**X-ray delivery**

- 6 keV, ~2.8 mJ, stable delivery

**Optical laser delivery**
- ns laser for particle visualization

**Achievements/Observations**
- measured user sample for almost whole day (about 100 runs x 5 minutes)
- Julabo chiller (AGIPD) is still on target (-32 degree)

**Issues**
- MKB Ion pump error (issue fixed after resetting the device)
- NKB focus loosed. Focus reoptimized twice during the d2 shift

X-ray beam is continuously drifting in the vertical direction (XTD9_XGM)
It affects our NKB focus and focused beam is also drifting continuously.

**X-ray delivery**

- 6 keV, ~2.8 mJ, continuous beam drift in vertical direction (both XTD2 & XTD9 XGMs)

**Optical laser delivery**
- ns laser for particle visualization

**Achievements/Observations**
- measured sample for almost whole day (about 100 runs x 5 minutes)
- Julabo chiller (AGIPD) is still on target (-32 degree)

**Issues**
- Continuous beam drift in the vertical direction: NKB focus was optimized almost every 2 hours
- Sudden intensity drop in SA1 when SA2 or SA3 changes the number of pulses.

X-ray delivery

12.4 keV, ~1.4 mJ

Achievements/Observations

Beam was focused on a YaG, alignment finished up to JF4M

We had some trouble with the DAQ. It was not able to start runs properly.

We got the following error messages:

initially:

[00:01:27]: Problem of communication with data manager

[00:01:30]: Start new run ...

[00:01:38]: Failed starting data recording

DM: error at registerRun (Request to MDC timeouted)

after trying to start the run again:

[00:05:35]: Start new run ...

[00:05:35]: Failed starting data recording

DM: error at registerRun (Problem of communication with MDC

#Info: MDC-1100: MDC web server error: Error creating run

#Details: {'run_number': ['must be unique per proposal', 'has already been taken'], 'experiment_id': ['has already been taken']})

Cycling the DAQ resolved the issue.

Starting shift with mirror motor calibration:

- beam is centered on FEL imager

- pblm in XTD9 is inserted

We removed both silicon solid attenuator and pblm

Starting shift with mirror motor calibration:

- found solid attenuator 0.5mm silicon inserted

- beam is centered on FEL imager

- pblm in XTD9 is inserted

We removed both silicon solid attenuator and pblm

Dear all,

we calibrated the mirror vertical motors to their geometrically neutral.

Please be aware that saved values for beamline settings may no longer be valid. This mainly applies to the vertical motor positions, but will have an impact on Tx and Ry values as well.

As starting point, use XRO Optics Setpoints 'C' - this setting was last used to bring beam to SPB

We fine tuned geometry parameters for linear effects on X motion (parallel offset) for all three mirrors.

dTz was corrected for M2 and M3 to -6.5mm (same geometry)

dTz was corrected for M1 to +6mm

for M2 we were able to do a parabola scan Y motion to check for lrTz

lrTz was then corrected to -433mm

correction in the same direction for M3 did not yield better results

Final mirror positions at HED - see picture

Beam is now aligned back to HED for hand-over to Naresh (see picture)

points achieved:

-vibometer measurements on M2 at high energy, 2,1 and 3 mrad setting

-tried again to find beam through pblm grating, but no success

this morning, ZZ was done together with Sylvia Huynh (EEE) to solve softmono pre-mirror motor issue https://redmine.xfel.eu/issues/177392

The issue was solved and also mechanical functionality of the stage was checked.

After ZZ, the beamline remained interlocked. Hutches will be searched and closed tonight to allow final checks on Tuesday

What has happened:
During euler motion calibration of M1, we were driving the vertical motors by a few mm back and forth. At some point, the Rz motor went into error, as we attempted to go further in negative direction. Resetting the axis several times did not solve the problem. The vertical motors were then moved to 0 position. DOC was called and helped to overwrite some parameters that triggered the error.
When resuming the calibration routine, the beam suddenly got lost and the vacuum interlock triggered V0 to close. Vacuum in M1 recovered quickly, but on M2 popIn, only the direct beam could be seen. At this point, the conclusion was that one of the motor connections must have come loose, which caused the vacuum event and removed M1 from the beam.

It was then decided, that we break the interlock, vent the chamber and re-connect the motor if possible.

The situation we found was the following:
-Rz connection lead-screw to bellow was detached
-mirror sitting on the mirror holder
-significant InGa spillage on chamber bottom, window flanges opposite to the mirror AND a lot of drops on the mirror surface

Pictures are attached.

Intervention:
The lead-screw and nut were exchanged. There was significant wear on the bearing plate, connecting the lead-screw to the bellow.
When trying to install the new lead-screw with a spare bearing plate, it was found that apparently the thread on the bellow side was deformed as well, and the spare part did not fit to the thread. Since the old bearing plate was the only possible way to connect the lead-screw to the bellow, it was cleaned, lubricated and re-used. The position was manually adjusted around 0 position (66,7mm protrusion) and the motor connected.

Recommendations:
- since the damaged bearing plate was re-installed, it should be avoided to move Rz. The motor should be permanently interlocked and only operated with absolute care for initial alignment.
- the mirror surface is severely contaminated with InGa, it must be checked if a position with acceptable beam can be found (only to be done by XRO as this needs Rz to be moved)
- the affected bellow has to be exchanged to facilitate replacement of the damaged bearing plate. As this requires the mirror chamber to be opened, this only makes sense in connection with replacement of the mirror + cleaning of the chamber.

EPS issue for Transmissive imager SA1 (OTRC.2615.T9) w.r.t Operation eLog #96

The motor screen positions w.r.t. the EPS switches had been realigned (last Wednesday 8th May), tested today (14th May) and the EPS is again enabled for the different beam modes. All is back to normal.

Concerning damage of the SA1 FEL imager, Operation-2024 eLog #206

The screen position of the YAG screen - when pressing the screen selection button - has been moved by 1 mm so that the damaged area is out of the field of view, see attached screenshots (damage visible under visible light exposure).
The screenshots show the cross-hair, i.e. its nominal beam position and the circular damaged area at its original position of the screen and the new position.

More information on the damage can be found in the damage report, entry #35:
https://docs.xfel.eu/share/page/site/xfelwp74/document-details?nodeRef=workspace://SpacesStore/fd862f30-c6a3-4a5e-9a65-817cbcebb2d9
Also, there is a comment in ttfinfo: https://ttfinfo.desy.de/XFELelog/show.jsp?dir=/2024/47&pos=2024-11-19T09:39:31

840 pulses not possible at SXP due to big brother settings for the EPS Power Limit rule. The minimum pulse energy was assumed to be 6 mJ while the actual pulse XGM reading is 550 uJ.
Solution: The minimum assuemd pulse energy had been lowered from 6 mJ to 2 mJ. This shall be reverted on Tuesday next week.

EPS Interlock change for Mode30:
the 3 HIREX Interlock conditions had been disabled

Today we have observed multiple large disturbances to beam stability. These can be characterised by large jumps in the horizontal beam position, which at its extreme amounts to a loss of beam from our behalf. M2 mirror feedbacks are able to return the beam to the initial position after ca. 10 minutes. Beam jumps have been approximately 1hr apart. We do not observe the beam on the XTD6 tunnel imager in this case, but do observe good lasing quality on the XGM.

X-ray delivery

• 12.72 keV, 10Hz, ~1.4 mJ/pulse, some beam drift in the horizontal direction observed (probably mirror related)

Optical laser delivery

• 487 nm ns laser for pump-probe
• 800 nm PP laser for jet illumination, stable delivery

Achievements/Observations

• Collected PP (pump-probe) dataset with 5 us time delay more than 12 hours
• Jet and data collection was stable most of the time