(Jordan V., Travis S., Gerardo M.)

The new purge air compressor, Kobelco KN-0, developed a very small leak a few weeks ago, it was first noted on 1/30/2026, I notified the vendor the same day.  About a week later they sent a technician over, the technician did diagnosis of the unit and determined that the unit was leaking oil.  The leak was located at the oil pump body, and after a conversation with his supervisor they decided to replace the pump "because some of them just leak from the start".  But they needed to order the pump and it was going to take a few weeks.  Also, due to an active vent, we decided to continue using the system as it was.  But, we did increased our visits to the unit to twice daily.

     This is an excerpt from the report regarding the leak: 
"INSPECTED UNIT AND DISCOVERED LEAKS OUT OF 3 DIFFERENT LOCATIONS IN 
THE OIL PUMP HOUSING. APPROXIMATELY 3-4 OUNCES OF OIL WAS IN THE 
BOTTOM OF THE CABINET, BUT NO ACTIVE DRIPS WERE VISIBLE. JUST RESIDUE 
ON SEAL LOCATIONS AND A PUDDLE DIRECTLY BELOW."

Fast forward to today (3/10/26), two technicians showed up to replace the oil pump, no issues were encountered during the replacement.  Due to the leak and the oil pump replacement the oil was a bit low, the technicians topped the unit with oil.

      This is an excerpt from the report regarding the oil pump replacement:
"TRIP 2: OIL PUMP REPLACEMENT ON ABOVE KNW 0. REMOVED OLD PUMP WITH 
LEAKING SHAFT, REMOVED FITTINGS AND PLACED FITTINGS ON NEW PUMP. 
REPLACED THE COUPLING AND ENSURED PROPER DISTANCE TO MOTOR 
COUPLING ELEMENT. TOPPED OFF OIL LEVEL.TIGHTENED ALL FITTINGS, HOSES 
AND BOLTS. TEST RAN UNIT FOR PROPER CYCLING AND LEAKS FOR 30 MINUTES.
TOOK READINGS - LEFT UNIT OFF."

The compressor is now off.  Closing WP-13081

Ryan C, Sheila, Jennie, Jenne, Camilla, Ryan S, Daniel

Ryan got the green arms locked and then Sheila and I went on ISCT1 to improve the COMM and DIFF beatnotes, to +2dB and -10dB.

Dave and Ryan fixed a ISC_LOCK Channel not found error. 

Sheila then aligned MITCH and started to check the phasing using 'ndscope sheila.dwyer/ndscope/LSC/phase_LSC_9_and_45.yaml'. Comparing to November, screenshot attached. First AS_A_RF45 was rephased after WFs were centered, needed +90deg. See sdf's attached. All LSC 45's were then phased following the same +90deg. Check REFL 9 with a swinging MICH and decided it was close enough. No LSC RF9's were changed. 

There were some pauses for JAC table work. 

Ryan then re-ran green initial alignment (wasn't done this AM), checked beatnotes were still fine. Jenne, Jennie and Sheila locked ALS and locked MICH. 

Sheila needed to revisit PRX alignment as struggling to find POP beams.

Jenne realized the mode cleaner isn't using DOF3, it used to feedback to the PZT, but now needs to feedback to JM3.

Daniel did the IMC phasing of WFs. 

Jennie W, Jenne D

We need to check the positions of IM1 and 2 as we have now closed all 3 loops for the IMC alignment.

Jenne was windering how our input alignment to the IFI compares to before the vent.

We compared the IM 1 and 2 pitch and yaw positions in manual initial alignment between today and the 12th of December - when we were doing our last locking before the vent.

This comparison is during manual initial alignment which is state 8 in the ISC_LOCK guardian.

The first pic is the 12th December, reference time is 05:21:30 UTC.

The second pic shows today with y cursors at the reference values. The biggest difference is IM2 pitch which is ~120 counts lowewr than it was, the other 2 DOFs are tens of counts off.

I also included IM3 and 4 in my plots but I think we have intentionally changed IM3 since the vent to improve alignment onto IM4 trans and IM4 is controlled.

TITLE: 03/10 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: Tony
SHIFT SUMMARY: Alignment work today, green arms, Xarm IR, MICH, PRX alignment is being worked on as of the end of day shift.
LOG:                                                                                                                                                                     

• 16:00 TEST T629846
• Sheila and Camilla went out to ISCT1 and fixed up the ALS beatnotes, DIFF went from ~ -12.0 -> ~ -10.0, and COMM went from ~ -33 to ~ +3.0.
• Sheila unlocked the PSL rotation stage, I turned up the power to 2Ws, Sheila left the PSL rotation stage unlocked.
• 18:41 UTC I restarted standdown_alerts
• 18:48 UTC Firepump testing, 1 & 2
• JAC team encounted an issue regarding a missing cable for the JAC PD shutter
• 20:00 UTC We started to work on the XARM IR alignment
• 20:26 UTC We ramped up to 10Ws for MICH
• The Optics Lab will have a laser running unattended overnight like yesterday, the signs will be put up when people are done working in that lab and the laser is shuttered.

Jenne Driggers, Jennie Wright, Sheila, Ryan Short, Ryan Crouch, Tony

We are running all three IMC ASC DOFs.  Jenne turned on DOF3 pitch without issue once she set up the feedback through JM3.  The YAW DOF was unstable, we checked the output matrix for yaw.  With the gain increased on DOF1+DOF2 we put 10 couns on JM3 pitch test, and measured the responses on MC1, MC2, MC3 outputs from the IMC ASC.  (screenshot attached).  We scaled these responses to give us the new output matrix, this worked well once we flipped the sign.  We accepted these changes in SDF so they should be used everytime the IMC locks from now on. 

In the process we remembered that IMC ASC has the intergrators in the asc model, not the suspensions. 

Turned laser on first thing and Marc turned on the SQZ High Voltage in the Mech room mezzanine 89449, the PMC and SHG looked without issue. I turned back on the SFI1, SFIO2 and OPO TEC servos (were turned off for venting).

Segment 3 of H1:SQZ-RLF_QPD_A_SEG_3 is broken 89020, so we will need to decide what to do about that but I didn't do anything yet. 

Increased SEED light from 0.5mW to 75mW, then LOCKED_SEED_DITHER, power was then 0.1 mW on SQZT7, previously ~2mW. Checked QPD B, power now 13nW, previously 130nW, for similar CLF_TRIG reflected power. see attached. Can try to realign via QPD_B and ZM2,3 but have not yet done this. 

Changed OPO temp from 31.72 to 33.703 while injecting CLF and scanning the OPO PZT to coalign green and IR peak (Sheila said SEED may have been quicker).

OPO with CLF still didn't lock. With H1:SQZ-OPO_PZT_1_SCAN_TRIGGER_CHANNEL_1_LEVEL and 2_LEVEL reduced from 0.5 to 0.1 and it debatably locked looking at  H1:SQZ-OPO_IR_RESONANCE_CLF_RF but with no signal on H1:SQZ-OPO_IR_PD_DC_POWERMON... maybe the alignment is just very bad.

Pausing here. 

I was looking at the correlated spectra of the IMC WFS segments and minimizing the q-signals.

Attached: screenshot of new values and spectra.

With the new EOM we used a single bounce scan of the OMC to measure the modulation depths of the 9 and 45 MHZ signals as we will need them to lock the IFO now we have the IMC lock working.

Old values:                                New values:

gamm9 = 0.213                        gamma9 = 0.235

gamma45 = 0.275                    gamma45 = 0.285

For a reference for the old measurements see this alog from Elenna (#81816) and this alog from me for new ones (#89230).

PSL Weekly Status Famis 39755

Laser Status:
    NPRO output power is 1.824W
    AMP1 output power is 70.51W
    AMP2 output power is 138.9W
    NPRO watchdog is GREEN
    AMP1 watchdog is GREEN
    AMP2 watchdog is GREEN
    PDWD watchdog is GREEN

PMC:
    It has been locked 3 days, 21 hr 16 minutes
    Reflected power = 26.77W
    Transmitted power = 104.3W
    PowerSum = 131.1W

FSS:
    It has been locked for 0 days 0 hr and 52 min
    TPD[V] = 0.4982V

ISS:
    The diffracted power is around 3.9%
    Last saturation event was 0 days 12 hours and 57 minutes ago

Possible Issues:
    PMC reflected power is high

Tue Mar 10 10:07:31 2026 INFO: Fill completed in 7min 28secs

I inspected the IO chassis and AI chassis in all four racks and noted the following:

SUS-C1
U30-U31 AI chassis pair, these chassis were configured for clip style scsi cables, but screw style were installed.  This should be changed when we vent in 2 weeks.

SUS-C2
H1SUSAUXB2H34 - All jack screws are installed, all cables are secure.
H1SUSB2H34 - All jack screws are installed, all cables are secure.

SUS-C3
H1SUSH2AUX - All jack screws are installed, all cables are secure.
H1SUSH12 - All jack screws are installed, all cables are secure.

SUS-C4
U29-U30 AI chassis pair, these chassis were configured for clip style scsi cables, but screw style were installed.  This should be changed when we vent in 2 weeks.

There are no remaining critical issues at this time, so closing WP12079

We turned on the HV for SQZ.  The power is located in the racks on the Mezannine in the Mechanical Room.

We followed Fil's instruction by first turning on the 24V for the interlock chassis, then ensuring the bypass was removed, sensor plugged in, and pressing the red reset button.

Then we switched on the SQZ_PZT and the SQZ_TTFSS power.

M. Pirello, C. Compton, S. Muusse

Turned on SQZ laser, CO2 lasers and TCS Sleds. All came on fine. 

TITLE: 03/10 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: CALM
    Wind: 4mph Gusts, 2mph 3min avg
    Primary useism: 0.05 μm/s
    Secondary useism: 0.29 μm/s 
QUICK SUMMARY:

• More alignment and commissioning plans for today
  • Phasing work then DRMI!

Workstations were updated and rebooted.  This was an OS packages update.  Conda packages were not updated.

TITLE: 03/09 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:

IMC was locked by sheila/camilla/ryanS.  Checks on the BS & PR3 pointing were made.  All is set for phasing work out on the floor tomorrow and then moving on to DRMI locking.
LOG:

• 2316 Jeff out of optics lab (NPRO still ON, shuttered CLOSED, laser curtain will be closed OVERNIGHT---Oli is still in there and will leave it as so).
• After Oli was done with BHD work, the chain & sign were put in place for "laser running unattended" overnight.

Sheila, Ryan C, Ryan S, Marc, Daniel, Oli, Control Room...

During the morning, Sheila and Ryan struggled again with the IMC locking. Lots of trending and adjusting gains and signs. The IMC OLG looked noisy and the IMC could stay locked for ~1minute without SUS feedback but not with feedback. The MC1 DAC card was swapped 89426, 89427 and new transfer functions showed this was better than Friday 89435,  however IMC still wouldn't stay locked. Daniel, Ryan and Sheila then realized that MC2 M2 was not actuating and Marc and Oli tracked this down to a loose cable 89434, 89436. Oli opened FRS ticket: 37180.

After this was fixed, Sheila started editing the guardian to remove temporary fixes and remeasured the IMC OLG, see attached. This now looks good, 38.5kHz UGF is with 2W into the IMC, gain 5, one common boost on, which is as old guardian would have set it, except M1 feedback is still off. This was compared to 89046 Feb measurements. IM4 trans is 1.2W which is a little lower than before the JAC install. 

After the VAC team decoupled the AUX carts by HAM1/2, Jim unlocked the HAM2 HEPI. 

Ryan C locked the green arms using INTIAL_ALIGNMENT_OFFLOAD as Jenne reset those references last week 89385.

After HAM2 was unlocked, we struggled to turn on the MC2 M2 feedback, however the IMC was surprisingly stable with only the M3 and laser feedback, Sheila took IMC-MCL crossovers. It's a strange loop as M2 isn't really doing anything so Sheila tried copying the PRCL M2 filters over to actuate via M1, this didn't work. 

Sheila turned on the IMC WFS, this worked well and brought IMC_TRANS from 180 to 200. Then they were offloaded using the guardian (not the smoothest offloading). After the WFS were offloaded, we reset the guardian to include both M1 and M2 feedback and it worked.

The IMC-MCL crossover was re-measured to be on it's reference, see attached. 

[Jenne, Corey, RyanS, Jane Glanzer]

After EE fininished cabling ISCT1 and IOT1, Keita and I put up laser barriers to make the South Bay of the LVEA local laser hazard ("bifurcated"), so that both tables can be opened at will.  

Please pay attention to the signs on the laser barriers, and if the barriers are closed and / or the signs show Hazard, then wear laser safety goggles beyond the barriers.

The Vac team opened the gate valves, and we ran the baffle align scripts.  After the baffle align scripts completed, I did not touch ITMX again.  

Corey and I moved PR3 so that we could see beams on the cameras (we later reverted PR3's sliders), and moved ETMX and TMSX until we had nice TEM00 flashes.  We were then able to lock it and run then offload the ETM_TMS_WFS.  

With Xarm nicely aligned and PR3's sliders reverted, we had great transmission on ALSX and a familiar looking spot on the camera.  However we didn't see anything on the Yarm PD or camera.  So, I moved the BS until I could see something (also having increased the exposure of the camera so we could see the straight leakage beam), and then moved ETMY until we started to get flashes.  I aligned ETMY and TMSY until we could hold lock on TEM00, and moved the BS until we had ~max transmission on ALSY's transmission PD.  We then ran then offload the yarm's ETM_TMS_WFS. 

I then (since HAM1 is at much lower pressure than 10 mTorr) opened up the ALS light pipe, and went to check that the alignment on the table looked "reasonable".  Indeed, it looks reasonable, in that the PSL beam seems to go nicely through the SHG and is roughly centered on downstream optics.  However, we don't have good beatnotes.  I had a quick look at the beams headed toward the beatnote PDs, and at least one is easy to see that there are 2 distinct beams headed toward the PD.  I don't recall on the top of my head if this is the Diff beatnote though; if it is, then it depends on the BS alignment, so we likely want to hold off on doing any on-table alignment until we have a better idea of the BS alignment relative to the ITMs. 

At Sheila's suggestion, I also reset the green initial alignment references (SDF table attached just before accepting them), so that we have an easier time coming back to where we are now.  As usual, we'll have to re-reset them after we achieve full 2W lock.

In summary: ITMs were set with the BafflePD script.  Green ETM_TMS WFS were run and offloaded.  Nothing on IST1 was touched (yet), but it's clear that we'll likely need to do some on-table alignment.

Proposed next steps: Check BS alignment by looking at MICH (so, after JAC is locked, then IMC locked, then XarmIR aligned).  Then, consider aligning the ISTC1 beatnotes.  Then, lock the whole IFO!