aLIGO LHO Logbook

LHO VE - Sat CP1 Fill

david.barker@ligo.org — Sat, 14 Mar 2026 10:24:31 -0700

Author: david.barker@ligo.org

Report ID: 89515

Sat Mar 14 10:14:30 2026 INFO: Fill completed in 14min 27secs

Images attached to this report

H1 IOO - JAC heater on

masayuki.nakano@ligo.org — Fri, 13 Mar 2026 23:37:41 -0700

Author: masayuki.nakano@ligo.org

Report ID: 89514

The JAC heater turned on at 8:00 PM PT. JAC-HEATER_POWER_SET is set to 3.

IOO, ISC

H1 General - OPS Friday EVE shift summary

ryan.crouch@ligo.org — Fri, 13 Mar 2026 19:56:37 -0700

Author: ryan.crouch@ligo.org

Report ID: 89510

TITLE: 03/14 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: I touched up DRMI alignment but we're still having issues with DC centering.
LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
23:24	Cheta	Sophie	Cheta Lab	local	Workign on Cheta	00:42
00:27	OPS	Oli	LVEA	LOCAL	Unplug laptop charger	00:33

01:20 UTC Oli and Jennie report that one of the light bollards in staging upper (the one closest to the stairs) shorted out, gave off a flash of light, a noise and started to lightly smoke. I informed Tyler who took a look using the remote cameras and determined its probably ok for the weekend, but he'll check up on it again.
While we were locked in DRMI I maximized the power with BS, PRM, and SRM. I was only really to make any gains with PRM_P.
"WFS DC centering railed" ISC_DRMI, I couldn't get the DC centering loops to turn on and stay on, PM1 was just railing constantly. I found an alog from Elenna with a possibly similar situation alog84782. The codes says its only checking DC1,2,3,4 at this stage and none of those are showing OUTPUTs greater than their LIMITS, only DC6 was showing OUTPUTs > LIMITS and the section of ISC_DRMI wfs_centering for REFL_AS should only check DC1,2,3,4, I'm not sure why its trying for DC6 (PM1?). I tried greatly reducing the gain, even setting it to zero for DC6 to no avail.
02:12 UTC I went DOWN and tried to come back up, it went quite quickly, ALS locked quickly on its own ( I reupped the gain on the TRX), IR went great then we locked DRMI within 3 minutes of entering the state ( I didn't raise any of the POPAIR or REFL RF gains) to get stuck by the WFS DC centering railed again. I now tried to reduce all the gains of the DC loops, turning DC6 to 0. After a few minutes ISC_DRMI was able to complete its DRMI_WFS_centering state that it had been stuck in, ISC_LOCK went into up to ENGAGE_ASC but we were constantly saturating RM1 with verbal calling out HTTS
02:35 UTC DRMI locked instantly this acquisition (without increasing the LSC gains again), I played with the gains on the DC loops, increasing DC2_Y from -3.5 to -4.0 allowing us to get past the centering, the RM1 HTTS sats started again after we entered ENGAGE_ASC until we lost lock when PRC1 started.
02:47 UTC DRMI unlocked, and I put us into IDLE for the weekend

Images attached to this report

H1 SUS - Comment to QOSEM Flag Gluing

thomas.roocke@ligo.org — Fri, 13 Mar 2026 19:12:45 -0700

Author: thomas.roocke@ligo.org

Report ID: 89513

The flag gluing yesterday was successful, with a strong joint and nothing obscuring the lens itself. We continued and glued another 6x flags up, and will do 6x more next week

Images attached to this report

LHO VE - HAM1 Pumpdown Update

gerardo.moreno@ligo.org — Fri, 13 Mar 2026 19:02:53 -0700

Author: gerardo.moreno@ligo.org

Report ID: 89511

Pumpdown continues on HAM1 and it is progressing. The chamber is currently being pumpdown with the SS500 cart aiding the turbo pump up on top of the chamber. We are very close to opening the ion pump for this chamber. Vacuum pressure is currently at 8.95x10^-07 torr. The aux carts to pumpdown the annulus for both chamber HAM1/2 were disconnected Monday, see aLOG entry 89440.

Images attached to this report

LHO VE - Test of Power Consumption of Y2-8 Ion Pump Controller

gerardo.moreno@ligo.org — Fri, 13 Mar 2026 18:34:54 -0700

Author: gerardo.moreno@ligo.org

Report ID: 89508

I used a power meter to measure the power consumption of a Gamma ion pump controller (Digitel MPCq type) to power the 1200 l/s ion pumps (this one located at Y2-8), I concentrated on startup of the controller, then on startup of the high voltage (7kV) for the ion pump..

During the initial startup of the ion pump controller the consumption goes up slow, it creeps up to 12.04 Watts max, then it drops a bit after. The second part of the test was to see the consumption spike when turning on the high voltage for the ion pump, for this test the meter immediately goes up to 40.69 Watts, then after a few seconds the power drops slowly.

A side effect of running this test can be appreciated on the attached trend data, because we powered off the ion pump the vacuum pressure internal to the main volume went up, it can be appreciated by the gauges along the Y-End station as well as Y2-8 gauge.

To do the test I powered the unit off and back on 3 times.

Images attached to this report

H1 ISC - PRMI locking today, DRMI also now locking

sheila.dwyer@ligo.org — Fri, 13 Mar 2026 18:07:05 -0700

Author: sheila.dwyer@ligo.org

Report ID: 89501

Sheila, Oli, Jennie, Tony, Ryan Crouch

Summary: Today we found that the 9MHz modulation depth was low because of a wrong setting, and that the beam was misaligned on the LSC REFLAIR A diode. After these changes and some gain adjustments we were able to lock DRMI.

Details:

After restoring the 9MHz modulation depth this morning (89497), we went on to locking PRMI, using the notes from 89491, but scaling for the increased modulation depth. Once it was locked, Oli and I went to ISCT1 to double check the alignment onto the POPAIR diodes, we slightly improved the alignment onto POPAIR A, but POPAIR B was already well aligned. We measured 0.55mW in the POPair path before the splitter using a power meter.

Oli phased POP18 + POP90 to maximize the I ERR signal with PRMI locked, and we put a 132 Hz, 3000 count exitation into PRM LOCK L to phase REFLAIR 9 and 45 to minimize the PRM signal in Q. (userapps/lsc/h1/templates/phase_REFLAIR.xml) We then adjusted the gain in REFLAIR 9 to match the ugf to the PRMI reference (screenshot). In O4, we used a whitening gain of 12dB and then a digital gain of 0.25 before the phase rotation, and LSC input matrix of 1.75 . Now we are using 30dB of whitening gain and a digitial gain of 4.4 to reproduce the same ugf (input matrix unchanged 1.75), so we are missing a factor of 140 signal strength compared to O4. For MICH the ugf is also right on the reference, screenshot. This is with 30dB of whitening gain and a digital gain of 4 before the phase rotation, compared with 0dB of whitening gain an a digital gain of 1 in O4, so this signal is too small by a factor of about 126. So this is pretty similar to the signal loss for REFLAIR 9.

Oli and I went back to ISCT1, removed the ND filter, and realigned reflair A. This gave us 2.5 counts on REFLAIR A LF, and we were able to relock PRMI with the whitening gains for REFLAIR back to normal. We adjusted the phase of reflair, and added some digital gains to set the ugfs to what they used to be.

A comparison time with PRMI locked in November 14th 2025, 22:23:00 UTC

	Nov 14th 2025 22:23 UTC PRMI locked	today PRMI locked	nov/now ratio taking gain changes into account
POPAIR A LF	~17 counts	16 counts	fine
POPAIR B LF	12 counts	8 counts	1.5
POPAIR B 18	100 counts, whitening gain 12dB, digital gain of 2	80 counts, whitening gain is 36dB, digital gain of 2	20 (improved with aligment)
POPAIR B 90	70 counts, whitening gain 6dB, digital gain 4	90 counts, 18dB whitening gain, digital gain 4	3
ASC POP X DC SUM	40 counts	-1	running raster on PM1
reflair A LF	2.5	2.5	after today's realignment
reflair B	5.5	5.3	yay?
reflair A RF9 signal	whiten gain of 12dB, digital gain of 0.25	whiten gain 12dB, digital gain of 0.31	1.25
reflair RF45 signal	whiten gain 0dB, digital gain 1	whiten gain 0dB, digital gain of 2.17	2.17

We ran SRY alignment manually, (the WFS don't work since we have not rephased them).

This screenshot shows the gains I had manually adjusted when we got a 3 second DRMI lock, March 13th at 23:28:21 UTC.

DRMI locking references: trigger levels: 44348 filter states and loop measurements: 87768 When DRMI grabs for a few seconds, it looses lock due to a 20Hz oscillation (screenshot), which suggests the MICH gain is too high. I tried a few changes to MICH gains. In this grabbing attempt, it seems that the MICH filter changes are what is making things unstable.

Edited to add: We have locked DRMI, with three manual changes, to the POP18 digital gain (set to 3 as in screenshot), RF9 gain set to 0.31, and RF45 gain set to 2.17. We think that this was too high for RF45, and instead it should be left as SDF will set it at 1. We stepped through the DRMI_locked guardian state manually which was fine.

Images attached to this report

H1 IOO - Added error message to JAC GUARDIAN for shutter

jennifer.wright@ligo.org — Fri, 13 Mar 2026 17:36:40 -0700

Author: jennifer.wright@ligo.org

Report ID: 89509

I added a check for the JAC shutter to the 'LOCKING' state to its guardian. This was because it was closed when the guardian was trying to lock JAC this morning and it took us a while to figure out.

We haven't had a chance to check this today due to efforts to lock DRMI but I will check it on Monday.

Its on lines 207-209 of the script.

if ezca['SYS-MOTION_C_SHUTTER_M_STATE'] != 0:#added to notify if shutter closed. J Wright 2026-03-13. notify('Shutter closed. Check shutter trigger values.') self.timer['waiting'] = 5

Thanks to Tony for helping me debug gedit.

H1 SUS - RM2 WD bypassed for now

oli.patane@ligo.org — Fri, 13 Mar 2026 17:11:36 -0700

Author: oli.patane@ligo.org

Report ID: 89507

Control room

RM2 SWWD has been bypassed temporarily until we offload some of it since we're near the end of the ADC range for one of the channels.

The ADC reaching the end of its range isn't what actually caused the trips though . The HAM1 ISI SW watchdog tripped after being triggered by RM2's LP SWWD. It looks like the LOCK filter bank integrators had started raking up counts, eventually causing large oscillations in the suspension that surpassed the LP SWWD threshold. The integrators for RM1, RM2, and PM1 all started building up at the same time, but for whatever reason the build ups on RM2 were much larger.

Jim says that he doesn't care for the HAM1 ISI whether any of the little tip tilts on there trip, so we're bypassing RM2 for now since its the closest to tripping.

CDS

LHO VE - Survey Of Site Cryopump's Pumpout Port

gerardo.moreno@ligo.org — Fri, 13 Mar 2026 17:06:16 -0700

Author: gerardo.moreno@ligo.org

Report ID: 89506

Took a picture of the pumpout port for each of the cryopumps.

The attached pictures below are from CP1 to CP8 from left to right.

Images attached to this report

H1 ISC - POPAIR and REFLAIR checks

jennifer.wright@ligo.org — Fri, 13 Mar 2026 17:04:57 -0700

Author: jennifer.wright@ligo.org

Report ID: 89503

Jennie W, Sheila D,

I compared the RF monitor values for POPAIR and REFLAIR LSC photodioes between today during state 51 "PRMI LOCKED" and 2026-11-14 22:28:00 UTC in state 50 "ACQUIRE PRMI".

Note we re-aligned both POPAIR B and REFLAIR A yesterday.

POPAIR A RF9 and RF45 have not changed much.

POPAIR B RF18 and RF90 have reduced a lot.

As have REFLAIR A RF9 and RF45.

REFLAIR B RF27 and RF135 have gone up instead of down which seems less worrying for locking purposes.

Name	14th Nov[dBm]	Today[dBm]	P_today / P_Nov
POPAIR_A_RF9	-54.8	-54.9	0.98
POPAIR_A_RF45	-54.6	-55	0.91
POPAIR_B_RF18	-49.6	-53.9	0.37
POPAIR_B_RF90	-46.9	-51.4	0.35
REFLAIR_A_RF9	-45.4	-55.4	0.1
REFLAIR_A_RF45	-37.5	-54.6	0.02
REFLAIR_B_RF27	-53.1	-50.0	2.0
REFLAIR_B_RF135	-30.2	-28.0	1.7

After this Oli and Sheila re-aligned REFLAIR A (detailed in Sheila's log 89501).

Images attached to this report

H1 CDS - SUS-AUX models' filter-module MEDMs now available

david.barker@ligo.org — Fri, 13 Mar 2026 16:53:06 -0700

Author: david.barker@ligo.org

Report ID: 89505

The SUS-AUX models have filtermodules, and until now the MEDMs for these have not been easily accessible.

With help from AI, I have written a python program which produces a set of MEDMs to permit navigation down the SUS-AUX tree to open MEDMs which display the filter modules.

To open the top level screen, which lists all the susaux models, a "SUSAUX Filters" button has been appended to the SUS pull down in the systems section of the SITEMAP (first attachment).

The second attachment shows the resulting FM screen when navigating from h1susauxb13 -> ITMX -> L2 -> NOISEMON

Images attached to this report

H1 General - Friday Ops Day shift report.

anthony.sanchez@ligo.org — Fri, 13 Mar 2026 16:43:51 -0700

Author: anthony.sanchez@ligo.org

Report ID: 89504

TITLE: 03/13 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: Ryan C
SHIFT SUMMARY:
The Commissioning crew today were focused on trying to get PRMI locked and stable for most of the day. Thye touched up the REFL A alignment which helped.
But there seems to be some power lost somewhere.

This spreadsheet was created to document the difference in the ratio of IMC Trans power/IMC input power back in the O4 run and now. Specifically when the PSL is set to 2 Watts. Feel free to update this in the future.

The Gain for H1:ALS-C_TRX_A_LF_GAIN has been bumped from 1.5 to 3 to get past FIND IR without issue.
This may not be the only gain that has been turnt to 11 to get DRMI to almost lock today, Sheila will be posting an alog later with some laser power acounting that may shed more light on that situation. Yes the Pun was intended.

LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
14:39	FAC	Randy	Xarm	N	Plowing the Tumbleweeds	17:02
15:06	H2O	Water contrators	Well	N	Testing the well water	18:06
17:04	VAC	Travis	Cleaning Racks & west bay, All ES and Mids	N	Looking for parts	19:34
17:26	FAC	Randy	LVEA	N	Walk about in the LVEA	17:49
18:28	PEM	Ryan	CER	N	Checking Dust mons	18:31
18:32	SPI	Jeff & Josh	Optics Lab	Yes	Working on SPI setup.	23:07
18:43	ISC	Sheila & Oli	LVEA	Yes	Tweaking alignments on ISCT1	19:09
18:50	OPS	LVEA IS Birfurcated HAZARD	HAM1	LOCAL	LVEA Bifurcated LASER HAZARD	11:29
19:37	EE	Marc	LVEA & CER	N	placing stickers and parts.	20:07
20:36	EE	Fil & Marc	Mid Y	N	getting cables.	21:14
20:49	VAC	Gerardo	EndY	N	Anulus ion pump controller testing, unplug replug	21:24
21:15	PEM	Ryan C	LVEA	N	chasing cables	22:25
23:24	Cheta	Sophie	Cheta Lab	local	Workign on Cheta	00:24

IOO, ISC

H1 General - OPS Friday EVE shift start

ryan.crouch@ligo.org — Fri, 13 Mar 2026 16:10:24 -0700

Author: ryan.crouch@ligo.org

Report ID: 89502

TITLE: 03/13 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: Tony
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 6mph Gusts, 4mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.21 μm/s
QUICK SUMMARY:

We've locked PRM a few times, working on aligning SRM / the SRC right now

H1 CDS - ndscope updated

erik.vonreis@ligo.org — Fri, 13 Mar 2026 12:34:41 -0700

Author: erik.vonreis@ligo.org

Report ID: 89500

There was a conda update on control room workstations to update ndscope from 0.20.7 to 0.20.8.

The new version fixes a bug where old data could be left on the plot when changing the time window if there was no data for that window from NDS. Thanks to Jenne for finding this bug.

It also fixes a bug where HDF5 and Matlab exports might be empty, and improves messaging around exports.

LHO VE - Fri CP1 Fill

david.barker@ligo.org — Fri, 13 Mar 2026 12:00:23 -0700

Author: david.barker@ligo.org

Report ID: 89499

Fri Mar 13 10:15:08 2026 INFO: Fill completed in 15min 4secs

Images attached to this report

H1 ISC - 9MHz modulation depth was low

sheila.dwyer@ligo.org — Fri, 13 Mar 2026 10:59:41 -0700

Author: sheila.dwyer@ligo.org

Report ID: 89497

Tony, Filiberto, Sheila, Jennie Wright, Oli

This morning we tried to do an OMC scan to check the modulation depths. The OMC high voltage was off, Filiberto found that the supply was powered on but the output disabled, so he enabled it.

We used 10W input power single bounce off ITMX. I compared this to a reference from 65828, it seems as thought the 9MHz is too small.

	April 2022	this morning (EOM driver 23.4dBm 9 Mz, 27dBm for 45MHz)	now (EOM driver 27dBm 9 Mz, 27dBm for 45MHz)	modulation depth now (calculated by Oli and jennie W)	modulation depth from April 2022 (alog 81816)
9MHz +/00 peak height	11.4e-3	5.04e-3	11.7e-3	.217	0.213
9MHz -/00 peak height	11.7e-3	5.4e-3	11.6e-3	.215
45MHz +/00 peak height	1.9e-2	1.7e-2	1.7e-2	.266	0.275
45MHz -/00 peak height	1.9e-2	1.7e-2	1.7e-2	.265

Jennie Wright checked modulation depths in 89456, at that time the EOM driver was set to 27dBm for 9MHz, on 10 am on March 10th it was set to 23.4dBm. This was in SDF as 23.4dBm, but this channel is not monitored and this table is not in SDF revert. ISC_LOCK prep for locking sets these values because they get changed in low noise, I've changed it in lsc params now.

Images attached to this report

H1 ISC - Comment to PRMI locked 1f using REFLAIR, many analog gains cranked up

sheila.dwyer@ligo.org — Fri, 13 Mar 2026 10:36:32 -0700

Author: sheila.dwyer@ligo.org

Report ID: 89498

I did a sneaky phasing of POP18 yesterday, by 180 degrees, to make the flashes positive.

H1 IOO - Comment to JAC work today summary

jennifer.wright@ligo.org — Fri, 13 Mar 2026 09:39:52 -0700

Author: jennifer.wright@ligo.org

Report ID: 89496

Here is the scan results pic which I forgot to include.

Images attached to this report

H1 General - Friday Morning shift report.

anthony.sanchez@ligo.org — Fri, 13 Mar 2026 07:44:56 -0700

Author: anthony.sanchez@ligo.org

Report ID: 89495

TITLE: 03/13 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: EARTHQUAKE
Wind: 5mph Gusts, 3mph 3min avg
Primary useism: 1.02 μm/s
Secondary useism: 0.21 μm/s
QUICK SUMMARY:

Site is wet, wind is low.
When I walked in there was an active 6.3M earthquake rolling through from Chile.
I'll give the earthquake about 10 more minutes to roll on through then start locking green arms and PRX for the comissioners.

LHO General - Thurs EVE Ops Summary

corey.gray@ligo.org — Thu, 12 Mar 2026 21:21:34 -0700

Author: corey.gray@ligo.org

Report ID: 89490

TITLE: 03/12 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: Corey
SHIFT SUMMARY:

Jenne/Jennies locked pseudo-PRMI earlier in the shift. Ran trend plots of sus for comparison between today and Nov2025 (see Jenne's alog).
LOG:

2346 Grabbing laptop (sophie)
0002 Jenne had PRMI locked for about a minute!
0318 Closed the HAM6 shutter due to OMC Trans increasing on nuc31

SUS

H1 ISC - Comment to Time of PRMI locked from Nov 16 2025

corey.gray@ligo.org — Thu, 12 Mar 2026 21:19:26 -0700

Author: corey.gray@ligo.org

Report ID: 89494

Here are comarison screenshots for the SUS Jenne mentions (skipped optional ones) between PRMI-locked-with-arms-held-off-resonance-state today and back in Nov2025. Comparisons are of upper mass OSEM's pit & yaw IN1 channels.

SUS

Images attached to this report

H1 ISC - Comment to PRMI locked 1f using REFLAIR, many analog gains cranked up

jennifer.wright@ligo.org — Thu, 12 Mar 2026 18:06:16 -0700

Author: jennifer.wright@ligo.org

Report ID: 89493

I used the lscparams to change the MICH triggers so I shave put these values back.

Below are OLG TFs I ran from userapps/lsc/h1/templates/PRCL and userapps/lsc/h1/templates/MICH

For PRCL the measurement is shown here where blue is the reference measurement in the tenplate, and red and green are the measurements I took today with different injection amplitudes.

We had to raise the injection in PRCL by a factor of 2.5 ti check the wiggles we can see in the gain between 10 to 30Hz are real.

Here is the measurement for MICH. Not sure we understand either of these yet. More investigation to come tomorrow.

Here is an ndscope with the 'good PRMI ACQUIRE time' we were using to scale gains and trigger levels. That is a prmi where we eventually locked and I picked the highest flash that occurred before we did.

Images attached to this report

H1 ISC - Time of PRMI locked from Nov 16 2025

jenne.driggers@ligo.org — Thu, 12 Mar 2026 17:52:27 -0700

Author: jenne.driggers@ligo.org

Report ID: 89492

It would be helpful to have a comparison of the top mass osem readbacks for optics, comparing this time in the attachment from Nov 15 2025, to tonight. In both of these times PRMI is locked with arms held off resonance with ALS (ISC_LOCK state 50).

Past time for comparison: 15 Nov 2025 00:26:00 UTC, plus or minus 1 minute (but check that ISC_LOCK_STATE_N was 50, and we want closer to the end time of that state 50 time).

Now time to compare: 2026-03-13 00:40:16.264360 UTC, plus or minus 10 mins.

Optics to trend:

IMs 1-4
RMs 1-2
PM1
MC1-3
PRM, PR2, PR3
BS
ITMs, ETMs, TMSs
others optional, like SR2, SR3, OMs1-3.

SUS

Images attached to this report

H1 ISC - PRMI locked 1f using REFLAIR, many analog gains cranked up

jenne.driggers@ligo.org — Thu, 12 Mar 2026 17:42:23 -0700

Author: jenne.driggers@ligo.org

Report ID: 89491

[Sheila, Jennie, Jenne, RyanS, Corey]

We have been able to get PRMI locked (with arms held off resonance using ALS). To do this we:

Increased POP18 analog whitening gain, and redid its dark offsets
Phased POP90 by -180 deg. RyanS noticed that POP90 was flashing negative, when it should have been positive. We realized that POP18 was fine because the RF9s didn't need rephasing with the new EOM, but the RF45s needed to be phased by 90 degrees, so the RF90 would need a 180 deg phase.
Increased REFLAIR_A_RF9 analog whitening gain. No dark offset change needed
Increased REFLAIR_A_RF45 analog whitening gain and adjusted dark offsets.
Took the ratio of REFLAIR RF peak heights now vs a time with the same IFO config on Nov 16th 2025, and increased the MICH and PRCL LSC input matrix values by those ratios.
Jennie calculated what the updated MICH LSC trigger thresholds should be, but with the whitening gain up on POP18 we ended up being okay with the default from guardian.

PRMI locked without too much fuss. Since we've effectively also increased the noise on the error signals, it's a bit delicate, and I lost lock twice while touching up alignment. The third lock I was able to go a bit slower when touching up BS and PRM alignment, and we've now been locked for more than 20 mins (aka infinity). Jennie is taking PRCL and MICH OLGs.

The attached image shows all the things that I had changed.

POP18 analog gain to 45dB
POP18 dark offsets
REFLAIR_RF9 analog gain to 36 dB
REFLAIR_RF45 analog gain to 30 dB
REFLAIR_45_Q to MICH input matrix element to 22.7 (5.6x times default of 4.0)
REFLAIR_9_I to PRCL input matrix element to 18.6 (10.6x times default of 1.75)

Nothing is in guardian (except maybe some trigger thresholds which should be reverted), and nothing is saved in SDF.

Images attached to this report

LHO General - Ops Day Shift Summary

ryan.short@ligo.org — Thu, 12 Mar 2026 17:05:59 -0700

Author: ryan.short@ligo.org

Report ID: 89489

TITLE: 03/12 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: Corey
SHIFT SUMMARY: More alignment work today to recover H1; see other alogs for more detailed accounts of the day, some of which will be posted after this one). This afternoon we are attempting to lock PRMI using the main locking steps in ISC_LOCK, which will give us a better sense of our overall IFO alignment. And it happened for just over a minute!
LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
14:44	FAC	Kim, Nellie	LVEA	N	Technical cleaning	15:46
15:05	FAC	Randy	LVEA	N	Walkabout	15:30
15:21	EE	Fil	LVEA	N	Cable dressing, equipment cleanup	18:06
15:31	AOS	Betsy, Randy	LVEA	N	Moving optics table	16:03
15:57	ISC	Sheila	LVEA	Local	Align ISCT1 REFL path	17:00
16:09	FAC	Kim, Nellie	LVEA	N	Technical cleaning	17:04
16:16	SEI	Jim	LVEA	N	Checking test stand	16:28
16:34	EE	Marc	LVEA	N	Cable dressing, equipment cleanup	18:06
16:46	SPI	Jeff	Optics Lab	Local	SPI characterization	19:16
17:01	SPI	Jim	Optics Lab	Local	SPI characterization	19:16
17:20	TCS	Sophie	Prep Lab	Local	CHETA table work	19:16
17:26	FAC	Randy	X-arm	N	Tumbleweed clearing	17:50
17:52	VAC	Travis	LVEA	N	Working on feedthru kits	18:11
17:53	ISC	Sheila	LVEA	Local	Align ISCT1 REFL	18:31
18:22	VAC	Travis	LVEA	N	Turn off HAM1 cleanroom	18:25
18:23	PEM	RyanC	CER	N	Looking at comtroller box	18:37
18:32	ISC	Sheila, Oli	LVEA	Local	ISCT1 REFL	20:29
18:48	VAC	Travis, Betsy	LVEA	N	Sorting parts kits (Betsy out @ 19:00)	19:09
19:44	SPI	Jeff	Optics Lab	Local	SPI characterization	23:16
19:47	AOS	Betsy	LVEA	Local	HAM1 viewport sighting	19:56
19:58	AOS	Jennie	Optics Lab	-	Looking for camera	20:22
21:29	ISC	Oli, Jennie	LVEA	Local	Checking beams on ISCT1	22:26
21:53	PEM	RyanC	CER	N	Plugging in DMs to comtrol box	22:36
21:57	ISC	Sheila	LVEA	Local	Checking beams on ISCT1	22:26
22:02	VAC	Travis	LVEA	N	Looking for parts	22:15
22:51	SEI	Jim	EY	N	Checking wind fence	23:07
23:12	TCS	Sophie	Prep Lab	Local	CHETA table work	00:05

LHO General - Thurs EVE Ops Transition

corey.gray@ligo.org — Thu, 12 Mar 2026 16:37:14 -0700

Author: corey.gray@ligo.org

Report ID: 89488

Crew continues recovery work as I walked in: they were working on a pseudo-PRMI and then moved on to CHECK MICH FRINGES. And allof this was after work out on the floor at ISCT1 (see 89485). Much calmer breezes.

Operational Note:

What we can do alignment-wise with ALIGN IFO: Green Arms, PRX_LOCKED (for PRM touch ups). But basically have issues for any IR cavities alignment-wise that need WFS at this point. (Some MICH & SRC states also work, but we don't need them at this point)

H1 SUS - QOSEM Flag Gluing

thomas.roocke@ligo.org — Thu, 12 Mar 2026 16:12:52 -0700

Author: thomas.roocke@ligo.org

Report ID: 89487

[Tom R, Ibrahim] We glued 6x of the QOSEM flags, attaching the lens (D2500277) to the aluminium body (D2500253). This was done using a jig (D2600054) to ensure the lenses were aligned to the body of the flag. We used EP30. Only a tiny drop of glue is required, and was applied directly to the lip of the body using a thin wire. The flags will be left to dry overnight before another batch of 6 will be glued.

Images attached to this report

H1 ISC - ISCT1 alignments

sheila.dwyer@ligo.org — Thu, 12 Mar 2026 15:54:41 -0700

Author: sheila.dwyer@ligo.org

Report ID: 89485

Oli, Sheila, Jennie Wright, Ryan Short, Jenne Driggers

Today we aligned the ISCT1 refl and pop paths. First, we remembered that both refl and pop are now on the same top periscope mirror: 84558. Then we realized that the RF signal from PRMI flashes on POPAIR A was unrelated to light on the diode, it didn't go away when we blocked the diode, closed the beam diverter or shutter, or increase when we did get beam on the diode.

We had a bit of difficulty aligning onto the pop diodes because PRMI flashes are infrequent. With 2W PRMI flashes right now, we have about 1/10th of the POPAIR B LF light we expect, and roughly similar low RF18 flashes.

H1 TCS - Comment to CHETA progress

sophie.muusse@ligo.org — Thu, 12 Mar 2026 15:17:28 -0700

Author: sophie.muusse@ligo.org

Report ID: 89484

As described above the beam was profiled with L2 at different displacements and w0 and z0 determined using a non linear fit. The q from the fit values was then propagated to the ITM and the beamsize at the ITM was compared to the model.

Displacement: 0.0 mm

X:
Fit converged: w₀=896.3+/-37.1 µm, z₀=528.0+/-47.8 mm, w_ITM= 58.14mm
Model: w0=1020.9 µm, z=725.22 mm, w_ITM= 52.26mm

Y:
Fit converged: w₀=977.3+/-40.1 µm, z₀=449.0+/-40.1 mm, w_ITM= 53.21mm
Model: w0=999.36 µm, z=458.67 mm, w_ITM= 53.00mm

Displacement: 50.0 mm

X:
Fit converged: w₀=794.4+/-25.4 µm, z₀=506.2+/-38.8 mm, w_ITM= 74.48 mm
Model: w0=818.78 µm, z=537.12 mm, w_ITM= 64.91mm

Y:
Fit converged: w₀=882.3+/-36.1 µm, z₀=465.0+/-44.9 mm, w_ITM= 65.7 mm
Model: w0=836.41 µm, z=358.2 mm, w_ITM= 63.24 mm

Displacement: -50.0 mm

X:
Fit converged: w₀=1164.2+/-38.2 µm, z₀=712.0+/-33.5 mm, w_ITM= 34.79mm
Model: w0=1321 µm, z=901.17 mm, w_ITM= 40.54mm

Y:
Fit converged: w₀=1117.9+/-49.5 µm, z₀=456.1+/-34.1 mm, w_ITM= 40.85mm
Model: w0=1214.4 µm, z=521.06 mm, w_ITM= 43.36mm

Images attached to this report

H1 ISC - Moved IMC uncontrolled degree of freedom, very subtle output pointing change

jenne.driggers@ligo.org — Thu, 12 Mar 2026 14:19:08 -0700

Author: jenne.driggers@ligo.org

Report ID: 89483

[Commissioners]

As yet another thing to try alignment-wise, I moved the IMC's uncontrolled alignment degree of freedom.

In the attached plot, the y-axis references are set from our Nov 16th, 2025 15:32:00 UTC reference time. During this time today PRX was locked, so the absolute values on the ASC POP QPDs aren't really comparable to the reference time, but since there was no PRX ASC, there should still be changes on the POP QPDs.

I moved MC1 (top left traces in attachment) temporarily to the top mass osem position from Nov 16th while IMC ASC DoFs 1,2,3 were all closed (with a little higher than normal gain) and indeed see that MC3 responds in the expected way for the uncontrolled DoF. For a reminder on the uncontrolled degree of freedom, I'm looking at Jeff's G1301131 page 23. I expect the sign of the yaw on MC3 to be the same as the sign on MC1 (and it is), and I expect the sign of the pitch motion on MC3 to be opposite of that of MC1 (and it is). So, I think that indeed I've moved the uncontrolled DoF (called DOF4 in that slide deck).

When the uncontrolled degree of freedom is moved, I'd expect the pointing of the beam coming out of the IMC to change (I have not calculated by how much). In the attachment, I see that IM4 trans indeed looks like it has moved by about 0.04 normalized counts. I don't see much change on POP A or POP B QPDs - if there's any change, it's extremely small.

Anyhow, I'm not sure there's anything deep here, but perhaps we could go back to this MC1 position from Nov 2025 and then move IM3 to get back to the reference position on IM4 trans and then move IM4 to get back to the reference position on POP QPDs, and see if that changes anything. We've moved more than this on the IM4 and POP QPDs already over the last few days, so I'm not sure that doing so will magically fix things.

Images attached to this report

LHO General - Comment to Wed EVE Ops Transition

corey.gray@ligo.org — Thu, 12 Mar 2026 12:59:45 -0700

Author: corey.gray@ligo.org

Report ID: 89482

Whoops! Looks like I was too focused on turning off excitations to post summary last night (left site at 8pmPDT). Summary:

TITLE: 03/11 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:
It's been mentioned earlier, but it sounds like there are issues with beams observed on some in-vac sensors, but not on others. This evening I attempted a test commissioners mentioned as they left in the evening: drive RM1 & RM2 at a low frequency and see if one can see anything on ASC REFL A (& B). Made an attempt at this, but not sure my set up was optimal. Turning OFF the excitations before I leave (RM1 & RM2 were driven from roughly 2-3utc---with tests in the hour or two before that).

Very windy night!

LVEA: Operations SAFE (with South Bay signs saying Laser SAFE)
Optics Lab: SPI laser is on in the optics lab with curtains closed & "laser unattended" chain up overnight

LOG:

Power supply checks completed during my handoff from RyanS (daniel.jenne.jennie)
out @2350 Collecting connectors in Prep Lab (sophie)
done at 0038 Checking cryopumps down the x&y arms (gerardo)
out @2352 for BHD work in Optics Lab (oli)

LHO VE - Thu CP1 Fill

david.barker@ligo.org — Thu, 12 Mar 2026 10:36:24 -0700

Author: david.barker@ligo.org

Report ID: 89481

Thu Mar 12 10:14:28 2026 INFO: Fill completed in 14min 24secs

Images attached to this report

H1 CDS - Comment to JAC Camera added to CDS.

david.barker@ligo.org — Thu, 12 Mar 2026 08:25:25 -0700

Author: david.barker@ligo.org

Report ID: 89480

Note IOT1 JAC cameral epics channels are not currently being trended by the DAQ. We will schedule a DAQ restart to add its INI file to the EDC.

H1 CDS - Mains power glitches Wednesday night

david.barker@ligo.org — Thu, 12 Mar 2026 08:13:16 -0700

Author: david.barker@ligo.org

Report ID: 89479

We had a couple of power glitches last night, reported by the GC UPS briefly going onto battery power (no reports from CDS UPS)

Both were very brief, 4 or 5 cycles in duration, impacting all 3 phases.

18:16:15 Wed11Mar2026 PDT

21:26:26 Wed11Mar2026 PDT

No sign of any impact on CDS, also HEPI pump controllers look good.

Images attached to this report

LHO General - Ops Day Shift Start

ryan.short@ligo.org — Thu, 12 Mar 2026 07:38:51 -0700

Author: ryan.short@ligo.org

Report ID: 89478

TITLE: 03/12 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: 31mph Gusts, 20mph 3min avg
Primary useism: 0.06 μm/s
Secondary useism: 0.32 μm/s
QUICK SUMMARY: Very windy night with gusts over 50mph, but expected to calm down slightly as the day goes on. Will continue with IFO recovery and beam hunting today.

H1 ISC - Comment to Locking Notes - Wednesaday 11th March

jennifer.wright@ligo.org — Wed, 11 Mar 2026 22:01:11 -0700

Author: jennifer.wright@ligo.org

Report ID: 89476

Jennie, Jenne, Sheila, Daniel, Ryan S, Corey,

Summary: We can align the x-arm with IR but not get good signals on several of our HAM1 in-vac sensors, even after several rounds of RM, IM and PR mirrors moves.

We tried going back to the baffle align scripts and this brought us to a different X-arm alignment. In this new alignment we still could not see reasonable signals on LSC-POP_A PD (factor of 10 too small) or ASC-REFL_A and B (signals were a factor of 1000 too small). By 'reasonable' I mean compared to the level at our reference time of 15:32:00 UTC on November 16th. We chose this instead of the time on December 12th that we used as a reference in yesterday's locking efforts as it is before the site power outage which happened on December 4th.

Some things we ruled out:

Moving PM1 around the whole range of pitch and yaw adjustment does not help us get signals on LSC-POP_A. So even if this somehow moved during the vent (since to reach JAC path optics one must lean over it) this makes that seem unlikely. The close out transfer functions for PM1 were also within nominal parameters so we think its unlikely the BOSEM swap out or any of the coil driver problem solving that happened for that suspension.
HAM1 periscope that delivers the POP and ALS beams to HAM1. Since we can get good beat notes for ALS signals on ISCT1 it seems unlikely this moved during the vent when stiffeners were added to it.
On the REFL side of the table (-Y) side. It seems weird that we can get good signals on LSC-REFL PD but not on the WFS (these are a factor of 1000 too small). These share most of the path from HAM3. Corey ran some injections on both RMs tonight which we can check in the morning to see if there is some alignment of them that makes ASC-REFL A and B signals go back to reasonable levels.
Yesterday Jenne found if she mis-aligned PRM we could get reasonable signal levels on ASC-REFL_B. So we don't think it is an electronics issue.

Just to double check - Jenne, Daniel and I went to the racks by ther PSL to check that the WFS electronics chassis were turned on. Everything looks good and Daniel checked the power connection to each box was not falling out.
- LSC rack r4, u37 holds the DC refl and pops wfs electronics, this seems fine and is powered.
- We also checked R1 and R2 racks that hold the RF and everything seems powered and plugged in.

Daniel also checked that none of the HAM1/3 pico motors had been used since the vent started. This is pico controller A. The only use was earlier today when we tried to improve the pointing from hAM3 to the LSC POP diode but Sheila already undid this.

Jenne also checked the uncontrolled degree of freedom in the mode cleaner (MC2 + MC3) by moving MC1 to its old position from November and letting the WFS move MC2 and MC3. This also did not help.

I checked with Jim (who unlocked HAM1 HEPI earlier today) that HAM1 and 3 should not have moved since November. Both of these should be fine as HAM3 HEPI was never locked during the vent and HAM1 HEPI has not moved appreciably in the DOFs that would affect alignment.

H1 ISC - Comment to Locking Notes - Wednesaday 11th March

sheila.dwyer@ligo.org — Wed, 11 Mar 2026 21:35:16 -0700

Author: sheila.dwyer@ligo.org

Report ID: 89477

In the afternoon we observed that with PRX fringing, we can see a signal on LSC POP A RF45 that is about 1/10 of what it was in this state in November. We saw that this amplitude did not change when we moved PM1 acros it's full acutation range. We used the PR2 spot move guardian state to keep PRX aligned while we moved PR3 by several microradians, and this also did not change the amplitude on LSC POP RF45. We then redid the baffle PD scripts, which resulted in ITM alignments different by 3-4urad at most, and realinged the vertex to those ITMs. This didn't change the situation of missing signals in the in vacuum pop or the REFL WFS. We do see that we have 3-4 counts on both REFL ASC sensors with 2W incident on PRM now, compared to 3-4 thousand counts in November.

These various efforts leave me thinking that the problem isn't an interferometer alingment problem, but could be an issue with the PDs or electronics, or alignment in HAM1.

We can see the expected light level on both LSC refl diodes for most of these alignments, and we can see clear signals in the POP air diodes, although we haven't aligned those and the signal levels seem a bit small compared to November. While we could proceed with locking with the reflair and popair diodes, we also need to figure out what is happening with the in vacuum diodes.

H1 TCS - CHETA progress

sophie.muusse@ligo.org — Wed, 11 Mar 2026 19:55:17 -0700

Author: sophie.muusse@ligo.org

Report ID: 89475

S. Muusse

Calibrating sensors

I have been working on calibrating the sensors on the cheta tables. When calibrating the power at the pick off that will be used to monitor CHETA power on ITM using beckhoff I was seeing voltage jumps up to saturation at 2.5V as shown in attached plot. This was determined to be due to the auto range on the thermal power head being on. This setting was turned off ( as outlined in T2600081 ) and a range of 0-22mV was selected as max incident power was ≈ 11mV. After which a linear relationship was observed and shown in the attached plot. The laser power vs laser current and the measured V vs laser current have been takem but I havent calculated the responsivity value for the beckhoff screen yet.

Profiling CHETA beam

The beam profiler has been shipped back from LLO to check the alignment against the model and profile the beam size as the second lens is moved by the translation stage. This is how we aim to control the CHETA beam size.
On the Y-table the beamsize was measured over a 60mm distance and the profile was fit with a non linear fit for w0 and z0 setting M2 =1. This is shown in the attached plot.

--- Horizontal (A1) Fit ---

Fit converged: w₀=896.3+/-37.1 µm, z₀=-528.0+/-47.8 mm

Model: w₀=1020.9 µm, z₀=-704 mm

--- Vertical (A2) Fit ---

Fit converged: w₀=977.3+/-40.1 µm, z₀=-449.0+/-40.1 mm

Model: w₀=999.36 µm, z₀=-459 mm

The vertical fit agrees for both w0 and z0 within the fit uncertainties and the horizontal profile was just outside the uncertainty bounds.
Subsequently, the beamsize has been measured along the same positions with L2 at its minimum and maximum displacements on the translaiton stage (±50mm) but this data hasnt been processed yet at will be added in a comment.

Images attached to this report

LHO General - Ops Day Shift Summary

ryan.short@ligo.org — Wed, 11 Mar 2026 16:52:51 -0700

Author: ryan.short@ligo.org

Report ID: 89473

TITLE: 03/11 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: Corey
SHIFT SUMMARY: Busy day of IFO recovery, mostly in the form of hunting for beams and putting them in their appropriate places. See alogs from others for more detailed accounts of the day (such as alog89469). The wind has been picking up and doesn't look to be calming down until tomorrow, which has been making locking the arms difficult when desired.
LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
14:45	FAC	Kim	Optics Lab	N	Technical cleaning	14:55
15:09	FAC	Kim, Nellie	LVEA	N	Technical cleaning	15:56
16:42	SEI	Jim	LVEA	N	Unlocking HAM1 HEPI	16:53
17:04	TCS	Sophie	Prep Lab	Local	CHETA work	19:46
17:04		Betsy	Optics Lab	Local	Looking at parts	17:24
18:08	ISC	Oli	Optics Lab	-	BHSS work	19:46
18:26	SPI	Jeff	Optics Lab	Local	SPI characterization	23:04
19:08	ISC	Jennie	LVEA HAM1	LOCAL	Take pictures by HAM1	19:13
20:53	SEI	Jennie	Optics lab	LOCAL	SPI	21:14
21:49	CDS	Fil, Marc	LVEA	N	Looking at network cables in susrack	22:07
22:56	ISC	Daniel, Jenne, Jennie	LVEA	N	Checking power supplies	23:39
23:02	VAC	Gerardo	LVEA	N	Taking pictures of cryopumps	23:25
23:06		Camilla +1	LVEA	N	Family tour	23:29
23:10	TCS	Sophie	Prep Lab	Local	Collecting connectors	23:50
23:25	VAC	Gerardo	Mids, Ends	N	Looking at cryopumps	Ongoing

LHO General - Wed EVE Ops Transition

corey.gray@ligo.org — Wed, 11 Mar 2026 16:37:55 -0700

Author: corey.gray@ligo.org

Report ID: 89471

TITLE: 03/11 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 41mph Gusts, 30mph 3min avg
Primary useism: 0.10 μm/s
Secondary useism: 0.31 μm/s
QUICK SUMMARY:

Got an overall summary on the status of H1 recovery from RyanS.

H1 CDS - JAC Camera added to CDS.

david.barker@ligo.org — Wed, 11 Mar 2026 16:13:49 -0700

Author: david.barker@ligo.org

Report ID: 89470

Fil, Patrick, Jonathan, Erik, Dave:

Fil connected the IOT1 JAC digital camera to the CER POE switch (sw-lvea-aux 0/4).

Erik added the new camera to DNS as h1cam38 (10.106.0.61).

Patrick added this camera as the first cam on h1digivideo6, using the multicast address 239.192.106.67

I added the camera to camera.yaml and updated the camera overview MEDM (see attached).

The camera is currently in a dark location, so no image.

Images attached to this report

H1 ISC - Locking Notes - Wednesaday 11th March

camilla.compton@ligo.org — Wed, 11 Mar 2026 11:55:31 -0700

Author: camilla.compton@ligo.org

Report ID: 89469

Sheila, Ryan S, Jennie, Jenne, Control Room...

Ryan started with green initial alignment and got PRX locked 69467.

Sheila continued yesterdays work looking for signals in the REFL path. Could again get signal on ASC REFL B but not A. She measured PRX OLG, see attached, it's a bit below the reference.

Sheila reset the LSC POP A 45 dark offsets that are hard coded in ALIGN_IFO PREP XARM state.

Sheila set up some sine oscillations on PM1 and RM2 to try to find the beam on the POP diodes in HAM1.

Jennie/e and I then reset IM1,2,3,4 to a November time 2025/11/16 15:34:24 UTC (ndscope on cdsws44 had some issues with this yesterday). And then we walked IM3 and IM4 to get IM4_TRANS and ASC-POP_A back to this time which was quite different IM3/4 alignments. ASC-POP_B ended up not too far off. Plot of now and November attached. In particular, IM3 and IM4 PIT OSEMs are 200 and 400urad different than November.

Ryan and Jenne improved Xarm IR transmission via PR2.

Images attached to this report

LHO VE - Wed CP1 Fill

david.barker@ligo.org — Wed, 11 Mar 2026 10:38:57 -0700

Author: david.barker@ligo.org

Report ID: 89468

Wed Mar 11 10:03:46 2026 INFO: Fill completed in 3min 44secs

Quick fill, LN2 was burping after yesterday's fill for a few hours.

Images attached to this report

LHO General - Ops Day Shift Start

ryan.short@ligo.org — Wed, 11 Mar 2026 07:38:25 -0700

Author: ryan.short@ligo.org

Report ID: 89467

TITLE: 03/11 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: CALM
Wind: 21mph Gusts, 16mph 3min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.33 μm/s
QUICK SUMMARY: Breezy night with a few small earthquakes rolling through. More alignment work today, and the IFO right now is DOWN, but I'll start with a fresh ALS alignment of the arms then go into BS and possibly PRX alignment (I'll see how far I get) to give us a good starting place to go from today. In other news, the JAC and IMC stayed nicely locked overnight except for one dropout when an earthquake hit.

H1 General - Tuesday Eve Shift Report Update

anthony.sanchez@ligo.org — Tue, 10 Mar 2026 18:29:12 -0700

Author: anthony.sanchez@ligo.org

Report ID: 89466

TITLE: 03/11 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:
Comissioning team is leaving the IFO in Down tonight due to mis alignment somewhere between the Power recycling cavity and JAC ~ 1:25 UTC.

H1 ISC - Comment to Locking Notes - Tuesday 10th March

jenne.driggers@ligo.org — Tue, 10 Mar 2026 18:18:15 -0700

Author: jenne.driggers@ligo.org

Report ID: 89465

After Jennie put IM2 back to where it had been, we re-moved IM3 to get roughly back to where we'd been on IM4 trans, and then IM4 to get back to where we'd been on ASC POPA and POPB QPDs.

We could then move PRM to align PRX, and lock PRX just fine. However, we still don't have any significant signal on the ASC REFL WFS. RyanS noticed that when we were re-aligning PRM, that we'd get a flash of light on ASC REFL B. So, we moved PRM around and found that we can get a good amount of light (almost 4000 counts) on ASC REFL B with an offset on PRM of -1000 counts in yaw. This is a *huge* number, so something is clearly wrong with the pointing of our incoming beam. We could get a bit of light on ASC REFL A, but only as much as ~4 counts (so, 1000x too small) no matter how much we moved PRM, RM1, and RM2. The RMs we moved until they were saturating, so it's not their fault - there's just something we don't understand yet about the input pointing.

One thing this means (among other reasons we're not powering up yet) - we want to hold off on going to more than 10W or so until we're sure that the PRM refl beam is going to be hitting the porcupine beam dump on top of HAM2.

(Sheila has some other notes on other things we did today).

Next steps: *shrug*. We're pretty sure that all of the input pointing optics are back to where they were in ~Dec. The IMC is aligned to where it had been, via the WFS and centering on MC2 trans, so we're probably fine up to there. Anyhow, next steps are still figuring out where our REFL and POP beams are going, since it's not to the PDs.

H1 SUS - BHSS / BHD work March 09 / 10

oli.patane@ligo.org — Tue, 10 Mar 2026 17:53:57 -0700

Author: oli.patane@ligo.org

Report ID: 89463

Camilla, Betsy, Oli

We've made some good progress the last couple of days for the BHSS.

Yesterday I moved the four tiny BHSS beam dumps onto the center of the BHSS next to the BHSS optics. I then carefully wrapped up the BHD sled and table optics mounts (who still don't have optics in) to make some more space on the table. Each mount was gently double wrapped individually in foil, with the mounts with black glass being covered with an optics cloth. Then I grouped and wrapped everything into four big packs: sled lens mounts, sled mirror mounts, table lens mounts, and table mirror mounts. These packs were put aside and left a lot more room on the table. Tomorrow we will double bag and label them to get them off the table.

This morning Betsy and I went into the Triples Lab and glued the viton tips to the OMC cradles and the screws, and those are in the oven and will be taken out tomorrow morning.

Yesterday I also discovered that the BHSS Alignment Tooling Plate (D2400074) needed to be helicoiled, so today I helicoiled it and then put it together on the BHSS. After installation, I needed to remove it and the supporting posts (D2400117), and when trying to reinstall the posts I discovered that one had been gouged and I couldn't get the screws in very far. I was able to get a screw in the other post (proving that it wasn't the screw), and then this post also got messed up. I ended up just standing one of the support posts under where it needed to be. The other post was too loose under the tooling plate (we probably need to loosen a couple of the earthquake stops on one side of the BHSS), so Camilla jigged up a washer + longer set screw combo that held onto the plate and the little amount of the post that wasn't messed up.

We turned on the laser and measured the power before and after the fiber. Before the fiber was 4.5mW and directly after was 1.83mW. With this power we did some rough beam alignment and were successfully able to get the beams to the second iris along each path (layout pic). Tomorrow we do fine-tuning.

ISC

Images attached to this report

H1 ISC - Comment to Locking Notes - Tuesday 10th March

jennifer.wright@ligo.org — Tue, 10 Mar 2026 17:53:25 -0700

Author: jennifer.wright@ligo.org

Report ID: 89464

I put IM2 and 3 back to their values on the 12th December when we were doing manual initial alignment.

LSC_POP_A and LSC_REFL_A were close to their values on 12 December (when ALIGN_IFO was in state 35). I put the RM 1 and 2 mirrors back to there values at this reference time also.

Images attached to this report

H1 General - Tuesday Eve Shift Report

anthony.sanchez@ligo.org — Tue, 10 Mar 2026 17:43:43 -0700

Author: anthony.sanchez@ligo.org

Report ID: 89462

TITLE: 03/10 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 17mph Gusts, 13mph 3min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.29 μm/s
QUICK SUMMARY:

There is a concentrated effort to integrate & align JAC into the IFO.
Camilla wrote up some quick locking notes up to 00:00 UTC

Currently working out PR alignment.

LHO VE - Update On Purge Air Compressor

gerardo.moreno@ligo.org — Tue, 10 Mar 2026 17:25:08 -0700

Author: gerardo.moreno@ligo.org

Report ID: 89460

(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

H1 ISC - Locking Notes - Tuesday 10th March

camilla.compton@ligo.org — Tue, 10 Mar 2026 17:00:42 -0700

Author: camilla.compton@ligo.org

Report ID: 89448

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.

Images attached to this report

H1 IOO - IM1 and 2 today compared to December 12th

jennifer.wright@ligo.org — Tue, 10 Mar 2026 16:46:27 -0700

Author: jennifer.wright@ligo.org

Report ID: 89461

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.

IOO

Images attached to this report

H1 General - OPS Monday Day Shift Summary

ryan.crouch@ligo.org — Tue, 10 Mar 2026 16:36:03 -0700

Author: ryan.crouch@ligo.org

Report ID: 89446

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:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
15:09	FAC	Nellie	MidY	N	Tech clean	15:30
15:28	ALS	Sheila, Camilla	LVEA	LOCAL	ISCT beatnote alignment, Camilla turn on CO2 and SQZ lasers	16:07
15:54	FAC	Kim, Nellie, Randy	LVEA	N	Move clean room, N bay to W bay, K/N out 16:19UTC	16:42
15:56	BHD	Oli	Optics lab	LOCAL	Parts search / checks	16:26
16:09	FAC	Tyler+Contractors	Site	N	Fire inspections	20:36
16:21	EE	Marc	CER	N	Check on cables, measure video cable	17:12
16:43	FAC	Randy	EndY	N	Checks	17:13
16:52	SEI	Jeff	Optics lab	LOCAL	SPI	19:24
17:02	BHD	Oli	Optics lab	LOCAL	Helicoil HXDS alignment tooling	17:52
17:15	EE	Marc	Mech room	N	Turn on SQZ HV	17:21
17:20	FAC	Eric	OSB	N	Shut off AH 4 - offices	17:38
16:40	FAC	Kim	HAM Shaq	N	Tech clean	17:23
17:23	FAC	Kim	MidX	N	Grab supplies	17:45
17:27	TCS	Sophie	Prep lab	N	CHETA work	19:32
17:30	ISC	RyanS, Jennie	LVEA	LOCAL	HAM1 JAC table work	18:50
17:45	FAC	Kim	EndX	N	Tech clean	18:45
18:04	EE	Marc	LVEA	LOCAL	Check on JAC cable	18:18
18:39	SEI	Jim	LVEA, then optics	N	HAM6, move parts to optics lab	18:50
19:04	ICS	Sheila, Jennie, RyanS	LVEA HAM1	LOCAL	JAC work	19:17
19:41	ISC	Sheila, RyanS	LVEA HAM1	N	JAC table measurements	19:52
19:55	FAC	Kim	LVEA	N	Stock garb	20:28
20:27	BHD	Oli	Optics lab	LOCAL	BHSS work	Ongoing
20:31	EE	Marc	MidY	N	Get cables	21:30
20:36	FAC	Tyler	Beamtube	N	Install new speed limit signs	21:36
21:00	VAC	Jordan	LVEA, Ybeam manifold	N	Anulus ion pump troubleshooting	21:48
21:28	ISC	Jennie	LVEA	LOCAL	ISCT1 table beam check	21:48
22:08	SEI	Jeff	Optics lab	LOCAL	SPI	23:12
22:17	BHD	Camilla	Optics lab	LOCAL	BHSS	Ongoing
22:48	TCS	Sophie	Prep lab	N	CHETA work	Ongoing

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.

H1 IOO - IMC ASC DOF3 using JM3

sheila.dwyer@ligo.org — Tue, 10 Mar 2026 16:00:37 -0700

Author: sheila.dwyer@ligo.org

Report ID: 89459

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.

IOO

Images attached to this report

H1 SQZ - SQZ Notes, Laser back on, tempurature adjusted for coaligned red and green, Can't lock OPO with CLF yet.

camilla.compton@ligo.org — Tue, 10 Mar 2026 15:07:16 -0700

Author: camilla.compton@ligo.org

Report ID: 89453

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.

Images attached to this report

H1 IOO - Comment to Improve IMC WFS RF phasing

sheila.dwyer@ligo.org — Tue, 10 Mar 2026 14:53:29 -0700

Author: sheila.dwyer@ligo.org

Report ID: 89458

I made a template to check this phasing, it's in userapps/ioo/h1/dtt/IMC_wfs_phase.xml

Also, we used to use LSC_EXTRA_AO_2 for putting excitations into the common mode or IMC board, that channel still exists but it is now used for JAC locking. So, instead we should use EXTRA_AO_3 from now on.

Images attached to this report

H1 IOO - Improve IMC WFS RF phasing

daniel.sigg@ligo.org — Tue, 10 Mar 2026 14:49:42 -0700

Author: daniel.sigg@ligo.org

Report ID: 89457

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

Attached: screenshot of new values and spectra.

Images attached to this report

Non-image files attached to this report

imc_wfs_260310_C-rotated90.pdf

H1 IOO - Modulation depths with new vs. old eom

jennifer.wright@ligo.org — Tue, 10 Mar 2026 14:25:32 -0700

Author: jennifer.wright@ligo.org

Report ID: 89456

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).

ISC

H1 PSL - PSL Weekly Status Famis Report

anthony.sanchez@ligo.org — Tue, 10 Mar 2026 13:59:31 -0700

Author: anthony.sanchez@ligo.org

Report ID: 89455

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

H1 General - Comment to Locking Notes - Monday 9th March - IMC now locks

sheila.dwyer@ligo.org — Tue, 10 Mar 2026 11:06:01 -0700

Author: sheila.dwyer@ligo.org

Report ID: 89452

The UGf that Camilla posted above (38.5kHz, with 2W input power before JAC and 5dB gain on IMC IN1) implies that the modulation depth for the IMC is about the same or slightly higher than it was before the JAC installation. See 89046 which was before the EOM crystal swap).

LHO VE - Tue CP1 Fill

david.barker@ligo.org — Tue, 10 Mar 2026 11:03:02 -0700

Author: david.barker@ligo.org

Report ID: 89451

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

Images attached to this report

H1 ISC - Inspected Jack Screws SUS C1 - SUS C4

marc.pirello@ligo.org — Tue, 10 Mar 2026 10:39:06 -0700

Author: marc.pirello@ligo.org

Report ID: 89450

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

SUS

H1 ISC - Turned on HV for SQZ HAM7

marc.pirello@ligo.org — Tue, 10 Mar 2026 10:28:52 -0700

Author: marc.pirello@ligo.org

Report ID: 89449

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

SQZ

H1 TCS - Turned on SQZ laser, CO2 lasers and TCS Sleds.

camilla.compton@ligo.org — Tue, 10 Mar 2026 09:13:36 -0700

Author: camilla.compton@ligo.org

Report ID: 89447

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

SQZ

H1 AOS - OPS Tuesday day shift start

ryan.crouch@ligo.org — Tue, 10 Mar 2026 07:33:44 -0700

Author: ryan.crouch@ligo.org

Report ID: 89445

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!

H1 CDS - Workstations were updated

erik.vonreis@ligo.org — Tue, 10 Mar 2026 07:16:57 -0700

Author: erik.vonreis@ligo.org

Report ID: 89444

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

LHO General - Mon EVE Ops Summary

corey.gray@ligo.org — Mon, 09 Mar 2026 19:08:27 -0700

Author: corey.gray@ligo.org

Report ID: 89442

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.

H1 ISC - Comment to Green arms aligned!

corey.gray@ligo.org — Mon, 09 Mar 2026 19:02:49 -0700

Author: corey.gray@ligo.org

Report ID: 89439

(jenne, ryanS, corey)

NOTES on Green Arm Alignment Recovery After Gate Valves Opened on Mar 5, 2026 for Jenne & Corey (Using Sheila/TJ notes as a reference and adding notes for what was done 3/5/26).

After closing gate valves, alignments tend to shift making recovery harder. In the corner station, the ITM camera pointing will shift enough to make the camera offsets unusable. Sheila posted instructions on how we should recover this in alog88346, detailed below.

= Instructions =

Do Initial Alignment WITHOUT using green cameras in the loop, as the cameras are right next to the gate valves and have now been jostled around and have lost their previous reference history. (The camera references are very touchy to any movements/bumps anywhere near them!)
- Open INIT_ALIGN.adl (On Sitemap/ASC/Init Align)
- On the Scopes drop-down, open the X & Y Arm Baffle PDs scopes
- With SUS Guardians, MISALIGN the ITMs & ETMs
- On the Dither Align Scripts X & Y Arm Drop Downs, select TMSx & TMSy (they can both run at the same time & you can monitor their progress via their ternimals). These scripts are done when the terminal notes a successful completion. TMS scripts completed successfully (but did not see spots on the ASLx & ALSy cameras).
- Moved on to ITMs (took ITMx/y to ALIGNED state). Opened the (x & y) arm Baffle PD scopes, and then ran the Dither Align Scripts for ITMx & ITMy. (Once these scripts are successful, we will then try not to touch the ITMs any more.)
- ITMx finished successfully
- ITMy did not. Jenne trended the BS & ITMy and took them to previously good alignment (~85 days ago)--mostly yaw for both. Still did not see spots on the ALS x & y cameras!
  - Started to look at PR3, but Jenne noted we generally do not want to touch the pointing on PR3.
  - Went out to ISCT1. AND discovered that the Shutter ("ISCT1 ALS cavity beams") was CLOSED! NO Changes made on ISCT1! Returned to the Control Room since we now had a beam to work with!
- Temporarily touched PR3 to center spot on the ALSx camera (reverted later).
  - Touched TMSx, ETMx (NOT ITMx) to get something on the camera. Spot looked like a "coffee bean" spot....started to revert PR3...AND, the spot looked much better.
  - Went to LOCK ALSx and it immediately locked up on a 00!
- Selected LOCKED_SLOW_WFS_ETM_TMS state for ALS_XARM (this does not use cameras), but WFS weren't happy....but (ryanS noticed) this was because the guardians were stalled. Needed to push AUTO & this cleared the STALL on Guardian.
  - Touched ETMx & TMSx (mostly in yaw) & then went for LOCKED_SLOW_WFS_ETM_TMS again, and this time WFS took Xarm to ~1.
- After PR3 was restored (its yaw), went to ETM_TMS_WFS_OFFLOADED and ALSx was good.
- On To The ALSy
- Didn't have ASAIR video to look at due to no beam getting through JAC
- Trended BS sliders, osems, oplev and found good values ~85 days ago right after a Manual Initial Alignment
- Tweaked BS while looking at camera (and a previous good spot)---did not see anything on the camera
- Increased ALSy camera exposure & eventually saw a spot (actually two [thought it could be ALSx---so unlocked X-arm & closed the "ISCTEX green beam" shutter). But still saw both spots--so the two spots were Y-Arm!
- Move ETMy to get the two spots on top of each other and then Jenne eventually got a great spot.
- Around this point, a polarization error was noticed on guardian; RyanS mentioned the CHANGE POL guardian state can take care of this. So this was selected for ALS x&y.
- Returned to touching up y-arm w/ ETMy, TMSy
- Jenne mentioned, "Y-arm is finicky, and" you need its flashes close to 1. (we were around 0.6)
- Took a break & switched to BS moves in yaw and then returned to "cavity alignment" (ETMy/TMSy)
- Spent a bit of time aligning the cavity, but could only get to about 0.8
- Made some gain changes on the Y Arm PDH medm, and then more cavity tweaking for a few minutes.
- Eventually got there after careful tweaks and returning to the BS
- Checked the beatnote.

At this point, we were good with green arm alignment!

H1 General - Comment to Locking Notes - Monday 9th March - IMC now locks

corey.gray@ligo.org — Mon, 09 Mar 2026 18:01:48 -0700

Author: corey.gray@ligo.org

Report ID: 89443

After the IMC was locked, Sheila mentioned for tonight there was not alot which could be done (the next steps would be phasing for sensors out on the In-Air Tables, and after that we could move on to locking DRMI). But wanted to look at the BS & PR3 alignment. Before doing that, we did a quick alignment of the Green Arms (to make sure the ITMs were aligned).

While looking at AS_AIR camera the spot was on the camera but off to the right. So, SR2 was moved (mostly in yaw) to get the spot halfway centered on the camera (actually we had two spots here); the BS was used to then get the two spots (one from each arm) on top of each other and centered on the camera. At this point, Sheila mentioned the beatnote looked ok. Sheila also trended PR3 and said its alignment looked good too.

For the night, the rotation stage is will stay at 2W and the IMC is locked. We don't want the PSL to go over 2W, until protections for JAC are in place (trigger PD install on the In-Air JAC/IOT1 table?). And for H1 recovery tomorrow, work will continue for moving on to DRMI locking and beyond.

H1 General - Locking Notes - Monday 9th March - IMC now locks

camilla.compton@ligo.org — Mon, 09 Mar 2026 16:57:49 -0700

Author: camilla.compton@ligo.org

Report ID: 89438

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.

ISC

Images attached to this report

Non-image files attached to this report

imc_olg_09-03-2026_145625.pdf

LHO General - Mon EVE Ops Transition

corey.gray@ligo.org — Mon, 09 Mar 2026 16:28:11 -0700

Author: corey.gray@ligo.org

Report ID: 89441

TITLE: 03/09 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 22mph Gusts, 12mph 3min avg
Primary useism: 0.04 μm/s
Secondary useism: 0.31 μm/s
QUICK SUMMARY:

After a loose cable was secured, IMC work continues by Sheila/Camilla/RyanS. (BHD & Cheta work in labs). Just had a M6.0 EQ off the cloast Naples, Italy!

H1 General - OPS Monday Day Shift Summary

ryan.crouch@ligo.org — Mon, 09 Mar 2026 16:05:22 -0700

Author: ryan.crouch@ligo.org

Report ID: 89428

TITLE: 03/09 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: Corey
SHIFT SUMMARY: The MC1, and IMC/MC2 issues were solved (DAC component swap, and loose cables respectively).
LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
14:56	FAC	Kim	LVEA	N	Tech clean	15:30
15:00	FAC	Nellie	EndY	N	Tech clean	15:52
15:41	VAC	Jordan	LVEA	N	Aux cart HAM1, YB manifold	15:49
15:45	SEI	Jeff	Optics lab	LOCAL	SPI, laser hazard	18:31
16:09	FAC	Randy	LVEA	N	Biergarten work	17:12
16:29	EE	Marc, Fil	CER	N	Look at MC1 coil drivers	16:38
16:47	EE	Marc, Erik, Rahul	CER	N	DAC swap	17:07
17:35	BHD	Oli, Camilla	Optics lab	LOCAL	BHD optics work	18:33
17:51	EPO	Thomas, Sophie, Jennie	LVEA	N	Tour	18:10
17:56	BHD	Camilla	LVEA	N	Grab dog clamps	18:01
18:04	ISC	Mitch	LVEA	N	West bay parts	18:17
18:09	EE	Sheila, Marc	LVEA	N	Check racks by PSL for MC1 offset	18:21
18:25	FAC	Contractor	MidY	N	Brick unloading	21:30
19:26	ISC	Jennie, RyanS	LVEA/ HAM1	LOCAL	JAC table work	21:34
19:33	OPS	LVEA is Bifurcated Hazard	HAM1	LOCAL	LVEA Bifurcated Lazar Hazard	22:00
19:59	SUS	RyanC	CR	N	MC1 TF functions	20:50
20:04	TCS	Sophie	Prep lab	N	Cheeta work	22:30
20:44	SEI	Jeff	Optics lab	LOCAL	SPI work	Ongoing
20:44	EE	Marc, Oli	CER	N	Check on SUS rack C1	21:00
21:03	EE	Marc	CER	N	Checking on loose cables, missing screws	21:39
21:09	ISC	Sheila	LVEA	LOCAL	Talk with JAC people	21:19
21:28	VAC	Jordan, Travis	LVEA	N	Decouple aux carts by HAM1/2	22:05
21:40	EE	Marc	MidY	N	Look for jac screws	22:03
21:42	ISC	Sheila	LVEA	N	Unlock PLS rotation stage	21:47
22:02	SEI	Jim	LVEA	N	Unlock HAM2 HEPI	22:14
22:37	BHD	Oli	Optics lab	LOCAL	BHD work	Ongoing
23:05	TCS	Sophie, Thomas	Prep lab	N	Cheeta work	Ongoing

16:40 UTC HAM1/2 SUS to safe for a DAC card swap
17:10 UTC Model restart
In the MC1 investigation we ended up swapping 3 things, the DAC 0 card IO chassis, its' ribbon cable and interface card alog89427. This fixed the MC1 transfer function issue alog89435.
21:00 UTC Marc and Oli then found some loose cables for MC2/3 after Daniel did some testing on MC2's drive alog89434 alog89436
21:45 UTC Sheila unlocked the rotation stage and I turned up the power from 1W to 2Ws.
22:00 UTC Jim went out to unlock HAM2 HEPI

LHO VE - Comment to HAM1 +Y door installed

jordan.vanosky@ligo.org — Mon, 09 Mar 2026 16:01:56 -0700

Author: jordan.vanosky@ligo.org

Report ID: 89440

I isolated the HAM1 aux cart (HAM2 was isolated on Friday) from the annulus this morning. The IP current only rose to ~4.7mA before turning around showing it could hold the annulus pressure.

HAM1/2 annulus aux carts were shut down and decoupled this afternoon. The SS500 cart remains at HAM1 and will continue to pump until the pressure is low enough to valve in the HAM1 ion pump.

Images attached to this report

H1 IOO - Aligned WFS after model change

jennifer.wright@ligo.org — Mon, 09 Mar 2026 15:42:05 -0700

Author: jennifer.wright@ligo.org

Report ID: 89437

Jennie W, Ryan S

Ryan and I went to the JAC table to align the beam to the wavefront sensors after Daniel corrected (#alog 89413) the ADC channel assignment(#alog 89397) for the WFS DC readouts in the h1ascimc model last Friday.

After some alignment with the WFS A picomotor mirror we realised that the X and Y channels were swapped with pitch corresponding to channel X and yaw corresponding to channel Y.

This happens upstream of the table as the cabling seems correct from the table hookup to the pico.

WFS B is the correct way round.

Both WFS have cross-coupling between pitch and yaw but we were eventually albe to get them aligned just by moving the WFS.

This means the WFS DC channels are hooked to the correct ADC channels in the ascimc model now.

We still need to profile the beam on the table to check the placement of the WFS relative to the beam waist.

We will come back to this tomorrow.

After this we did some lateral movements of the trigger PD to centre it in the beam horizontally but had to stand down because of locking efforts.

The signal cable is not hookled up yet so we can start commissioning this and the shutter once we ge the go ahead from the IFO locking team.

ISC

Images attached to this report

H1 CDS - MC2 M3 can actually actuate again

oli.patane@ligo.org — Mon, 09 Mar 2026 14:24:53 -0700

Author: oli.patane@ligo.org

Report ID: 89436

Daniel, Marc, Sheila, RyanC, Camila, Jeff, Oli

MC2 M3 wasn't actuating (89434) and we traced it back to its DAC cable in SUS-C2 U28 card slot #5. The cable was halfway coming off. This is because there were no jack screws to screw the cables into, so over time gravity had been pulling the heavy cable out. We took a couple extra jack screws from an unused port and used them to secure the plug in place. Once we did this, we were able to actuate with MC2 M3 again and we just locked the IMC.

There are many other cables in the CER that aren't properly screwed into their ports. We pressed them in but we will need to add jack screws to them before we have something like this happen again!

FRS ticket: 37180

ISC, SUS

H1 SUS - MC1 transfer functions

ryan.crouch@ligo.org — Mon, 09 Mar 2026 14:08:24 -0700

Author: ryan.crouch@ligo.org

Report ID: 89435

I ran another set of TFs today for MC1 after the swaps relating to its' DAC in alog89427, they are looking healthy now! The state of the chamber was the same as on Friday, HEPI locked and ISI in Isolated. The SUS was also undamped with alignment offsets off.

/ligo/svncommon/SusSVN/sus/trunk/HSTS/H1/MC1/SAGM1/Data:

2026-03-09_2000_H1SUSMC1_M1_WhiteNoise_L_0p02to50Hz.xml
2026-03-09_2000_H1SUSMC1_M1_WhiteNoise_P_0p02to50Hz.xml
2026-03-09_2000_H1SUSMC1_M1_WhiteNoise_R_0p02to50Hz.xml
2026-03-09_2000_H1SUSMC1_M1_WhiteNoise_T_0p02to50Hz.xml
2026-03-09_2000_H1SUSMC1_M1_WhiteNoise_V_0p02to50Hz.xml
2026-03-09_2000_H1SUSMC1_M1_WhiteNoise_Y_0p02to50Hz.xml

See alog89400 to see the full transfer functions before the coil driver swap, and the Pitch TF after swapping the coil driver (alog89411 for the coil driver swap).

FRS 37167

Images attached to this report

H1 SUS - MC2 M2 actuation compared to PRM: better now

sheila.dwyer@ligo.org — Mon, 09 Mar 2026 14:05:57 -0700

Author: sheila.dwyer@ligo.org

Report ID: 89434

Daniel became suspicous that MC2 M3/M3 may not be actuating. I drove a 0.1Hz line on M1 on MC2, and see it clearly in the M3 L witness (osems).

When driving MC2 M2 with almost the full DAC range (300,000 counts on the test L filter bank), I see no response on M3 witness osems. Repeating this test on PRM the M3 osems see about a 10 um amplitude motion, so it seems that this level of drive should be visible if the suspension was moving.

Edited to add: Marc and Oli found some loose cables, now the actuator on MC2 M2 works.

CDS, SUS

Images attached to this report

H1 CDS - Comment to h1sush12 LIGO-DAC replacement.

erik.vonreis@ligo.org — Mon, 09 Mar 2026 13:23:51 -0700

Author: erik.vonreis@ligo.org

Report ID: 89433

Old Serial numbers

DAC: S2500460

Interface card: S2500449

New serial numbers:

DAC: S2500445

Interface card: 34924

H1 CDS - Comment to h1sush12 LIGO-DAC replacement.

ryan.short@ligo.org — Mon, 09 Mar 2026 10:57:05 -0700

Author: ryan.short@ligo.org

Report ID: 89431

JM1 and JM3 moved after this restart because of some old values in SDF for their alignment sliders, so once things were brought back up, Sheila and I realigned the suspensions and I accepted their alignment offsets in SDF. Screenshot attached.

Images attached to this report

H1 PSL - PSL 10-Day Trends

ryan.short@ligo.org — Mon, 09 Mar 2026 10:54:13 -0700

Author: ryan.short@ligo.org

Report ID: 89430

FAMIS 31128

The PMC HV supply was swapped 6 days ago (alog89349) which took the PMC down briefly. Afterwords, we did some slight PMC alignment and bumped up the pump current for PS4 to get slightly better PMC transmission. The PSL models were restarted on Friday due to timing errors (alog89413), which also briefly took things down, but everything came back without issue.

Images attached to this report

LHO VE - Mon CP1 Fill

david.barker@ligo.org — Mon, 09 Mar 2026 10:33:58 -0700

Author: david.barker@ligo.org

Report ID: 89429

Mon Mar 09 10:16:12 2026 INFO: Fill completed in 16min 9secs

Images attached to this report

H1 CDS - h1sush12 LIGO-DAC replacement.

david.barker@ligo.org — Mon, 09 Mar 2026 10:19:18 -0700

Author: david.barker@ligo.org

Report ID: 89427

WP13077 Replace suspect first LIGO-DAC in h1sush12

Sheila, Marc, Erik, Dave:

We replaced the first LIGO-DAC in h1sush12's IO Chassis. Its ribbon cable and interface card were also replaced.

Replacement parts were removed from the DTS x7eetest1 system.

No DAQ restart was required.

H1 SUS - MC1 further investigation

ryan.crouch@ligo.org — Mon, 09 Mar 2026 09:54:43 -0700

Author: ryan.crouch@ligo.org

Report ID: 89426

Taking a look at some of the MC1 signals from over the weekend with Sheila and Jeff, we've decided to next swap the DAC card, card 0 on h1susmc1. The OSEMs are moving but not seeing a request in the MASTER_OUT. T3 noisemon seems to see it first.

Images attached to this report

H1 General - Comment to OPS Monday Day Shift Start

ryan.crouch@ligo.org — Mon, 09 Mar 2026 07:43:19 -0700

Author: ryan.crouch@ligo.org

Report ID: 89425

Taking a look at the voltmons for T2/T3 of M1 and LL/UR of M2 and M3 I saw there was still some jumping seen in T2 and T3 over the weekend.

Images attached to this report

H1 General - OPS Monday Day Shift Start

ryan.crouch@ligo.org — Mon, 09 Mar 2026 07:31:20 -0700

Author: ryan.crouch@ligo.org

Report ID: 89424

TITLE: 03/09 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, 1mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.26 μm/s
QUICK SUMMARY:

IMC recovery will continue today, there will probably be some more investigation into MC1
Hopefully we'll get to further locking to check the BS.
HAM1 continues to pump down