Sat Feb 21 10:11:00 2026 INFO: Fill completed in 10min 56secs

When checking the Kobelco unit this afternoon, I found there was a standing puddle of water (~1/4in deep) on the right side (looking at control screen) of the enclosure. Moving to the back side it was found to be a leak in the aftercooler auto drain line, right at the isolation ball valve. There was a continuous spray of water coming from the threads on the upstream side of the ball valve.

The dewpoint at the drying towers was still -81C, same value as this morning, so it did not cause any issues downstream of the compressed air line. The drained water was simply collecting in the bottom of the enclosure instead of flowing out of the drain line.

There was no in-chamber work happening at HAM1 at the time of discovery so after a phone call with Gerardo, I shut down the compressor unit and isolated the air line between the compressor and the receiving tank. I then closed the purge air inlet valve at the HAM1 chamber.

There is currently no purge air going to the LVEA.

Jennie W, Keita K, Rahul K, Ryan S,

This morning Keita turned the power up to 1 W and the purge air down in order to scan the OMC and measure the modulation index.

We had some work to do to lock the JAC, the cavity wouldn't scan properly when managed by the guardian code.

Ryan and I have looked back at it and think there may be something wrong with the feedback to the PZT. It can't be the PZT itself though, because Keita and I were able to lock on the TRANS PD signal with the dither locking done manually by tuning the PZT offset to find the resonance and then turning on the feedback.

I have enclosed a picture to aid problem solving next week.

We then had problems keeping the IMC locked so Keita had to change the threshold used to check if the cavity is locked down to 2. This was changed at line 133 in ISC_library.py at userapps/h1/isc/guardian/.

trans_pd_lock_threshold = 2

We then managed to do three scans,

one with 45 MHz off, one with both on, and one with 9 MHz off. Detailed analysis in progress.

After turning the power back down Keita and Rahul swapped the mirror we currently have in front of the TRANS PD, with the uncoated laser window that is meant to be there (JACT_BS1).

They had to top gun and swab it to remove two dust particles first.

This replacement means the power to the PD is lower and so we needed to power up to 1W to check this alignment.

I have left the mirror we took out on the table on the -Y side labelled as 'HR mirror taken out of JACT-BS1'. Need to check which exact mirror this is with Masayuki on Monday.

Keita locked the cavity manually with the REFL PD and optimised the amount of light falling onto the TRANS PD.

I powered down to 100mW and de-energised the rotation stage and closed the light pipe at the end of the day. We also had the rotation stage de-energised and locked out when we were working in chamber.

Modulation index measurement for 45M and 9M, they're healthy.

1W into JAC, no WFS for IMC, ITMY single bounce. Scanned OMC with both 45MHz minimal power (~4dBm) and 9MHz full (~27dBm), then both in full power, then only 45MHz in full (see screen shot).

Jennie will post the modulation index later, but the peaks look healthy to me.

The alignment into IMC was rather off in PIT and the guardian had a hard time locking IMC (I changed the lock threshold in the guardian). We didn't move MC, didn't bother to do any thorough investigation, but either JAC or MC mirrors moved. Maybe we have to lock IMC, use WFS for MC, and steer JM3 and see if the MC mirrors will be driven far from where they are. If they are we might have to touch up in-chamber alignment again.

JAC TRANS BS was swapped with the real one (laser window with AR only on one surface).

We replaced the JAC TRANS BS (which was a temporary high reflector until today) with the real one that is just a bare glass (the reflectivity is 7% or so depending on AOI). 

We locked JAC with RF, was able to see the beam coming to the TRANS PD but wasn't able to see the reflection of PD, so we raised the power to 1W.

Initially the beam was missing the PD because the new optic is thinner than the temporary one. We realigned the optic to steer the beam back to PD. Since we could not directly see the PD surface, we just steered the beam up and down, left and right until the PD output starts to drop, and put the beam roughly in the middle.

We were able to see the PD reflection using an IR card and an IR viewer. There were two reflection blobs (which was the case before, too),  and I moved the JAC TRANS BD in +X direction by 1/4~3/8" to catch both.

TITLE: 02/20 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:

IFO is in IDLE for PLANNED MAINTENANCE

Calm day. HAM1 work continued.

LOG:

Famis 39976 Inspect quarterly trends of HWWD bits for indication of negative function. 

All traces have had some motion on it in the last 91 days.

Yesterday afternoon I glued prisms to the LO2 optic for HRTS - see pictures attached.

This optic (D2100495-V5-LO2-M1-0002) will be shipped to LLO.

Famis 38888 SEI seismometer mass position check - Monthly :

Checking T240
Checking STS
Finished
Averaging Mass Centering channels for 10 [sec] ...
2026-02-20 11:36:02.279522

There are 12 T240 proof masses out of range ( > 0.3 [V] )!
ETMX T240 2 DOF X/U = -1.716 [V]
ETMX T240 2 DOF Y/V = -1.819 [V]
ETMX T240 2 DOF Z/W = -0.998 [V]
ITMX T240 1 DOF X/U = -2.377 [V]
ITMX T240 1 DOF Z/W = 0.459 [V]
ITMX T240 3 DOF X/U = -2.547 [V]
ITMY T240 3 DOF X/U = -1.089 [V]
ITMY T240 3 DOF Z/W = -3.077 [V]
BS T240 2 DOF Z/W = 0.346 [V]
BS T240 3 DOF X/U = -0.518 [V]
HAM8 1 DOF Y/V = -0.428 [V]
HAM8 1 DOF Z/W = -0.728 [V]

All other proof masses are within range ( < 0.3 [V] ):
ETMX T240 1 DOF X/U = -0.006 [V]
ETMX T240 1 DOF Y/V = -0.037 [V]
ETMX T240 1 DOF Z/W = -0.03 [V]
ETMX T240 3 DOF X/U = -0.024 [V]
ETMX T240 3 DOF Y/V = -0.07 [V]
ETMX T240 3 DOF Z/W = -0.043 [V]
ETMY T240 1 DOF X/U = 0.057 [V]
ETMY T240 1 DOF Y/V = 0.198 [V]
ETMY T240 1 DOF Z/W = 0.253 [V]
ETMY T240 2 DOF X/U = -0.087 [V]
ETMY T240 2 DOF Y/V = 0.215 [V]
ETMY T240 2 DOF Z/W = 0.046 [V]
ETMY T240 3 DOF X/U = 0.268 [V]
ETMY T240 3 DOF Y/V = 0.085 [V]
ETMY T240 3 DOF Z/W = 0.136 [V]
ITMX T240 1 DOF Y/V = 0.289 [V]
ITMX T240 2 DOF X/U = 0.131 [V]
ITMX T240 2 DOF Y/V = 0.257 [V]
ITMX T240 2 DOF Z/W = 0.242 [V]
ITMX T240 3 DOF Y/V = 0.119 [V]
ITMX T240 3 DOF Z/W = 0.061 [V]
ITMY T240 1 DOF X/U = 0.062 [V]
ITMY T240 1 DOF Y/V = 0.159 [V]
ITMY T240 1 DOF Z/W = 0.027 [V]
ITMY T240 2 DOF X/U = 0.021 [V]
ITMY T240 2 DOF Y/V = 0.243 [V]
ITMY T240 2 DOF Z/W = 0.16 [V]
ITMY T240 3 DOF Y/V = 0.082 [V]
BS T240 1 DOF X/U = 0.261 [V]
BS T240 1 DOF Y/V = -0.212 [V]
BS T240 1 DOF Z/W = -0.179 [V]
BS T240 2 DOF X/U = 0.142 [V]
BS T240 2 DOF Y/V = -0.271 [V]
BS T240 3 DOF Y/V = 0.061 [V]
BS T240 3 DOF Z/W = -0.263 [V]
HAM8 1 DOF X/U = -0.3 [V]

Assessment complete.
Averaging Mass Centering channels for 10 [sec] ...

2026-02-20 11:36:14.268587
There are 2 STS proof masses out of range ( > 2.0 [V] )!
STS EY DOF X/U = -4.582 [V]
STS EY DOF Z/W = 2.384 [V]

All other proof masses are within range ( < 2.0 [V] ):
STS A DOF X/U = -0.51 [V]
STS A DOF Y/V = -0.798 [V]
STS A DOF Z/W = -0.581 [V]
STS B DOF X/U = 0.108 [V]
STS B DOF Y/V = 0.953 [V]
STS B DOF Z/W = -0.309 [V]
STS C DOF X/U = -0.871 [V]
STS C DOF Y/V = 0.868 [V]
STS C DOF Z/W = 0.593 [V]
STS EX DOF X/U = 0.507 [V]
STS EX DOF Y/V = -0.551 [V]
STS EX DOF Z/W = -0.392 [V]
STS EY DOF Y/V = 1.204 [V]
STS FC DOF X/U = 0.153 [V]
STS FC DOF Y/V = -1.174 [V]
STS FC DOF Z/W = 0.637 [V]

Assessment complete.
Results copied to clipboard

Fri Feb 20 10:13:20 2026 INFO: Fill completed in 13min 17secs

The slow controls software was updated to include the ChetaX  electronics. The chassis is currently in the MSR for test purposes, but will be moved to the cheta lab next week.

Channels are located under H1:AWC-ITMX.

TITLE: 02/20 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: None
CURRENT ENVIRONMENT:
    SEI_ENV state: MAINTENANCE
    Wind: 14mph Gusts, 10mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.21 μm/s 
QUICK SUMMARY:

IFO is IDLE for PLANNED MAINTENANCE

JAC/HAM1 work continues

At 17:26 Thursday 19feb2026 h1iopiscex had a timing glitch causing a TIM+ADC error in its state word.

At 20:00 I restarted all the models which cleared the error.

Beam dump for HAM1-HAM2 septum window AR reflection.

This was installed. 

Beam dump for the -Y door viewport reflection.

Jason and Betsy installed it. There seems to be a discussion as to whether or not something else needs to be done.

EOM and JAC power budget again.

We measured the power at various places. While Jason held the power meter head still, I ran the statistics function of the power meter for a few seconds. I only list the mean and the standard deviation.

Wrong pol is king of large, ~0.2% of the main beam power coming out of EOM. That's 200mW when 100W goes through the EOM. 

JAC throughput of 92% is not great, but Jason says the alignment and the matching are not really optimised.

Rahul, Jeff, Oli

In December 2025 when we needed to compensate for the HAM1 DACs moving from 16- to 28-bit, we had decided to have FM10 in the COILOUTF bank be gain(1024), and put the remaining gain(4) upstream in multiple other places (88553). This led to our confusion today when we realized that when taking transfer functions for PM1 and JM3, the TEST banks had gone back to gains of 1 a couple weeks ago, and since we had damping off, the extra gain wasn't going through to the excitation. This might at least partially be why PM1 had dropped in magnitude, and why the JMs are so low in magnitude too.

To solve confusion, I've gone through PM1, RM1, RM2, JM1, and JM3 and removed the extra gain(4) that's in:
- DAMP bank FM4
- TEST bank gains (if still there)
- OPTICALIGN gains
- LOCK filter bank gains
Then I updated the gains in COILOUTF FM10 from gain(1024) to gain(4096).

I've sdf'd the values and loaded in the changed filter modules. I also committed the filter file.

*To remove future confusion about the difference in value of the "28BitDAC" filter module in COILOUTF FM10, I am going to go through all the suspensions and change the name of that filter from "28BitDAC" to be something like "16to28Bit" or "18to28Bit" depending on the previously used DAC bits

DAQ was restarted around 12:02 PM  PST after restarting h1ascimc. 

Jennie W, Ryan S

Summary: Ryan and I updated the JAC and IMC ASC models. We installed JM3 yesterday and so now the IMC cannot use the PSL PZT mirror as an alignment actuator. I have committed the changes to the svn but erik and dave will do some checks tomorrow before they commit to the revision locked version of the model and restart the DAQ. So changes are not 'live' yet.

The edits were made to h1ascimc.mdl which has top level blocks for IMC and JAC.

The JAC top level model sends signals directly to the PSL PZT mirror and these degrees of freedom are swapped as the PSL PZT basis P and Y are switched before input to the JAC due to the HAM1 input periscope.

I took out the feedback paths for PZT_P and PZT_Y that come out of the IMC block. The picture shows the old config and I have highlighted what I removed.

At the top level, IMC no longer sends signals to the PZT but instead to JM3. On the top level diagram, the signal JM3_P is sent via PCI cards to the channel "H1ASC-JM3_YAW_SUSHTTS" as pitch in the JAC basis is yaw in the IMC basis due to the HAM1 output periscope. The picture shows the old config and I have highlighted what I swapped.

The signal JM3_Y is sent via PCI cards to the channel "H1ASC-JM3_PIT_SUSHTTS" as yaw in the JAC basis is pitch in the IMC basis due to the HAM1 output periscope.

Within the IMC top names block I removed the output channels for the PZT from the WFS feedback path, we already had paths to feedback to JM3 within this path. The picture shows the new config.

I removed the PZT locking path from the LCKIN block and replaced it with one for JM3. The picture shows the new config. I am not sure we ever use this path (which is for dither asc control of the IMC) in the first place so maybe this was unneccessary.

I also removed the channels H1:IMC-PZT_YAW_OUT and H1:IMC-PZT_PIT_OUT from the DAQ channel list for the IMC model.