X-ray delivery

19 keV, ~ 400  - 450 uJ, 1 - 128 pulses, stable delivery

Optical laser

N/A

Achievements/Observations

Lots of data collection, 659 runs total, lot of nice results, first obsertvations of 3D printing process

Issues

No major issue today

Moning shift summary (31.01 and 01.02)

Acievements:
- SRA recalibrated, cross position on FEL imager found
- VSLIT in SA3 check calibration
- LEPM angle changed for LRGR. Calibration of photon energy server done with help of Ne in GATT.
- Several configurations for SCS have been adjusted/established
 

Late shift 07.02.24
Laurent, Martin

Continued with laser preparation

• optimized SHG
• changed lens to f = 600 mm
• knife edge scans
• found optimum lens position (95 mm) for w0 = 70 um
• fluence characterization --> up to more than 2 J /cm^2
• Coarse timing
• Fine timing

night shift summary 07.02.24

Andreas, Giuseppe

program was to determine horizontal an vertical beam size and then create some single laser shot patterns to determine fluence settings for LIPSS.

PROBLEMS:

• knife edge insensitive to beam sizes smaller than 20um due the large beam jitter of the FEL.
• moved to the camera and curved gratings but then encountered vacuum issue with scroll pump down since noon 07.02. fixed by replacing scroll pump.
• useful camera data could not extracted as we cannot control the TPI shutter and have multiple exposures of the camera. STPulser Macro need to be fixed.
• SCS_XTD10_TPI/DCTRL/SHUTTER in the SCS topic is not found after shutting device down when tracking down device issues.

Night shift summary
Andreas, Giuseppe

• we finished to measure sample 17 and 41 in CARD 06_Y2018F04
• we transferred sample Card_07_Y2018F19
• we started measuring sample 500 nm Ti #26

Problems:

• the frame could not be grabbed properly from the transfer arm, so we decide to vent and transfer manually
• we realized that FEL beam drifted horizontally, we corrected by moving M2 pitch. (The beam did not move at XGM in XTD10, so it must have been some mirror movement)

shift summary
Andreas, Giuseppe

• continued pumpprobe measurements
• around 5:30 we could not see any image at the MTE3 camera (after sample transfer), we tried to fix it but did not work
• we tried to remove the samples from the LLC, the LLC is vented but the lift cannot be moved, needs to be repaired during the day.

Late Shift summary

Achievements:
- recovered the beam overlap
- changed lens position to have larger OL beam
- spatial overlap on YAG
- measured RIXS data delay scan at fixed photon energy

Problems:
- none

## Shift summary night July 28th-29th

Achievements:
- we saw signal on both MCPs (with a voltage of around 1500 V). We used the MCPs to measure XAS at Cu L edge at different theta angles from 120 deg (specular to MCPs) to 70 deg (facing hRIXS). At grazing angles the spectrum is a bit distorted, but just to see the edge is perfectly fine. If there is a diode on the way, the MCP sees  still some fluorescence.
- we saw the direct beam at APD 8 with transmission 0.02 % and 55 V bias voltage.
- we saw signal also on diode 4 and APD5
- the detectors connected are: diode 2, diode 4, APD 5, MCP_BIG and MCP_SMALL
- we looked for signal at rixs on CoO, but it was too weak so we asked BKR to go to vertical polarization
- beam with vertical polarization was transported to the sample
- continie the optimization of hRIXS at Su and hr grating

Problems:
- XAS processor was not working, tried to change date source, but it didn't help.
- diode 6 could not see any signal, probably because it is obstractad by thte antenna back

Program for next shift:
 - finish optimization at Cu edge hr grating

- optimize for Fe, at this geometry or rotated hRIXS.

RC / BKR informs : Beam is down (since 12h10), all beamlines affected

The reason is failure of a quadrupole (power supply) downstream of the dogleg.
The MPS crew is working on recovery, access to XTL ongoing.
RC will inform when new estimates come in on when we can restart beam operation.

Currently affected on Photon side:
- SA1: Naresh (XPD) and Marco (DET) working on Gotthard-II commissioning. Naresh is present at BKR.
- SA2/SA3: Antje + Mikako (XRO) working on SA2 mirror flipping tests and SA3 exit slit check. Both are located at SXP control hutch.
Other XRO members will come in for the afternoon/evening shift work. Antje will inform them via chat.

A ZZ is taking place today, 31.01 at 11:30, in XTD9 to verify and fix the M3 Pop-in screen which is currently blocking the beam. It is not yet clear if this is an electrical or mechnical problem.  

** Update 13:05: ZZ intervention is finished and successful. A mechanical issue due to a loose coupling between motor and spindle was fixed. Machine is running again and SPB/SFX can use the beam.

-Machine status

the cold compressor failure occurred at ~16.30hr today. And it will take around 35 hr to fix it. I will update via email (local contacts for experiments) and Operation Elog tomorrow with more details.

Naresh

SASE1 bunch number was reduced to 10 pulses for no obvious reason. 

Traced it back to a malfunctioning of the watchdog for the solid attenuator (see attached error message)

Deacttivated the watchdog for SASE1 solid attenuator. Re-activated it again.

Issue: SASE1 (SPB?) was requesting 200 pulses at 6 keV with full power with all solid attenuators in the beam. This was a potentailly dangerous situation for the solid attnenuator (!)

After that the team left to go home. Nobody is available at FXE.  Set pulse number to 1.

Checked status of solid attenuator. Seems that plate 1&2 have some vertical cracks (see attached picture)

11:15 SASE1/SPB called that they observed and issue with the SASE1 XGM/XTD2: about every 35 seconds the power reading jumps from 4 Watts to zero and back. It seems to be related to some automated re-scaling of the Keithlyes, which coincides. The fast signal and downstream XGMs do not show this behavior. The concern is that this may affect the the data collection later today. 

12:15 The XGM expert was informed via email, however, there is no regular on-call service today. If this cannot be fixed in the next few hours, the PRC advises to use in addition the reading of the downstream XGM for data normalisation. 

13:15 Theo fixed the problem by disabling auto-range. Needs follow-up on Monday, but for this weekend should be ok. 

BKR called PRC around 06:10AM to inform on vacuum issues at SA1 beamline leading to a lost beam permission for the North Branch.

VAC-OCD found an ion pump in the PBLM / XTD9 XGM presented a spike in pressure that triggered valves in the section to close.

After reopening valves the beam permission was restored; further investigations and monitoring in coming days will continue. Currently all systems work normally.

https://in.xfel.eu/elog/Vacuum-OCD/252

Yesterday two motors of the SASE2 seeding mono were damaged. The mono was exchanged in the afternoon and pumped down. Currently, an issue with the vertical cystal motion is being investigated.  The vacuum improved much faster than expected after this intervention, so the hope is that the tunnel can be searched soon and electrons could go through SASE2 already this afternoon. Watch for updates in the program for SASE2 in the DESY logbook under 'Schedule'.