X-ray delivery

• 18.8 keV, 260 uJ pulse energy

Optical laser delivery

• No optical laser

Achievements/Observations

• Experimental setup optimized, both instrumental side and PIXIE side
• X-ray beam focused to the PIXIE and transmission measurement was done with several different PIXIE operation conditions.

Issues

• No beam for ~4.5 hours due to ZZ.
• X-ray beam not found with IRDa InlineMic after focusing X-ray beam to IRDa sample plane.
• InlineMic Y motor is in error states. It has to be fixed during the day.
• upstream kapton window for the downstream vacuum pipe broken. The glue has become loose. No damage by X-ray was visible.

X-ray delivery:

20 keV,  250-400 uJ, 250 pulses, stable delivery

Optical Laser:

1030 nm, 850 fs, stable delivery

Achievements / Observations:

Lots of data collection

Issues:

No major issue today

Beam Downtime

During last night, apparently the photon beam was down in all SASE beamlines during two longer periods:

• between 2:48am and 3h23am (35 min) on 14.4.2025
• between 5:09am and 6h59am (1 hour 50 min) on 14.4.2025

Staff: PV, TS, JK, FK, + users

X-ray delivery:

20 keV, ~ 300-400 uJ, 250 pulses, stable delivery 

Optical Laser:

1030 nm, 850 fs, stable delivery

Achievements / Observations:

Lots of data collection

Issues:

No major issue today

X-ray delivery:

20 keV, ~ 500 uJ, 246 pulses, stable delivery

Optical Laser:

1030 nm, 850 fs, stable delivery

Achievements / Observations:

Lots of data collection

Issues:

Shimadzu camera for Schlieren imaging had issue with shutter, mechanically broken.

X-ray delivery:

20 keV, ~ 400 uJ, 246 pulses, stable delivery

Optical Laser:

1030 nm, 850 fs, stable delivery

Achievements / Observations:

Spatial and temporal alignment of optical laser setup
Data collection

X-ray delivery:

20 keV, ~ 400 uJ, 128 pulses, stable delivery 

Optical Laser:

1030 nm, 850 fs, stable delivery

Achievements / Observations:

Rough timing alignment of optical laser setup
Took some initial data 

Issues:

No major issue to report

X-ray delivery:

20 keV, ~ 400 uJ, 128 pulses, stable delivery 

Optical Laser:

1030 nm, 850 fs, stable delivery

Achievements / Observations:

20 keV beam to sample position and cameras
Rough alignment of optical setup
 

Issues:

Optical laser from light conversion had issue with shutter control

SASE3 Apple-X undulator cell 26 issue - SOLVED

During the night, an issue appeared with the SASE3 undulator cell 26 (2nd last Apple-X undulator).
This cell could not be operated and was in status open.
BKR therefore couldn't tune for linear vertical polarization as required by the SASE3 users at SXP.
A ZZ access was discussed and prepared with the experts from the undulator group.

However, they now found a way to repair the issue from remote without access (info from Mikhail Yakopov / undulator group at 10h20).
The issue is solved.

PRC will contact PES spectrometer experts at XPD to tune polarization monitoring with BKR.

SASE1 XTD2 attenuator arm issue

On monday 7.4.2025, one of the SASE1 attenuator arms (SA1_XTD2_ATT/PNACT/A9) with a 2mm Silicon attenuator got stuck when inserted
EEE reports in the XO meeting today that DOC / EEE helped to unblock and remove it from the beam
(from the karabo-history, I assume this was on monday between 10h00 and 10h30).
This arm A9 is now blocked/disabled with the attenuator out of beam to prevent this to happen again until this issue is fixed.
To fix the issue for good and to re-enable operation of arm A9, an access to the tunnel XTD2 would be needed.
The group in charge of this beamline component is XRO. So far there is no access request.
CTRL (Wajid) reminds that also the karabo device needs to be blocked / unblocked.

This week, SPB/SFX receive SASE1 beam.
SPB/SFX (Chan Kim and Tomas Popelar) confirm that they can work this week without this attenuator arm,
in particular because they have their own attenuators and will not use the XTD2 attenuators.
Thus, for operations it seems that this access could wait at least until next week tuesday.

SASE1 pulse energy drops slowly three times

SASE1 XGM detects three times during the morning some slow drop in puls energies from the SASE1 undulator.
The machine cannot find any correlation with any electron diagnostics.
The XGM-measured beam position indicates no beam position drift (which could then by gradual clipping explain the loss in pulse energy).

7:15 SPB reports large background from non-lasing SASE3 bunches. BKR is informed.  

7:50 BKR analysed situation. Everything concerning the orbits is OK, so the background is due to the standard spontaneous background (about < 1% level of FEL beam). With SASE3 running currently 255 lasing bunches and SASE1 single bunch the intensities will be on a similar level. Recommendation to SPB to close SRAs from 3 mm to maybe 1.5 mm to reduce background. 

5:49 HED called and they have problems with the Laser Sync signal. A change of laser delay is not possibe. We supsect that it is similar to earlier this week at FXE, where a crash of a sync CPU caused a similar error. BRK is informed and tries to reach somebody from sync Group via email (at 6:35, no OCD phone number available) . If this does not work, we will work with the shifts starting at 7:00 on this (DOC and new BKR crew). 

8:45 (see also DESY elog entries): After several attempts LBsync timing works, at least for now. One problem was that the crate was constantly rebooting by itself. Now it is stable, but error could happen again. In that case, BKR should activate expert via email. 

Attachements: Location of LBsync server status in DOOCS and status of XFELcpuSYNCEXP1-3 for last light

7:20 FXE reports a problem with laser synchronisation (yellow warning light and could not change delay). BKR informs the DESY laser sync group. 

7:51 DESY sync group reported that there was a CPU failing about 6 am this morning which led to the yellow warning light. However, synchronisation was very likely all the time ok withing 5-10fs. The CPU was now reset and everything should be wokring now. 

**X-ray delivery:**
* 16 keV, ~upto 1 mJ, 160 pulses
**Optical Laser:**
* None
**Achievements / Observations:**
* Alignement
* Recorded first explosions

The status of the FXE shutter in the Public status display DOOCS panel is incorrect. Here appears as opened, when it is actually closed.

MID called and reported issue with Dachs terminals at the user labs (probably no power). TS was informed. Because the lab are currently accessible (doors are locked open), TS will take care about it on Monday.

X-ray delivery

    up to 188/352 pulses per train (~1 mJ pulse energy)@13.4 keV, 0.5/1.1 MHz

Optical laser delivery

    800 nm, less than 20 fs at sample position, no issue

Achievements/Observations

    X-ray beam de-focused to a few um for data taking

    PP laser aligned

    Data collection for some samples

X-ray delivery

    up to 188 pulses per train (~1 mJ pulse energy)@13.4 keV, 0.5 MHz

Optical laser delivery

    800 nm, less than 20 fs at sample position, no issue

Achievements/Observations

    X-ray beam de-focused to a few um for data taking

    PP laser aligned

    Data collection for some samples