SPI has been added added as a subsytem in the userapps directory tree.  MATLAB can open SPI models by name and h1build should build spi models (not tested yet as there are no models to build).

You'll need to wait an hour after this post for puppet changes to propagate and log out and back into a workstation for the MATLAB path update to take effect.

Fri Apr 03 10:12:27 2026 INFO: Fill completed in 12min 23secs

TITLE: 04/03 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: None
CURRENT ENVIRONMENT:
    SEI_ENV state: MAINTENANCE
    Wind: 5mph Gusts, 3mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.17 μm/s 
QUICK SUMMARY:

GV7 was closed last night (~530pm)--still only soft closed to the X-arm (Y-arm has been [hard] closed ~2weeks).

Closeout work in HAM1 will need to continue today and then move tables away from HAM1 in prep for a Monday vent.

Betsy informed me that the commissioners were done with the peek along the X-arm and I closed GV7, once again it does not want to hard close, currently sitting at "soft close" with 50 psi of instrument air in an attempt to close it.
I tried increments of 10 psi with the new regulator, I took the pressure up to 90 psi, and it sat there for about 30 minutes, no luck closing.  Probably the gate valve is not "hard closing" due to the leaks within the gate valve's piston system.
I've set the pressure down to 50 psi and left it and maybe it will hard close, with the leaks present lots of air is wasted.  Also, this configuration allows for crane usage along the XBM from now on.

Following yesterday's work (alog 89745), ISCT1 was moved in place (but not landed, so the table is much higher than usual for now) to check the in-air beams.

ALS beam from the PSL table as well as green ALSX beam:

Was already good. See ALS_beampos.jpg. 

Note that ALSY beam is supposed to be at the same height as ALSX but shifted horizontally by 10mm or so in -X direction on the periscope mirror. According to Mike Smith's L1200282 Table 1 (which is the table we should use though there are other similar tables in that document) ALSY is shifted by 8.5mm in +Y direction relative to ALSX on the septum window (and the two beams are diverging after 3" mirror in HAM3).

REFL air and POP air:

REFL was already hitting the ISCT1 top peri mirror but was close to the +X edge (REFL_before.jpg). POP air beam was coming to the same mirror mount as was described back in May/25/2025 in  alog 84558 (especially this picture in that alog) though I didn't know/remember. (Turns out that I was away for a week when that was done, my recollection only included my May/09/2025 alog 84334.)

I didn't like that POP and REFL beam are both at the edge of the mirror and "fixed" it, i.e. I undid the work people did on May/25/2025 (sorry). I adjusted 90:10 air-vac splitter (M12 in layout.png) to make sure that the beam is not close to the edge of the last steering mirror for the POP air path (M16), and used M16 to steer the POP beam back to the top POP periscope mirror in ISCT1.

I found that the beam was too much in +X direction at the bottom and didn't hit the bottom periscope mirror even when I maxed out the YAW adjustment range of the top peri mirror. (My guess was that people found that back then and decided to shift the POP beam onto the REFL top peri mirror, but Sheila didn't think so even though neither she nor Camilla remembered exactly why.)

Anyway, since I still didn't like that the beams are both close to the edge of the mirror, I decided to keep the "new" configuration where REFL hits REFL periscope and POP hits POP periscope.  

I shifted the REFL top periscope mirror by ~1" in +X direction so the REFL beam is not close to the edge of the mirror. Betsy took the picture of the REFL beam on the top periscope mirror.

The REFL beam hits the bottom periscope mirror. Further adjustment is necessary downstream.

For POP, since the only thing lacking was the adjustment range of the top peri mirror, at first I wanted to swap the mirror mount (ultima with 2 actuators) with a 3-actuators variation to gain more adjustment range, but it turns out that the adjustment knob on the "third" actuator would interfere with the bracket on which the mirror mount is bolted. As a quick fix, I merely "pushed in" the fixed pivot pin to tilt the mirror in a disired direction, which worked. See top_POP_peri_mechanical_tweak.jpg. 

I also steered down the beam by M16 a bit, shifted the top POP peri mirror in +X direction by ~1" like I did for the top REFL peri mirror, used M16 to steer the beam again, and ended up with an OK position on the top peri mirror. See POP_top_peri_beamPos.jpg.

The beam hit the bottom peri mirror, it's not centered but is OK. Further downstream alignment should be done in the future.

Finally,  POP_REFL_at_VP_position.jpg shows the REFL and POP air beam when the card was held very roughly at the location of the viewport. This more or less agrees with one of the pictures (https://alog.ligo-wa.caltech.edu/aLOG/uploads/84344_20250509211310_PXL_20250509_231320536.jpg) in my May/09/2025 alog and I'm positive that the POP won't be clipped by the VP.

REFL_AIR and POP_AIR Beam dumps:

REFL air goes to beam dump when the REFL beam diverter closes (forgot to take picture but not surprising as REFL air path wasn't touched).
Unfortunately I forgot to check if the POP air beam goes to the beam dump when the POP beam diverter closes. This needs to be checked the first thing tomorrow.

TITLE: 04/02 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: The HAM1 work continues, ISCT1 was moved back into place.
LOG:                                                                                                                                                   

• The megaclean room around HAM6/7 was turned on in the morning and will be left on for ~24 hours as a test. ZONE4's temperature has risen due to this.

Opslogin can still run 4 Different cameras at the same time.

I logged into CDSWS25 as myself and opened 6 FC_TRANS_GR camera feeds, because it currently has good fast flashes. No issues at all.  all 6 show perfectly.
I then closed all but one, then opened PRM and i get stuttered screen tearing and artifacting. infact any 2 different cameras will cause this to happen.

Graphics issue?: 
putting them on different screens did not help.
Reducing number of physical hardware monitors from 2 asus screens to 1 did not sold the issue. nor did reducing the resolution. So Perhaps this is not a graphics issue. Because I can also display youtube videos as well.

Network Bandwidth limitation? : 
I pulled up htop and noted the bandwith use.
For just FC_TRANS_GR alone the RX bandwith is around ~420KiB/s. 
For just PR3 alone the RX bandwith is ~110KiB/s 
and PRM is about ~120 KiB/s
but if I open PRM and PR3 at the same time I get  stuttered screen tearing and artifacting, even thought the RX bandwidth is only  230 KiB/s. 
And if that was the limit od the bandwidth then why would FC_TRANS_GR perform so well since it's RX bandwidth is at 400+ KiB/s. So perhaps this rules out a network bandwidth limitation.

I then installed VLC on this workstation and played a random video that I downloaded from the CDS_DEV Mattermost chat and  played that on loop with no issues.

Then I ran a Gstreamer test command:  gst-launch-1.0 videotestsrc ! autovideosink
And that seemed to work well. then I ran 2 with out issue.

I suggested to Erik that we reboot the server, to see if it might help. 

Oli, Camilla, Sheila

Yesterday Camilla noted that she could not restore filter cavity flashes by restoring FC1 pitch top mass osems when the temperature shifted because the HAM5/6 cleanroom was on 89729.   

Because we can't look at filter cavity flashes while HAM7 is vented, we rely on retro reflecting the beam off FC1 to point it down the filter cavity. 

During this last vent, the cleanroom was turned on Dec 4th, where you can see the tempature rise, the top mass osem shows a shift of -205urad, the bottom mass osem shows a shift of +44 urad.  The chamber was vented December 8th, top mass osem shows a shift of +300 urad, bottom mass -77urad.  There was another shift in the osems on Decmember 23rd, Oli tracked down that Travis turned on the purge air at this time, top mass osems shift +167 urad, bottom mass osems shift -29 urad.  (The top and bottom masses always show different directions, top mass is 4-5 times larger shift than the bottom mass). 

We left the FC1 slider at the setting it had in O4, and aligned the new OPO to retro reflect off this alignment.  On Jan 20th, 88806, we noticed that the osems said FC1 pointing was different from O4, so we moved FC1 sliders by -175 urad to bring the top mass osems back to where they were in O4.  Looking at the bottom osems, this was a shift of -200 urad in the wrong direction, so this attempt to correct for the shifts seen by the top mass actually introduced a larger alignment shift than all of the other changes.  

This morning, Camilla and I placed two irises on SQZT7 in the FGCS reflection path.  We hope that we can restore FC1 pointing using those irises, and then use that as a reference to check FC1 alingment once we vent.  We moved FC1 by 60 urad in either direction and can clearly see the beam clipping on the irises.  We turned the cleanroom back on, and will try to see if this can restore the alignment tomorow.  

Camilla put FC1 back to it's PIT slider position during the vent, ~50urad, gave us light on SQZT7 IR and the HAM7 WFS, so this is close to reproducing the FC1 alignment that we used during the vent. 

So, the conclusion is that my mistake during the vent was to try to use top mass osems to correct for the changes in FC1 alignment.  

J. Kissel, S. Koehlenbeck
H1 SUS-R1 D0902810, S1301885
TIA D1002481-v3, S2500711

Finished with all required assembly and testing of the SPI pathfinder's in-vac ISIJ Reflector assembly (D2400102), we packed it up such that it's install ready. That means it's supporting QPD photodiode transimpedance amplifier, whose [V/A] impedance has been measured and tailored to suit a 10 [V_p] differential ADC input (see 89739) is no longer needed in the optics lab. As such -- we moved it from the optics lab to its final location in the LVEA -- in the U6 position of SUS-R1 by HAM2.

Pictures:
    BEFORE installation
    AFTER installation
    S-NUMBER and U-Height zoom for confirmation.

We have not cabled up any of its inputs or outputs, but will do -- per D2400111 -- so in the fullness of time.

Thu Apr 02 10:16:29 2026 INFO: Fill completed in 16min 25secs

TITLE: 04/02 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: None
CURRENT ENVIRONMENT:
    SEI_ENV state: MAINTENANCE
    Wind: 4mph Gusts, 2mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.21 μm/s 
QUICK SUMMARY:

• HAM1 and SPI work continues
• ISCT1 to be moved  back into place today
• LVEA temps look nice and stable

S. Muusse, G. Bolingbroke, C. Compton

The new QCL laser 0922 was installed in the setup to replace the broken 0920 unit and has been turned on and its working. Thermal paste got on the output lens during storage/transport and but we cleaned off using tissue and isopropanol. The main path alignment has been completed but the pickoff paths havent been checked and lenses havent been replaced. The new unit requires a slightly different lens position described in the yaml file which will hopefully be installed tomorrow. 

On Monday I had a good alignment for the FC, see 89694  and that alog's attached screenshot. Yesterday we went there and had to touch up FCs a little to get flashes. Today for the same sliders was even worse witha very PIT misalinged FC Green beam, see attached, in the same FC1 PIT slider potion, the osems were 150urad off, attached. When I brought us back to the top mass osem positions for all optics (ZM1,2,3,FC1,2 and ZM2 PSAMS) we have no green flashes in the FC, just a single pass green beam, attached. 

1.  Why is the FC1 top mass osems drifting 150urd in 24 hours
2.  We don't seem to be able to trust the osems as going back to them gives us no FC flashes.

Rahul did in-air TF's 75830