Julia, Georgia, Sheila, Camilla, Elenna

This might be out of date already as some ASC input matrices have already been updated.

On Sunday we had some locklosses as we powered up from a 0.02Hz oscillation. One known issue is we have taken out some gain out of our CHARD loops. We wanted to check our sensing (input) matrices CHARD, INP1 (which both use the refl wfs) and PRC2 (which uses new in vac pop_x).

We sat at 10W, with the input matrix Sheila found last week:

While Elenna measured the phasing using an 8 Hz line, Julia and I added offsets into the loops and looked at the responses in the different sensors.

• When we stepped INP1_P, we saw a differential response in REFL_A and REFL_B RF45 (first screenshot)
• When we stepped INP1_Y, we saw a small common response in REFL_A and REFL_B RF45 (second screenshot), and maybe a small response in RF9 (which is what was in loop)
• When we stepped CHARD_P, we saw a differential response in REFL_A and REFL_B RF45, same as INP1_P (third screenshot) and a small response in REFL_A and REFL_B RF9 in the Q quadrature (sad)
• When we stepped CHARD_Y, we saw a small differential response in REFL_A and REFL_B RF45 and perhaps also in RF9 (fourth screenshot)
• When we stepped PRC2_P, we saw a differential response in REFL_A and REFL_B RF45, RF9, and a step in POP_X (a bit weak?) (fifth screenshot)
• When we stepped PRC2_Y, saw saw a strong response in REFL_A and REFL_B RF9, and POP_X (fifth screenshot)

Some of this is a bit different to what Sheila saw last week, but our ifo alignment has changed. We want to find intrixes that are sensitive to each DOF and ideally are insensitive to the other DOFs.

• It seems like RF9 is not a good sensor of INP1
• For some reason our steps showed a similar repsonse in A and B RF45 to INP1 and CHARD in P, which was the opposite of what Elenna saw in her radar plots?
• POP_X is good at only sensing PRC2, but PRC2 yaw shows up in other sensors...

While writing this another input matrix for INP and CHARD has been put in - https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=84711 - and seems to be working so stay tuned.

We plan to work on our gain heirarchy and hopefully power up further soon!

Addressed TCS Chillers (Mon [Jun2] 100-125am local) & CLOSED FAMIS #27816:

• TCSx Chiller:  Had level of 29.6 cm.  Added 300mL for 30.4cm.
• TCSy Chiller:  Had level of 9.6 cm.  Added 280mL for 10.3cm.  
• There was no water in the small cup under the slow leak.

This morning while Corey and the commissioning team were trying to lock and power up the interferometer, the violin modes were pretty rung up. For most of the modes, I was able to damp them down using nominal settings except three of them which are listed below along with the settings which seems to be working for now. 

• ITMx mode 3 - FM1+FM9+FM10 Gain = -20 (+60 deg phase)
• ETMY mode 1 - FM1+FM6+FM8+FM10 Gain= -0.1
• ITMY mode 05 and 06 - FM6+FM7+FM10 Gain = +0.01 (-30 deg phase)

FAMIS 31088

No major events of note. The slow changes in PMC TRANS and REFL power seem to follow AMP2 output power.

TJ, Camilla, Checking as Sheila was concerned about this as Georgia/Craig need to move the ITMX SPOT GAIN "CENTER" 84702.

Attached are the HWS Live plots comparing when we get to 10W and 120s later for ITMX and ITMY now. And also for ITMX and ITMY at our last 10W power up before the vent (note that then we don't pause at 10W and continue increasing power during the 120s). 

Can see no obvious new point absorbers, ITMY looks perfect and ITMX has the same point absorbers as before, it;s possible there's a new point absorber on the right of the optics (orange arrow in attached) but it doesn't look scary. We will continue to check this but it's possible that our alignment has just changed (has since 66198) so that we can now see this point.

HAM1 annulus system appears to have issues pumping down, currently its annulus ion pump is railed 10 mA, and the pump cart pumping on this system is sitting at 6.04x10^-05 Torr, see attached photo.

Process thus far:

• Last Thursday I managed to go and visit some of the -Y door bolts, found out that most of the bolts from 3 to 7 O'clock were not tigth, I was able to get 90 degrees turn, one bolt was actually loose, I was able to turn it by hand, but those were the only one that I was able to work on, since I was asked to stop work at HAM1.
• Another test done was to check for leaks on the aux cart pumping line, so the cart was isolated via the annulus system isolation valve, the pressure dropped at the aux cart down to 4x10^-06 Torr, meaning that no leak is on the pumping side, the isolation valve was opened again to continue pumping.

I plan to visit HAM1 to check the rest of the bolts on -Y door and +Y door.

Mon Jun 02 10:12:16 2025 INFO: Fill completed in 12min 13secs

Gerardo confirmed a good fill curbside.

M. Todd, C. Cahillane

Yesterday we were interested in some noise we were seeing around 6Hz in various ASC signals (mostly CHARD pitch). This motivated us to look at the RMs, so I took a PSD of each DOF for both RMs.  We are not sure why there are such differences in all the dofs, and if there are unintended side-effects to this.

I'm specifically wondering why RM2 has larger peaks around 6.25 Hz in all dofs...

Camilla, TJ

Sheila asked us to look for post vent point absorbers, but when we went to check, we found that the code hadn't been running since May 23rd.

Looking further into it, we could log into the machines and open the tmux sessions, but the code was frozen from May 23 821UTC and could not be Control C'd. I then tried a pkill on that python process, this also did not work. Trying to reboot the machines remotely aslo didn't work. I power cycled the machines from the MSR, then we were finally able to start the code up. ITMX needed the camera initialized for some reason.

We are thinking about ways to catch this in the future, maybe having DIAG_MAIN monitoring if values are updating properyly.

TITLE: 06/02 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 15mph Gusts, 8mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.22 μm/s
QUICK SUMMARY:

H1 was down for the night, so will most likely run an alignment and then go for Power 10W and then assess.

• Edit#1:  While dropping off some yogurt in the fridge I came back to ALS_YARM in a STALLED state (which appears to be a norm as of late).  Rerequested INITIAL ALIGNMENT and it was fine.)
• Edit#2:  Also had Stalls while trying to get to PRX_LOCKED, but TJ arrived and I let him know about this and he mentioned this is because we are doing MANUAL ALIGNMENTS (this won't happen when we return to our usual Initial Alignments)

TITLE: 06/02 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: TJ
SHIFT SUMMARY:

IFO is in DOWN and in PLANNED ENGINEERING

Productive day in which we made it past 25W before a violin-mode gain related lockloss.

The lockloss kicked our alignment so I did a manual initial alignment, which worked to lock DRMI. We can now semi-reliably get to powerup automatically. The goal now is to continue powering up while monitoring IFO status.

For details, check out alog 84706, alog 84702

LOG:

Just a brief note on the CHARD P error signal.
When fitting an excitation for injection, I noticed a large peak at 6 Hz that I hadn't seen previously.  
I'm guessing it's from RM damping but I'm not 100% sure.

I went back to a NOMINAL_LOW_NOISE time from last March 12, 2025, to compare what we had before.  
There seems to be a number of differences.

There's some large broad peak around 16 Hz in March 12 that's no longer there now.
I checked a couple of times in that March 12 lock at this broad 16 Hz lump is always there.

The 6 Hz peak is much larger now, but there appears to be a small peak there even in March.

Not sure the causes of such differences, but someone who knows more about the HAM1 changes could have better insight, especially related to the ISI upgrade and status of the RMs.
The comparison is not fair either, since we are only at high noise, 20 W of input power now for June 01, whereas in March we had NLN and full power.

 

Closes FAMIS 26455. Last checked in alog 84145

Trends are within red error lines. Seems that there were 3 spikes week of 05-11 to 05-18 which can probably be attributed to vent work, but I am unsure.

Closes FAMIS 26386 and FAMIS 26384 and FAMIS . Last checked in alog 84405,

Everything is under threshold. Took 2 weeks since was undone for the week prior.

Corey, Ibrahim, Georgia, Craig, Matt, Caroline, Julia

Corey locked the interferometer after the earthquake.
We were pretty much able to go directly to CHECK_VIOLINS_BEFORE_POWERUP without touching anything.  
Corey did tidy up the 2f signals by adjusting PRM and SRM alignment after DRMI locked, but the other guardian states "just worked" after our changes from last week.

We went up to POWER_10W, no problems there.
Then we started stepping through POWER_25W.
We ended up losing lock after upping the ADS gain from 1 to 2.

It was a very slow lockloss, which seems consistent with this story about it being ADS-driven.
We also had just turned on the SOFT Y loops to high gain (20 for CSOFT Y, 30 for DSOFT Y).
Georgia looked at the ADS control signals and it appears to be the PIT loops which killed the lock.

The above lock was with the ITMX SPOT GAIN at it's new "CENTER" value of -1.25, rather than 0.85.
We figured that since we MOVE_SPOTS soon after anyways, we can focus our efforts on trying to get up to high power with ASC relatively stable.

EDIT: We lost lock after going up to POWER_25W from what was probably that same very slow 0.02 Hz oscillation.  See picture 2.
Leaving the ADS pitch loops on at only a gain of 1 was not good enough.

Georgia added back in +10 dB to both PIT3 and YAW3 for the ADS which was commented out a few days ago while we were sitting at 2W CHECK_VIOLINS_BEFORE_POWERUP.  
This caused a lockloss when going up to POWER_10W.
This indicates it's just ADS PIT3 which is the major problem here.

EDIT2: We are sitting here at 20 W of input power, measuring CHARD P for an hour.  
We turned off ADS PIT3 while going up in power, with the plan of trying to ease it on at lower gain. 
While we were sitting here measuring, the 0.02 Hz oscillation came back.
Georgia stopped it by lowering the PIT4 and PIT5 gains from 1 to 0.1.

EDIT3: We tried to MOVE_SPOTS, but lost lock after about 8 minutes due to a violin mode damping typo.  
Georgia lowered the ADS gains to 0.1 for all, including PIT3 starting at the weird spot position on IX.
The buildups were getting very choppy, but we were surviving.  Unclear how far we could have made it.
Julia was damping violin modes and accidentally typed in -20000 into a filter module gain, which seems to have immediately saturated the IX PUM stage and killed the lock.
This is Julia's first lockloss so we will be nice to her this time.

Changed the DARM_OFFSET ISC_LOCK state number to be in order, after ENGAGE_ASC_FOR_FULL_IFO

For chamber closeout finalization, this morning I 

* placed a 3" contam control wafer on the center of the HAM1 table today
* took a few last pics, removed the stowed 3x septum covers (missed removing the 4th one from the septum, thanks vac good eye, pic 4)
* looked around for left behind tools
* retraced the beam path to look for errand in-the-way cables (none observed)
* inspected under and around lower area of table for left goods (none found)
* cleaned up last tool pans to get ready for doors
* particle counts were <50 all sizes, zero most often
* purposefully coiled the to-be-used in post O4 next vent cable with the peek connector not grounding to anything - it sits in the PSL side door well below the table

* all subsytems have signed for doors, so we are putting doors on.

Keita, Elenna, Oli, Rahul, Camilla

Summary: Majority of REFL path optics are aligned. Need to beam profile and finish LSC and ASC REFL diode placement on this path and place/check all beam dumps.

This morning, Keita opened the light pipe, locked the IMC  but couldn't see the beam as nicely as he did on AS_AIR yesterday. Since that time he had restored PR2 and PR3 to a time we were last locked. He reverted those changes as we could see the beam back at AS_AIR. Checked again IM4 trans QPD was the same as yesterday.

• The beam coming out of the spectrum port was not centered on the REFL optics that had been placed as per D1000313-v19. We checked Corey's photos to compare REFL optics position relative to periscope and the D10002313 drawing and convince ourselves the beam in correct just the drawing of it is incorrect.
• Firstly checked the incoming beam was centered on M14 and the reflected beam off this was dumped on the HiPWR beam dump which was moved to it's final position.
• Beam centered on HW1
• Beam centered on M17 and the reflected beam off this was dumped on the HiPWR beam dump
• Beam centered on M1 and headed towards M2
• Beam centered on M7, following the correct beam path off the table and dumped but a temporary dump (before we put in BDV1)
• Beam centered on M2 and headed towards center of RM1.
  • Transmitted M2 beam dumped by BD8
• Rahul got RM1 and RM2 damping loops working so they are now in DAMPED nominally (changed OPS whiteboard) Rahul set sliders to zero.
• Beam centered on RM1 and headed towards center of RM2 (we had to turn RM1 in YAW)
  • BD16 placed behind RM1 but beam can't be seen to align to.
• Placed M5 in roughly correct place
• Beam centered on RM2 and headed towards center of M5 (we had to turn RM2 in YAW)
• Beam centered on M5 and headed towards the SLED
  • There was a fair bit of iteration of M2 and M5 here to get the beam to be aligned and centered on all optics through the SLED, still needed to adjust SLED mirror to get it centered on the final mirror.
• Adjusted the SLED steering mirror (in the position +X -Y) on the SLED to center the beam on the ASC REFL B diode steering mirror.
• Adjusted ASC REFL B diode steering mirror so that picomotors had some range left.
• Beam centered on M6 and headed towards L1/M18
• Beam centered on L1
• Beam centered on M18 and headed towards LSC REFL A and LSC REFL B
  • We stopped here before fully aligning these too diodes
  • LSC REFL A is aligned by eye and 22cm from L1 (+222mm FL)
  • LSC REFL B is 20cm from L1 and will be moved to match LSC REFL A tomorrow.

Additionally M16 was placed roughly in the correct position, all optics are now on HAM1 (apart from PM1) and the class-B pans are empty and packed up.

Left IMC locked.