aLIGO LHO Logbook

H1 ISC - BS alignment is as good as we can get (at this point with available resources)

keita.kawabe@ligo.org — Thu, 25 Jun 2026 14:57:32 -0700

Author: keita.kawabe@ligo.org

Report ID: 90759

After in-chamber crews physically moved the BS, I was able to restore both the IMC flashes and the sqz beam reflected by ITMX as well as ITMY in AS as well as ISCT1 REFL camera by just using the BS sliders. sqzbeam_as_isct1.png and the video PXL_20260625_204834048TS.mp4

show the sqz beam in the AS (left) and ISCT1 (right) camera when IMC was misaligned, while PXL_20260625_204905669TS~2.mp4 is the video of the IMC flashes when SQZ beam diverter was closed.

BS top suspension offsets were H1:SUS-BS_M1_OPTICALIGN_P_OFFSET = 107.00 and H1:SUS-BS_M1_OPTICALIGN_Y_OFFSET = 441.00.

Right now F2 coil is using ~10% of the DAC range (~13.3 million counts out of 135 million), F2 ~ 6%, and others are small. See BS_DAC_range.png. I don't think further trying to relieve this will be fruitful or useful.

Camilla found that ZM4 and ZM5 had additional rotation because of unintentional ASC output while in-chamber adjustments were being made. When they cleared the asc outputs the beam spot of ITMY reflection on the AS camera didn't change so the impact sshould be small.
The BS alignment looks as good as we can get with available resources at this point. Even though we know that the BS alignment nor the input alignment from PR3 to BS is perfect and that SQZ beam and the IFO beam are not co-aligned with each other, those things should be dealt with after pumping down.

sliders.png is the screen shot of most alignment sliders as of now.

INS, IOO, ISC

Images attached to this report

Non-image files attached to this report

PXL_20260625_204834048TS.mp4

PXL_20260625_204905669TS~2.mp4

H1 AOS - BBSS Pointing alignment work between yesterday and today

betsy.weaver@ligo.org — Thu, 25 Jun 2026 14:34:21 -0700

Author: betsy.weaver@ligo.org

Report ID: 90760

Following on from alog 90738, we last had the corner alignment with the BBSS at PIT +115 and YAW -1557. We decided to offload this YAW to the HEPI so the team embarked on that yesterday, likely another alog from IAS/SEI on that move later. Today we went and looked at the corner beam pointing with Keita refining the BBSS alignment to PIT +107, YAW +441 (see his alog coming).

So now, Jim and Mitchell are embarking on Actuator attachment at the piers. We will relook at the BBSS cage position with the FARO shortly after they are complete, and then re-peek at the corner alignment likely early next week.

Meanwhile, the BBSS PIT to YAW cross coupling investigaton continues...

H1 SUS - BBSS Satamp to Coil Driver Checks

oli.patane@ligo.org — Thu, 25 Jun 2026 12:27:58 -0700

Author: oli.patane@ligo.org

Report ID: 90758

Jeff, Arnaud, Betsy, Oli

Yesterday we checked the coil response for the BBSS QOSEMs. We did this at the BBSS M1 QOSEM satamp. Everything is looking good and as we expected.

We did this by putting the BBSS in SAFE, then unplugging the db15's that go to the coil drivers. In their place Jeff plugged in a fancy breakout board that separated out each of the 4 channel pins. The resistance of each of the reading device channels is listed below:

Coil Voltage (Satamp to Coil Driver)
Resistance of reading device (no uncertainty to 0.1 Ohm)		Used to measure
Resistance of reading device (no uncertainty to 0.1 Ohm)		Used to measure
Breakout (B/O) Channel 1	24.3 Ohm	CH1 (F1), CH5 (LF)
Breakout (B/O) Channel 2	20.9 Ohm	CH2 (F2), CH6 (RT)
Breakout (B/O) Channel 3	23.1 Ohm	CH3 (F3)
Breakout (B/O) Channel 4	23.4 Ohm	CH4 (SD)

With this channel breakout board we then went channel by channel to measure voltage. We turned the master switch ON so counts can head out from the COILOUTF filter bank. For each channel, we noted the COILOUTF filter bank gain sign, and if there was any voltage read out when no offsets were put in. Then we put an OFFSET in the COILOUTF filter bank and noted the voltage that we were reading. We did this for multiple OFFSETs for each channel. After testing each channel, with an offset still on, we would check the other channels to see if anyone else was seeing anything more than their default reading with no offsets, which they never saw anything different from that. Here is that data:

Cable	SUS_BS_85								SUS_BS_87
Channel	CH1		CH2		CH3		CH4		CH5		CH6
OSEM	F1		F2		F3		SD		LF		RT
COILOUTF gain	-1		-1		1		1		-1		1
	COILOUTF OFFSET	Voltage (V) (+/- 0.5 mV)	COILOUTF OFFSET	Voltage (V) (+/- 0.5 mV)	COILOUTF OFFSET	Voltage (V) (+/- 0.5 mV)	COILOUTF OFFSET	Voltage (V) (+/- 0.5 mV)	COILOUTF OFFSET	Voltage (V) (+/- 0.5 mV)	COILOUTF OFFSET	Voltage (V) (+/- 0.5 mV)
	20,000	-2.825	20,000	-2.837V	20,000	2.848	20,000	2.839	20,000	-2.826	20,000	2.836
	10,000	-1.413	10,000	-1.419	10,000	1.424	10,000	1.419	10,000	-1.413	10,000	1.418
	0	0	0	-1.00E-03	0	0	0	0	0	-1.00E-03	0	0
	-10,000	1.412	-10,000	1.416	-10,000	-1.424	-10,000	-1.42	-10,000	1.412	-10,000	-1.418
	-20,000	2.825	-20,000	2.83	-20,000	-2.849	-20,000	-2.839	-20,000	2.825	-20,000	-2.837
	With OFFSET of -20,000 (in V):		With OFFSET of -20,000 (in V):		With OFFSET of -20,000 (in V):		With OFFSET of -20,000 (in V):		With OFFSET of -20,000 (in V):		With OFFSET of -20,000 (in V):
	CH1 (B/O Ch1)	--	CH1 (B/O Ch1)	0	CH1 (B/O Ch1)	0	CH1 (B/O Ch1)	0	CH5 (B/O Ch1)	--	CH5 (B/O Ch1)	-1.00E-03
	CH2 (B/O Ch2)	-1.00E-03	CH2 (B/O Ch2)	--	CH2 (B/O Ch2)	-1.00E-03	CH2 (B/O Ch2)	-1.00E-03	CH6 (B/O Ch2)	0	CH6 (B/O Ch2)	--
	CH3 (B/O Ch3)	0	CH3 (B/O Ch3)	0	CH3 (B/O Ch3)	--	CH3 (B/O Ch3)	0
	CH4 (B/O Ch4)	0	CH4 (B/O Ch4)	0	CH4 (B/O Ch4)	0	CH4 (B/O Ch4)	--

You can see that the voltage signs are all consistant with the sign of the OFFSET * COILOUTF gain, and the values are all pretty consistant as well.

After we were done reading out the voltages for SUS_BS_85, we put offsets of -20,000 in F1, F2, and F3 and checked the voltages on all three channels. All three channels read the same voltage as they had when we had tested them individually at -20,000 counts. That table is below.

OFFSET of -20,000 for F1, F2, F3 (in V)
CH1 (F1)	2.825 V
CH2 (F2)	2.831 V
CH3 (F3)	-2.849 V

H1 TCS - TCS Chiller Water Level Top-Off (Bi-Weekly, FAMIS #64383)

corey.gray@ligo.org — Thu, 25 Jun 2026 10:33:55 -0700

Author: corey.gray@ligo.org

Report ID: 90757

Addressed TCS Chillers (Thurs [Jun25] 934-945am local time) & CLOSED FAMIS #64383.

(Still not getting FAMIS notifications and not clear which FAMIS Schedule LHO is supposed to use due to duplicate schedules being generated with the new LIGO Lab FAMIS transition.)

For measurements below, measuring from "top" of the red floaty ball.

TCSx Chiller: Had level of 28.6 cm. Added 525mL for 30.5cm.
- Odd Note: levels about the same as last fill, but this one took double the water fill.
TCSy Chiller: Had level of 10.2 cm. Added 100mL for 10.6cm.
There was no water in the small cup under the slow leak.

TCS

H1 SUS - LHO BBSS Top Mass Added Mass Configuration

ibrahim.abouelfettouh@ligo.org — Thu, 25 Jun 2026 10:11:47 -0700

Author: ibrahim.abouelfettouh@ligo.org

Report ID: 90756

Recorded our added mass configuration on the Top Mass. See diagram and associated pictures.

Top Side: 100g total, both on Front (by convention, so the side opposite the OSEM flags)

Bottom Side: 200g total, 100g on Front, 100g on Back

Total Added: 300g

See the diagram.

SUS

Images attached to this report

H1 SUS - QOSEM SatAmp to QOSEM Cable Resistance

oli.patane@ligo.org — Thu, 25 Jun 2026 09:59:24 -0700

Author: oli.patane@ligo.org

Report ID: 90747

Jeff, Betsy, Arnaud, Oli

Yesterday afternoon we went to the BBSS QOSEM satamp and checked the coil resistance. We did this by putting the BBSS in SAFE and then unplugging the Satamp to Duopus cables one by one. Each of these three cables have the pins for two QOSEMs, split as CH1 + CH2, CH3 + CH4, and CH5 + CH6. Each cable was unplugged and then the pins for each coil probed. Below are the results. These values are all pretty similar.

Coil Resistance (Satamp to Duopus)
	CH1-2 (SUS_BS_81)		CH3-4 (SUS_BS_82)		CH5-6 (SUS_BS_83)
Channel	CH1	CH2	CH3	CH4	CH5	CH6
CH Coil Pins	23 -> 10	18 -> 5	23 -> 10	18 -> 5	23 -> 10	18 -> 5
OSEM Mapping	F1	F2	F3	SD	LF	RT
Coil Resistance	39.1 +/- 0.1 Ohm	40.0 +/- 0.2 Ohm	39.0 +/- 0.2 Ohm	39.7 +/- 0.2 Ohm	40.0 +/- 1.5 Ohm	40.5 +/- 0.5 Ohm
Notes					Larger than normal variation

LHO General - Comment to Thurs DAY Ops Transition

corey.gray@ligo.org — Thu, 25 Jun 2026 09:19:53 -0700

Author: corey.gray@ligo.org

Report ID: 90755

ALSO: Have "Red Flag" Warning from noon-9pm PDT with high winds and dry conditions.

H1 ISC - OMC dither frequency in SDF safe

sheila.dwyer@ligo.org — Thu, 25 Jun 2026 09:09:10 -0700

Author: sheila.dwyer@ligo.org

Report ID: 90754

yesterday we had difficulty locking the OMC on the sqz beam. This was because the dither frequency change in 76587 never made it into the SDF safe, although it's written in the OMC guardian. Every time we went through SDF revert it is set incorrectly, then corrected when the OMC locks. I've accepted the change in SDF safe now.

Images attached to this report

LHO General - Thurs DAY Ops Transition

corey.gray@ligo.org — Thu, 25 Jun 2026 07:36:29 -0700

Author: corey.gray@ligo.org

Report ID: 90751

TITLE: 06/25 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: MAINTENANCE
Wind: 12mph Gusts, 6mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.06 μm/s
QUICK SUMMARY:

LVEA continues to be Laser SAFE as we move to finish this round of in-chamber work. Ongoing system activities: BBSS, SQZ, CRS, SPI

Untripped EY SEI from Venezuela EQ last night (HEPI to Robust Isolated + ISI to Damped).

Also taking ETMx back to ALIGNED (it tripped due to NorCal EQ and then had the hardware watchdog trip and had been left in damped).

DetChar meeting continues (unlocked kitchen door).

H1 SEI - CRS ready for installation in chamber

arnaud.pele@ligo.org — Wed, 24 Jun 2026 18:17:37 -0700

Author: arnaud.pele@ligo.org

Report ID: 90750

Shoshana, Michael, Oli, Arnaud

Verified capacitive plate are wired correctly
Verified the HOQI wiring, and found where we had a flip between HOQI A and B (we had plugged the cables the wrong way at the db9 input of the hoqi preamp).
Shoshana made a new MEDM screen, see attached
Michael calibrated the angular HOQI readout in um in the HOQI1_DIST filterbank
Tested the picomotor in chamber, using the spare channel from SPI. The screen is accessible either from the sitemap->ISC->Picomotors->TCS Y CO2->PICO 8 (or directly from the CRS_OVERVIEW screen)
- Right Arrow = Pico arm moves Counter Clockwise (looking from the back of the Pico)
- Left Arrow = Clockwise
- 10000 steps at 500Hz = 1.25 turn
Verified overnight data, but the air turbulence from the cleanroom is still too high (and motion at 15mHz too high) to have a good baseline. The hoqi noise is hovering between 10 and 100pm/sqrt(hz)>10Hz
Created a folder under /ligo/svncommon/SeiSVN/seismic/HAM-ISI/H1/CRS to store and share CRS data, scripts and templates

CRS is ready for installation in chamber

Next:
Test that positive HOQI signal corresponds to the corner cube moving away from the sensor (same convention as OSEMs)
Calibrate the HOQI PDs to power
Install the fiber feedthrough and start cabling up in chamber

Images attached to this report

H1 SQZ - Comment to SQZ OSC Scan Progress, ASC on ZM4/5 working and Better alignment OMC scan completed.

camilla.compton@ligo.org — Wed, 24 Jun 2026 17:12:03 -0700

Author: camilla.compton@ligo.org

Report ID: 90749

We tried changing PSAMS while SQZ ASC was on, it took 30s to settle. The misalignment peak did change between scans but only a small amount. Misalignment peak was around 8.5% and then 10% of 00 peak.

We did not manage to get back to the lowest misalignment as above, even with dithering PZT2 around the 00 peak and maximizing with OMC and OM3.

LHO General - Ops Day Shift End

thomas.shaffer@ligo.org — Wed, 24 Jun 2026 16:38:53 -0700

Author: thomas.shaffer@ligo.org

Report ID: 90748

TITLE: 06/24 Day Shift: 2200-2330 UTC (1500-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
SHIFT SUMMARY: Two large earthquakes have rolled through in the last hour, a 7.1 from Venezula and a 6.9 from Japan. EY SEI has tripped, but all suspensions are still damping.

The LVEA is laser SAFE as we continue toward closing out chambers.
LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
20:18	SAF	LVEA is LASER -SAFE-	LVEA	NO	LVEA is LASER -SAFE-	12:18
22:55	SPI	SPI LASER IS ON	LVEA	Y	SPI LASER is ON	18:42
00:18	CRS	CRS laser is ON	LVEA	Y	CRS laser is ON	18:42
14:45	fac	kim	lvea	-	technical cleaning	16:45
15:06	fac	chris.tyler.eric.randy	Y1-FCT Enclosures	-	tumbleweed clearing	16:51
17:51	sei	jim	HAM3	-	CPS work	19:47
17:53	vac	gerardo	HAM3	-	viewport work	19:05
17:53	pem	robert	EX		grounding studies	17:55
17:54	fac	randy	lvea	-	WestBaycleanroom lights	21:53
18:02	faro	jason.ryanC	ham3	-	FARO set up	19:19
18:06	-	Betsy	LVEA	-	Talk to HAM3 crew	18:47
18:25	crs	michaelR	lvea	-	Turning OFF CRS laser + CRS checks	18:43
19:07	vac	gerardo.jordan	Y-BeamManifold	-	scaffold search	19:19
19:42	CE/pem	carlos.shrey	x-arm	n	seismometers placement along arm	23:15
20:12	ops	betsy	lvea	n	walkthru	20:32
20:26	detchar	jenne group	lvea	-	DetChar tour	21:19
20:29	faro	ryanC.jason	lvea	-	faro @ham3	22:47
20:43	SEI	Jim, Michael, Shoshana.mitch	LVEA	-	BSC2 weighting (all but Jim out @2222)	23:04
20:55	spi	oli.jeff.arnaud	lvea	-	susr2 check (please no BBSS work!)	23:30
21:01	vac	jordan.gerardo	lvea	-	viewport inspection @ham2	21:30
21:20	ee	fil	lvea	-	checking cables at PSL Closet+tcsy rack	21:28
22:45	VAC	Jordan, Jake, Owen	LVEA	n	Checking on CP1 RGA	ongoing
23:17	PEM	Robert and others?	EX	n	Magnetometers	ongoing?
23:30	SEI	Arnaud	LVEA	n	CRS work	ongoing

H1 SQZ - SQZ OSC Scan Progress, ASC on ZM4/5 working and Better alignment OMC scan completed.

camilla.compton@ligo.org — Wed, 24 Jun 2026 16:24:33 -0700

Author: camilla.compton@ligo.org

Report ID: 90742

Ryan S, Sheila, Eric O, Camilla, Keita. Follow on from 90698.

This morning Sheila and Eric adjusted the SQZ IFO ASC to run centering loops from AS_A and AS_B to ZM4 and ZM5, in preparation for running OMC scans with a variety of psams settings. See attached.

Starting trying to take OMC scans with the SQZ beam, with less misalignment than we saw in 90615, to eventually use Begum’s scripts to repeat with different PSAMS settings.

Had negative counts on OMC QPDs, needed to turn Stage 3 H1:ASC-OMC_B_AWHITEN_SET3 off and take H1:ASC-OMC_B_WHITEN_GAINSTEP to zero, then had expected light on H1:ASC-OMC_A/B. We moved SRM to get the beam centered on AS_C, so with the DC centering servos ran and then the OMC ASC servos ran, the beam was centered on AS A, B, C and OMC A and B.

Sheila and Ryan, went to the misalignment peak with the PZT offset and then started a dither over it and tired to change OM3 and OMC alignments but couldn't reduce the size of the beam, only make it worse. They undid the SRM alignment change, this did not help.

Sheila and Keita then tried to lock the OMC on the 00 mode, as in 80010 but it was not stable. Sheila then put a dither on the OMC PZT and we maximized the TEM00 peak with OMC and OM3 SUS, we improved the flashes 10%. OMC from (P-1900, Y -400) to (P -1300, Y -480) and OM3 from (P -1400, Y +95) to (P -1400, Y +65). The OMC scan after that was at a much better alignment, see data attached and below. Strangely this is showing worse mode mismatch than the the alignment was poor in 90615.

Shortly after this HAM5 and ZM6 WDs tripped (CPS WD trip) and afterwards, the OMC scan alignment was poor again. Sheila made some progress on getting the code to work /userapps/release/sqz/h1/scripts/HAM6_related/ham7_psams_sweep_QPD_center.py, but more work is needed.

PSAMS	Dark	TEM00	TEM02 (Mis-match)	TEM01 (Misalignment)	Mismatch* (% of TEM02)
ZM4 6.2V, ZM5 -0.4V	0.0209615	0.620414	0.0397442	0.0409605	3.04%

*calculated with TEM02 / (TEM00 + TEM02)

Images attached to this report

H1 SQZ - Comment to HAM7 - FC path mode matching projections from beam profile data

begum.kabagoz@ligo.org — Wed, 24 Jun 2026 16:03:33 -0700

Author: begum.kabagoz@ligo.org

Report ID: 90746

Code for the data points upstream of ZM2 attached. The measured beam widths and their corresponding position are listed in the script. The real raw data with the screenshots from the beam profiler UI is attached to the main log.

Non-image files attached to this report

HAM7_LHO_beammeas_upstream_ZM2.py

LHO General - Wed DAY Ops Summary

corey.gray@ligo.org — Wed, 24 Jun 2026 15:09:08 -0700

Author: corey.gray@ligo.org

Report ID: 90733

TITLE: 06/24 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:

Started out the day with a large "local" earthquake (this caused a Hardware Watchdog trip--see Dave's alog).

Went laser SAFE to switch to different work for the BBSS (and allowed for a DetChar tour and other activity without the need for laser goggles).
LOG:

1430-1539 technical cleaning @lvea (kim)
- 1540-1556 H2 PSL technical cleaning (kim)
- 1557 FCES technical cleaning (kim)
- 1656-1738 EX technical cleaning (kim)
1504-1645 Tumbleweed clearing of the Y1-FCT "canyon" while it's cooler (chris, tyler, randy, eric)
1514 Had a fairly large earthquake pass thru which mainly affected EX systems. Didn't catch EX ISI quick enough to bypass it and prevent SUS SW watchdogs. Since the HW WD tripped, Fil will need to make a trip out to EX to power things back up.
- Jim later noticed that the SUS (etmx + tmsx) were both looking very noisy and they were ringing up. To stop this, Master Switch was turned OFF for both etmx & tmsx and this eventually calmed them both down.
1558 SQZ injector beam into HAM6 (sheila)
1600 Restarting ETMx Hardware Watchdog at EX (fil)
1603-1607 restarting dustmonitor HAM2 (ryanC)
1614-1705 Pump Cart set up at HAM2 (jordan, owen, jacob)
1621 oplev & viewport for HAM3 (gerardo)
1642-1745 EX ground study (robert)
1644 CPS work at HAM3 (jim)
- 1720-1915 mitch joining
1655 testing SEI guardian (tj)
1725 -1800 Checking lights for west bay cleanroom (randy)
1730-1743 Tour group from in Control Room (amber)
1800-1920 FARO set up at HAM3 (jason.ryanC)
1806 Chatting to HAM3 crew (betsy & jeff)
1824 Turning off CRS laser & crs work (michaelR)
1905-1919 Looking at scaffolding along Y-BeamManifold for GV6 (gerardo.jordan)
1940 seismometer placement on X-arm (carlos, shrey)
2008-2031 lvea walkthru (betsy)
2026-2119 DetChar tour @lvea (jenne)
2028 FARO afternoon work (ryanC.jason)
2042 BSC2 ISI weight adjustments (michael.jim,shoshonna,mitch)
2050 TCS y-rack near ham3 + psl closet (fil)
2054 susr2 rack checks (jeff.oli.arnaud)
2100-2133 viewport inspection @ham2 (jordan.gerardo)
2210 Handing off the shift to TJ

H1 INS - Dark offset for OMC DCPD

keita.kawabe@ligo.org — Wed, 24 Jun 2026 14:56:30 -0700

Author: keita.kawabe@ligo.org

Report ID: 90745

Adjusted the dark offset of OMC DCPDs in A0 and B0 filters and zero-ed A and B offsets (and disabled them).

	H1:OMC-DCPD_A0_OFFSET	A_OFFSET	B0_OFFSET	B_OFFSET
Old	-158	68e-6	-134	-803e-6
New	-81.6	0	-89.5	0

I don't know exactly why people split these offsets in two different places, maybe that's because dark offset scripts was written when 512k ADC didn't exist?

Let's use A0 and B0 offsets for ADC rather than putting ridiculously small numbers in A and B.

H1 SQZ - Comment to HAM7 - FC path mode matching projections from beam profile data

begum.kabagoz@ligo.org — Wed, 24 Jun 2026 14:06:22 -0700

Author: begum.kabagoz@ligo.org

Report ID: 90744

The beam width data kindly tabulated by Camilla, the R(V) data from Camille's dcc E2100298, and the analysis code .py are attached, in the .zip. Fair warning, the analysis code also makes a bunch of plots I find useful to look at but another user may find irritating :)

Non-image files attached to this report

code_data_LHO90613.zip

H1 SUS - BBSS M1 QOSEM Drive Transfer Function

thomas.roocke@ligo.org — Wed, 24 Jun 2026 13:15:57 -0700

Author: thomas.roocke@ligo.org

Report ID: 90743

To aid in testing the BBSS M1 QOSEM coils for issues related to the cross coupling (see LHO alog 90665), below is the DC tranfer function from DAC counts (16 bit) to the voltage across the QOSEM coils. This assumes a coil resisatnce of 35ohms, which is the nominal spec, but they can vary by ~10%.

DAC drive to voltage across the coil = 3.18e-5 V/cts

H1 SUS - BBSS TF comparison: Teststand BOSEMs vs QOSEMs vs Chamber QOSEMs

oli.patane@ligo.org — Wed, 24 Jun 2026 12:35:55 -0700

Author: oli.patane@ligo.org

Report ID: 90741

I've made plots comparing three sets of transfer functions.

2026/05/26: On the LVEA Teststand with BOSEMs (90356) (individual results)
2026/06/01: On the LVEA Teststand with QOSEMs (90440) (individual results)
2026/06/10: In Chamber with QOSEMs (90590) (individual results)

Here are the comparison plots between the three. The most important plots right now are the P2Y and Y2P plots. They can be found in /ligo/svncommon/SusSVN/sus/trunk/BBSS/Common/Results/allbbss_2026_teststand_vs_chamber_BOSEMs_vs_QOSEMs/ and have been committed as r13043.

Side note: Since Arnaud and I realized our calibration DAC compensation mistake yesterday (90720), I have reanalyzed the last few measurements, including the three being compared here, using /ligo/svncommon/SusSVN/sus/trunk/BBSS/Common/MatlabTools/plotBBSS_dtttfs_M1.m. These are three measurements that had been taken with the 28bit DAC compensation gain in the COILOUTF filter set to gain(4096) = gain(2^12), which is the correct compensation when accounting for the difference in DAC counts between a 28bit and 16bit DAC. This compensation means that the calibration factor in plotBBSS_dtttfs_M1.m should've just accounted for the 16-bit DAC (since the rest was already accounted for), but it had been set to 18-bit DAC, so I reran them. The measurements that had been reanalyzed were 2026-05-26_1700, 2026-06-01_1700, and 2026-06-10_1700, committed as r13041.

Note: All three of these measurements were taken before the sign swap was implemented in the COILOUTF filter banks.

Non-image files attached to this report

2026-05-26_1700_H1SUSBS_M1_ALL_TFs.pdf

2026-06-01_1700_H1SUSBS_M1_ALL_TFs.pdf

2026-06-10_1700_H1SUSBS_M1_ALL_TFs.pdf

allbbsss_2026_teststand_vs_chamber_BOSEMs_vs_QOSEMs_ALL_TFs.pdf

allbbsss_2026_teststand_vs_chamber_BOSEMs_vs_QOSEMs_ALL_ZOOMED_TFs.pdf

H1 SUS - BBSS top mass drive calibration

arnaud.pele@ligo.org — Wed, 24 Jun 2026 12:11:53 -0700

Author: arnaud.pele@ligo.org

Report ID: 90739

Following up from 90723 we (roughly) calculated the BS top mass drive (cts) to bottom mass motion (urad) measured by the oplev. This will allow to (re)calibrate the top mass sliders in physical units. The screenshot attached show the ndscope used for this calculation. The data was taken before the sign convention was corrected (90725), so the signs were flipped from the ndscope in the table below:

+0.15 [P_urad/P_cts]	+0.35 [Y_urad/P_cts]
+0.1 [P_urad/Y_cts]	+1.65 [Y_urad/Y_cts]

The slider calibrations to implement (at next opportunity) in the gain of the slider filterbanks are :

P calibration = 1/0.15 = 6.6 [P_cts/P_urad]
Y calibration = 1/0.35 = 0.6 [Y_cts/Y_urad]

Images attached to this report

H1 ISC - Comment to ITMX taken back to DRMI top mass OSEMs, BS Alignment adjusted to compensate

arnaud.pele@ligo.org — Wed, 24 Jun 2026 12:00:27 -0700

Author: arnaud.pele@ligo.org

Report ID: 90740

Given this calibration the newest BS offsets (P +115, Y -1557) [cts] corresponds to the calibrated offsets (P +17.25, Y -2569) [urad at M3] when only considering the P2P and Y2Y calibration. When taking into account the cross coupling those offsets are (P -138, Y -2529) [urad at M3].

This defines the amount of yaw motion (and direction) to offload this offset with HEPI : Rotate HEPI ~2.5mrad clockwise

H1 ISC - ITMX taken back to DRMI top mass OSEMs, BS Alignment adjusted to compensate

camilla.compton@ligo.org — Wed, 24 Jun 2026 11:23:18 -0700

Author: camilla.compton@ligo.org

Report ID: 90738

Follow on from 90719. Jennie, Keita, Betsy, Sheila, Camilla, Ryan S, Oli, Arnaud

Before doing any more mechanical BS offloading, we decide to put ITMX back too it's March DRMI top mass osems values, as described in alog90708, we expected we'd need to move ITMY to compensate for this, but did not.

Used the SQZ beam. Mis-aligned ITMY. Moved ITMX towards correct Pit value. Compensated with BS Pitch and Yaw to keep beam on AS AIR. Moved PR3 to keep beam on ISCT1 REFL camera. We did not fine tune fringing. Keita opened PSL light pipe an further tuned PR3 to get PSL beams both on cameras. Ending sliders here. Ndscope of the fringing on AS_A/B here.

BS pitch is now close enough we will do no further mechanical pitch offloading now, it will be Yaw offloaded SEI system. Arnaud checked the oplevs to known that for the -1500 counts of BS yaw slider, this is ~ 2.5mrad.

Both ITMX and ITMY are now at their March DRMI top mass osems locations (11:02 PDT 19 March 2026).

	Starting today	After ITMX moved back to DRMI M0 OSEMs
ITMX	P -280, Y +94	P -96, Y +104
BS	P +520, Y -1677	P +115, Y -1557
PR3	P -247, Y -245	P -195, -242

Images attached to this report

H1 CDS - WP 13208 cdswiki OS upgraded

jonathan.hanks@ligo.org — Wed, 24 Jun 2026 10:49:28 -0700

Author: jonathan.hanks@ligo.org

Report ID: 90737

As per WP 13208 the cdswiki was down yesterday for an OS upgrade.

H1 CDS - Earthquake has tripped ETMX Hardware Watchdog

david.barker@ligo.org — Wed, 24 Jun 2026 08:39:10 -0700

Author: david.barker@ligo.org

Report ID: 90734

Corey, Dave:

An EQ quickly tripped the ETMX SEI SWWD. I bypassed the SWWD and tried to drive the ISI to prevent the HWWD from tripping, but to no avail. HWWD tripped 08:36 and will need manual reset when the EQ has passed.

LHO General - Wed DAY Ops Transition

corey.gray@ligo.org — Wed, 24 Jun 2026 07:42:21 -0700

Author: corey.gray@ligo.org

Report ID: 90732

TITLE: 06/24 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: MAINTENANCE
Wind: 5mph Gusts, 2mph 3min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.07 μm/s
QUICK SUMMARY:

BBSS, SPI, CRS, and baffling work continue, with planning for possible laser safe time for BBSS actuator work.

H1 CDS - More 20bit-DAC testing on H1 production front ends

david.barker@ligo.org — Wed, 24 Jun 2026 07:12:54 -0700

Author: david.barker@ligo.org

Report ID: 90731

Erik, Jonathan, EJ, Dave:

On Monday 21jun2026 we did some more investigation of the General Standards 20bit-DACs in h1iscex and h1susb2h34.

h1iscex:

Following my successful loop-back testing of this 20bit-DAC to the PEM ADC, EJ confirmed that this 20bit-DAC passed the Monday tests. This card is still a bit of mystery as to why it is working with a MPS=256B. It is a unique 20bit-DAC, older than all the others (it is 2015, all the others 2019 or later). It has a 4th region (Region1) on the lspci -vv scan missing in the other DACs.

h1susb2h34:

Monday's testing showed that both of the 20bit-DACs on this frontend are non-operational. The first because it shares an Adnaco with the Timing-Card, the second because it shares an Adnaco with the LIGO-DACs. In both cases the LIGO card is forcing MPS=256B which causes the 20bit-DACs to drive no output voltage (constant FIFO=empty).

My original SUSAUX testing was faulty, I was looking at the stop stages of PR2, SR2 but the 20bit-DAC drives M2,M3 for these suspensions. I was able to verify that these lower stages have not been driven since the January 2026 upgrade.

h1sush12:

As an aside, I took a look at the MPS for h1sush12. This has no 20bit-DACs, it is all LIGO-DAC. This is a W3323 computer, the additional cores were needed for the large number of models. Strangely this machine is running with MPS=128B on all cards, even though it could run at 256B, presumably resulting is a loss of DAC performance. We will investigate this on the test stand's W3323.

H1 SUS - Comment to BS Pitch Pointing Offloaded

timothy.ohanlon@ligo.org — Wed, 24 Jun 2026 07:11:32 -0700

Author: timothy.ohanlon@ligo.org

Report ID: 90730

LLO also saw a drop in power output on the BS oplev. The current sum is around 12 percent of what the sum was before the vent which matches the drop in LHO BS oplev power.

H1 SUS - Comment to BS Sign Convention fixed throughout signal path

arnaud.pele@ligo.org — Wed, 24 Jun 2026 00:43:51 -0700

Author: arnaud.pele@ligo.org

Report ID: 90728

Following this sign change, we verified the following conventions for the M1 actuation :

Positive offset on the coil ouptut filterbanks corresponds to positive qosem signal on M1(figure 1)
Positive offset on the cartesian basis (test filterbanks) corresponds to positive cartesian signal on M1 (figure 3)

Figure 2 and Figure 4 show the dc cross couplings for the local and cartesian basis drive, as as reference for the on-going xcoupling investigation.

The two scripts to make those plots were saved in the svn under /opt/rtcds/userapps/trunk/sus/h1/scripts

push_pull_bs.py
push_pull_bs_cartesian.py

Images attached to this report

H1 SUS - QOSEM Readout Sign Convention Checks

thomas.roocke@ligo.org — Wed, 24 Jun 2026 00:22:50 -0700

Author: thomas.roocke@ligo.org

Report ID: 90729

To verify that the QOSEM readout has the expected sign convention, as detailed in D2500284, I injected a longtidual offset into the BBSS M1, via the QOSEM coils, and monitored M1, M2, M3 OSEMs. The QOSEM readout sign should be consistent with the BOSEMs and AOSEMs.

Figure 1 plots M1 F1_x, M2 LL, M3 UR and the test L injection into M1. Due to the location of these OSEMs they should all readout with the same sign. Here we see that the sign is consistent between the QOSEM, BOSEM and AOSEM for this given longitudal offset, verifying that the QOSEM sign convention is indeed as documented.

Images attached to this report

H1 SEI - Comment to CRS Chamber Side Testing Continues

michael.ross@ligo.org — Tue, 23 Jun 2026 18:34:41 -0700

Author: michael.ross@ligo.org

Report ID: 90727

We took a quick spectrum to check the HoQI performance. The CRS is very rung up so this noise floor is not indicative of the final performance. Yet the noise floor already looks good.

Images attached to this report

H1 SEI - CRS Chamber Side Testing Continues

shoshana.apple@ligo.org — Tue, 23 Jun 2026 18:25:50 -0700

Author: shoshana.apple@ligo.org

Report ID: 90715

[Arnaud, Michael, Jim, Fil, Shoshana]

As mentioned in 90702, one of the readouts for the CRS HoQI amplifier wasn't working, after investigating we figured out that it was an issue with a broken op-amp in a transimpedance amplifier (HoQI B, channel E/COS). Fil switched out the op-amp so we now have a working chassis. Our best guess is that the op-amp failed after plugging it into the rack.

The HoQI on the left side of the CRS (SN01-005, currently HoQI2) had much lower fringe visibility than the other one (SN02-007) since yesterday. We figured out that the laser collimator was positioned in a way where the beam wasn't hitting the center of the photodiodes. The laser collimator was re-aligned and we were able to greatly increase the fringe visibility so the HoQIs now match.

HoQI 1 (SN02-007), SIN: 86.7%, COS: 79.4%, MCOS: 84.9%

HoQI 2 (SN01-005), SIN: 81.4%, COS: 82.7%, MCOS: 80.1%

CRS was balanced, currently has a estimated resonance frequency of 15.7mHz, but we will re-check it in the morning. We are leaving the laser on over night hoping to get some noise measurements, both due to the air currents in the clean room, and the fact that we didn't ground the damping capacitors, it looks unlikely that it will damp down overnight.

Arnaud got the ellipse fitting working, the python script is in /opt/rtcds/userapps/trunk/isi/h1/scripts/write_ellipse_values3.py

We added a gain 0.0847 um/cnt (1064 nm/4pi) to the HoQI Dist filter banks to calibrate the HoQIs into distance. We also changed the CRSRY_PHI_SUM matrix elements to 2.75 to put the RY channels into urad.

An unrelated mystery: HoQI1 and HoQI2 are switched, we aren't sure where in the chain they get flipped, but right now we are guessing it's at one of the cables to the chassis

SEI

H1 SUS - BS Sign Convention fixed throughout signal path

oli.patane@ligo.org — Tue, 23 Jun 2026 18:12:25 -0700

Author: oli.patane@ligo.org

Report ID: 90725

Previously (90441), Tom, Ibrahim, and I had found out that the QOSEM coil drivers were wired opposite as compared to other OSEMs. To compensate for this at the time (since we were attempting to use damping), we had swapped the signs of the damping gains. But we had only swapped those gains, meaning that other actuation coming through the TEST or OPTICALIGN filter banks was still pushing the coil drivers the opposite way from expected. Today we finally decided to fix it to reduce confusion wrt the direction the BS was moving when offsets were put in (offsets were moving the BS in the opposite direction than expected).

To do this all I did was put the M1 DAMP filter gains back (before, after) to being negative and then swapped the signs of the gains in M1 COILOUTF (before, after). To put the beamsplitter back with the OPTICALIGN offsets that it had before, I then swapped the sign of each offset.

I will update the SUS Sign Conventions document to mention that the QOSEMs require the opposite COILOUTF signs from nominal.

So now EVERY BBSS OPTICALIGN slider offset from before 2026/06/24 00:50 UTC requires the opposite sign to be recreated.

Images attached to this report

H1 AOS - Comment to BS Alignment with SQZ Beam, got MICH fringes with SQZ and IFO beam

keita.kawabe@ligo.org — Tue, 23 Jun 2026 17:57:05 -0700

Author: keita.kawabe@ligo.org

Report ID: 90724

Since IMTX was moved today, I had to move PR3 to compensate in order to regain IMC flashes in the AS camera as well as ISCT1 camera.

H1:SUS-PR3_M1_OPTICALIGN_P_OFFSET is now -247.0 (used to be -140).

H1:SUS-PR3_M1_OPTICALIGN_Y_OFFSET is now -245.0 (used to be -583).

H1 SUS - Comment to BS Pitch Pointing Offloaded

ryan.short@ligo.org — Tue, 23 Jun 2026 17:46:48 -0700

Author: ryan.short@ligo.org

Report ID: 90723

Keita's note: After Jason recentered BS oplev, we changed the BS sliders to see the sign of the sliders (we knew that they were flipped) and how bad the pit to yaw coupling was.

Sign of the H1:SUS-BS_M1_OPTICALIGN_P_OFFSET and H1:SUS-BS_M1_OPTICALIGN_P_OFFSET are systematically wrong.

Positive PIT (right column top) in the slider consistently makes negative PIT on oplev, M2 OSEM and M1 OSEM, i.e. positive PIT tilts the BS up when positive offset is added to the pit slider.

Same story for YAW, negative PIT (left column top) in the slider consistently makes positive YAW for all sensors available, i.e. positive YAW rotates the BS clockwise when viewed from the top.

Arnaud and the gang will fix the sign issue.

PIT to YAW coupling is about 2 YAW per 1 PIT (i.e. PIT actuation make BS move more in YAW). YAW to PIT is not bad.

Positive PIT of 50 counts (uncalibrated) made negative 10urad in PIT and negative 20urad in YAW according to oplev. This agrees with our experience of observing how the beam spot moved in chamber as well as on the AS and ICST1 cameras when trying to move BS in PIT using the slider.

Interestingly, P2Y coupling seems to be OK for M1 (1:0.17 if we trust the QOSEMs), bad (about 1:0.7) for M2 and absolutely terrible (1:2) for M3 oplev.

Negative YAW of 20 counts made positive YAW of about 30urad and almost unmeasurable amount of PIT according to oplev.

Images attached to this report

H1 CDS - new trace color system for ndscope

erik.vonreis@ligo.org — Tue, 23 Jun 2026 17:27:38 -0700

Author: erik.vonreis@ligo.org

Report ID: 90722

Ndscope has a new system for picking trace colors that tries to maintain a high contrast between the trace and the background.

You can test the new system by running "ndscope-test" instead of ndscope on any workstation, laptop, or login portal. Give it a try and let me know what you think.

H1 SUS - BBSS Model M1 to M3 TFs and DC values

oli.patane@ligo.org — Tue, 23 Jun 2026 17:24:01 -0700

Author: oli.patane@ligo.org

Report ID: 90720

Arnaud, Oli

As part of our BBSS alignment and investigation, I used /ligo/svncommon/SusSVN/sus/trunk/BBSScomparetripleparams.m to look at the DC values of our current model when actuating at M1 and reading out at M3.

I made a few edits to comparetripleparams.m in order to allow me to do this easily, and I've committed those changes as r13039.

The plots (P, Y) show that the DC value for M1 P to M3 P is 0.029 rad/Nm and M1 Y to M3 Y is 0.129 rad/Nm. These plots can be found in /ligo/svncommon/SusSVN/sus/trunk/BBSS/Common/Results/comparetripleparams/comparetripleparams/2026-06-23_M1toM3Model/triplemodelcomp_2026-06-23_M1toM3Model_M1toM3.pdf r13040.

We then converted into cts/N using (1e-6)*(1/DACdrive)*(1/coilDriver)*(1/forceCoeff).

For this we used DACDrive = 20/2^16 cts/V, forceCoefficient = 1.694 N/A, and coilDriverTransconductance = 0.011919 A/V. The reason why DACDrive = 20/2^16 cts/V and not 20/2^28 is because we already compensate for the difference between a 16-bit DAC and a 28-bit DAC in the COILOUTF filter bank so we don't need to put that into our calibration.

This gives us:

Calibration factor [cts/N] = (1e-6)*(1/(20/2^16[cts/V]))*(1/0.011919 [A/V])*(1/1.694 [N/A])

= 1.623e5 [cts/N]

Then multiplying this calibration factor by our earlier fractional values for P and Y gives us:

Pitch slider calibration : 4.7e-3 cts[M1]/urad[M3]

Yaw slider calibration: 20.9e-3 cts [M1]/urad[M3]

Images attached to this report

H1 SUS - Comment to BS Pitch Pointing Offloaded

jason.oberling@ligo.org — Tue, 23 Jun 2026 17:21:02 -0700

Author: jason.oberling@ligo.org

Report ID: 90721

The BBS OpLev has been recentered. I had to yaw the beam onto the QPD, as it was not on it. Once recentered, the SUM counts were around 2400, which is much lower than for the old BS, which was up around 20k. I checked the Output Configuration Switch on the BBS OpLev chassis in the biergarten and it has not changed, the amount of gain is still 0 dB. The other explanations are the coating on the BBS (OpLev beam is at 635 nm, which is not a design wavelength for the coating, so the %R at 635 nm for the BBS could be very different than the old BS) and a failing OpLev laser. I'll check the power output from the laser to see how it's doing (likely tomorrow).

H1 SUS - BS Pitch Pointing Offloaded

ryan.short@ligo.org — Tue, 23 Jun 2026 17:14:47 -0700

Author: ryan.short@ligo.org

Report ID: 90719

B. Weaver, C. Compton, R. Short

Carrying on from alog90708 posted at lunch, Betsy, Camilla, and I offloaded the BS pitch sliders mechanically at the suspension. This was a tad tricky since we were looking at the beam(s) at HAM3 in front of PR2, so we had to work out blocking 1 ITM beam in order to not be confused by both beams crossing each other after the long PR chain of optics. In the end, we worked out the process to bring the BS PIT slider from +1000 to 0 which meant pitching the BS optic HR "up" (PUM roll bar "in"). Unblocking the other ITM, we got both beams overlapping onto each other with a little more slider to see how much better we could get them and see flashes in the AS_AIR camera (PIT = -300, YAW +1560).

Once back in the control room, Keita scanned BS alignment to find the SQZ beam reflected by ITMX as well as ITMY in AS camera as well as ISCT1 camera, ending with BS PIT = -520, YAW = 1677. With this alignment, IMC flashes reflected by ITMX as well as ITMY were visible in both of the cameras. Though SQZ beam and IMC flashes are not coaligned, the corner alignment is already pretty good as of now.

At this point we want to:

1) Recenter the OPLEV

2) Go in and physically calibrate which way the sliders go as seen on the oplev and at the HAM3 PR Beams since there is confusion around the sliders (direction, calibration, cross coupling)

3) Based on 2) Potentially make a request for HEPI YAW correction tomorrow when they resume HEPI "fine" alignment and actuator reattachment (TBD convo with SEI/IAS)

4) Get on with landing HEPI/actuator attachment, etc.

5) Final round of BS PIT SUS mechanical Offloading

ISC

H1 General - OPS Tuesday Day shift summary

ryan.crouch@ligo.org — Tue, 23 Jun 2026 16:33:02 -0700

Author: ryan.crouch@ligo.org

Report ID: 90710

TITLE: 06/23 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: SPI in-chamber installation was finished yesterday, CRS work, and alignment work continued ending with Jason recentering the BBS OPLEV as of 23:30 UTC.
LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
20:18	SAF	LVEA IS LASER HAZARD	LVEA	YES	LVEA IS LASER HAZARD	12:18
14:30	FAC	Kim	LVEA	Y	Tech clean	15:16
15:44	FAC	Kim	LVEA	Y	Tech clean	17:03
16:20	FAC	Randy	LVEA	Y	Moving scissor lift out of E bay	16:33
16:22	SAF	Betsy	LVEA	Y	Opening light pipe	16:24
16:44	FAC	Chris	Ends	N	End Station FAMIS checks	18:39
16:44	PEM	Robert	EndY	N	Grounding study	17:43
17:01	SEI	Jim	LVEA	Y	HAM3 CPS work	19:31
17:13	ISC	Betsy	LVEA	Y	HAM3 pictures	17:30
17:15	CDS	Dave	REMOTE	N	DAQ restart	17:30
17:47	SEI	Mitch	LVEA	Y	Join Jim	19:20
18:14	FAC	Tyler+1	LVEA	Y	Walkthrough with vendor	18:31
18:15	ISC	Camilla, Betsy	LVEA	Y	Alignment checks	18:48
18:22	PEM	Carlos, Shrey, Matilda	Site, Xarm	N	Installing seismometers, overpass	23:03
18:57	CRS	Michael, Shoshana, Corey	LVEA	Y	CRS work by HAM3	20:05
19:22	ISC	Betsy	LVEA	Y	HAM3 checks	19:25
19:37	VAC	Gerardo	LVEA	Y	Viewport (1) removal by HAM5	23:05
19:40	PEM	Robert+3	EndX	N	PEM checks, grounding study	21:40
20:06	VAC	Jordan	LVEA	Y	Join Gerardo @ HAM5	20:30
20:11	CDS	Dave	Roof	N	Looking at fire	20:21
20:12	ISC	Betsy, RyanS	LVEA	Y	HAM3 work, alignment, Betsy out 22:15	22:47
20:38	SEI	Jim	LVEA	Y	CPS work, SEI cabling around HAM3	00:11
20:59	ISC	Camilla	HAM3	Y	Join team alignment	22:43
21:01	SEI	Mitch	LVEA	Y	CRS work, HAM3	21:17
21:04	VAC	Jordan, Jake, Owen	LVEA	Y	Remove RGA from CP1	23:15
21:35	CRS	Michael, Shoshana	LVEA	Y	CRS work	Ongoing
22:44	SUS/IAS	Jason	LVEA	Y	Recenter BBS OPLEV and auto OFF/ON the FARO	Ongoing
22:55	SPI	SPI LASER IS ON	LVEA	Y	SPI LASER is ON	Ongoing
22:45	SPI	Jeff	LVEA	Y	Turn on SPI laser in @ 22:45	22:56
22:59	SEI	Mitch	LVEA	Y	Talk to Jim	23:08

A wildfire sparked up to our southwest by Benton City around 19:00 UTC, the smoke could easily be seen to the left of Rattlesnake. Multiple helicopters, and a plane were out fighting it. As of the end of shift it looks like they've mostly put it out based on the smoke or the lack of.

H1 SPI - SPI Pathfinder Analog LO Phase Rotators Set to 0.0 [deg] and 0.0 [deg]

jeffrey.kissel@ligo.org — Tue, 23 Jun 2026 16:11:30 -0700

Author: jeffrey.kissel@ligo.org

Report ID: 90718

J. Kissel, for J. Freed At the last minute on 2026-06-18, Josh figured out that we had errantly been sending the SPI's double mixer two copies of a COS wave of 4096 Hz rather than a SIN and COS (LHO:90680). This was because someone had errantly put a 90 [deg] rotation in the SIN analog output path. He fixed it before he left, but didn't save it in the SDF system and it got lost during Monday's bootfest of h1seih23 (LHO:90689). I'm not sure if Josh (or anyone) tuned it to any specific value, but I've changed the SIN analog rotation phase to 0.0 and accepted it in SDF so we don't lose it. Josh may add some more details in the comments below, in the comments to his LHO:90680.

H1 SPI - SPI Pathfinder Laser ON

jeffrey.kissel@ligo.org — Tue, 23 Jun 2026 16:07:33 -0700

Author: jeffrey.kissel@ligo.org

Report ID: 90717

J. Kissel I'm looking to get some overnight data of the SPI pathfinder so start looking at science signals and debugging. Jennie has been turning OFF the laser via the external-to-PSL Uniblitz shutter controller (see LHO:90491) over this past long weekend, and each night this week because she was worried about the stray beam from the FBR_PWRIN PD, but again -- this is 0.2 [mW] and not an issue for humans or equipment as long as the LVEA is laser hazard. She didn't know the power was so low, and followed her good instincts. But yeah, I want to get some over night data, so I've turned ON (unshuttered) the SPI laser input via the Uniblitz shutter controller box by the PSL. I'd like to leave it ON as long as the LVEA is laser hazard. If we need to go back to laser safe and I'm not around, one can easily shutter the laser by turning OFF the controller box: power it off with the rocker switch on the back, or unplugging the box from the wall, or both. With no power, the shutter defaults to CLOSED, which blocks the SPI pick-off path (only) from inside the PSL, thus making the entire SPI laser system laser safe anywhere outside the PSL.OpsInfo, SPI

H1 SUS - BBSS Makeshift Test Stand Optical Lever Gross Pointing and Range Check

ibrahim.abouelfettouh@ligo.org — Tue, 23 Jun 2026 15:08:36 -0700

Author: ibrahim.abouelfettouh@ligo.org

Report ID: 90709

Ibrahim, Oli, Thomas, Betsy

Before we flew the BBS in, we did a sanity-check experiment to compare slider values with a laser-pointer optical lever. This experiment follows Jeff's G1200698 math for an optical lever (picture also attached).

Setup:

A laser pointer was pointed at the BBS HR side such that the HR and AR reflections could be seen on a paper near the laser pointer. The initial position was recorded on a paper, and then slider values were driven to their maximum range in P and Y. The distance between the laser source and the HR surface was recorded. The experiment was done with BOSEMs and then with QOSEMs.

Method:

When the laser pointer is incident on the BBS, there are two reflected beams (AR and HR). The average distance of these was taken along with the average distance from the BBS. This was done by calculating the distance to the BBS and adding the half-thickness of 30mm. This gives us "one beam" and "one distance' to go off for P and Y. See the attachment below for an image of the paper used during the experiment. This was done once for BOSEMs and then again with QOSEMs.

A few notes:

The setup was replicated and the distance was remeasured on a different day and this is why the distances are different.
The QOSEM as-it-is is inversed in its actuator sign convention and you can see this in the attached diagram. One of our action items is to rectify this. So right now, +P = Pitching up instead of down with respect to the HR. In general, we will abide by T1200015, the SUS/Actuator Sign Convention.

Results and Analysis

Pitch is in purple and Yaw is in Orange. The equation used was obtained from "G1200698, the Oplev Infamous Factor of Two", which is essentially the same outline as our experiment, a diagram of this is attached.

This equation is: DØ= DS/2L Where,

Ø is the angle in radians (adjusted to urad below), S is the displacement in the beam spot, L is the distance from the laser source to the optic.

For these data, the total range of the Opticalign sliders was considered (from lowest negative to highest positive). Thus, a half the range would apply if the sliders were zeroed.

	BOSEM	QOSEM
Distance from HR surface (in)	130	118
Distance from HR surface (mm)	3302	2997.2
Average distance from optic	3332	3027.2
Pitch Displacement Total - +-1500 cts	5.5	5.75
Yaw Displacement Total +-4000 cts	46.75	40.75
Pitch Angle Swept (urad)	825.33	949.72
Yaw Angle Swept (urad)	7015.31	6730.64
Total Pitch Count Sweep (+-1500)	3000	3000
Total Yaw Count Sweep (+-4000)	8000	8000
Pitch urad/Ct	0.28	0.32
Yaw urad/Ct	0.88	0.84
Pitch Ct/urad	3.63	3.16
Yaw Ct/urad	1.14	1.19

Conclusion:

For a QOSEM Drive:
- Pitch at M3 read +-475urad (1/2 the total sweep of 949.72 shown above), which is equivalent to 3.16 Opticalign Cts per urad.
- Yaw at M3 read +-3365urad (1/2 the total sweep of 6730.64 shown above), which is equivalent to 1.19 Opticalign Cts per urad.
BOSEM and QOSEM ranges are comprable
No cross coupling was observed. Remember that this was done on the test stand a few weeks ago, before we found P:Y and Y:P coupling in chamber.

Next Steps:

Next, we're going to compare these results with the M3 AOSEM readouts once these are reliable. We will also compare these results with the model (which is used to corroborate slider calibration). Ultimately, this will help with the calibration of our slider values (both within the actuator slider actuation vs. sensing and from counts to real units).

Once we get a working OpLev (it's not on the BBS right now), we'll be able to get a more fine measurement of this kind.

Again, this is just a gross alignment check for information about our pointing and the capacity of our actuation.

SUS

Images attached to this report

Non-image files attached to this report

OpticalLever_FactorOfTwo_G1200698-v1.pdf

H1 SPI - 2026-06-22 SPI Pathfinder -- Installation Complete!

jeffrey.kissel@ligo.org — Tue, 23 Jun 2026 14:21:49 -0700

Author: jeffrey.kissel@ligo.org

Report ID: 90716

J. Kissel, J. Wright, T. Shaffer, J. Warner, J. Freed (belated aLOG covering 2026-06-22 activity) After enjoying a lovely long, Juneteeth Holiday weekend, TJ and I wrapped up the few loose ends that were left after the 2026-06-18 super push to get everything installed (see last update; LHO:90676). - As a fall out of LHO:90667, Jim, Arnaud and I discussed the pros and cons of using the current, D1000907-v7, balance mass "Payload & Suspended Mass Assembly" arrangement in regards to the W9 corner. We concluded that leaving the D1000907-v4 configuration for this corner in place -- i.e. having 11.6 [kg] of mass in small, modular, optional components -- was better that having one "giant" 10 [kg] mass in "the same" location (on the table top, but in the same W9 corner). As such, we left the plates as re-installed on LHO:90713, with the acknowledgement that the final configuration to create a balanced ISI may be different even further than D1000907-v7. - Using a beam profiler, we measured the Beam Profile of the beam returning from M_C1 on the HAM23 ISIJ Reflector. This is to, at least roughly, confirm the radii of curvature of the M_C1 mirror. We expected a 2 [mm] diameter beam, and we got a 2 [mm] beam diameter. A more thorough aLOG to come. - We did NOT address the stray beam that Jennie mentions in her summary -- yet. I'll also write a separate aLOG on this, but in short -- it's a ~0.2 [mW] beam that's what ~18% reflection there is off of a silicon diode, and it hits the -X/-Z rim of the chamber of the +Y door, and the (splotchy) spot size is ~4-5 [mm] in diameter. The SPI team has been aware of this beam since testing in the optics lab (see mention of it, e.g. in LHO:90455), but hoped that it would land on some part of the SPI Shroud assembly, but it *just* misses it. With this last item, we consider the Installation and Integrated Test Plan COMPLETE (T2500024) ... to as good as possible with the HAM3 ISI still locked. And that ... qualifier is a "just in case" qualifier, as it's a "we'll see what happens" when the ISI gets unlocked, and we've got an excellent amount of remote adjustability to be able to recover the MEAS IFO's alignment if HAM3 moves a lot between - "locked," - "re-balanced and damped" and - "isolated with feedback and DC positioning engaged." Essentially, we've launched the SPI pathfinder into space, and now its up to out built-in remote controlled actuators and sensors to take us home to achieve our scientific goals (see T2600019). Super congrats to all, and similarly large thank you. We did a thing!SEI, SPI, SYS

Images attached to this report

H1 SEI - Comment to ISI HAM3 Wide Wall Balance Masses vs. SPI

jeffrey.kissel@ligo.org — Tue, 23 Jun 2026 13:48:31 -0700

Author: jeffrey.kissel@ligo.org

Report ID: 90714

Masses were re-installed as of 2026-06-18! See LHO:90713.SEI, SPI

H1 SPI - Comment to SPI install update - day 6

jeffrey.kissel@ligo.org — Tue, 23 Jun 2026 13:47:43 -0700

Author: jeffrey.kissel@ligo.org

Report ID: 90713

Note mentioned in the summary of activities in the main entry -- per LHO:90667, we re-installed all the ballast or balance mass discussed during this 2026-06-18 day's session. See attached "after" picture.

Images attached to this report

H1 CDS - Comment to DAQ restart for new PWRCS Beckhoff Chiller channels

david.barker@ligo.org — Tue, 23 Jun 2026 13:44:50 -0700

Author: david.barker@ligo.org

Report ID: 90712

Here is a random new channel which has non-zero data trended back one month to view its data back when it had its original name.

Images attached to this report

H1 CDS - DAQ restart for new PWRCS Beckhoff Chiller channels

david.barker@ligo.org — Tue, 23 Jun 2026 13:40:24 -0700

Author: david.barker@ligo.org

Report ID: 90711

WP13303 Reimage PWRCS Beckhoff, update Corner HEPI Pump controller INI

Patrick, Erik, Jonathan, Dave:

Patrick created a new H0EPICS_PWRCS INI file. All of the EPICS channel names have changed since the first version of this system, and 40 of the new channels have old-channel equivalents. To preserve recent minute trends, the data acquired so far were transferred to the new names as part of the upgrade.

The sequence followed was:

- Remove the old names from the edc_green_ioc IOC. 43 disconnects at this point (40 from H0EPICS_PWRCS and 3 from H1EPICS_HEPIPUMPL0)

- Create the copy scripts to be ran on TW0,TW1 to copy the old files to the new, so that the new channels will "continue from where we left off"

- Create the new H1EDC.ini and verify its changes.

- Stop daqd on TW0 and TW1

- Run the copy scripts on TW0 and TW1

- Restart the 0-leg, followed quickly by restart of the EDC.

- Wait till 0-leg was fully operational, including TW0

- Restart the 1-leg

All went well except for the usual GDS1 needed a second restart, FW1 restarted itself after 5 minutes.

H1 AOS - BS Alignment with SQZ Beam, got MICH fringes with SQZ and IFO beam

camilla.compton@ligo.org — Tue, 23 Jun 2026 12:50:39 -0700

Author: camilla.compton@ligo.org

Report ID: 90708

Continued from 90691. Betsy, Keita, Sheila, Oli, Eric, Camilla, Ryan S, Jenne

First thing, we went back to alignment we had ITMX SQZ the "flashes" and "fly-bys" yesterday, put the same size oscillation on the BS, but saw no flashes of fly bys. Betsy took a video of what the two SQZ beams looked like at PR2 at this alignment, they were crossing each other.

We then rethought the alignments from yesterday, we are leaving:

ITMX and ITMY at March DRMI top mass OSEM sensors
ZM4 and ZM5 to get SQZ beam on SQZT7 irises
ZM6 to O4 sliders.
SR3 at the Oplev/slider positions of March DRMI/O4 (all similar)
SR2 Yaw slider back to O4, Pitch to get SQZ ITMY beam on AS_AIR (+440urad PIT sliders different from O4).
SRM aligned to improve SRY fringes (+200urad PIT sliders, +400urad YAW sliders different from O4).

Once we did this, we had SRY fringes, Betsy and I then adjusted the BS to bring the beams back on top of each other at PR2. This was a change in the BS sliders from (P 1000, Y 1290) to (P 1350, Y 1180).

Keita then wobbled ITMX and found the SQZ beam off ITMX! Aligned ITMX to get MICH flashes at AS_AIR, AS_A/B and ISCT1 REFL. He had to move ITMX from (P -96, Y 104) to (P -280, Y 94).

He then got the PSL IX and IY reflection in the AS_AIR camera in this alignment. Sliders at this alignment attached.

However as we are not sure we trust the ITMY alignment form top mass osems (from 90551), we want this Pitch change to be in ITMY, so ITMX is at it's known DRMI pointing. We could try to walk these, maybe along with SRC which might reduce some of our Pitch differences in SR2 and SRM. This change is so small that we will go ahead with mechanically offloading BS Pitch. The BS YAW will not mechanically changed.

The OMs are also not currently in their O4 sliders/osems position, attached. We could verify the SQZ beam pointing by putting these back if we thought that was needed.

Images attached to this report

H1 CDS - Workstations updated

erik.vonreis@ligo.org — Tue, 23 Jun 2026 09:58:30 -0700

Author: erik.vonreis@ligo.org

Report ID: 90707

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

H1 SEI - Comment to ETMY BRS not damping down

shoshana.apple@ligo.org — Tue, 23 Jun 2026 09:55:27 -0700

Author: shoshana.apple@ligo.org

Report ID: 90706

Michael is in this week and fixed the EMTY BRS by raising the upper threshold (H1:ISI-GND_BRS_ETMY_HIGHTHRESHOLD) from 4000-->8000 for 20 minutes, see 90693

Current Thresholds:

H1:ISI-GND_BRS_ETMY_HIGHTHRESHOLD: 4000

H1:ISI-GND_BRS_ETMY_LOWTHRESHOLD: 2000

Looking through ndscope it the same changes were made to the ETMX BRS, raising the thresholds

H1 SEI - Comment to CRS Chamberside testing started

michael.ross@ligo.org — Tue, 23 Jun 2026 09:45:06 -0700

Author: michael.ross@ligo.org

Report ID: 90705

Adding numbers for the fringe contrasts for each PD:

HoQI 1 (right):

Sin: 85%

Cos: 80%

MCos: 84%

HoQI 2 (left):

Sin: 70%

Cos: 5% (electronics issue)

MCos: 71%

H1 General - OPS Tuesday Day shift start

ryan.crouch@ligo.org — Tue, 23 Jun 2026 07:31:10 -0700

Author: ryan.crouch@ligo.org

Report ID: 90704

TITLE: 06/23 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: MAINTENANCE
Wind: 3mph Gusts, 1mph 3min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.08 μm/s
QUICK SUMMARY:

Continuation of CRS, and aligment today
DetChar FF in the MPR, try to use the kitchen door

H1 SEI - ITMs as-built balance mass pictures

arnaud.pele@ligo.org — Mon, 22 Jun 2026 19:35:24 -0700

Author: arnaud.pele@ligo.org

Report ID: 90703

Pictures of as-built balance mass of ITMs taken today to compare with drawings in anticipation of rebalancing both ITMs with the added baffle weight

ITMY:

table: pic1, pic2, pic3
corner 1 side wall: pic4
corner 2 side wall: pic5
corner 3 side wall: pic6 and pic7

ITMX:

table: pic8, pic9, pic10
corner 1 side wall: pic11
corner 2 side wall: pic12, pic13
corner 3 side wall: pic14, pic15

Images attached to this report

H1 SEI - CRS Chamberside testing started

arnaud.pele@ligo.org — Mon, 22 Jun 2026 19:05:04 -0700

Author: arnaud.pele@ligo.org

Report ID: 90702

Shohana, Michael, Fil, Jim, Arnaud

wp 13344

Following up from 90652. The CRS chamber side testing started:

The CRS electronics (HOQI amplfier, Laser Driver and TEC controller) and laser were installed in the TCS-R2 rack, where the permanent cables are installed (see pic1)
The E-stop was mounted on the TCS-R2 rack with label 'CRS local E STOP' (see pic1)
The db25 in the CER was plugged to the HAM AA chassis going to ADC
db25 and fiber patch cables were ran on the floor from the rack to the 'CRS' cleanroom (see pic2)
The laser was turned on to verify HOQI signals and HOQI alignment. The 2nd channel on HOQI B from the TIA is saturating (it was working last week) so we pulled the board out and will inspect in the EE shop tomorrow. In terms of algnment we are getting >70% fringe visibility and will continue to tune it tomorrow.

Images attached to this report

H1 SUS - BBSS M2 BOSEMs Centered, M3 AOSEMs cabled and centered

ibrahim.abouelfettouh@ligo.org — Mon, 22 Jun 2026 19:02:17 -0700

Author: ibrahim.abouelfettouh@ligo.org

Report ID: 90701

Ibrahim, Oli

Today, Oli and I installed and centered the M2 BOSEMs and centered and attached the cables for the M3 AOSEMs. AOSEM and BOSEM cams were also inspected and centered.

A few notes:

One of the M3 lower cables was not taut enough (LL) so after centering it was removed and stowed securely. We'll think more on how to fix this to the structure safely from the optic. LLO attached theirs around the LS figure 8 so we will likely do the same. See a picture.
M3 OSEM values haven't been normalized via the OLG adjustment so they "look" uncentered but they are centered. This will be applied tomorrow so they should look even on the spedometers.
As a side-quest, we were also checking for rubbing (for the 3rd time) to see if there's a reason behind P:Y (and Y:P) coupling in OSEM slider readouts - alog 90697. We found no evidence of rubbing or touching, which is frustrating. We will return to it tomorrow.

Next:

We are now able to take BRD measurements in-chamber so we'll do that tomorrow. Hopefully, the P:Y coupling issue is resolved. We'll see.
Re-attach lower M3 cable (LL) and fix them to their final resting place.
Take TFs.

SUS

Images attached to this report

H1 SUS - BBSS Pitch Yaw Coupling Investigation - Coil Driver Chain

thomas.roocke@ligo.org — Mon, 22 Jun 2026 18:19:28 -0700

Author: thomas.roocke@ligo.org

Report ID: 90697

[Tom, Ibrahim, Oli]

Summary: The yaw / pitch coupling seen on the BBSS is not due to the the coil driver chain.

As noted in LHO alog 90665, we are seeing strong pitch yaw coupling on the BBS, when actuating via the top stage QOSEM coils. When we try and adjust the optic yaw we see a 1:5 response in pitch and vice versa. This is seen in both the QOSEM readouts, and visually using an IR beamcard on the PSL beam bouncing off the optic.

To investigate whether the cause was electronic in nature, we went into chamber to ensure that only the F2 and F3 QOSEM coils are being driven when requesting yaw drive. We used a multimeter to measure the voltage drop across the coils, to determine whether theyre being driven or not. As we expected, only the F2 and F3 coils are being driven, with equal and opposite magnitude, when trying to drive yaw. This suggests that this coupling is not coming from the coil electronics chain, or an issue in CDS.

H1 IOO - Aligned JAC wavefront sensors

jennifer.wright@ligo.org — Mon, 22 Jun 2026 17:54:33 -0700

Author: jennifer.wright@ligo.org

Report ID: 90700

I took an opportunity while the BSC team was in the control room and opened the light pipe and aligned the WFS on IOT1 while JAC was unlocked.

This was done at 200mW.

I used the manual adjustment knobs on the picomotor mounts as the IOT1 table is not hooked up to its pciomotor controller currently.

Got both WFS A and B as close as I could using this method. NB: pitch and yaw on QPD A are swapped as the manual pitch adjuster changes the yaw degree of freedom. I need to check this in the physical wiring for the QPDs.

Images attached to this report

H1 SPI - Comment to SPI install update - day 6

jennifer.wright@ligo.org — Mon, 22 Jun 2026 17:46:56 -0700

Author: jennifer.wright@ligo.org

Report ID: 90699

Just did an 8 hour trend of the fiber power monitor channels for REF and MEAS channels (left two plots) and the optical lever QPDs (right two plots) to check whether we expect variations on the order of ~2V on the QPDslike we saw on Thursday before and after baffle installation.

From this trend the power appears to drift more than this for two hours after unshuttering the laser (around 15:56 UTC), but once it reaches a steady state both QPDs were only drifting by 1V and the fiber power input monitor PDs by 1V or less.

Conclusion: I think we would have seen a dramatic power drop on Thursday when we installed the shroud, that I would expeact to have been much larger than the trends I saw today.

Images attached to this report

H1 SQZ - SQZT7 Beam profiles/alignment, no progress made.

camilla.compton@ligo.org — Mon, 22 Jun 2026 17:02:59 -0700

Author: camilla.compton@ligo.org

Report ID: 90698

Eric, Ryan S, Camilla

Went onto SQZT7 and checked on the M^2 profiler. It needed their alignment procedure ran but as we're aren't at a set alignment we did not do this yet.

In the control room we used the ASC set up in 88777 and had to adjust the H1:SQZ-ASC_TRIGGER_THRESH_ON/OFF, it worked well when we changed PSAMS but we then realized we needed a ZM4/5 ASC rather than a ZM5/6 ASC for SQZT7 profiles. Tried just changing the output matrix, did not work.

Strangely, when I used the SQZ IFO ASC screen's "!graceful clear history", we now have outputs in the LOCK OUTPUTs but the beam looks a lot clearer on AS_AIR camera. We are now in a different alignment than we have been, but it's better on AS_AIR so we'll reassess tomorrow...

H1 General - OPS Monday Day shift summary

ryan.crouch@ligo.org — Mon, 22 Jun 2026 16:32:37 -0700

Author: ryan.crouch@ligo.org

Report ID: 90695

TITLE: 06/22 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: CRS, SPI at HAM3, BS / input alignment work, and a little bit of beam profiling at HAM7 continued today.
LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
20:18	SAF	LVEA IS LASER HAZARD	LVEA	YES	LVEA IS LASER HAZARD	12:18
14:41	FAC	Kim	LVEA	Y	Tech Clean	15:50
15:34	VAC	Jordan	LVEA	Y	CP1 checks	15:43
15:53	SPI	Jennie	LVEA	Y	Unshutter SPI laser	15:56
16:10	FAC	Kim	LVEA	Y	Tech clean	17:01
16:22	SUS	Jennie	LVEA	Y	Open light pipe, IOT1 work, light pipe closed at 1700	17:00
16:40	SEI	Jim, Arnaud	LVEA	Y	BSC2 cabling, 1 person in-chamber	18:29
17:00	SPI	Shoshana	LVEA	Y	H2 enclosure to HAM3 parts shuffle	18:09
17:06	PEM	Robert	EndX	N	Grounding study	18:20
17:13	SUS	Ibrahim, Betsy	LVEA	Y	BS pitch adjustment in-chamber, by HAM3 checks, Betsy out 1830	18:49
17:24	SUS	Oli, Camila	LVEA	Y	Help alignment team by HAM3	18:46
17:33	OPS	RyanS	LVEA	Y	Bring Dust monitor to BSC2 crew	17:50
17:57	VAC	Gerardo	LVEA	Y	Inspect viewports, input/output tube	18:20
18:00	ISC	Keita	LVEA	Y	Talk to HAM3 crew	18:42
19:02	SUS	Oli	LVEA	Y	Move a chassis	19:10
19:48	PEM	Carlos, Shrey	Site	Y	Huddle test at vertex	20:54
19:49	PEM	Robert	Site	N	Searching for a seismometer	20:54
20:00	CDS	Patrick	Ends	N	Check on Beckhoff computers	20:22
20:13	SPI	Jeff, Jim	Optics lab, LVEA	Y	SPI work, optics lab then HAM3 at 21 UTC, Jim in at 2100, Jeff out at 2259	23:22
20:33	PSL	Betsy	LVEA	Y	Shutter PSL laser	20:40
20:35	VAC	Jordan, Gerardo	LVEA	Y	CP1 RGA scans and checks	22:55
20:40	SPI	Jennie	LVEA	Y	Search for a laptop	20:53
20:55	PEM	Robert, Carlos, Shrey	EndY	N	Retrieve seismometer	22:49
20:59	SPI	TJ	LVEA	Y	Join Jeff at HAM3 for SPI work	22:05
21:00	ISC	Betsy	LVEA	Y	Progress checks	21:26
21:05	SUS	Oli, Fil	LVEA	Y	Plug in chassis for BS	21:28
21:22	CRS	Shoshana, Michael	LVEA	Y	CRS work by HAM3	Ongoing
22:04	SQZ	Camilla, Eric, RyanS+1	LVEA	Y	Beam profiling at HAM7, RyanS out at 23:10	23:15
22:05	CRS	Arnaud	LVEA	Y	Join CRS team	Ongoing
22:09	SUS	Oli, Ibrahim	LVEA	Y	BS work	Ongoing
22:14	SEI	RyanC	Ends	N	Reset VFD panels for HEPIs, EY then EX	23:04
22:28	SAF	CRS	LVEA	YES	CRS laser ON near HAM3	Ongoing
23:32	IAS	Jason	LVEA	Y	FARO auto OFF/ON	23:37
23:34	ISC	Betsy, Robert	LVEA	Y	Checks	Ongoing

21:43 UTC Small power glitch
- HEPI ETMX, ETMY WD tripped. The pump stations went down as well, they came back with no issues.
- ISI ETMX ST1, ST2 WS tripped

H1 SEI - BS CPS replugged

arnaud.pele@ligo.org — Mon, 22 Jun 2026 14:45:07 -0700

Author: arnaud.pele@ligo.org

Report ID: 90696

Jim, Arnaud

The x12 in-vac BSC2 / BS ISI CPS sensors were replugged to their feedthrough as per D1003079. Jim worked from the platform, verifying the signals were live with a cds laptop while I was plugging them in from the chamber. Before starting this work we turned on the interface chassis and had to power cycle corner 3 a couple of times before getting the -18V LED from the back panel to turn on.

Images attached to this report

H1 ISC - Comment to BS alignment, could see SQZ beam off ITMX fly-bys at AS Port

camilla.compton@ligo.org — Mon, 22 Jun 2026 14:15:20 -0700

Author: camilla.compton@ligo.org

Report ID: 90694

Ryan S and I went back to the ITMX and BS alignment of the best ITMX SQZ beam "fly-bys", we did not see them or any flashes again.

H1 AOS - BRS Thresholds Changed

michael.ross@ligo.org — Mon, 22 Jun 2026 14:04:41 -0700

Author: michael.ross@ligo.org

Report ID: 90693

I increased both BRS damping threshold defaults to stop the ringing behavior that we've seen after Beckhoff restarts. The defaults are hard coded into the BRS Beckhoff control under the follow lines:

H1_ISI_GND_BRS_ETMY_LOWTHRESHOLD: INT:=2000;(*~ (OPC : 1 : visible for OPC-Server) (OPC_PROP[0005] :3: read/write) (OPC_PROP[0101] :Lower Damping Threshold: DESC)*) H1_ISI_GND_BRS_ETMY_HIGHTHRESHOLD: INT:=4000;(*~ (OPC : 1 : visible for OPC-Server) (OPC_PROP[0005] :3: read/write) (OPC_PROP[0101] :Upper Damping Threshold: DESC)*)

I changed the LowThreshold from 800 to 2000 and the HighThreshold from 2000 to 4000.

H1 ISC - Comment to BS alignment, could see SQZ beam off ITMX fly-bys at AS Port

keita.kawabe@ligo.org — Mon, 22 Jun 2026 13:44:35 -0700

Author: keita.kawabe@ligo.org

Report ID: 90692

Found the ITMX alignment that sends IMC flashs all the way to AS camera AND the SQZ beam all the way to ISCT1

But, as of now, IMC flashes don't come back to ISCT1 at all, and SQZ beam only comes back to AS camera via ITMY reflection. PRM is misalilgned.

The ITMX alignment is very different from where I started but this is expected as we have moved PR3 by a large amount when we tried to center the IMC flashes on ITMX.

sqz -> SR chain -> BS-> ITMX -> BS -> PR-chain -> ISCT1

	before/after
H1:SUS-ITMX_M0_OPTICALIGN_P_OFFSET	-96/-125
H1:SUS-ITMX_M0_OPTICALIGN_Y_OFFSET	104/-331

In the attached video (PXL_20260622_203143545TS~2.mp4), ITMY is misaligned and only ITMX reflection reaches two cameras. In the ISCT1 REFL camera you can see a big bright beam which is from SQZ, while in the AS camera you can see IMC flashes.

What we should do is to refine ITMX alignment such that we can see ITMX reflection of IMC flashes in ISCT1. After that, if the IMC flashes arestill visible in AS camera, scan BS alignment to find ITMY reflection of IMC flashes in ISCT1. If the flashes are not visible in AS camera, we need to do some math.

Images attached to this report

Non-image files attached to this report

PXL_20260622_203143545TS~2.mp4

H1 ISC - BS alignment, could see SQZ beam off ITMX fly-bys at AS Port

camilla.compton@ligo.org — Mon, 22 Jun 2026 12:38:05 -0700

Author: camilla.compton@ligo.org

Report ID: 90691

Betsy, Ibrahim, Oli, Keita, Camilla. Follow from 90665 where we left ITMY and SR2 in a strange location.

Summary: With ITMs back to top mass osems and BS at (P 1000, Y 1290), we have seen fly-by of SQZ beam of ITMX at AS port. Expect BS is moving to much to get steady beam. SR2 alignment very different than March/O4 (+500urad P, +150urad Y).

9am. We started by putting ITMs, SRM, SR2, SR3 back to March DRMI time sliders (11:02 PDT 19 March 2026), attached sliders. We did not like that ITM PIT top mass osem sensors were far from the March time (-30urad for ITMX, +220urad ITMY).

We tried adding -170 to the ITMY Pitch slider as per 90551, this still took us very far form the osem sensors.

9:33am We took ITMs, SRM, SR2, SR3 back back to the sensors (top mass osems) in March DRMI time (11:02 PDT 19 March 2026), attached sliders of this.

We then misaligned SRM but did not get our SQZ beam back on AS_A,B or AS_AIR camera off ITMY. We then went back to the time Thursday we had the beam on the camera at the current ITMY pitch pointing, moved according to osems for SR2 and oplev for SR3 (as HAM5 moved Thursday late afternoon 90671). Got the SQZ beam from ITMY back on the camera as per last Thursday, but this time we are happy with out ITM pointing.

We started the /ligo/home/sheila.dwyer/SUS/BS/BS_raster.xml but still could not see sign of SQZ beam off ITMX. BS was at (P 1000, Y 1000)

10:15am Went into HAM4 and moved BS sliders to get SQZ beams on top of each other: (P 1000, Y 1290). This is encouraging that even with a different ITMY position, the BS pointing is very similar to last week. Sliders attached.

On AS_A and AS_B we could see intermittent flashes of the SQZ beam off ITMX as it hit the sensors, we could also see it "fly-by" on the AS_AIR camera. We moved BS in a few 100's of counts and ITMX in ~100urad counts to try to improve this, it was intermittent (more flashes when there was more activity in the changer and when BS was not damped) but we did not improve it. Our best fly-bys are attached, typical good flashes also attached, amplitude of flashes as are expected. We'd later like to go back to this alignment.

We tried using SR2 to center ITMY SQZ beam on AS_AIR camera but the beam quality got worse we we reverted. Expect there’s a better SRC alignment could find, currently SR2 slider is ~ 500urad different than March!

Images attached to this report

H1 SPI - Comment to SPI install update - day 6

thomas.shaffer@ligo.org — Mon, 22 Jun 2026 10:08:18 -0700

Author: thomas.shaffer@ligo.org

Report ID: 90690

More details regarding the baffle installation:

When placing the below table baffle brackets, there was a ballast mass baffle (D1700262) that was blocking the angle bracket for the furthest -Y bracket. The bracket could not slide under the ballast mass baffle (bmb), so we decided to move the bmb in the +Y direction a few inches and I had to loosen the baffle panel within the feet to slide it up a few mm and then reclamp. This allowed the bracket to slide under the baffle just to the side of the feet, but the move partially exposed a corner of the shiny ballast mass stack.

The lower baffle shroud that covers the breadboard needed the fiber spools to be moved. We moved them over one set of bolt holes, but they are quite close to chamber edge, I'd guess around 1/2". Jeff then centered the two aperatures to the SPI beam, and we called it good. We still need to B&K the whole area.

Images attached to this report

H1 CDS - h1crsproc model running on h1seih23

david.barker@ligo.org — Mon, 22 Jun 2026 10:00:01 -0700

Author: david.barker@ligo.org

Report ID: 90689

WP13318 h1crsproc model install

Shoshana, Arnaud, Jim, Jonathan, Erik, EJ, Ryan C, Dave:

We installed the first version of the h1crsproc model on h1seih23 at 09:27 Mon22jun2026PDT. Because this took one of the two spare cores on this W2245 machine, this required a reboot to force the exception to this rule. We will upgrade this machine to a W3323 before the RGC/IPC upgrade.

A DAQ+EDC restart was needed, no major issues were found.

H1 SEI - CRS Transport to Chamber Side and Other Updates

shoshana.apple@ligo.org — Mon, 22 Jun 2026 09:54:22 -0700

Author: shoshana.apple@ligo.org

Report ID: 90652

[Shoshana]

Craned the CRS over to the temporary clean room over by HAM3 on 6/18. Unfortunately the flexures (SN13,SN20) broke during the transport process. It seemed like a clean break that was potentially caused by the proof mass jolting upwards crushing the flexures (photos attached), and the locks remained in place.

CRS was re-suspended chamber side HAM3 with flexures SN15/SN19, which is the last of the approved flexures of the first batch, but the other batch is ready for pickup. Suspension was painless as the locks kept the proof mass centered even after the break. The CRS CoM was balanced by eye.

There isn't an easily accessible outlet near the temporary clean room, so I was unable to get a resonance frequency measurement on Thursday. The hope is that because the proof mass remained locked when the flexures broke, the HoQI should hopefully still be mostly aligned with the CRS and only need small adjustments which will be done this week.

SEI

Images attached to this report

H1 ISC - Comment to Using SQZ to check BS alignment

betsy.weaver@ligo.org — Mon, 22 Jun 2026 09:46:36 -0700

Author: betsy.weaver@ligo.org

Report ID: 90688

This was supposed to say

SR3 - Use OPLEV pointing from THUR 5pm (when ISI came back on)

LHO VE - Purge Air Dewpoint Check (6/19/26)

jordan.vanosky@ligo.org — Mon, 22 Jun 2026 09:20:46 -0700

Author: jordan.vanosky@ligo.org

Report ID: 90687

Late entry from Friday night.

Jordan, Gerardo (remote), Betsy (remote)

On Friday night (6/19) Gerardo noticed the purge air dewpoint had risen above our -40C requirement and continued to rise. Out of precaution, I came on to the site to check the purge air status and see if any HAM/BSC door covers had blown off the flange.

All door covers were in place, so no issue there. I then isolated the purge air from the lvea for ~30 minutes, therefore dropping the demand/duty cycle of the air comporessor, to see if the dewpoint changed. It slowly began to drop and I took local dewpoint measurements at the sample port just past the filters on the purge air skid. There was no significant difference in dewpoint when the drying towers cycled, the dewpoint remained around -38C regardless of which tower was drying.

After ~30 minutes, the dewpoint had dropped to -43C and so I reopened the purge air to the lvea, then reduced the flow at the purge air port on the output tube. It seems there was just too much demand on the compressor.

As of this morning, the dewpoint has returned to normal -51C at the drying towers.

Images attached to this report

H1 General - OPS Monday Day shift start

ryan.crouch@ligo.org — Mon, 22 Jun 2026 07:34:23 -0700

Author: ryan.crouch@ligo.org

Report ID: 90686

TITLE: 06/22 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: MAINTENANCE
Wind: 17mph Gusts, 10mph 3min avg
Primary useism: 0.04 μm/s
Secondary useism: 0.09 μm/s
QUICK SUMMARY:

HAM7 work, CRS work, possibly more FARO HEPI alignment planned for today
IFO alignment checks

H1 CDS - Comment to PID control of CP1 pump LN2 level looking good

david.barker@ligo.org — Mon, 22 Jun 2026 07:14:08 -0700

Author: david.barker@ligo.org

Report ID: 90685

Here is the last two days trends, CP1 LN2 level is holding at 92.00 +/- 0.05 %

Images attached to this report

H1 ISC - Comment to Measurement of jitter with IMC WFS at 10W

jennifer.wright@ligo.org — Sun, 21 Jun 2026 23:30:43 -0700

Author: jennifer.wright@ligo.org

Report ID: 90684

Just adding a note with the comparison I used for my GWADW talk on May 19th so its in the alog.

I did an injection into the yaw DOF of the PZT mirror in the PSL and measured the response on the IMC REFL QPD DC when locked, since this was used to do jitter injections to produce noise plots during O4 I could compare to a time when we did this measurement during NLN without JAC, and locked at 10W with JAC.

The power difference shouldn't matter since I am doing a transfer function, but unfortunately the injection I did was not high enough to see coherence in the IMC REFL WFS QPDs and I ran out of time to repeat the measurement in March due to corner re-alignment efforts.

The two times I chose were:

60W lock without JAC: 07-08-2025 21:47:59 UTC - approx 16 minutes.

2W lock with JAC: 18-03-2026 22:28:12 UTC - approx. 16 minutes.

The graph which compares WFS B QPD with old measurement in blue and new in orange can be used to put a lower limit on the suppression of JAC. It gives a minimum jitter reduction of 0.15 at 10Hz.

I would like to redo this once we pump down the corner sufficiently to do some measurements with the main laser.

The txml measurement files that contain the data I used for this are in /ligo.home/jennfioer.wright/git/2026/JAC/JAC_PZT_Y_inj.xml for the new measurement and the same folder but the file 20250807_IMC_WFS_PZT_Y.xml for the older measurement.

Images attached to this report