Commissioning records: 2026
Summary
- [Enter overarching points from the year here]
February 13, 2026
Beam motion characterization
Since the PGM cooling line repairs in July 2025, there have been concerns that the beam is moving with energy and possibly time. To troubleshoot, beam images were captured at the various flurescence screens throughout the beamline. The 1200 l/mm grating was used (M2 gold mirror spot #2, 1200 l/mm grating spot #3, CFF = 1.7), and images were captured at energies between 100 and 2000 eV.
Diagnostic module 7 (DM7), fluorescence screen 13 (FS13)
Scan IDs 104893-105391 are energy scans characterized on FS13, which is downstream of the RSoXS station. The M4CD mirrors were moved out of the beam path, and the RSoXS slits were opened all the way.
A sample energy sweep movie is available here: File:20260224-3 v1.mp4
The beam shows a consistent vertical shift when crossing from 1100 eV to 1200 eV. Finer scans have not yet been performed to determine if this is a continuous or discontinuous transition. These energies are not routinely used for RSoXS measurements, but this jump may correlate with more subtle beam motions at other energies.
Other than this abrupt vertical jump, there appears to be a diagonal motion of the beam with energy; this can be seen in the beam images although it is not apparent in the linecut plots. From 100 eV to 1100 eV, the beam image appears to move in the downward outboard direction and then the opposite direction in the downward energy sweep. From 1200 eV to 2000 eV, the beam appears to remain more stationary. The beam also appears to show multiple vertical streaks (e.g., at 900 eV), which may exacerbate the apparent flux on a sample as the beam moves during an energy scan.
There are numerous instances when the monochromator does not reach the desired energy setpoint, which results in no visible beam, likely due to a mismatch between the grating angle and EPU gap. Examples include scan ID 104894 at 319 eV, scan ID 104895 at 369 eV, and scan ID 104896 at 333 eV. This behavior seems to be most common in the 300-400 eV range. One possibility is that there may be a hardware issue at the motor angles associated with these energies. One possible workaround may be to revisit how energy motions are performed and to use software iterations to ensure that the correct energy is set.
February 11, 2026
Liquid flow cell transmission NEXAFS measurements
The hummingbird TEM liquid flow cell was used to run transmission NEXAFS measurements on various aqueous mixtures. The DM7 large photodiode was used to detect transmitted photons. Open-beam measurements appeared reasonable and similar to past measurements. However, when beam was passed through an empty flow cell that had nitrogen gas flowing through it, the photodiode signal showed oscillations that were reproducible with energy. These oscillations were especially prominent at the carbon K-edge.
Although the photodiode gain was increased by a factor of 100 going from open-beam (500 nA/V) to flow cell (5 nA/V) measurements, this is likely not the cause of the oscillations. Dark signals across a similar time scale did not show these oscillations, suggesting that stray light also is not a significant contributor.
A time scan scan performed at 270 eV showed mild oscillations, but the amplitude was much lower than that seen in the energy scans. Similar patterns are also seen in the I0 gold mesh that is upstream of the liquid flow cell.
The oscillations showed significant dependence on the the inboard-outboard offset of the flow cell position, suggesting that the oscillations are produced by how the beam hits the flow cell. These oscillations were not seen during liquid cell measurements in the June 2024 and December 2024 beam times. The slit 1 settings used during those beam times were used to re-run these offset scans, but the oscillations were still present.
Similar scans also were performed with multiple iterations of retracting the flow cell and then returning it to its optimal position. The energy scans showed identical signals, suggesting that the motor position is reproducible, and that these oscillations can be normalized out reliably.
It is hypothesized that these oscillations may be due to the possibly misaligned roll of the M2/PGM. As the beam moves with energy, the changes in beam flux might become more apparent through the flow cell, which has significantly narrower windows than typical silicon nitride windows used for solid samples. Future investigation of this issue might involve scans on the I0 gold mesh with slits 1 closed to a very narrow aperture.
February 2, 2026
Resolved: Photon shutter 7 interlock error
After the NEXAFS station and M5 mirrors were removed in the downstream region of the beamline, photon shutter 7 (PSH7) could not be opened even though PSH8 was closed downstream, the EPS-interlocked gate valves between PSH7 and PSH8 were open, and vacuum pressures (i.e., the vacuum switches at the microcal and LARIAT1 stations) were well below the permissible upper thresholds.
After significant troubleshooting, it was identified that the PSH7 interlock depended on the status of GV30, which was downstream of PSH8 and had been removed along with the M5 mirrors. Two steps were taken to resolve the issue, after which PSH7 could be opened. Further details are on this slack thread: https://nsls2.slack.com/archives/C09GJKMQGQ2/p1770040389768589
- A bypass wire was set up in the Drop_XF-2 electric box on the inboard side of SST2 downstream of the RSoXS motor controller and pressure gauge cabinets. An orange jumper wire was placed from slot 7 (IB8) pin 6 to slit 3v (VTM) pin 1 and labeled “GV30 BYPASS”. A white wire with a blue errul is hanging disconnected near the IB8, which was the open limit signal of GV30.
- Setpoints for the uninstalled pressure gauges were changed. These gauges are located in the RG:E1 cabinet on the outboard side of the QAS stairs. On the VGC:13 unit, the VS28-M5C-052 setpoint was changed from ENABLE to SET (SP5, channel B1), and the VS28-M5C-058 setpoint was changed from ENABLE to SET (SP11, channel C2). On the IPC:14 unit, VS28 M5C (labeled 049) was changed from "Pressure" to "Remote"
The likely cause of this incorrect interlock is due to various components being added to the SST1 beamline over time, and the EPS logic not being updated. It would be useful to draft a new EPS logic map with updated interlock dependencies such that irrelevant components do not unnecessarily lock other far-off components. In the past, GV30 would interlock PSH7, PSH10, and PSH4; the latter two gate valves had been removed from the interlock dependency, but not PSH7. These maps should be revisited when major hardware changes are made to the beamline. As the EPS software is accessible only by limited staff, it would be good to store a copy of the EPS maps with the beamline staff for quicker reference. It was noted that when LARIAT1 was vented to remove the NEXAFS station in December 2025, the vacuum switch to interlock PSH7 did not get tripped; it would be good to investigate this further. No other errors were seen on the HMI screen (which a floor coordinator could reset), and only an EPS interlock was visible.
For reference, there are several gate valves between PSH7 and PSH8, but only GV29 should be EPS-interlocked. GV29A through K are not programmed through EPS, and they can be shut while PSH7 is opened.
January 30, 2026
Greateyes WAXS camera leak repairs
The leaks in the cooling circuit were patched by applying sealant (Vacseal, SPI# 05052-AB, Lot#1250812) to the leak locations from the vacuum side. To set this up, the air-side of the camera was pumped down very slowly especially between 1 and 0.1 bar. Primarily, vacuum was needed inside the cooling lines to help pull in the sealant, but the entire air side was evacuated so that the rubber hoses connecting to the cooling circuit would not collapse. As the air side was not designed for routine use under vacuum, there are risks such as the outgassing of thermal pads, adsorbed water in the circuit boards, and lubrication (e.g., in fan bearings). The camera was positioned upside down with the sensor pointing downwards so that the sealant could be pulled into the leak via both gravity and the vacuum on the air-side.
An alternative approach could have been to apply the sealant from the inside of the cooling circuit via the air side. However, there would have been a risk of clogging the circuit, altering the thermal conductivity of the cooling lines, and contaminating the sensor with the sealant as it is pulled into the leak via the vacuum side. Also, taking apart the air-side casing would pose the risk of damaging the thin cooling hoses and plastic hose barbs/clamps that appear to be for one-time use.
In any case, it is important to note that the sealant is a temporary patch-up, and it is unclear how long it will withhold the water flow. Normally, Vacseal is meant for use against air-vacuum interfaces and can work for leak rates up to 2e-3 Torr L/s. Although the cooling line leak is an order of magnitude below this threshold, the Vacseal may get peeled off from continuous exposure to water and the coolant additives. Certain epoxy materials might withstand this leak better, but the locations of the leaks (e.g., under the plastic frame holding delicate wires) is inconvenient to properly apply the epoxy. The aim is to use the Greateyes camera for a few months until a new camera is ready to be installed.
January 23, 2026
Beam alignment
A thorough beam characterization was not performed. The optics were simply restored to the settings used during prior beam times
| Description | Process variable name | Initial values at the start of beam time,
500 mA ring current |
Final values at by the end of beam time,
500 mA ring current |
|---|---|---|---|
| EPU60 front-end slit h size (inboard-outboard direction) | FE:C07A-OP{Slt:34-Ax:X}size | 1.5 | 1.5 |
| EPU60 front-end slit h center | FE:C07A-OP{Slt:34-Ax:X}center | 0.5 | 0.52 |
| EPU60 front-end slit v size (up-down direction) | FE:C07A-OP{Slt:34-Ax:Y}size | 1.5 | 1.5 |
| EPU60 front-end slit v center | FE:C07A-OP{Slt:34-Ax:Y}center | -0.6 | 0.35 |
| FOE pink beam slits 01, outboard | XF:07IDA-OP{Slt:01-Ax:O}Mtr.RBV | 3 | 3 |
| FOE pink beam slits 01, inboard | XF:07IDA-OP{Slt:01-Ax:I}Mtr.RBV | -5 | -5 |
| FOE pink beam slits 01, top | XF:07IDA-OP{Slt:01-Ax:T}Mtr.RBV | 5 | 5 |
| FOE pink beam slits 01, bottom | XF:07IDA-OP{Slt:01-Ax:B}Mtr.RBV | -5 | -5 |
| Mirror 1 X (inboard-outboard) | XF:07IDA-OP{Mir:M1-Ax:X} | 1.3 | 1.3 |
| Mirror 1 Y (up-down) | XF:07IDA-OP{Mir:M1-Ax:Y} | -18 | -18 |
| Mirror 1 Z (upstream-downstream) | XF:07IDA-OP{Mir:M1-Ax:Z} | 0 | 0 |
| Mirror 1 Pitch (rotate along up-down axis) | XF:07IDA-OP{Mir:M1-Ax:P} | 0.57 | 0.57 |
| Mirror 1 Roll (rotate along upstream-downstream axis) | XF:07IDA-OP{Mir:M1-Ax:R} | 0 | 0 |
| Mirror 1 Yaw (rotate along inboard-outboard axis) | XF:07IDA-OP{Mir:M1-Ax:Yaw} | 0 | 0 |
| Mirror 3 X | XF:07ID1-OP{Mir:M3ABC-Ax:X} | 23.7 | 24.2 |
| Mirror 3 Y | XF:07ID1-OP{Mir:M3ABC-Ax:Y} | 18 | 18 |
| Mirror 3 Z | XF:07ID1-OP{Mir:M3ABC-Ax:Z} | 0 | 0 |
| Mirror 3 Pitch | XF:07ID1-OP{Mir:M3ABC-Ax:P} | 7.9 | 7.78 |
| Mirror 3 Roll | XF:07ID1-OP{Mir:M3ABC-Ax:R} | 0 | 0 |
| Mirror 3 Yaw | XF:07ID1-OP{Mir:M3ABC-Ax:Yaw} | 0 | 0 |
Troubleshooting: solid sample bar imager camera not connecting
Sample position calibration
It was noted at the beginning of the beam time that the solid sample x (inboard-outboard) encoder cable was disconnected from the encoder at the beginning of the beam time. It is possible that this cable got disconnected either accidentally or on purpose in December 2025 when the WAXS camera was removed from the chamber. After reconnecting the encoder cable, the user offset was changed from 48.1 mm to 59.480 mm to return to its prior position.
Energy calibration
As had occurred during the December 1-4, 2025 commissioning time, the PGM and M2 encountered following errors during the downward energy direction (e.g., moving from 350 eV to 250 eV). Restarting the MC07 softioc seemed to make this issue stop.
Troubleshooting: Guacamole connection issues
During the beginning of the beam time and the few days prior to the beam time, there were issue connecting remotely to the RSoXS Control computer via Guacamole. However, this issue stopped later on January 23, 2026. DSSI investigated, but did not find the root cause of the issue.
For those with access, further details are available here: https://nsls2.slack.com/archives/C09GJKMQGQ2/p1769179381292279
Troubleshooting: RSoXS analysis computer
Since January 2026, the RSoXS analysis computer has been experiencing some issues. Occasionally, the computer restarts on its own and goes to a white HTTP(s) Boot screen with the error "Failed to find IP address". After pressing okay on the error message and pressing ctrl + alt + delete, the computer appears to restart and then returns to the HTTP(s) Boot screen. Performing a hard shutdown and then starting up the computer results in a normal startup process. However, the HTTP(s) Boot screen returns several hours later.
A (possibly) separate issue is that on startup, a SupportAssist | On-board Diagnostics screen had appeared with the messages "Time-of-day not set - Please run SETUP program." and "Invalid configuration information - please run SETUP program." After hitting continue, some updates were performed, and then the startup performed normally. This only occurred once so far.
At one point, the computer also showed a black screen with the message "Your device ran into a problem and needs to restart. 0% complete". It remained stuck at 0% overnight. A hard shutdown followed by powering back on resulted in a normal startup.
Tiled ReadTimeout errors
During this beam time, the TiledInserter class was deleted from the beamline codebase. The Tiled version had not been updated, which resulted in multiple ReadTimeout errors. After this, the Tiled version was updated. It will need to be verified during a future beam time if the errors persist. For more details, see this slack thread: https://nsls2.slack.com/archives/C09GJKMQGQ2/p1769457130578279