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.

X-ray delivery

• 9.3 keV, 1-202 pulses at 1.13 MHz, 1.9-2.1 mJ.
• Overall stable delivery.
• L-IBFB could not be activated due to missing missing transfer matrix elements. Missing parameters entered by the expert who happened to be on shift this morning.

Optical laser delivery

• 800 nm, 50 fs, 564 kHz. Overlall stable delivery.

Achievements/Observations

• Installation and alignment of fixed target sample.
• Coarse timing of PP laser.
• Found diffraction of sample.

Issues

• Retracted CRL positions in MDL SA1_XTD2_CRL/MDL/CRL are not up-to-date and do not drive the CRLs to the "out" switch.
• PP laser OXC synchronisation signal dropped out a couple of times. LbSync and LAS informed.

X-ray delivery

• 9.3 keV, up to 181 pulses at 564 kHz, ~1.8 mJ. Overall stable delivery.

Optical laser delivery

• 800 nm, 50 fs, 564 kHz, up to 185 pulses. Overall stable delivery.

Achievements/Observations

• Tested first implementation of new automatic jet alignment device.
• Setup of photon arrival time monitor.

Issues

• No analog output from SPB_MKB_MVE/ACTRL/AX_FINE. Solved by EEE via DOC.
• Issue with MKBs coordinated motions under investigation by CTRL via DOC. Nothing obviously wrong, investigation still ongoing.
• SPB_OHD_SCR/MOTOR/ZOOM and SPB_OHD_SCR/MOTOR/FOCUS not working. Some parameters lost during summer maintenance period. Fixed by DOC/EEE.
• SPB_IRU_INJMOV/MOTOR/Y regulargly going into error state.
• No access to key XFEL/DESY services (elog, Redmine, etc.) for a while.
• SPB optics hutch shutter opened during the night, around 2:10, when we were not present causing a beam delivery interruption of about 5 minutes in SASE1/3.

Shift summary for 10.8.2023

X-ray delivery

• 9.3 keV, up to 181 pulses at 564 kHz, 1.8 - 1.9 mJ

Optical laser delivery

• PP Laser, 800nm, 50 fs, up to 181 pulses @ 564 kHz and 91 pulses at 282 kHz, stable delivery

Achievements/Observations

• Increased MBK_PSLIT aperture to fully fill the mirror's aperture
• Issue with coordinated MKBs motion solved with the help of EEE and CTRL.
• PP laser was aligned to IRU
• Established temporal overlap between PP laser and X-rays
• Continuation of automatic jet alignment testing
• Measured pump-probe data at different delays and fluences

Issues

• Injector Y stage is moving down without giving sany move command, DOC was informed. PLC experts will contact morning shift crew to investigate further
• Astigmatism of PP laser beam prevents optimal focusing of the beam at the interaction point. LAS has been informed

Shift summary for 11.8.2023

X-ray delivery

• 9.3 keV, up to 181 pulses at 564 kHz, 1.8 - 1.9 mJ

Optical laser delivery

• PP Laser, 800nm, 50 fs, up to 181 pulses @ 564 kHz and 91 pulses at 282 kHz, stable delivery

Achievements/Observations

• Continued pump-probe data collection for different delays and fluences
• Continued jet automatic alignment testing
• First test of arrival time tuning with BKR

Issues

• Injector Y stage issue still persists. The reason behind the issue might be a faulty econder, the stage is now in open loop. EEE will check the issue on Monday in detail.

Potentially damaged 1.2 mm CVD in XTD2 attenuator. This feature was not present earlier in the week.

Shift summary for 26.9.2023

X-ray delivery

• 6.3 keV, ~4 mJ, 1-352 pulses at 1.13 MHz
• Great performance and stable delivery with few minor interruptions

Optical laser delivery

• See issues

Achievements/Observations

• Aligned MKB trajectory to 1.5m detector distance configuration
  • Some work can still be done on the background
• Scattering laser setup
• A few runs with silver cubes taken at the end, with some time borrowed from FXE
• Good focus with MKB B4C strip

Issues

• Optical laser not available
• Historical data from some devices unavailable in Karabo. Solved by DOC

Shift summary for 27.9.2023

X-ray delivery

• 6.3 keV, 3-4 mJ/pulse, 1-352 pulses at 1.13 MHz

Optical laser delivery

• PP laser, 1030 nm, 226 pulses at 1.1 MHz, delivered from 9:45 on and was stabilizing over the day
• ns laser for rayleigh scattering, stabe delivery

Achievements/Observations

• Aligned MKB trajectory and optimzed background
• Scattering laser aligned with X-rays references and overlaped with particle beam
• Few runs with sucrose while trying to optimize injection

Issues

• PP laser was still drifting in energy and pointing, better stabilized towards the end of the shift
• Difficulties with injection, tried sevral times and did not improve much
• Slope in pulse energy along the pulse train, up to 40% change from first to last pulse
• Significant background AGIPD after correcting beam trajectory

Shift sumary for 29.9.2023

X-ray delivery

• 6.3 keV, 3-4 mJ/pulse, 1-352 pulses at 1.13 MHz

Optical laser delivery

• PP laser, 1030 nm, 226 pulses at 1.1 MHz, stable delivery
• ns laser for rayleigh scattering, stabe delivery

Achievements/Observations

• Solved the issues with sampel injection
• Collected data without laser for 1 to 2 hours
• PP laser coarse timing

Issues

• Issues with injection, solved later in the shift
• Difficulties to find fine timing
• Issue with migrating data to offline cluster, solved by DOC

On multiple occasions this morning, the number of bunches was reduced to 1 without actions from our side.

Looking at the history of SA1_XTD2_BUNCHPATTERN/MDL/CONFIGURATOR, we noticed changes were applied by this device, presumably originating from one of the watchdogs in SA1. This kind of silent changes is particularly inconvenient and could be easy to miss if one is not constantly monitoring that the number of bunches remains the same. Given that there are dozens of watchdogs in SA1, it is at best cumbersome and time consuming to track the origin. Finding the origin of the restriction needs to be made easier.

X-ray delivery

• 13.6 keV, ~1.6 mJ and up to 352 pulses at 1.1 MHz.
• Beam down at 22:47, not recovered before the end of the shift. Otherwise stable delivery.

Optical laser delivery

• 800 nm, 50 fs, 1 to 176 pulses at 564 kHz pumping TOPAS at 475 nm.
• Intensity modulations through the burst during the second half of the day. Solved by LAS OCD. Otherwise stable delivery.

Achievements/Observations

• Remounting of diagnostics stack under the injector.
• PP laser and X-ray spatial and timing overlap.
• Collected data from noon until beam down towards the end of the shift.

Issues

• Discrepancies between delay calculated by OpticalDelay device and motor encoder position appearing from time to time.
• Karabo GUI crashed twice when after pressing enter while editing a table.

Activities:

• continued tr-RIXS scans
• tried to find ways to mitigate the energy drifts of the mono (see below)
• confirmed in user data that the FEL-PPL timing was not changing (see below)
• setting up for tr-RIXS at beginning of night shift

Problems:

• the mono energy has been drifting, presumably due to warming of the grating.
• automatic correction of the elastic line in the RIXS data was not working reliably
• we suspected a timing drift, but it seems that the monitor (photodiode + oscilloscope) itself is drifting. That's a new one.

Activities:

• Found coarse and fine timing between FEL and PPL at 266nm
• Set up for tr-RIXS during the night

Problems:

• 2 fastADC channels appear to be dead.
• Optical locking of the PPL syncronisation system took a very long time (> 30 minutes)

Activities:

• Measured tr-RIXS spectra on user sample in silane solvent

Problems:

• Sometimes the PPL shutter cannot be opened from the control room after searching the hutch.

Activities:

• correctly positioned magnet
• moved detector upstream and found small beamstop
• Recorded SAXS
• Started tr-SAXS

Problems:

• The SAXS images from laser-excited samples showed unexpected variation between different size rings, central point (ie not a ring) and no scattering. 

Activities:

• Investigated SAXS scattering instability and found it to come from the pointing variation of the PPL
• Recorded microscope images of the PPL spot of the pBN to quantify the pointing for different spot sizes
• Enlarged the beam and measured pumped SAXS. Results seem better than before.

Problems:

• PPL pointing is not stable enough for consistent pumping effect in the probed area.
• Sample scanner x motor went into error due to interaction with the magnet and had to be coaxed back into operation.
• FEL down with cryo problem.

achievements

• optimized EOS signal from FEL-induced THz emission from STE on Sa of PAM
• reduced chirp to increase timing sensitivity to 9fs / pixel of PAM
• STE-based PAM measurements at fixed delay and delay scans. 
• after FEL down at 6am, continue with PAM measurements without BAM fast feedback mode (stopped after FEL back)

issues

• none

Achievements

• Observed first EOS of THz emitted from FEL-pumped STE on SiC and Si membranes
• Explored fluence dependence and damage limits
• Explored sample heating with pulse repetition rate
• Measure timing jitter of FEL with and without longitudinal feedbacks engaged

Problems

• DAQ was losing trains. Problem solved by DOC.

X-ray delivery

•  9.3 keV, 1-120 pulses,
• good stabiltiy, lowish flux ~900uJ, but experimental requirements were met

Achievements/Observations

• Finished doule slit measurements at micron beam
• Alignment to direct beam
• Sample position for the sand paper found
• Some sand paper test speckle patterns measured

Issues

• Alignment was a bit painful without the NKB and EHC cameras - switch to ZYLA at EHC made ALAS alignment much easier
• diff pump does not transmit much of direct beam without interference and requries tight power slits (known limitation)

Instrument status

• AGIPD HV off.
• AGIPD gate valve closed and pinned.
• Attenuators set to thickest diamond.
• Vacuum valves closed.
• EHU PSLIT closed around direct beam to approx 1.2 x 1.2 mm
• sample moved up by 10mm so both rows accessible in direct beam
• current 'focus' sample position is approx location of sandpaper from evening measurement (lower row, darkside), 10mm in +x moves out of beam

To do for next shift

- continue direct beam speckle measurements (See entry elog:138)
- quite a bit of scattter on AGIPD from direct beam and especially sandpaper samples.
- transmissions of at least ~1 % level are detector safe (no pixels in AGIPD medium gain)