aLIGO LHO Logbook

H1 SQZ - HAM7 alignment progress

karmeng.kwan@ligo.org — Thu, 15 Jan 2026 16:42:10 -0800

Author: karmeng.kwan@ligo.org

Report ID: 88777

[Sheila, Karmeng]

Today we checked and managed to reduce some of the saturation on ZM4, and offload it onto ZM6. The changes were undone for now.

We briefly did the power budget check, but the power measured at the output of the SFI1 is fluctuating (between 0.79mW to 1.6mW) when the input to SFI1 is at 0.79mW. The power is stable down the propagation (after AP1 and SFI2), unsure what causes the fluctuation. Will continue to look into this tomorrow.

We also did an OMC scan, the pink trace is the scan when ZM4 is in its original setting (YAW: 1779.5), and the red trace is correspond to ZM4 misalignment (YAW: 1769.5).

Images attached to this report

LHO General - Thurs DAY Ops Summary

corey.gray@ligo.org — Thu, 15 Jan 2026 16:32:02 -0800

Author: corey.gray@ligo.org

Report ID: 88769

TITLE: 01/15 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:

Update to "Status of Things": HAM1-2 Septum had a viewport cover removed (so, 3 of 4 are covered) for JAC alignment. ~100mW coming from the PSL to HAM1 for JAC (not noted on the white board).

JAC alignment work continued most of the day. Did not roll IOT2 into place (latest plans are to do this tomorrow [Fri] afternoon) with the LVEA being transitioned to SAFE prior to this work (aiming for lunchtime).

SQZ alignment work continued in the afternoon.

SUS model/daq work appears to be nearing completion (Jeff, Oli, RyanS, Dave (remote), EJ (remote)) !
LOG:

1541-1555 Optics Lab clean (kim)
1606-1712 LVEA cleaning (kim, nellie)
1625-1839 EY parts to LVEA (randy,mitch)
1710-1715 JAC work: PSL lightpipe opening for JAC, no beams out of chamber (masayuki)
- 1717-1724 Checking high voltage (masayuki)
- 1816-2053 Out to HAM1 again (masayuki)
1746-2126 PCal measurements (tony)
1755-1720 MY cleaning (nellie)
1756-1802 Grabbing garb (ibrahim)
1830-1843 pulling/inspecting a mirror mount inside HAM1 for JAC (rahul) + joined by Jason briefly
- 1844-1848 quick trip to optics lab to look for siskiyou mount (corey)
- 1835-2030 EE support for JAC (marc)
1902-1930 JAC (jennie, daniel)
1916-2053 Jason joining JAC crew with 2- LH Siskiyou Mirror Mounts!
1922-1950 swifting FCES (kim)
1927-1937 CER for cable change (oli)
1941 Injection work around BSC2/Beer Garden throughout the day (robert)
2022-2031 Heading out to HAM1 (jennie)
2031-2055 CER to take photo of chasis (jeff, oli)
2130 DAQ Restart (dave)
2200 JAC alignment afternoon work (masayuki, jennie)
- 2210 jason joins
2216-0000 SQZ alignment on floor & in the control room (sheila, karmeng)
2235-2312 Looking for cables at MY (travis)
2347 CER visual check (jeff)
0008 Word of DAQ Restarts done for the day (Dave)
0028 Robert heading back out for injection work near BSC2

H1 PSL - PSL 10-Day Trends

ryan.short@ligo.org — Thu, 15 Jan 2026 14:28:49 -0800

Author: ryan.short@ligo.org

Report ID: 88776

FAMIS 31120

Starting last Thursday, the NPRO temperature is a bit more unstable than usual, but I'm not exactly sure why. There was a brief incursion into the anteroom last Friday, which is seen in the usual places, but everything appears to have come back as expected. The RefCav still looks to need some alignment, which I will likely get to next week. Otherwise, the PSL is looking good.

Images attached to this report

LHO VE - ThuCP1 Fill

david.barker@ligo.org — Thu, 15 Jan 2026 11:09:38 -0800

Author: david.barker@ligo.org

Report ID: 88774

Thu Jan 15 10:08:48 2026 INFO: Fill completed in 8min 45secs

Images attached to this report

H1 PSL - PSL Status Report Weekly FAMIS

oli.patane@ligo.org — Thu, 15 Jan 2026 10:39:44 -0800

Author: oli.patane@ligo.org

Report ID: 88773

Closes FAMIS#39747, last checked 88725

Laser Status:
NPRO output power is 1.845W
AMP1 output power is 70.39W
AMP2 output power is 139.1W
NPRO watchdog is GREEN
AMP1 watchdog is GREEN
AMP2 watchdog is GREEN
PDWD watchdog is GREEN

PMC:
It has been locked 6 days, 18 hr 2 minutes
Reflected power = 26.47W
Transmitted power = 104.5W
PowerSum = 131.0W

FSS:
It has been locked for 2 days 23 hr and 18 min
TPD[V] = 0.4029V

ISS:
The diffracted power is around 4.0%
Last saturation event was 0 days 0 hours and 0 minutes ago

Possible Issues:
PMC reflected power is high

LHO General - Thurs DAY Ops Transition

corey.gray@ligo.org — Thu, 15 Jan 2026 09:12:33 -0800

Author: corey.gray@ligo.org

Report ID: 88768

TITLE: 01/15 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: 9mph Gusts, 5mph 3min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.25 μm/s
QUICK SUMMARY:

JAC work continues with ~~IOT2L being rolled up to HAM2 this morning for~~ [IOT2 will be later today or Fri] alignment checks & IMC locking. Equipment moves in LVEA and from EY, and I believe there is more Squeezer alignment as well at HAM7.

H1 PEM - HVAC Fan Vibrometers FAMIS Check (FAMIS 39850)

corey.gray@ligo.org — Thu, 15 Jan 2026 07:57:50 -0800

Author: corey.gray@ligo.org

Report ID: 88771

For FAMIS #39850: All fan trends look nice and flat.

Images attached to this report

H1 SQZ - HAM7 beam aligned to HAM6

sheila.dwyer@ligo.org — Thu, 15 Jan 2026 07:46:42 -0800

Author: sheila.dwyer@ligo.org

Report ID: 88767

Kar Meng, Sheila

This afternoon we aligned the squeezer beam to AS_C, AS_A, and AS_B QPDs. This is currently done with OM1, OM2, SRM, and ZM6 at the same alignment they were at in the end of O4. That means that the beam location on ZM5 should be the same as it was at the end of O4 (75732). With this alignment, we are using up most of the actuator range on ZM4, so we will either have to move ZM6 and the spot position on ZM5, or mechanically yaw ZM4. We can't easily reach ZM5 with an IR card to check if the beam position on it is centered, if we can find a way to get an IR card on a long stick to asses that centering that would be helpful.

As part of this, we set up alignment loops from AS_A to ZM4 and AS_B to ZM5, they are slow but reliable. I will attach a screenshot of settings here tomorow.

We also checked the alignment of the beam onto the CLF FIBER rejected PD, which was off because the fiber collimator was tilted to realign the the new OPO cavity axis. Kar Meng adjusted the pitch of the TFP, then slid the PD to center the beam in yaw, and lastly yawed the PD to make sure the reflection was going nicely to the black glass V.

LHO General - Comment to Thurs DAY Ops Transition

corey.gray@ligo.org — Thu, 15 Jan 2026 07:45:05 -0800

Author: corey.gray@ligo.org

Report ID: 88770

Once again, Dust Monitor LAB2 has a "not a number" ERROR, all others OK/correct.

LHO General - Wed DAY Ops Summary

corey.gray@ligo.org — Wed, 14 Jan 2026 16:31:10 -0800

Author: corey.gray@ligo.org

Report ID: 88760

TITLE: 01/14 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:

Today's big activities: JAC alignment continues at HAM1. SUS model/daq work continues from Control Room and CER. HAM7 squeezer alignment continues.
LOG:

1545 sus model/daq begins with daq restart (jonathan/cds)
- 1810 CER (olli,jeff)
- 1828 CER for power supply rack install (marc)
- 2124 Oli left + Marc went out again to help with AntiAlias issue.
- 2228 Jeff confirms Marc's work was complete and CER work is done.
1556-1704 LVEA technical cleaning, checks, prep (kim.nellie)
- 1758 Kim back to LVEA
1653-1937 Checking lasers and taking meeting in PCal Lab area (tony)
1713 nuc20 restarted for a new CDS Overview (dave)
1743-2337 Y-arm trailer moves to EY (randy)
1747 HAM1 JAC begins morning work(Masayuki)
- 1811 -1855 Rahul
- 1814-1842, 1934- Jennie
- 1913 Betsy running parts out
1845-1854 Parts search (travis)
1936-1942 Checking light fixture in LVEA (eric)
2017-0008 HAM7 alignment work continuing (sheila,karmeng)
- 2207 Sheila/Karmeng out for control room work
- 2309 Sheila/Karmeng back to HAM7
2119 JAC Alignment for afternoon (jennie,masayuki,keita)
- 2119 Gerardo joining to help with VAC/viewports
- 2155 Jennie out
- 2306 Jennie, Jason heading to HAM1
- 2336 Rahul out, 2359 Jason out
2150-2354 Switching integrating spheres in PCal lab (tony)
2200-2235 putting panels back on chasis in CER (dave)

H1 SUS - SUS-C1 and SUS-C6 AI Chassis Modified, SUS-C2 Modified AI Chassis Installed

oli.patane@ligo.org — Wed, 14 Jan 2026 14:54:57 -0800

Author: oli.patane@ligo.org

Report ID: 88766

Marc, Jeff, Fil, Oli

Yesterday we pulled most of the AI chassis (D1000305 or D1600077) from SUS-C1 and SUS-C6, modified them for ECR E2400409 and E2500296 (IIET 35739 and 35706, respectively), and reinstalled them as part of our work converting SUSB123 and SUSH34 into SUSB13 and SUSB2H34 (88765).

Every AI chassis in SUS-C1 and SUS-C6 was meant to be pulled, upgraded, and reinstalled EXCEPT SUS-C1 U24. Additionally, we needed to also modify a spare D1000305 AI chassis for installation into SUS-C2. We did all this, but along the way we accidentally also pulled and upgraded the AI chassis in SUS-C1 U24 (previously S1104380). Luckily, we hadn't modded the spare (S2100712) yet so we installed it into SUS-C1 U24 and installed that modified chassis in the SUS-C2 U14 spot.

Here are the steps for how we modified the AI chassis:
- Disconnected all affected AI output cables in SUS-C1 and SUS-C6
- Removed the existing 6x 2x 8CH DAC AI chassis (D1000305 or D1600077),
- Modified them to become D2500353 1x 32CH AI chassis
. Replaced the 2x 8CH AI rear panel with WD relays (D1000551) with 1x 32CH AI rear panel without WD relays (D2500097)
. Replaced the 2x 8CH back panel (D1000552 with 1x 32CH back panel (D2400308)
- Relabeled AI chassis from D1000305 to D2500353, or from D1600077 to D2500397, and reinstalled
- Cabled everything up according to the corresponding version of the wiring diagram (SUSB13, SUSB2H34)

Pulled, upgraded, and reinstalled:
D1000305 > D2500353 D2500097 SUS Chain Rack / Position Chassis S/N Rear Board S/N 32CH DAC Card / IO Slot Channels ITMY M0/R0/L1 SUS-C6 / U38 S1108073 S2501317 DAC0 / Slot#2 0-15

ITMX M0/R0/L1 SUS-C6 / U37 S1108072 S2501319 DAC0 / Slot#2 16-31

ITMY L2, ITMX L2 SUS-C6 / U35 S1108074 S2501316 DAC1 / Slot#4 0-15

MC2 M1,PR2 M1,SR2 M1 SUS-C1 / U31 S1104379 S2501321 DAC2 / Slot#5 0-15

SR2 M1, MC2 M2/M3 SUS-C1 / U30 S1104368 S2501320 DAC2 / Slot#5 16-31

D1600077 > D2500397 Chassis S/N ITMX ESD, ITMY ESD SUS-C6 / U21 S1600245 S2501318 DAC1 / Slot#4 16-27

Upgraded and newly installed (technically was pulled from SUS-C1 U24 by accident): BS M1/M2 SUS-C2 / U14 S1104380 S2501322 DAC3 / Slot#6 0-11

NOT upgraded but chassis swapped: D1000305 D1000305 SUS Chain Rack / Position Chassis S/N Before Chassis S/N Now PR2 M2, PR2 M3, SR2 M2, SR2 M3 SUS-C1 / U24 S1104380 S2100712

H1 SUS - CER Hardware/Electronics Changes To Convert SUSB123 and SUSH34 to SUSB13 and SUSH34 Complete; User Model Software Changes Commencing

jeffrey.kissel@ligo.org — Wed, 14 Jan 2026 14:09:20 -0800

Author: jeffrey.kissel@ligo.org

Report ID: 88765

J. Kissel, F. Clara, O. Patane, M. Pirello, D. Barker ECR E2500296, E2400409 WP 12962 D2300401 (for susb13) and D2300383 (for susb2h34) G2301306 -- PARTII 2023 plan, PARTII Update We've completed all electronics hardware moves, cabling/recabling and new installations that we plan to do on SUS MC2, PR2, SR2, BS, and the future LO1 and LO2 for now. Given that this change to the electronics is somewhere in between versions of the D2300401 h1susb13 and D2300383 h1susb2h34 wiring diagrams -- the interim configuration we're in now that Does have - susb2h34 and susb13, as well as susauxb13 and susauxb2h34 with all their ADC and DAC cards, as they will be in O5. - All of the BS electronics have been moved from SUS-C5/SUS-C6 to SUS-C1/SUS-C2, and their CER cabling dragged along with it - all AI chassis driven by 28-bit 32CH DACs (7 in total) have been converted from a pair of D1000305 2x8CH DAC AIs to a pair of D2500353 1/2x32CH DAC AIs. - ITM AA chassis inputs (both OSEM sensors, optical levers, and CD monitors) and AI chassis outputs have been re-arranged such that the grouping is far more sensibly arranged and modular per QUAD. Doesn't have - BBSS-like BS TOP mass converted to QOSEMs - BBSS-like BS M3 OSEM sensing and actuation electronics - Any LO1 or LO2 electronics - The BS optical lever in its final AA chassis position (because the BS TOP mass OSEMs still need that spot) - Any changes to the field cabling - the BS M1 satamps, M2 satamps, and M3 optical lever whitening chassis are all still in SUS-R6) -- we planned /documented all of this work on google slides -- see PARTII Update -- which is linked in the abstract of G2301306. We'll add more details, gotchas, and pictures below in the comments.CDS, IOO, ISC, SUS

LHO VE - Wed CP1 Fill

david.barker@ligo.org — Wed, 14 Jan 2026 10:52:06 -0800

Author: david.barker@ligo.org

Report ID: 88764

Wed Jan 14 10:10:16 2026 INFO: Fill completed in 10min 12secs

Images attached to this report

H1 SQZ - Comment to VOPO measurement setup

karmeng.kwan@ligo.org — Wed, 14 Jan 2026 10:47:45 -0800

Author: karmeng.kwan@ligo.org

Report ID: 88763

I have included a diagram showing the components remaining on the optical table, which can be used for testing the homodyne detector.

The attached file also includes the corresponding mode-matching calculation, indicating the resulting beam waist location along the remaining optical path, for future reference.

Non-image files attached to this report

modematching_for_optics_lab_setup.pdf

LHO General - Comment to Wed DAY Ops Transition

corey.gray@ligo.org — Wed, 14 Jan 2026 08:13:02 -0800

Author: corey.gray@ligo.org

Report ID: 88762

My last shift was in 2025. Some notes:

HAM1 ISI WD tripped 8-days ago--assuming for JAC in-chamber work (updated white board)
BSC 1/2/3 OFFLINE (updated white board)
Too foggy to check arms for tumbleweeds with cameras.
Dust Monitor LAB2 has a "not a number" ERROR, all others OK/correct.

H1 CDS - CDS BS move and LIGO-DAC upgrade

david.barker@ligo.org — Wed, 14 Jan 2026 07:38:40 -0800

Author: david.barker@ligo.org

Report ID: 88761

Fil, Marc, Richard, Jeff, Oli, Erik, EJ, Jonathan, Dave:

WP12962 Move BS for upgrade to BBSS. WP12901 Upgrade ITM to LIGO-DAC

On Tuesday 13Jan2026 we reconfigured the BSC1,2,3 and HAM3,4 suspensions to move the BS control from h1susb123 to h1sush34 and upgrade the ITM test mass suspensions to use the new LIGO-DACs. Associated changes were also made to these systems' SUS-AUX frontends.

Frontend Computer Renaming:

old name	new name
h1susb123	h1susb13
h1sush34	h1susb2h34
h1susauxb123	h1susauxb13
h1susauxh34	h1susauxb2h34

Prep Work:

The 4 LIGO-DACs used for this upgrade were calibrated in the EE shop and FE tested on the DTS.

The EDC was moved from h1susauxb123 to h1susauxh56

Upgrade:

The h1susb123 and h1sush34 suspensions were SDF reconcilled and put into their safe state.

The SWWD seismic systems were put into an infinite bypass.

All 4 front end were powered down and work on their IO Chassis, AAs and AIs started.

h1susb13 IO Chassis

8 20bit-DACs removed, 2 LIGO-DACs added.

Removed 20bit-DACs

20bit-DAC	18/20bit-DAC Interface Card
200217-17	S1200228
220218-29	S1200227
210303-49	S1200224
210303-35	S1200219
210303-22	S1200220
200217-19	S1200221
210303-57	S1200226
220218-08*	S1200229

* 20bit-DAC 220218-08 installed in new h1susb2h34 chassis.

New Adnaco Layout

Adnaco slot	Card [interface]	Adnaco slot	Card [Interface]
A1-1	LIGO Timing Card	A3-1	empty
A1-2	empty	A3-2	empty
A1-3	ADC0 (orig)	A3-3	empty
A1-4	LIGO-DAC0 S2500457 [010]	A3-4	empty

A2-1	ADC1 (origin)	A4-1	BIO0 (orig)
A2-2	LIGO-DAC1 S2500448 [011]	A4-2	BIO1 (orig)
A2-3	empty	A4-3	BIO2 (orig)
A2-4	empty	A4-4	empty

h1susauxb13 IO Chassis

Removed last 2 ADCs, installed them in h1susauxb2h34 IO Chassis. ADC count went from 8 to 6.

h1susauxb2h34 IO Chassis

Added the 2 ADCs from h1susauxb13 in next available slots. ADC count went from 6 to 8.

ADC	ADC Card	Interface Card
ADC6	110128-11	S1102417
ADC7	110128-03	S1301433

h1susb2h34 IO Chassis

Original layout skipped Adnaco slot A2-4. Reviewed as-built drawings and alog but could not find why this slot was not being used. Assuming that there was something wrong with this slot I replaced the second Adnaco backplane

Suspect Backplane (removed)	C8610415
New Backplane (installed)	C8610796

Original layout was:

2 ADC, 5 18bit-DAC, 1 20bit-DAC, 2 BIO.

Update: keep the 2 ADCs, remove all 5 18bit-DACs, keep the 1 20bit-DAC and add a second 20bit-DAC, add 2 LIGO-DACs and add a third BIO.

Table of removed 18bit-DACs + IF

18bit-DAC	Interface Card
110425-10	S1104013
101208-71	S1104017
110425-04	S1104014
110425-09	S1104023
110425-46	*

* Because the 18bit and 20bit DACs use the same Interface card, this IF card was left in the chassis for the second 20bit-DAC

New Adnaco layout

Adnaco slot	Card [Interface]	Adnaco slot	Card [Interface]
A1-1	LIGO Timing Card	A3-1	empty
A1-2	empty	A3-2	empty
A1-3	ADC0 (orig)	A3-3	empty
A1-4	20bit-DAC0 (orig)	A3-4	empty

A2-1	ADC1 (orig)	A4-1	BIO0 (orig)
A2-2	20bit-DAC1 *	A4-2	BIO1 (orig)
A2-3	LIGO-DAC0 S2500454 [012]	A4-3	BIO2 ADRBS96001188
A2-4	LIGO-DAC1 S2500442 [013]	A4-4	empty

* 20bit-DAC1 ss0218-08 repurposed from h1susb123 surplus.

Timing Card Firmware Upgrade (Marc)

All 4 IO Chassis Timing Cards had a firmware upgrade. This was essential for the control frontends, which would not be able to drive the LIGO-DACs without the new firmware. The SUS-AUX TCs were upgraded as part of the general upgrade of all frontends.

	Tming Card Firmware Version
old	1 - 0x1f0
new	2 - 0x635

Model Changes and Current Status

h1iopsusb13	New model name, installed but needs SWWD review
h1susitmx	Not running, being reworked
h1susitmy	Not running, being reworked
h1susitmpi	Not running, being reworked
h1iopsusb2h34	New model name, installed but needs SWWD review
h1susbs	New location, not running, being reworked
h1susmc2	Not running, being reworked
h1suspr2	Not running, being reworked
h1sussr2	Not running, being reworked
h1iopsusauxb13	New model name, running and complete
h1susauxb13	Temporary model running, being reworked
h1iopsusauxb2h34	New model name, running and complete
h1susauxb2h34	Temporary model running, being reworked

All models are being built with RCG5.5.2, which is needed to drive more than 1 LIGO-DAC.

LHO General - Wed DAY Ops Transition

corey.gray@ligo.org — Wed, 14 Jan 2026 07:37:00 -0800

Author: corey.gray@ligo.org

Report ID: 88759

TITLE: 01/14 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: 6mph Gusts, 4mph 3min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.45 μm/s
QUICK SUMMARY:

Foggy morning on site where the LVEA continues to be in Laser HAZARD for in-chamber work at HAM1 & HAM2.

MuseumEXP continues with new-exhibit work at LExC this week.

H1 IOO - Comment to Locking JAC in air

jennifer.wright@ligo.org — Tue, 13 Jan 2026 18:46:00 -0800

Author: jennifer.wright@ligo.org

Report ID: 88758

Here is the measurements we took so far.

Offset Locking erro point ASD when locked.

Dither locking error point ASD when locked.

Dither locking open loop gain.

Images attached to this report

H1 IOO - Locking JAC in air

jennifer.wright@ligo.org — Tue, 13 Jan 2026 18:38:30 -0800

Author: jennifer.wright@ligo.org

Report ID: 88757

Jennie W, Masayuki N

Daniel set up some model changes last week in h1lsc to allow us to use the JAC-TRANS_A DCPD to lock the cavity. This is a workaround of what is intended to be the normal operation where the locking is done with the JAC-REFL_A PD on IOT1. Rolling this table up to the chamber would make it hard to install the optics on that side of the table so we need this workaround to see the beam transmitted through the cavity that we can use to align the beam from JAC into the IMC.

This PD is just a DC PD so we cannot use PDH to lock as we would for the REFL PD. Yesterday and today Masayuki and I worked on an offset lock, where we use the transmitted power offset to the side of the fringe after normalising the error signal by the maximum transmitted power on resonance.

Use JAC Overview->DITHER. The demodulation is set up so the SIN gain is one and connects to I filter bank which also has a gain of 1. Q filter bank is terminated at the output.

First step is to use the ramp on JAC Overview -> JAC-PZT_Driver by pressing "ENABLE" in right-hand corner, the slider on the left side needs to be near -10V for this to work. Measure the max peak height of the TM00 mode - transmitted power off resonance.

The normalisation is done using the high pass filter bank block at the left of the screen, this opens up H1JAC-DITHER_PD_IN. The gain should be set to the normalisation constant, 1/(transmitted power on resonance - transmitted power off resonance).

The actual servo shaping is done using H1JAC-DITHER_SERVO, which is linked on the right of the 'DITHER' screen. Set the offset to -0.6 to shift the normalised error signal so the zero crossing is just below halfway up the fringe. Check the input and output of the filter bank after the servo are turned on, this is linked on the right of the 'DITHER' screen and is called 'PZT'.

Make sure the PZT ramping is turned off by pressin 'DISABLE on the JAC-PZT_Driver screen.

Turn on the UGF100 and LP10 filters in the 'H1JAC-DITHER_SERVO' filter bank. These have a gain of 3000 and a low pass filter which rolls off at 10Hz respectively. This latter one is to invert the PZT response.

The gain in this filter bank should be on, use the slider on the 'DITHER' screen to tune to a TM00 peak and then turn on the servo output. Once locked you can turn on the Int1Hz filter to add an integrator below 1Hz and the boost to give an extra 5x gain.

For a better lock we also implemented a proper DITHER SERVO.

The dither frequency is set to 2.5KHz and the demod phase is set at 0 degrees. The input signal no longer had normalisation in H1JAC-DITHER_PD_IN as the error signal will now be the beat between the PZT dither and the cavity transmitted power and so has a zero crossing at the centre of resonance.

There is a high pass filter in H1JAC-DITHER_PD_IN to avoid up-conversion of noise below 1 kHz. After the demodulation both 'I' and "Q' filter banks have a low pass filter at 1kHz to prevent 2.5kHz and harmonics from getting magnified by the loop.

Both I and Q phase now have a low pass filter at 1KHz to prevent harmonics of the dither frequency appearing in the error signal. The locking technique is the same after this point as the filters needed in the 'SERVO' block do not change as the actuator response has not changed.

Masayuki has set up both these locking processes in the JAC guardian but this is still WIP.

ISC

Images attached to this report

H1 SEI - Power supply at EX failed killing EX ISI cps timing

jim.warner@ligo.org — Tue, 13 Jan 2026 17:55:49 -0800

Author: jim.warner@ligo.org

Report ID: 88756

RyanS told me yesterday that he could re-isolate the ETMX ISI. I finally got to looking at it today and something was off with the CPS. Using the weekly CPS spectra script I got ASDs for the CPS from last night and a bunch of the the CPS spectra were way off, first image.

I went to EX and looked at racks, SEI chassis all looked fine. I unplugged a couple of CPS probes at the chamber and did not get the expected behavior. One CPS went to the near limit rail (-32k) the others hardly changed at all. This made me suspect timing, so I traced out the timing sync wires, found the 71Mhz CPS timing fanout and the lights were all off. Looked at the power strip and only the -18v led was on. Turned off the fanout chassis, took some pics and found Marc and Fil.

Marc came to the end and we looked at power supplies in the front of the building and the +18 for the rack was dead. We swapped both power supplies for spares, and CPS timing seems to have come back, I was able to isolate the ISI. Marc said the fans seemed a bit stiff and smelled weird, so maybe another fan failure.

Images attached to this report

H1 AOS - Replaced Kepco Supplies EX, ISC-R1 +/- 18V

marc.pirello@ligo.org — Tue, 13 Jan 2026 17:32:51 -0800

Author: marc.pirello@ligo.org

Report ID: 88755

Per WP12970

ISC-R1 +18V supply failed this afternoon. This set was slated for replacement, so we replaced both legs.

+18V S1300287 was replaced with S1202002 with new ball bearing fan installed.
-18V S1300275 was replaced with S1201995 with new ball bearing fan installed.

M. Pirello, J. Warner

LHO VE - Tue CP1 Fill

david.barker@ligo.org — Tue, 13 Jan 2026 17:00:14 -0800

Author: david.barker@ligo.org

Report ID: 88754

Tue Jan 13 10:09:38 2026 INFO: Fill completed in 9min 34secs

Images attached to this report

LHO General - Ops Day Shift Summary

ryan.short@ligo.org — Tue, 13 Jan 2026 16:33:41 -0800

Author: ryan.short@ligo.org

Report ID: 88753

TITLE: 01/14 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: Another busy day of upgrades; JAC installation and HAM7 beam alignment continued while the move/upgrade of BS DACs began today and should wrap up tomorrow morning. Jim also discovered a failed power supply at EX which looks to be the reason the chamber can't be recovered, so he and Marc are starting to take action there.
LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
----	SAF	HAZARD	LVEA	YES	LVEA is Laser HAZARD	Ongoing
16:27	FAC	Kim, Nellie	LVEA	-	Technical cleaning	17:18
16:41	CDS	Marc, Fil, Oli	CER	-	SUS computer upgrades	20:22
16:49	CDS	Jeff	CER	-	SUS computer upgrades	21:04
16:49	CAL	Tony	PCal Lab	Local	Check measurement	20:17
17:01	JAC	Rahul	LVEA	Y	JAC installation	19:42
17:24	SQZ	Sheila, Elenna, Kar Meng	LVEA	Y	HAM7 SQZ beam alignment	18:25
17:27	JAC	Jennie	LVEA	Y	Opening light pipe	17:33
18:30	CDS	Dave	CER	-	susb123 DAC upgrades	22:33
18:32	JAC	Masayuki	LVEA	Y	JAC installation	19:42
18:55	SQZ	Elenna	LVEA	-	Replacing viewport cover	19:07
18:56	VAC	Gerardo	EX	N	Troubleshoot AIP	19:36
18:57	FAC	Kim	EX	N	Technical cleaning	19:36
19:24	FAC	Tyler, MacMiller	FCES	N	Air handler work	22:33
20:01	CDS	Richard	CER	-	Checking progress	20:30
20:22	CDS	Fil	MY	N	Picking up cables	23:09
20:22	CDS	Oli	CER	-	SUS computer upgrades	21:05
21:11	VAC	Gerardo	EX	N	Troubleshoot AIP	21:30
21:13	CAL	Tony	PCal Lab	Local	Getting serial numbers	00:08
21:17	VAC	Travis	LVEA	-	Looking for parts	21:24
21:45	CDS	Jeff	CER	-	SUS computer upgrades	00:18
21:51	JAC	Jennie, Rahul	LVEA	Y	JAC installation, Rahul out @ 22:47	01:25
22:10	JAC	Masayuki	LVEA	Y	JAC installation	01:25
22:24	CDS	Oli	CER	-	SUS computer upgrades	01:11
22:35	JAC	Betsy	LVEA	-	Check on JAC progress	22:47
22:35	JAC	Keita	LVEA	-	JAC installation	01:25
22:35	PEM	RyanC	CER	-	Grabbing DM stand	22:38
22:54	CDS	Marc	MY	N	Getting parts	23:11
23:10	CDS	Fil	CER	-	SUS computer upgrades	01:10
23:23	SQZ	Sheila	LVEA	Y	Opening HAM7 viewport cover	23:29
23:52	SEI	Jim	EX	N	Checking electronics	00:25
00:02	VAC	Travis	Mids	N	Looking for parts	00:31

H1 SQZ - HAM7 early part of this week

sheila.dwyer@ligo.org — Tue, 13 Jan 2026 16:31:32 -0800

Author: sheila.dwyer@ligo.org

Report ID: 88751

Sheila, Kar Meng, Elenna, Jim

Yesterday Jim and I went to the chamber in the morning to work on cables. We got a solution for the cables after some work, but one peek zip tie luanched itself across the chamber. We spent a few hours searching for this; I climbed into the chamber on the -X side and could them see it on the bottom of the +Y door where Jim was able to reach through the port and retreive it.

In the afternoon Kar Meng and I went back to the chamber and found that the beam was blocked on the cable clamp that Jim and I had added earlier. The previous cable routing is shown here, the peek cable clamp is on the bottom of the pillar so that it doesn't block the beam. We removed the new alumium clamp and I tried to move it lower, the second from the top bolt hole is not the right size so we need to place this in the 3rd from the top hole. I found that difficult to reach and eventually decided to leave it for another day or ask for help from someone with longer reach.

After this we saw that our beam did arrive on AS_C in HAM6 but wasn't aligned onto AS_A or AS_B.

This morning Elenna, Kar Meng and I went to the chamber to see if we could improve the alignment. We walked B:M3 to align onto the second iris on SQZT7, and B:M4 to align onto the iris in front of ZM4, which seems degenerate with the iris at the bottom of the SQZT7 periscope. This worked well and we could see light on AS_B and AS_C although nothing on AS_A. We then went to the control room and moved ZM6 to center on AS_C better, then we could engage the AS centering loops.

This afternoon Kar Meng and I had another look at alignment from the control room. We have set the OMs back to their alignments during the run, and we still have the beams on AS_C, AS_A and AS_B although we are using a lot of the range on ZM6.

Still to do before finishing in HAM7:

adjust alignment to relieve range on ZM6
add cable clamp on bottom of OPOsus pillar near B:M4, without blocking beam
Photos of cables as we are leaving them
unlock VIP
photos of iris locations and beams on them
power budget measurements: with power meter at various points on VIP, seed reflected power and seed power to homodyne path
realign beam onto FC QPDs
check alignment onto other photodiodes in chamber
remove irises
unlock ISI, SUS and ISI checks

H1 AOS - Comment to HAM1 update - added some lenses and mirrors for JAC

rahul.kumar@ligo.org — Tue, 13 Jan 2026 16:22:23 -0800

Author: rahul.kumar@ligo.org

Report ID: 88749

Pictures attched from HAM1 chamber.

Images attached to this report

H1 SUS - Comment to H1SUSB123 and H1SUSH34 SUS and SEI Systems prepped in SAFE for Conversion to SUSB13 and SUSH34

marc.pirello@ligo.org — Tue, 13 Jan 2026 16:20:14 -0800

Author: marc.pirello@ligo.org

Report ID: 88752

Updated timing cards on newly named SUSB13, SUSB13 AUX, SUSB2H34, SUSB2H34 AUX, formerly known as SUSB123, SUSB123 AUX, SUSH34 and SUSH34 AUX.

Timing FPGA Version 1589

LHO VE - Comment to X2-8 Ion Pump Out of Service

gerardo.moreno@ligo.org — Tue, 13 Jan 2026 14:51:57 -0800

Author: gerardo.moreno@ligo.org

Report ID: 88750

(Travis, Gerardo, Richard)

Controller remains off, and high voltage cable is disconnected at both ends, ion pump and controller.

We found a controller for this particular application, and replaced the "old" controller but with similar results, minus the noise. The controller was only able able to get up to 500 volts and no more. We turned it off and disconnected the high voltage cable.

I later visited the cable and ion pump to measured them for shorts. I disconnected the cable from the ion pump, then probed the connector at the controller side, center pin to the shell read 0.808 kOhm, I also probed the center connector to other parts of the cable, but no continuity was read for all cases, including to the conduit. The ion pump itself was probed for shorts and none was found, at the ion pump connector the center pin was probed to the ion pump body and no continuity was measured. To compare cables, I measured a "new" cable that we have that is probably half the length of the one in use, no continuity was measured.

I'll wait for the EE guys to have a free moment for them to test the cable.

Images attached to this report

H1 AOS - HAM1 update - added some lenses and mirrors for JAC

rahul.kumar@ligo.org — Tue, 13 Jan 2026 13:35:10 -0800

Author: rahul.kumar@ligo.org

Report ID: 88748

Masayuki, Jennie, Rahul

Given below are the list of lenses and mirrors I have placed on the ISI table and roughly positioned (without the beam for now) them as per following drawings - D2500344 and D0901821.

Lenses - L1, L2 and L3: Masayuki confirmed from the vendor that the arrow mark on the lens point towards the convex side. For lens L1, arrow is pointing against the PEEK ring (in the lens holder). For Lens L2 and L3 the arrow is pointing towards the PEEK ring. The PEEK ring for all three lens are facing towards the HAM2 chamber. In other words, curved surface of L1 is facing towards the PSL and for L2-3 towards HAM2.

I re-cleaned L1 lens after finding some dust particles on the curved surface, post cleaning the lens looked better.

Reflecting mirrors - JAC-RM1, JAC-RM2, JM2 and M3.

Masayuki and I also added a temporary Siskyou mount acting as JM3 (for Tip Tilt, just like JM1). We will replace both of them with the Tip Tilt next week.

Next, we proceed with aligning/pointing the above optics with the beam. L1 and JM2 are already decently pointing (although without a locked JAC) towards JM3.

H1 IOO - Comment to JAC working log 1/8-9

corey.gray@ligo.org — Tue, 13 Jan 2026 11:22:08 -0800

Author: corey.gray@ligo.org

Report ID: 88747

Tagging for EPO photos

EPO

H1 IOO - Comment to JAC in HAM1

corey.gray@ligo.org — Tue, 13 Jan 2026 11:21:52 -0800

Author: corey.gray@ligo.org

Report ID: 88746

Tagging for EPO photos

EPO

H1 SUS - H1SUSB123 and H1SUSH34 SUS and SEI Systems prepped in SAFE for Conversion to SUSB13 and SUSH34

jeffrey.kissel@ligo.org — Tue, 13 Jan 2026 08:45:24 -0800

Author: jeffrey.kissel@ligo.org

Report ID: 88745

J. Kissel ECR E2500296, E2400409 WP 12962 D2300401 (for susb13) and D2300383 (for susb2h34) We begin the major upgrade of the H1SUSB123 and H1SUSH34 SUS and SEI Systems converting them to SUSB13 and SUSH34 a la G2301306 today. We're focusing on upgrading the DACs in the IO chassis () and all the downstream surrounding impact of that analog electronics This will take down the following computers, and they will be resurrected with new names as follows: FORMER NAME FORMER SUS NEW NAME NEW SUS h1susb123 ITMX, ITMY, BS h1susb13 ITMX, ITMY h1sush34 MC2, PR2, SR2 h1susb2h34 BS, MC2, PR2, SR2, LO1, LO2 h1susauxb123 ITMX, ITMY, BS h1susauxb13 ITMX, ITMY h1susauxh34 MC2, PR2, SR2 h1susauxb2h34 BS, MC2, PR2, SR2, LO1, LO2 As such, I've - brought the ITMX, ITMY, BS, HAM3, and HAM4 SEI systems to ISI_DAMPED_HEPI_OFFLINE (so we don't risk any "hard" trips of HEPI during all this). - brought all impacted SUS gaurdians to AUTO mode, then to the SAFE state - Increased the bypass time on all impacted software watchdogs to bypass time to a large number (90000000 secs), and hit BYPASS CDS, SEI

LHO General - Ops Day Shift Start

ryan.short@ligo.org — Tue, 13 Jan 2026 08:22:25 -0800

Author: ryan.short@ligo.org

Report ID: 88744

TITLE: 01/13 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: 5mph Gusts, 3mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.49 μm/s
QUICK SUMMARY: CDS upgrades this morning; moving SUS in BSC2 over into the sush34 model and upgrading to LIGO DACs. JAC installation and HAM7 beam alignment will continue as well today.

H1 CDS - Workstations updated

erik.vonreis@ligo.org — Tue, 13 Jan 2026 06:52:39 -0800

Author: erik.vonreis@ligo.org

Report ID: 88743

Workstations were updated and rebooted. OS packages were updated. Conda packages were not updated.

H1 CDS - Comment to h1lsc model restart, DAQ restart, EDC move, add JAC_LOCK guardian channels to EDC.

david.barker@ligo.org — Mon, 12 Jan 2026 16:59:06 -0800

Author: david.barker@ligo.org

Report ID: 88742

Mon12Jan2026
LOC TIME HOSTNAME MODEL/REBOOT
14:51:52 h1lsc0 h1lsc <<< Daniel's latest model

14:56:29 h1susauxh56 h1edc[DAQ] <<< EDC move to susauxh56
15:06:45 h1susauxh56 h1edc[DAQ]

15:11:30 h1daqgds1 [DAQ] <<< DAQ restarts
15:15:34 h1daqdc1 [DAQ]
15:15:41 h1daqdc1 [DAQ]
15:15:47 h1daqfw1 [DAQ]
15:15:47 h1daqnds1 [DAQ]
15:15:47 h1daqtw1 [DAQ]
15:16:32 h1daqgds1 [DAQ]
15:25:15 h1daqnds0 [DAQ]
15:25:26 h1daqfw0 [DAQ]
15:25:27 h1daqgds0 [DAQ]
15:25:29 h1daqfw0 [DAQ]
15:25:29 h1daqnds0 [DAQ]
15:25:29 h1daqtw0 [DAQ]

H1 CDS - h1lsc model restart, DAQ restart, EDC move, add JAC_LOCK guardian channels to EDC.

david.barker@ligo.org — Mon, 12 Jan 2026 16:46:56 -0800

Author: david.barker@ligo.org

Report ID: 88741

Daniel, Ryan S, Erik, Jonathan, Dave

In preparation to tomorrow's work on h1susauxb123 we decided to move the EDC from here to h1susauxh56. We did this at the same time the DAQ was being restarted for:

1 Daniel's new h1lsc model

2 Adding Ryan's JAC_LOCK guardian node to EDC

The EDC move had a few configuration issues which were quickly resolved. There were no issues with the h1lsc restart.

LHO General - Ops Day Shift Summary

ryan.short@ligo.org — Mon, 12 Jan 2026 16:31:35 -0800

Author: ryan.short@ligo.org

Report ID: 88740

TITLE: 01/13 Day Shift: 1530-0030 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: Laser safe in the LVEA this morning for some craning and cabling, both in-chamber and out, but now back to laser HAZARD for more JAC installation and SQZ beam alignment this afternoon.
LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
----	SAF	HAZARD	LVEA	YES	LVEA is Laser HAZARD	Ongoing
15:15	FAC	Randy, Eric	LVEA	N	Craning	16:45
15:58	FAC	Kim, Nellie	LVEA	N	Garb & garbage	16:28
16:14	SAF	Richard	LVEA	N	Grabbing keys	16:17
16:46	FAC	Kim, Nellie	LVEA	N	Technical cleaning	17:42
16:50	CDS	Marc, Fil	LVEA	N	Checking panel placement	18:06
16:51	CAL	Tony	PCal Lab	Local	Start measurement	17:42
16:59	FAC	Randy	LVEA	N	Craning	17:24
17:12	VAC	Gerardo	EX	N	Troubleshoot ion pump	17:37
17:28	SQZ	Sheila, Jim	LVEA	N	HAM7 cabling	19:24
17:34	JAC	Jennie, Rahul	LVEA	N	JAC optics	18:06
17:39	PEM	RyanC	LVEA	N	Checking dust monitors	18:18
18:06	CDS	Fil, Marc	LVEA	N	Cable pulling input arm	20:17
18:11	JAC	Jennie, Rahul	LVEA	N	JAC optics	19:11
18:28	FAC	Randy	LVEA	N	Walkabout	18:40
18:33	PEM	RyanC	EY, EX	N	Checking dust monitors	19:37
18:40	FAC	Randy	EY	N	Dropping off equipment	20:31
18:43	FAC	Kim, Nellie	LVEA	N	Technical cleaning	19:31
18:58	FAC	Tyler	LVEA, MX, MY, EX, EY	N	3IFO checks	20:58
19:31	FAC	Kim	MX	N	Technical cleaning	20:04
19:35	VAC	Gerardo	LVEA	N	Looking for parts	19:48
19:58	SQZ	Sheila, Jim	LVEA	N	HAM7 cabling	20:29
20:37	SAF	RyanC	LVEA	Y	Laser HAZARD transition	20:53
21:04	JAC	Jennie	LVEA	-	Turning on JAC HV	21:07
21:09	FAC	Richard, Tyler, contractors	LVEA	-	Electrical checks near HAM1	21:53
22:11	VAC	Gerardo, Travis	EX	N	Replacing AIP controller	23:00
22:14	SQZ	Sheila	LVEA	Y	Turning on SQZ laser, opening viewport	22:26
22:44	JAC	Jennie, Masayuki, Rahul	LVEA	Y	JAC installation	Ongoing
22:52	CAL	Jeff	CER	-	Pictures of racks	22:59
22:56	SQZ	Sheila, Kar Meng	LVEA	Y	HAM7 SQZ beam alignment	00:04
22:59	CAL	Tony	PCal Lab	Local	Check measurement	00:16
23:13	JAC	Betsy	LVEA	Y	JAC installation	00:13
23:34	FAC	Tyler	LVEA	-	Checks	23:40
23:51	SQZ	Elenna	LVEA	Y	HAM7 SQZ beam alignment	00:04

LHO VE - X2-8 Ion Pump Out of Service

gerardo.moreno@ligo.org — Mon, 12 Jan 2026 14:02:52 -0800

Author: gerardo.moreno@ligo.org

Report ID: 88739

(Travis, Dave, Gerardo)

Dave noted and reported a rise on vacuum pressure at X-End. Since, Travis and I were in the control room, we quickly determined that the controller for X2-8 ion pump was not working. I drove down and found the high voltage disabled/off at the controller, and on on the screen the following note:"An excessive arcing condition has been detected (Error10)". No guidance found on manual, snapped a photo to submit later to vendor. I restarted the system and the HV started, controller hummed and crackled and was only able to get up to 600 Volts, all while making noise, and one point some funny smell came out of the inside of the controller, HV was disabled, time to replace the unit.

Images attached to this report

H1 PEM - Quarterly Dust Monitor testing FAMIS

ryan.crouch@ligo.org — Mon, 12 Jan 2026 13:09:24 -0800

Author: ryan.crouch@ligo.org

Report ID: 88737

Closes FAMIS#27662, previous check in alog84918. No new issues with any dust monitors.

**PSL Anteroom and Laser Room will be done at a later date when going in there is required for other tasks by Ryan Short.**

For the CS dust monitors.

LVEA:

HAM1 / LVEA5: On the +Y side of the HAM1 CR. Passed the zero count on the first round, and the flow was 2.8. PASS

HAM1: An additional spare DM on the -Y side of the HAM1 CR. Passed the zero count on the first round, the flow was a bit high at 3.0 so I adjusted it down to 2.8. PASS

HAM7 / LVEA6: Passed the zero count on the first round, and the flow was 2.8. PASS

Biergarten / LVEA10: Passed the zero count on the first round, and the flow was 2.8. PASS

DR: This DM was frozen when I got to it. Passed the zero count on the second round (first round had 2 cts of 0.3 um), and the flow was 2.8. PASS

Optics Lab: Passed the zero count on the first round, and the flow was 2.8. PASS

VPW: Passed the zero count on the second round (first round had 1 ct of 0.3 um), and the flow was 2.8. PASS

CER:

All the old grey HHPC handheld dust monitors in various states of degradation, none of them can take a full sample on power or battery without dying. I've removed the last one of this model I found in the CER and added it to collection of the other broken ones.

I tested the last spare GT521s left in the CER as well which I had borrowed from the FCES (s/n R16420). It passed the zero count test on the 2nd round (first round had 1 ct of 0.3 um) and the flow is 2.8. PASS

For the OUT building dust monitors.

EY: Passed the zero count on the second round (first round had 1 cts of 0.3 um), and the flow was 2.8. PASS

EX: Passed the zero count on the second round (first round had 1 cts of 0.3 um), the flow was a little low 2.65 so I went to adjust the pump in the mechanical room. These new vacuum pumps' adjustment knob seem touchier than the old one. It was at 19.5 inHg, I adjusted it up to 20 but it would stay at 20, it kept slowing increasing in pressure. I watched it slowly build up to almost 22 after I adjusted it up slightly to 20. I ended up bringing it back down to as close as I could get to where it was. I ended up around 19.8 inHg which brought the DM flow back to a little over 2.7, within the 5% margin of error. PASS

LHO VE - Mon CP1 Fill

david.barker@ligo.org — Mon, 12 Jan 2026 10:56:00 -0800

Author: david.barker@ligo.org

Report ID: 88738

Mon Jan 12 10:05:34 2026 INFO: Fill completed in 5min 30secs

Images attached to this report

LHO VE - Comment to Sun CP1 Fill, 10:00 fill did not run, manually ran a fill at 10:50

david.barker@ligo.org — Mon, 12 Jan 2026 08:11:05 -0800

Author: david.barker@ligo.org

Report ID: 88736

Monday's fill will also run with the elevated NOM_MAX=40C settings. Currently TC are [31C,34C].

LHO General - Ops Day Shift Start

ryan.short@ligo.org — Mon, 12 Jan 2026 07:45:30 -0800

Author: ryan.short@ligo.org

Report ID: 88735

TITLE: 01/12 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: 8mph Gusts, 4mph 3min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.59 μm/s
QUICK SUMMARY: JAC install and HAM7 alignment will continue today after craning finishes in the LVEA and it's transitioned back to laser hazard.

[Tagging SEI] The ETMX CPS glitched over the weekend, tripping both stages of the ISI, and I am unable to reset it without it tripping again immediately. Since ETMX isn't crucial for planned work today, I'll wait until Jim gets in and consult with him.

SEI

LHO VE - Sun CP1 Fill, 10:00 fill did not run, manually ran a fill at 10:50

david.barker@ligo.org — Sun, 11 Jan 2026 11:04:43 -0800

Author: david.barker@ligo.org

Report ID: 88734

Regularly scheduled fill at 10:00 did not run because both thermocouples were above the +30C nominal max limit [31C, 34C] presumably due to icing around the TC and/or Ref Junction.

Sun Jan 11 10:00:00 2026 ALARM: Abort run, Both Thermocouples BAD

I made a temporary change to the configuration to increase the nonimal TC-MAX to +40C and scheduled at 10:50 run.

Sun Jan 11 10:58:34 2026 INFO: Fill completed in 8min 30secs

This appears to be a good fill. The settings will be restored to nominal for tomorrow's fill.

Images attached to this report

LHO VE - Sat CP1 Fill

david.barker@ligo.org — Sat, 10 Jan 2026 10:53:27 -0800

Author: david.barker@ligo.org

Report ID: 88733

Sat Jan 10 10:09:50 2026 INFO: Fill completed in 9min 47secs

Images attached to this report