issue after requesting single cell correction - still the same bug in the calibration pipeline, the pipeline has to be re-instantiated after the change.