Elenna, Matt, Camilla. Continuing ISC component inspection and prep for re-installation from 83858. 

Elenna, Matt and I continued to first contact the optics in pans 1 and 2:  M7, M11, M12 (new 90/10 BS), M13, M15 (New 50/50 BS), M16, M17, M18. After again inspecting some of those we cleaned yesterday, we decided to re-clean some. Some needed multiple first contacting, they aren't all perfect (there is a 1" long incredibly hard to see line on M15 and a mark in the center of M18 photo that I will ask a second option on), but otherwise we are calling these two pans of optics ready for re-installation. 

For M15, I installed the picomotors that I removed from the right handed mount into a left handed siskiyou mount. I installed the manually adjustable actuators removed from the left handed mount into the right handed mount, this will be stored. Notes on how to do this are attached.

Still to be done: decide if M15 and M18 are okay or need swapping, clean optics in pan 3; inspect periscope mirrors; swap out any glass beamdumps we can. 

TITLE: 04/11 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: BSC8 work finished up and doors were put back on, HAM1 work continues, the ISI is all packed up and ready to move over to its new home.
LOG:

• BSC8 - ITMY and R0 TFs after alignment complete DONE alog83876
• HAM1 ISC prep - check all removed cables for loose screws DONE
• HAM1 ISC prep - Inspect Optics and beam dumps, FC if needed Ongoing
• HAM1 ISC - rework M12 and M15 DONE
• HAM1 ISC prep - Recheck all RMs with FRS ticket issues DONE?
• JASON - IAS HAM1 support tube ends?
• BSC8 - Prep for Closeout DONE
• BSC8 - DOOR ON DONE
• HAM1 - Prep for ISI install DONE alog83879
• VAC Start Feedthru Swap Ongoing?

Travis, Betsy, Randy, Jordan

- BSC8 -X door re-installed with one round of bolt torquing (will perform another round Monday), purge air increased prior to door install, then purge valve at YBM closed. Corner volume has slight overpressure and will be blown down to atm. prior to pumpdown

- Continued installation of HAM1 electrical feedthrus

- Scroll pump staged for CP1 RGA pumpdown and bake-out

J. Freed,

Today, with the gracious help of K. Kawabe, I took power meaurments of the SPI Pickoff BS (BST11) and its spare using S-polarized light

Due to the limited time and person power, we used a S121C PD to take these measurments, which we now realize has a 7% uncertainty at 1064nm with a >1mm diameter beam. Although we relized that the beam was too large after we finished the measurment of the main optic and added a lens to focus the beam during the spare measurement, we have no idea if the beam was ever below the 1mm threashold. As such even though we were using a PM100D power monitor which has a resolution of 0.1 mW, we have to quote an uncertainty of 10% of the final value for our meaurments. This is colaberated by the fact that mulitiple measurments of the same beam could yeild different reults when the PD was taken out of the beam path and put back in, but remained steady if left alone.

SPI-BS-PWR_MEAS.png Shows the measurment set up. The only pick off that was available was p-polarized, as such, we added another half wave plate/PBS combo to get S-Polarized light to our BS

There also existed a ghost beam from the AR-Coated wedge side of the BS that was not taken into acocount for the main optic but was for the spare. Though we dont think the ghost beams affected this measurment as they were 3 orders of magnitude of power below the main beams.

SPIPBSRATIOMEAS-3.txt is a text file containing extra notes as well as the power values measured. The power ratios were found by taking an average of all the trials and then divided by the power we measured just before the beam splitter.

J. Kissel

Figured I'd make the same in-air vs. in-vac comparison of the whole 6 x 6 transfer function matrix for H1 SUS PR3 like I did for SR3 in LHO:83831.


                 D R I V E   D O F 
          L     T     V     R     P     Y

     L    --    meh   meh   meh   eand  YI
 
R    T    meh    --   nd    eand  meh   meh
E 
S    V    YI    YI    --    nd    meh   nd
P
     R    meh   eand  YI    --    YI    meh
D 
O    P    eand  YI    YI    YI    --    nd
F
     Y    YI    nd    nd    nd    nd    --

Recall the legend is 
  YI = Yes, Interesting. DC response magnitude is a bit different between vac and air, but not by much and all the resonances show up at roughly the same magnitude.
 meh = The resonant structure is different in magnitude, but probably just a difference in measurement coherence
eand = The cross coupling is expected, and not different between air and vac.
  nd = Not Different (and unmodeled). The cross-coupling is there, but it doesn't change from air to vac.

(1) For some reason, the data quality on the upper diagonal is worse for the PR3 in-air TFs vs. SR3's but better on the lower diagonal. The "mehs" in PR3's cases are more "man, I wish the coherence was better so we could make a better statement."
(2) For the most part, the same DOFs that are "Yes, Interesting" for PR3 are "Yes, Interesting" for SR3.

Needs a more careful study, but we're only looking at crappy in-air vs. good in-vac data because we're vented right now, and we want to see if it's sensible to measure these things in air, fit the data, and trust that that fit will work in vacuum. 
Given that we're seeing *any* of these elements as "Yes, Interesting -- there's a difference between in-air and in-vac" means that we're getting scared away from do that -- the problem is hard enough! We'll probably just end up waiting for the SUS to be back at vacuum in a few weeks.

Laser Status:
    NPRO output power is 1.839W
    AMP1 output power is 69.11W
    AMP2 output power is 139.0W
    NPRO watchdog is GREEN
    AMP1 watchdog is GREEN
    AMP2 watchdog is GREEN
    PDWD watchdog is GREEN

PMC:
    It has been locked 1 days, 3 hr 1 minutes
    Reflected power = 22.81W
    Transmitted power = 104.6W
    PowerSum = 127.4W

FSS:
    It has been locked for 2 days 23 hr and 35 min
    TPD[V] = 0.8157V

ISS:
    The diffracted power is around 4.2%
    Last saturation event was 4 days 5 hours and 23 minutes ago

Possible Issues: None reported

Corey, Mitch, Randy, Jim

This morning we finished the gross cleaning of the outside of the storage container for the HAM1 ISI. This sat outside for many years so we started with pressure washing a week or two ago. Today, we wiped the outside of the can as best we could and shifted it into the staging building. We did another cleaning inside, getting what we could out of the latches vacuuming as we went. We then opened the can and cleaned both sealing surfaces of the can, the oring seal and scrubbed the ISI platform multiple times with alcohol wipes. After lunch we wiped it down a final time, used a bit of steel wool to remove some stubborn stains on the bottom of the platform then moved the ISI onto the suspended platform. The ISI is held in place with 4 3/8-16 screws through the top of stage 0 and around 10 all thread studs threaded into the support platform. Lid flew back on and we are ready for the trip to the OSB. Randy moved the install fixture into the LVEA yesterday, so we just have to move the ISI, install cart and lifting bridle to the LVEA. Looking pretty good for ISI install Monday or Tuesday.

Visually the ETMY HWWD looks nominal, all power LEDs are green. To test I unplugged the top monitor connector and after a few seconds the LED-FAULT red led lit up. After 8 seconds I plugged the monitor connector back in which cleared the LED-FAULT light.

Attached trend shows the HWWD STAT go to 8 (led current fault) and the countdown timer started counting down from 20 minutes (seconds channel shown).

It appears there is no problem with the HWWD unit itself, and the change in behavior since the power outage must be related to something upstream (satellite amps). I'll pass this onto Fil for further testing.

At this point I'm not sure if the ETMY hardware watchdog system is fully functional, but bear in mind this is a secondary watchdog to the IOP SWWD.

Betsy, Camilla, Sheila, Tony, Robert

After Wednesday’s discovery that the PUM-level inter-chain stops would prevent us from overlaping the ITMY AR optical lever beam and the arm-cavity side CPY beam (overlapping these beams gives the correct orientation of CPY), we decided to back off the adjustment just a little to reduce the chance of touching and leave the beams closer than prior to the vent, though not overlapping.  At the end of Wednesday, the beams that were supposed to be overlapped were about 0.18 of the ITMY HR - ITMY AR spot distance. They were still at 0.18 Thursday morning and, after backing off a little, were at 0.22 of the HR-AR distance (with the same 0,0 slider settings they started out at 0.32).

These measurements were made with the R0 sliders at 0 pitch and 0 yaw. We also found the slider settings for the closest approach (see figure). At this closest approach the spots only differ by 0.085 of the HR-AR distance (3.4e-4 radians).

I calibrated the CPY sliders assuming the ITMY HR - ITMY AR spots were 4e-3 radians apart, due to the 0.08 degree wedge with assumed 1.45 index of refraction (coatings not considered). I get 0.63 microradians per slider unit in pitch and 0.69 in yaw. The calculated separation of the HR-AR spots, 4e-3 radians, was approximately equal to the measured separation, 3.8 e-3 radians, assuming we were 32 meters from the test mass.

I took transfer functions for ITMY's M0 and R0 to check for any rubbing that might have been caused by the negative pitch adjustment made to R0 (83865). Most importantly, we wanted to make sure that a negative pitch offset in the R0 OPTICALIGN OFFSET sliders wouldn't cause R0 to hit anything when driven. The negative pitch means that R0 is tilted away from M0, so the bottom of R0 juts towards the bottom of M0.

First I took a set of regular R0 transfer function measurements with the R0 offset sliders at 0. These look good.

I then set the R0 Pitch offset slider to -250, which we are unlikely to go past (typically that slider is set to mid +200s). We called this the 'closest approach'. I wasn't able to set the slider to its full offset of -440, because then the DAC range is so limited that we aren't able to drive it to take any measurements. These transfer functions also all look good. We especially made sure that Pitch was looking good and not rubbing anywhere.

To be even more certain that we weren't going to end up with anything touching, we ran a few transfer functions on M0 with a 'double closest approach' setup. With the R0 Pitch slider still set to -250, I changed the M0 Pitch slider to +250, tilting the bottom of M0 towards the bottom of R0, putting them even closer. I then checked Pitch, Vertical, and Yaw, with Pitch being the most important in telling us whether we were anywhere near close to having them hit anything. Those also all came back clean (Yaw looks weird but Jeff assured me that that's due to cross-coupling movement that went away when we reran it with damping loops on*).

We are confident that the adjustments made in the chamber didn't put us at risk of rubbing, and so doors are clear to go on. Once doors are back on we will check again.

These measurements have been committed to svn and can be found at:

.../QUAD/H1/ITMY/SAGR0/Data/2025-04-10_1800_H1SUSITMY_R0_WhiteNoise_{L,T,V,R,P,Y}_0p01to50Hz.xml         r12208

.../QUAD/H1/ITMY/SAGR0/Data/2025-04-10_2200_H1SUSITMY_R0_WhiteNoise_{L,T,V,R,P,Y}_0p01to50Hz.xml         r12208

.../QUAD/H1/ITMY/SAGM0/Data/2025-04-11_1600_H1SUSITMY_R0_WhiteNoise_{V,P,Y}_0p02to50Hz.xml               r12212         

Results have been committed to svn and can be found in:

.../QUAD/H1/ITMY/SAGR0/Results/2025-04-10_1800_H1SUSITMY_R0_ALL_TFs.pdf                      r12210

.../QUAD/H1/ITMY/SAGR0/Results/2025-04-10_2200_H1SUSITMY_R0_ALL_TFs.pdf                      r12210

* Full explanation from Jeff: "the 'weirdness' in yaw is the several frequency points where the reference looks smooth as a function of frequency between resonances, and the new data has 'lots' of single-data-point excursions from that smoothness. I attribute this to lack of coherence, and lots of motion on the QUAD. Yaw is a differential measurement of F2 and F3. We’re already having to drive less than normal because we have large offsets on. But also, we typically see that since there’s lots of motion, the imperfect calibration of the F2 and F3 sensors shows up, and lots of other DOF’s resonances show up at a low level where they shouldn’t. Turning on the damping loops and measuring again with them on is the confirming evidence that this is what’s going on. We took the same TF with the R0 and M0 chains damped and they look good."

Fri Apr 11 10:10:04 2025 INFO: Fill completed in 10min 1secs

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

Dew point measurement at YBM , approx. -42C

Attached is the Trello showing what has been achieved this week and what is on the books for today.  Many things started yesterday were (expectedly) not finished in 1 day so will roll to today, namely finishing feedthru (and some cable) population in the empty HAM1 chamber, and evaluating ITMY and it's reaction chain for closeout given the new CPY slight pitch change. The ISI is ~en route from the staging building to the LVEA ~today in prep for install early next week.  Things seem to be on schedule with how I had them laid out in the plan, even after the Monday schedule loss due to the gnarly power outage and EE component failures which took the vent staff all day to recover from.

TITLE: 04/11 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: 0.22 μm/s
QUICK SUMMARY:

Left over tasks from yesterday:

• ONGOING   BSC8 - ITMY and R0 TFs after alignment complet
• ONGOING HAM1 ISC prep - check all removed cables for loose screws
• ONGOING HAM1 ISC prep - Inspect Optics and beam dumps, FC if needed
• ONGOING  HAM1 ISC - rework M12 and M15
• HAM1 ISC prep - Recheck all RMs with FRS ticket issues
• JASON - IAS HAM1 support tube ends?

On the docket for today is:

BSC8 - Prep for Closeout

BSC8 - DOOR ON

HAM1 - Prep for ISI install

VAC Start Feedthru Swap

Today's activities:

• HAM1 feedthrus were installed according to D1002872-v10.  D6 is completely populated.  D1 was populated with everything except the feedthrus on the 5-way cross.  Those will be added in the next days.  The 3-port adapter (currently on D4 but destined for D3) has completed 1 of 2 feedthru swaps.  
• CP1 RGA is being revisited.

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           |