The In-Vacuum RFPD cables needed for HAM1 were re-terminated. Connectors that mate to the feedthrough are the new 5-way coaxial connectors. The connector that connects to the PD was not modified. Total of 11 cables were re-terminated. Cables were tested for continuity and a TDR test was performed using the Keysight FieldFox Analyzer.

D1300278 Qty 7 length 156”
D1300278 Qty 4 length 106”

F. Clara, C. Gray, M. Pirello

This morning I ran a full IPMI sensor scan on all the realtime front ends and h1susauxex could only see one of its two redundant power supplies. I drove out to EX to inspect and found that both PS look fine with green LEDs. One at a time, I disconnected the power cord and pulled the PS out of the chassis, waited until the LED extinguished and then reinserted. This has made no change to the IPMI Sensor reporting. I'll flag this unit as an exception when reporting failed power supplies.

IPMI Sensor h1susauxex:

h1susauxex:   OK     | (2215) Chassis Intru     |                  OK                   |
h1susauxex:   OK     | (2818) PS2 Status        |           Presence detected           |
 

IPMI Sensor h1susauxey for comparison:

h1susauxey:   OK     | (2215) Chassis Intru     |                  OK                   |
h1susauxey:   OK     | (2751) PS1 Status        |           Presence detected           |
h1susauxey:   OK     | (2818) PS2 Status        |           Presence detected           |
 

J. Kissel, O. Patane, I. Abouelfettouh, B. Weaver

Betsy asked Ibrahim to gather some health check transfer functions in air prior to their CP work yesterday. He'd struggled for a bit to drive standard templates on the reaction chain, and called in re-inforcements. We reminded each other that "R0 tracking," or "L2 to R0 damping", or "the L2DAMP path" exists that uses the PUM (L2) OSEMs in feed back to the reaction chain (R0) to keep the chains moving together (ECR E2000011, built into all QUAD front-end models Jan 10 2020 LHO:54416, installed the next Tuesday LHO:54506, quickly and obviously became useful on the ETMs LHO:54556, but only turned on for the ITMs for the first time on Nov 10 2022 LHO:65728). 

It is *not* a DC coupled loop, it's an AC-coupled "velocity damping" controller, but it does have a giant amount of gain with a resgain filter right at 3.3 Hz.

This tracking needs to be turned off during standard M0 or R0 "health check" transfer functions for *all* quads. They go unstable with huge (but standard health check) drive going to the main chain. We've run into having accidentally left these loops on for the ETMs before (LHO:60482), but this is the first time it's popped up for the ITMs, since it's the first time in a while we've characterized the ITMs.

Anyways, we found it, turned the ITMY L2 to R0 damping/tracking OFF (ITMX remains ON), and the main and reaction chain TFs that Ibrahim gathered went without a hitch after turning it off.
These TFs are 
    /ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ITMY/SAGM0/Data/
        2025-04-09_1330_H1SUSITMY_M0_Mono_WhiteNoise_V_0p02to50Hz.xml
        2025-04-09_1330_H1SUSITMY_M0_Mono_WhiteNoise_P_0p02to50Hz.xml
        2025-04-09_1330_H1SUSITMY_M0_Mono_WhiteNoise_Y_0p02to50Hz.xml

    /ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ITMY/SAGR0/Data/
        2025-04-09_1800_H1SUSITMY_R0_WhiteNoise_V_0p02to50Hz.xml
        2025-04-09_1800_H1SUSITMY_R0_WhiteNoise_P_0p02to50Hz.xml
        2025-04-09_1800_H1SUSITMY_R0_WhiteNoise_Y_0p02to50Hz.xml
Pressed for time, we did NOT take all DOFs.
Just wanted to get these TFs mentioned in the aLOG.

Randy, Mitch, TJ, Jennie, Corey, Jim

This morning we pulled the rest of the HAM1 PISI. This part was relatively trouble free, masses stuck to the viton corks a bit, so we put a bit of tension on the chain bridle then tugged on the mass till it popped free. Masses, springs and hardware were kept clean, the support table and risers were set out on the floor. I think vac is up next with feedthrus, the ISI still has to be swapped to a different container in staging.

Thu Apr 10 10:11:06 2025 INFO: Fill completed in 11min 3secs

Morning dry air skid checks, water pump, kobelco, drying towers all nominal.

Dew point measurement at YBM , approx. -44C

Following on Oli's discovery that the MX wind speed was zero for many hours Tue night/Wed morning, it appears that the MX anemometer sticks when the wind speed is below 5mph. The attached plot shows MX (red) and EX (blue) wind speed comparison.

I noticed the same thing when observing MX anemometer from the road side, it look a good gust of wind before it got moving. Tagging PEM.

TITLE: 04/10 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: 0.01 μm/s
    Secondary useism: 0.12 μm/s
QUICK SUMMARY:

Plans for today:

• BSC8 - ITMY and R0 TFs after alignment complete
• HAM1 CRANE/FORKLIFT - SEI Stack removal, continued
• HAM1 ISC prep - Recheck all RMs with FRS ticket issues
• HAM1 ISC prep - check all removed cables for loose screws
• HAM1 ISC prep - Inspect Optics and beam dumps, FC if needed
• HAM1 ISC - rework M12 and M15
• JASON - IAS HAM1 support tube ends?
• BSC1 (via BSC8) - CPY work starts - crew to map beams inside at spool, adjustment continued (Betsy, Robert, Sheila, Tony)

Jonathan, Erik, Dave.

IPMI end station HWS computers:

After the power outage both h1hws[ex,ey] computers' IPMI ports went off-line. I went to h1hwsex this afternoon and reset the computer into BIOS to check that its IPMI network setting were correct, they were. Back in the CUR Jonathan and myself went through the sw-ex-stk setting to ensure that switch2-port8 was on the ADMIN VLAN (yes), was up (yes) and could see somthing was connected (also yes).

I remembered that sometimes old server's BMC cards need a full power cycle to get going again, so at h1hwsey I powered it down and pulled both power cords for at least 30 secconds. When it powered back up I briefly went into BIOS to check the IPMI network settings (all good) and then booted. At this point the IPMI port for h1hwsey was operational again.

Back at h1hwsex I did the cords-out power cycle, which restored its IPMI as well.

I started the EX and EY HWS EPICS IOCs to get the EDC green again.

MY Weather Station

The power outage damaged the 24V Comtrol power suppy for both MY and EY. Erik found a spare PS in EE on Monday and got EY going. This afternoon I found a second spare PS in the MSR and got MY weather station going again.

There was an attempt to calibrate the sliders for the H1:SUS-ITMY_R0_OPTICALIGN_ P _OFFSET And also for Yaw.

Robert & Sheila were inside the vacuum chamber over by GV5 holding up a "Calibration sheet". 
I was tasked to move the sliders back an forth.
H1:SUS-ITMY_R0_OPTICALIGN_P_OFFSET has a range from -410 to +410.
I set the ramp time to 10 seconds, and the stepsize to 880.
At 21:14 UTC I typed in the value to send the slider to -440.
I then took a singular step that took the slider from -440 to +440, and then took the slider back to -440 with a singular step.
This was repeated a few times.
I then changed the step size from 880 to 440 and set the slider to -220.
Then stepped from -220 to +220 with a singular step, and back to -220 again.

I then did a similar process again for H1:SUS-ITMY_R0_OPTICALIGN_Y_OFFSET which has a range from -610 to +610.
So the step size this time was 1220.
The slider was moved to -610 at 21:18 UTC. 
The slider was then stepped over to +610 via a singular click of an arrow key. Then back down to -610 again with another click.
This was repeated once again.

The step size was then reduced to 610 , and the slider was moved to -305. We then stepped up from -305 to + 305 with a step.
the slider value was returned back to -305 and the process was repeated.

I assume that Robert was holding a laminated sheet of graphing paper that we could use as an absolute reference for this slider values to calibrate the beam movements.

 

Randy, Tyler, TJ,Oli,Corey, Mitch, Jim

Starting after lunch today, we launched on starting to disassemble the HAM1 passive stack. First we had to pull the L4Cs we installed IN the optical table. These proved difficult to remove, most of the screws could be removed with a long t-handle 3/16 allen key, but for the 2 vertical L4Cs on the +X side each one had one screw that was difficult to find a way to reach. Corey ended up removing the clamps from his, TJ painfully removed a final screw 1/8th a turn at a time. This took most of the afternoon.

While we chewed on that problem, we also tried pulling the pins holding the optical table to the mass stack. These also proved difficult, it seems like the pins may have been overtorqued. We ended up having to use a wiped down pair of vise grips to assist an awkwardly inserted screwdriver to break all 12 bolts free.

Once the L4Cs and optical table bolts were removed, pulling the table was simple: attach the lifting plate, pull up with the fork lift gently until the optical table popped free, then up and out of the chamber. The optical table is sitting on a pallet between HAM2 and HAM3, probably headed for recycling. Everything else is going to be bagged and tagged for somebody else's project.

Tomorrow we'll finish pulling the masses and support table. 

TITLE: 04/09 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: HAM6 turbo work completed, BSC8 work progressed, and HAM1s passive stack was cleared off, the cabling was removed, and the passive stack's tabletop is on a pallet.
LOG:                                                                                                                                                                                                  

• JIM/MITCH - HAM1 Offload HEPI Setup, disconnect actuators (continued) DONE
• HAM1 - ISC component (continued) (Camilla, Oli, Elenna, Rahul, TJ) DONE alog83836
• MID Station forklift - Transport and Load in ISI de/Install fixtures, wipe down, crane into place  ?
• BSC1 (via BSC8) - CPY work starts - crew to map beams inside at spool (Betsy, Robert, Sheila, Tony)  Partially done alog83841
• Randy - Remove platforms from HAM1 DONE
• HAM1 - Remove all cables form chamber DONE
• HAM1 CRANE/FORKLIFT - SEI Stack removal  Still in progress
• RANDY - Crane 3IFO Flange crate over BT to first stop West Bay for later X-Arm traverse ?
• HAM6 VAC - Move turbo from top to back door (continued) DONE alog83840

• There were some high dust counts at BSC8 at 21:00 UTC but they cleared up after ~10 minutes, 1270 and 320 for 0.3 and 0.5 particles respectively.
• The PSL anteroom had several red alarms of just over 100 counts but this is probably to be expected with the adjacent HAM1 work

Ibrahim, Tony, Betsy, Sheila, Robert

We tried adjusting the pitch of CPY to overlap the optical lever beam spot from the arm cavity side of CPY with the spot from the AR side of ITMY, but the PUM-level inter-chain earthquake stops limited our pitch adjustment. The figure shows that we reduced the distance between the spots we were trying to overlap by a factor of 0.56. If we are going to leave it this way, we should back off a little from this setting.

Travis, Melina, Jordan

Per the updated HAM6 VE drawing (D0901823), we moved the HAM6 turbopump and pump out spool from the top D7 flange to the -Y door BF3 port. The 12"CF ->10" CF adapter, gate valve, pump out spool and turbo pump were removed and replaced with a single 12"CF blank on the D7 flange. We also replaced the turbo with a 500 l/s Leybold maglev turbo compatible with the SS500 pump carts.

The turbo assembly (with GV closed) was pumped down and helium leak checked. Each joint sprayed with a 5s dwell of He, no signal observed above the leak detector background of 3.6E-10 Torr-l/s. Remaining chamberside flanges will be He leak checked during corner pumpdown.

Starting around 22:13 Tue08apr2025 the MX weather station wind speed anemometer stopped recording. The other MX sensors, for example outside temperature, continue to run.

Attachment shows wind speed and temp for EX top row, and for MX bottom row.

J. Oberling, R. Crouch

Today we took pre-deinstall measurements of the position of the optical table surface of the WHAM1 passive stack.  The plan was to use the FARO to measure the coordinates of several bolt holes, using a threaded nest that locates the Spherically Mounted Retroreflector (SMR) precisely over the bolt hole, on both the +Y and -Y side of the chamber.  This, unfortunately, did not happen in full due to the untimely death of the FARO's climate sensor (or the FARO's ability to read the climate sensor, we're hoping for the former).  The FARO cannot function without this sensor as it relies on accurate measurements of the air temperature, relative humidity, and air pressure to feed into a model of the refractive index of air, which it needs to accurately calculate the SMR distance from the FARO.  We did manage to get a few points measured before the sensor died.  I've reached out to FARO tech support about getting a new climate sensor and should hear back from them tomorrow (they usually replay in 1 business day).

Summary

We were able to get measurements of 3 bolt holes, all in the furthest -Y line of bolt holes, and an old IAS monument from aLIGO install before the FARO's climate sensor died.  The results are listed below under the Results heading.  The most interesting thing here is there appears to be an error in WHAM1 placement in the x-axis, as the bolt holes we measured are all ~37.25 mm too far in the -X direction from nominal.  We also set a scale on the wall across from the -Y door of the WHAM1 chamber that is registered to the current elevation of the optical table; placing an autolevel so it sights 150.0 mm on this scale (sighting the side of the scale with the 0.5 mm tick marks) places that autolevel 150.0 mm above the surface of the passive stack's optical table.

Details

We started on the -Y side of the WHAM1 chamber.  The FARO was set with a good view of its alignment monuments and the passive stack's optical table.  We ran through the startup checks and calibrations without much issue (we did see a return of the odd 'ADM Checks Failing' error, which had been absent for about 1 month, but it immediately went away and didn't come back when we performed a Go Home operation).  FARO monuments F-CS026 through F-CS035, inclusive, were used to align the FARO to the LHO LVEA local coordinate system; the 2 standard deviation device position uncertainty after this alignment was 0.016 mm (PolyWorks does 100 Monte Carlo simulations of the device position).  This complete, we started measuring.

First, as a quick test of the alignment we took a look at old IAS monument LV24.  This monument was used to align the WHAM2 ISI during aLIGO install, and its nominal X,Y coordinates are [-20122.0, -3050.7] mm (there is no z-axis coordinate as we were not setting these in Z back then, a separate set of wall marks was used for z-axis alignment).  The results are shown in the 1st attached picture; again, ignore the z-axis results as I had to enter something for the nominal or PolyWorks wouldn't accept the entry, so I rounded to the closest whole number (this isn't even the surface of the monument, it's the point 2" above it where the SMR was, due to use of the Hubbs Center Punch Nest (which has a 2" vertical offset when using a 1.5" SMR)).  Knowing how we had to set these older monuments, since I'm one of the people that set them, I'm not entirely surprised by the X and Y deviations.  The monuments we set for aLIGO install (the LV monuments) were placed w.r.t. a set of monuments used to align iLIGO, which themselves were placed w.r.t. the monuments used to install the vacuum equipment during facility construction (the PSI monuments), which themselves were placed w.r.t. the BTVE monuments which define the interface between the arm beam tubes and the LVEA vacuum equipment, which we then found errors in their coordinates during our alignment of the FARO during the O4a/b commisioning break in 2024.  Not at all surprised that errors could have stacked up without notice over all of those monuments set off of monuments set off of monuments set off of...  Also, take note of the x-axis coordinate of this monument, this will be important later.

We then set about taking measurements of the passive stack optical table.  To map the bolt holes we measured we used an XY cartesian basis, assuming the bolt hole in the -X/-Y corner was the origin.  We then proceeded to increment the number by the bolt hole (not distance), following the same XY axis layout used for the IFO.  Using this scheme the bolt holes for the table corners were marked as:

• -X/-Y: (0,0)
• -X/+Y: (0,32)
• +X/-Y: (36,0)
• +X/+Y: (36,32)

We were able to get measurements for bolt holes (0,0), (14,0), and (25,0).  We were in the process of measuring bolt hole (36,0) (the +X/-Y corner bolt hole) when the FARO's climate sensor died.

To get the coordinates for the bolt holes I used the .EASM file for WHAM1 with the passive stack configuration located at D0901821-v4.  From the assembly, using eDrawings, I was able to get coordinates w.r.t. the chamber origin for the bolt holes we measured.  Those were then added to the coordinates for the WHAM1 chamber, in the LVEA local coordinate system, to get nominal coordinates for the bolt holes.  I also had to add 25.4 mm to the z-axis coordinates to account for the 1" offset of the nest we were using for the SMR; the center of the SMR sits 1" above the point being measured, so I needed to manually add that offset to the nominal z-axis coordinate of the bolt hole.  For reference, according to D0901821 the global coordinates for WHAM1 are [-22692.0, 0.0, 0.0] mm; when converted to the LVEA local coordinate system (removing the 619.5 µrad downward tilt of the X-arm) this becomes [-22692.0, 0.0, +14.1].  The measurement results are shown in the 2nd attached picture.  Notice those x-axis deviations?  Remember the measurement we made of LV24?  Clearly the FARO alignment is not 37 mm off, as the measurement of LV24 showed, so something is definitely up with the x-axis coordinate of the WHAM1 chamber (error in chamber placement?  aLIGO WHAM1 is the iLIGO WHAM2 chamber, moved from its old location next to WHAM3).

Results

We can do some analysis of the numbers we have, although limited since we only have 3 points in a line.  This really only applies to the furthest -Y line of bolt holes on the table, since we weren't able to get measurements of the +Y side to get a more full picture of where the table is sitting, but it's something.  Position tolerances at install in 2012 were +/-3.0 mm in all axes.

• X-axis position: Not much we can do here without knowing what the actual x-axis coordinate of WHAM1 is.  It clearly isn't where the SYS drawings say it should be.
• Y-axis position: ~0.41 mm +Y from nominal
• Z-axis position: ~0.76 mm +Z from nominal
• Pitch: ~99 µrad down
• Yaw: ~83 µrad CCW

I do want to note that D0901821-v4 claims the table surface should be -187.8 mm in LVEA local coordinates (-201.9 mm in global), but this is not the number we used when installing the passive stack in 2012.  In 2012 we used -185.9 mm local (-200.0 mm global), as can be seen in D0901821-v2.  To compare our measurements to the install numbers I changed the nominal z-axis coordinate to match that of our install target (-185.9 + 25.4 mm SMR offset = -160.5 mm) and the results are shown in the final attached picture.

Wall Scale Registered to Current Table Surface Elevation

To finish, we set a scale on the -Y wall directly Crane East of the WHAM1 chamber and registered it to the current elevation of the passive stack's optical table.  To do this we used a scale provided by Jim (the scale was in inches, with 0.01" tick marks) and an autolevel.  We set the autolevel at a fixed elevation on the -Y side of the chamber.  The scale was then placed at each corner of the optical table, starting with the -X/+Y corner, and the autolevel was used to sight the scale; only the scale was moved, the autolevel was fixed (rotated only to follow the scale, but not moved otherwise).  We then averaged the 4 scale readings to get the table elevation, set the autolevel to this reading with the scale back at our starting point (we actually didn't have to move it, thankfully), and then set a scale on the wall using the autolevel.  The 4 scale readings:

• -X/-Y: 5.89"
• -X/+Y: 5.90"
• +X/-Y: 5.90"
• +X/+Y: 5.91"

The average of the 4 readings is 5.9", and since the autolevel was already sighting 5.9" on our starting point at the -X/+Y corner we left it there.  This may seem high, but we had to have the autolevel high enough that we could see over the various components mounted to the table surface.  We then turned the autolevel and set a scale on the wall.  This scale was in mm (since that's what we had), but this worked out OK.  5.9" is ~149.9 mm (149.86 mm to be exact), so we set the wall scale so it read ~149.9 mm when sighted through the autolevel.  So a 150.0 mm reading on this scale (sighting the side with the 0.5 mm tick marks) is ~150.0 mm above the current position of the passive stack's optical table.

This closes LHO WP 12442.

TL;DR - Don't worry about the new models and screens in /userapps/trunk/sus - Brian is developing these for the OSEM estimator project and none of these are (currently) linked to any observatory model.

--

FYI - As part of the project to see if we can improve the noise caused by the OSEMs, we are developing new models and medm screens for the HLTS. Tracking for this ECR is in FRS ticket 32526.  

We are running these at Stanford for testing, and putting them into userapps because we will be trying them on a triple at LHO soon (detail will be in a different log, they are still in flux a bit).

As such, I've created several new things in userapps. These are not linked to anything at either site - I'm putting this note here to reduce potential worry. These are still in development, so I suggest waiting a bit before you look at these.

New Files:

/userapps/trunk/sus/common/models/
HLTS_MASTER_W_EST.mdl   -  library part for M1 with the estimator calculation
SIXOSEM_T_STAGE_MASTER_W_EST.mdl - library part for upgraded HLTS model with the estimator included.

userapps/trunk/sus/common/medm/hxts/
SUS_CUST_HLTS_OVERVIEW_W_EST.adl - new overview screen with estimator

These files are copies of the existing parts as of March 2025, and I added _W_EST to the name of the copy.

userapps/trunk/sus/common/medm/estim/ - directory of new sub-screeens for the estimator

Updated files:

userapps/trunk/isi/common/models/
blend_switch_library.mdl - I added a new model to this library to allow smooth switching between the osem damping, the estimator damping, and OFF.

I'm running this from the new top-level model in

/userapps/trunk/isi/s1/s1suspr3.mdl