aLIGO LHO Logbook

H1 IOO - Comment to ISS vertical calibration

jennifer.wright@ligo.org — Mon, 06 Oct 2025 13:04:59 -0700

Author: jennifer.wright@ligo.org

Report ID: 87324

From the vertical scan of the PD array it looks like diodes 2 and 6, which are in a vertitcal line in the array, are not properly aligned. We are not sure if this is an issue with one of the beam baths through the beamsplitters/mirrors that split the light onto the four directions for each vertical pair of diodes or if these diodes are just aligned wrongly.

H1 IOO - Comment to ISS vertical calibration

jennifer.wright@ligo.org — Mon, 06 Oct 2025 13:02:33 -0700

Author: jennifer.wright@ligo.org

Report ID: 87323

Keita did a few more measurements in the verticall scan after I left on Friday, attached is the updated scan plot.

He also then set the pitch to the middle of the range (165mm on the scale in the graph) and took a horizontal scan of the PD array using the micrometer that the PZT mirror is mounted on. See second graph.

Images attached to this report

H1 SQZ - Comment to SFI2 temperature with ZM fringe wrapping measurements

sheila.dwyer@ligo.org — Mon, 06 Oct 2025 12:38:45 -0700

Author: sheila.dwyer@ligo.org

Report ID: 87322

Here's a model of our ZM fringe wrapping measurements (the same plot as in 86836, plotted with a model that's roughly emulating Valera's measurement above. It looks like LLO has about 200pW of interferometer light reaching the filter cavity, but none of the extra scatter we see from before SFI2.

Images attached to this report

H1 TCS - New HWS Refs Taken at 2W and 60W

camilla.compton@ligo.org — Mon, 06 Oct 2025 12:30:28 -0700

Author: camilla.compton@ligo.org

Report ID: 87321

Matt, Camilla

As we took new HWS references at 25W last week while troubleshooting HWS (87234, 87252), today we tried to take new references while at 2W today. I did this after the green beams were shuttered around CHECK_VIOLINS_FOR_POWERUP.

However ITMX signal looked very noisy, so Matt and I removed 3 dead pixels, following the wiki. For this to take effect we needed to again take new references, so we said this at 60W just for ITMX. The reported spherical power diopters shouldn't be trusted for ITMX, but relative change in diopters will be fine.

H1 General - H1 Back to Observing

ryan.short@ligo.org — Mon, 06 Oct 2025 12:09:18 -0700

Author: ryan.short@ligo.org

Report ID: 87319

H1 is back to observing as of 19:06 UTC after dropping at 15:30 UTC for planned commissioning. There was a lockloss during that time, possibly from commissioning activities, that was simple to relock from after running an initial alignment.

H1 TCS - TCS Monthly Trends

ryan.crouch@ligo.org — Mon, 06 Oct 2025 11:30:31 -0700

Author: ryan.crouch@ligo.org

Report ID: 87315

Last checked in alog86721, closes FAMIS28465.

The CO2s look fine although the flow for ITMX seems more variable than ITMY.

For the HWSs ITMX_SLEDPOWERMON is trending downwards, it passed the scope cursor Y=1mW on 9/17/25 ~10:21 UTC. ITMY is also trending downward, as they both were during the last check. From the ~ the 10th 19:07 UTC to the 16th the HWS spherical power dropped, which tracks as starting due to the power outage.

Images attached to this report

H1 SQZ - Comment to filter cavity length and backscatter

sheila.dwyer@ligo.org — Mon, 06 Oct 2025 11:29:51 -0700

Author: sheila.dwyer@ligo.org

Report ID: 87318

I posted this as a comment on the wrong alog on Friday, adding it here now. Also see follow up measurements with changes to SFI2 temperature, and the comparison measurement from LLO 87309

Power level heading towards HAM7 from OFI:

The power on the DCPDs is 47mW, and there is 12pW retro-reflected off the filter cavity, so the total isolation provided by OFI + SFI2 + SFI1 is 2.5e-10 in power ratio, or 96dB. The OFI isolation ratio was measured to be 43dB in 79379. If this is true it would imply that one of the SFIs is providing less than the 30dB isolation assumed in T1800447, and we should have 2uW of carrier light headed towards SFI2.

Our readback of the 1% pick off of light from the interferometer heading towards SFI2, B:PD1 (OFI PD A) says that we have 0.03mW on it, meaning 3mW from the IFO going towards SFI2, about 1mW of this would be carrier based on (87114),which seems too high.

The responsivity of this PD was checked in 60284, and later double checked because it seemed low (the settings are still the same). The similar PD OFI PDB has a measured responsivity of 0.25A/W and the excelitas website lists a peak responsivity of 0.6A/W at 850nm for these PDs. (ffd-200h-si-pin) If we think that this calibration was mistaken and the real responsivity is more like OFI PD B, 0.25A/W, there is 0.72 mW of light from the OFI heading towards SFI2, ~240 uW of carrier, the OFI isolation would only be 23dB, and the SFIs must be providing something like 36 dB each.

Reflectivity:

If my interpretation of the fringe wrapping measurements into power are correct (12 nW of power is retroreflected from the path that includes ZM5), we are reflecting 50ppm of the carrier scattered toward HAM7 using the (recalibrated) 240uW value from OFI PDB, or 0.6% if we believe the isolation ratio measurement for the OFI and use the 2uW value. B:BS1 is a 1%, so the maximum reflectivitiy we could get from scatter in the B:PD1 path would be 0.01%. This means that the B:PD1 path can't explain the reflectivity needed if there is 2uW headed towards HAM7, and even if there is 240uW heading towards HAM7 this PD seems unlikely to explain the scatter, since it would need to reflect half the light that's incident on the PD. Camilla did alog the check of the alignment (and the beam dump catching the retro-reflection off this diode: 65006)

LHO VE - Mon CP1 Fill

david.barker@ligo.org — Mon, 06 Oct 2025 11:18:15 -0700

Author: david.barker@ligo.org

Report ID: 87317

Mon Oct 06 10:05:25 2025 INFO: Fill completed in 5min 22secs

Images attached to this report

H1 ISC - Instructions to run a single bounce OMC scan

matthewrichard.todd@ligo.org — Mon, 06 Oct 2025 11:17:10 -0700

Author: matthewrichard.todd@ligo.org

Report ID: 87316

M. Todd, S. Dwyer

I'm sure there are other sources for this instruction set, but it will serve me later having written this out -- lending some muscle memory hopefully. We are interested in taking several OMC scans over the next couple weeks to estimate mode-matching of various cavities to the OMC in comparison to our models.

Step 1: Suspension Settings for the TMs and PRM/SRM:

Going to sitemap > ASC > IFO Align Compact , you can find shortcuts for each of the suspensions. We will want to take both the ETMs to misaligned as well as the PRM and SRM. If we want to do a single bounce with ITMX, we misalign ITMY and vice-versa.

To misalign an optic from IFO Align Compact, click on the full optic suspension shortcut with the corresponding optic name (e.g. overlapping squares + "ETMX"). At the top of the suspension screen, take the guardian state to misaligned.

Step 2: Turn on ASC centering loops for the OMs

Going to sitemap > ASC > ASC Overview > DC Centering (middle screen), turn on the inputs to DC3 and DC4 pitch and yaw loops.

Make sure that the inputs to the centering loops start to go to zero and the outputs are not blowing up to infinity.

Then go to sitemap > OMC > OMC Overview > fast shutter and ensure that the status reads open, otherwise, hit open.

Step 3: Turn on OMC ASC and set gains and offsets

Going to sitemap > GRD > ISC Overview find the OMC guardian and take it to ASC_QPD_ON

Going to sitemap > OMC > OMC control, set the MASTER GAIN to 0.02 and bring the LSC offset to the far left ( -50.0 ).

Step 4: Go out and turn off the sidebands (9, 45, 118 MHz)

Going out to the PSL racks, in the far right stack towards the bottom find the EOM drivers labeled 9MHz and 45MHz and flick the switch on the panel to OFF

Then below the RF Combiner Amplifier, unplug the cable going to the BNC port label 118 MHz.

Step 5: Run OMC scan

An example can be found in my templates /ligo/home/matthewrichard.todd/Templates/omc/20251006_OMC_scan.xml

Open the template with DTT and save it as another copy, naming it with whatever date you are running it plus any notes.

Images attached to this report

H1 SUS - Roll mode damping notes

elenna.capote@ligo.org — Mon, 06 Oct 2025 10:53:30 -0700

Author: elenna.capote@ligo.org

Report ID: 87314

Ryan S, Elenna

Today the roll mode was a bit high, and was rung up further during the SFI testing that Sheila and Camilla ran. We have found its best practice to turn the roll mode damping off when these injections are happening.

Once the injections finished, we turned the damping back on, and it seemed like the mode was either not damping or getting slightly worse. We turned the damping off for seven minutes, and saw that the mode clearly rung up much faster. So, we reengaged the damping, and then tried a slightly higher gain of 42 and then 45 and saw that the mode actually did start to come back down.

So, in short, if a gain of 40 is not bringing the mode down fast enough, it seems like we can at least tolerate a gain of 45. I can't remember if this is an SDF or not, but I know it is guardian controlled to be 40. Tagging opsinfo in case this is useful information.

OpsInfo

H1 IOO - Coupling measurements from the 30th September with higher dither amplitude

jennifer.wright@ligo.org — Mon, 06 Oct 2025 10:48:46 -0700

Author: jennifer.wright@ligo.org

Report ID: 87276

Rahul, Jennie W, Keita

Just catching up on historical alogs

We increased the dither amplitude to 1Vpp to give us better coherence in our horizontal input dither -> PD array RIN measurement compared to our previous alog (#87140).

We got pretty good coherences on PDs 2,3 5 -8. All of these measured between about 0.1 per m and 30 per m RIN.

After showing the results to Keita he got us to do two more measurements where we changed the input alignment yaw either side of the nominal to see if this had the expected results on the magnitude and phase of the transfer function.

The results are shown in the attached graphs, PD number is on the x axis and Magnitude, phase and coherence of each measurement are on the 3 y-axis. The measurements with the input aligned are shown in blue.

To get the two other measurements I looked at the two leeft-most diodes on the array (I think these are 4 on the top and 8 on the bottom) with the beam viwer as Rahul moved the PZT steering mirror in yaw.

For these three measuremenrts Keita pointed out that the discrepancy between the diodes phases didn't make much sense.

ISC, PSL

Images attached to this report

H1 ISC - Comment to Camera spot calibration

elenna.capote@ligo.org — Mon, 06 Oct 2025 10:23:19 -0700

Author: elenna.capote@ligo.org

Report ID: 87313

I continued today following the same process stated above.

	Camera offset	A2L gain	Conversion
ETMX P	start: -173, end: -172	start: 3.04, end: 2.92	(-9.38 mm - -9.93 mm)/ 1ct = 0.55 mm/ct
ETMY Y	start: -349.5, end: -348.5	start: 1.41, end: 1.06	(3.90 mm - 5.18 mm) / 1ct = -1.28 mm/ct
ETMX Y	start: -422, end: -421	start: 4.85, end: 4.68	(17.22 mm - 17.84 mm) = -0.62 mm/ct

H1 PSL - PSL 10-Day Trends

ryan.short@ligo.org — Mon, 06 Oct 2025 09:53:09 -0700

Author: ryan.short@ligo.org

Report ID: 87312

FAMIS 31106

PMC REFL has been continuing to increase, but nothing much of note this week otherwise.

Images attached to this report

H1 SQZ - Comment to SFI2 temperature with ZM fringe wrapping measurements

valery.frolov@ligo.org — Mon, 06 Oct 2025 09:52:54 -0700

Author: valery.frolov@ligo.org

Report ID: 87311

The attached plot shows ZM2 and ZM5 fringing measurements at LLO. The total OMC current is 50 mA.

Images attached to this report

LHO General - Comment to Ops Day Shift Summary

camilla.compton@ligo.org — Mon, 06 Oct 2025 09:06:34 -0700

Author: camilla.compton@ligo.org

Report ID: 87310

This SQZ Lockloss was caused by the OPO PZT running out of range. Plot attached, when the OPO relocked with the PZT at ~100V, the SQZ angle servo worked as expected to bring the range back.

SQZ

Images attached to this report

H1 SQZ - SFI2 temperature with ZM fringe wrapping measurements

sheila.dwyer@ligo.org — Mon, 06 Oct 2025 09:06:15 -0700

Author: sheila.dwyer@ligo.org

Report ID: 87309

Camilla, Sheila

We repeated a test similar to 78125, where we changed the SFI2 temperature and measured fringe wrapping by exciting ZM2 and ZM5. The temperature of SFI2 changes the backscatter shelf amplitude seen when exciting ZM2, but not ZM5, suggesting that the source of the scattering is upstream of the isolation of SFI2.

Images attached to this report

H1 SQZ - Comment to ZM2,5 Fridge Wrapping with No SQZ light and Different Alignments on OFI_PD_A

camilla.compton@ligo.org — Mon, 06 Oct 2025 08:51:08 -0700

Author: camilla.compton@ligo.org

Report ID: 87308

To turn off the roll mode damping: sitemap > SUS > Bounce Roll > DAMPING Filters. Then turn the gain of the one damping to zero (already should be a 10s Tramp).

Images attached to this report

LHO General - Ops Day Shift Start

ryan.short@ligo.org — Mon, 06 Oct 2025 07:39:47 -0700

Author: ryan.short@ligo.org

Report ID: 87307

TITLE: 10/06 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 3mph Gusts, 2mph 3min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.09 μm/s
QUICK SUMMARY: H1 has been locked for 37.5 hours. Commissioning time scheduled today from 15:30 to 18:30 UTC.

Wind and microseism low
All other systems nominal

H1 General - Sunday Ops Eve Shift End

anthony.sanchez@ligo.org — Sun, 05 Oct 2025 22:07:01 -0700

Author: anthony.sanchez@ligo.org

Report ID: 87306

TITLE: 10/06 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 156Mpc
INCOMING OPERATOR: Ryan C
SHIFT SUMMARY:
H1 has been locked for 28 hrs, currently Observing.
I Have nothing else to report.

LOG:
No Log

H1 General - Sunday Ops Eve Shift Start

anthony.sanchez@ligo.org — Sun, 05 Oct 2025 16:35:01 -0700

Author: anthony.sanchez@ligo.org

Report ID: 87305

TITLE: 10/05 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 155Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 16mph Gusts, 10mph 3min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.11 μm/s
QUICK SUMMARY:
H1 is Locked and Observing & I've got no plans to change that.

LHO General - Ops Day Shift Summary

ryan.short@ligo.org — Sun, 05 Oct 2025 16:30:02 -0700

Author: ryan.short@ligo.org

Report ID: 87304

TITLE: 10/05 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 156Mpc
INCOMING OPERATOR: Tony
SHIFT SUMMARY: Very quiet day with H1 observing throughout; nothing of consequence to report. H1 has been locked for 22.5 hours.

LHO General - Ops Day Mid-Shift Report

ryan.short@ligo.org — Sun, 05 Oct 2025 12:02:49 -0700

Author: ryan.short@ligo.org

Report ID: 87303

State of H1: Observing at 158Mpc

H1 has been locked for 18 hours; quiet morning so far with no drops from observing.

LHO VE - Sun CP1 Fill

david.barker@ligo.org — Sun, 05 Oct 2025 10:40:37 -0700

Author: david.barker@ligo.org

Report ID: 87302

Sun Oct 05 10:07:49 2025 INFO: Fill completed in 7min 45secs

Images attached to this report

LHO General - Ops Day Shift Start

ryan.short@ligo.org — Sun, 05 Oct 2025 07:45:24 -0700

Author: ryan.short@ligo.org

Report ID: 87301

TITLE: 10/05 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 156Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 13mph Gusts, 9mph 3min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.11 μm/s
QUICK SUMMARY: H1 has been locked for 13.5 hours. One drop from observing last night at 09:21 UTC from SQZ dropping out, but look like everything came back fine.

Wind moderately low, microseism low and still dropping
All other systems nominal

H1 General - Saturday Night Eve Shift End

anthony.sanchez@ligo.org — Sat, 04 Oct 2025 22:04:30 -0700

Author: anthony.sanchez@ligo.org

Report ID: 87300

TITLE: 10/05 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 155Mpc
INCOMING OPERATOR: Ryan C
SHIFT SUMMARY:
One Lockloss @23:44 UTC & fairly easy relocked.
Back to Observing at 1:06 UTC.
H1 has been locked for 4 Hours.

LOG:
No Log

H1 General - Lockloss and relock

anthony.sanchez@ligo.org — Sat, 04 Oct 2025 19:57:59 -0700

Author: anthony.sanchez@ligo.org

Report ID: 87299

Unknown Lockloss.
H1:LSC-DARM_IN1_DQ seemed to be the first channel that takes an excursion.

Relocking notes:
Relocking was striaght forward, but had to send Y-ARM to Increase flashes. Otherwise it didn't give me any hassle.

Lockloss

Images attached to this report

H1 General - Satuday Night Ops Shift

anthony.sanchez@ligo.org — Sat, 04 Oct 2025 16:37:10 -0700

Author: anthony.sanchez@ligo.org

Report ID: 87298

TITLE: 10/04 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 74Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 10mph Gusts, 5mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.14 μm/s
QUICK SUMMARY:

H1 Has been locked for 27 Hours and is currently Observing.
The plan is to continue to Observe the universe for as long as possible.

LHO General - Ops Day Shift Summary

ryan.short@ligo.org — Sat, 04 Oct 2025 16:30:02 -0700

Author: ryan.short@ligo.org

Report ID: 87297

TITLE: 10/04 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 150Mpc
INCOMING OPERATOR: Tony
SHIFT SUMMARY: H1 remained lock the whole day with only a few drops from observing, most of which were intentional. After the squeezer relocked, the range was a bit low, but the SQZ angle servo eventaully brought it back up over the course of about an hour. I probably could have run a SQZ angle scan right before going back into observing to fix the range sooner. H1 has now been locked for 27 hours.
LOG:

15:56 - Dropped observing to engage hi-gain ASC to ride through a M6.0 EQ from Japan
16:06 - Observing
18:33 - Dropped observing for calibration - alog87295
19:05 - Observing
21:02 - Dropped observing from SQZ FC unlocking
- Guardians restored everything automatically
21:06 - Observing

H1 SEI - Ground Seismometer Mass Position Check - Monthly

ryan.short@ligo.org — Sat, 04 Oct 2025 13:00:05 -0700

Author: ryan.short@ligo.org

Report ID: 87296

FAMIS 27375, last checked in alog86751

There are 13 T240 proof masses out of range ( > 0.3 [V] )!
ETMX T240 2 DOF X/U = -1.57 [V]
ETMX T240 2 DOF Y/V = -1.466 [V]
ETMX T240 2 DOF Z/W = -1.024 [V]
ITMX T240 1 DOF X/U = -2.176 [V]
ITMX T240 1 DOF Z/W = 0.432 [V]
ITMX T240 3 DOF X/U = -2.304 [V]
ITMY T240 3 DOF X/U = -1.084 [V]
ITMY T240 3 DOF Z/W = -2.75 [V]
BS T240 1 DOF Y/V = -0.375 [V]
BS T240 3 DOF Y/V = -0.301 [V]
BS T240 3 DOF Z/W = -0.46 [V]
HAM8 1 DOF Y/V = -0.503 [V]
HAM8 1 DOF Z/W = -0.821 [V]

All other proof masses are within range ( < 0.3 [V] ):
ETMX T240 1 DOF X/U = -0.091 [V]
ETMX T240 1 DOF Y/V = -0.146 [V]
ETMX T240 1 DOF Z/W = -0.159 [V]
ETMX T240 3 DOF X/U = -0.122 [V]
ETMX T240 3 DOF Y/V = -0.182 [V]
ETMX T240 3 DOF Z/W = -0.153 [V]
ETMY T240 1 DOF X/U = -0.029 [V]
ETMY T240 1 DOF Y/V = 0.131 [V]
ETMY T240 1 DOF Z/W = 0.192 [V]
ETMY T240 2 DOF X/U = -0.118 [V]
ETMY T240 2 DOF Y/V = 0.177 [V]
ETMY T240 2 DOF Z/W = -0.007 [V]
ETMY T240 3 DOF X/U = 0.187 [V]
ETMY T240 3 DOF Y/V = -0.021 [V]
ETMY T240 3 DOF Z/W = 0.078 [V]
ITMX T240 1 DOF Y/V = 0.223 [V]
ITMX T240 2 DOF X/U = 0.128 [V]
ITMX T240 2 DOF Y/V = 0.229 [V]
ITMX T240 2 DOF Z/W = 0.189 [V]
ITMX T240 3 DOF Y/V = 0.078 [V]
ITMX T240 3 DOF Z/W = 0.087 [V]
ITMY T240 1 DOF X/U = 0.022 [V]
ITMY T240 1 DOF Y/V = 0.077 [V]
ITMY T240 1 DOF Z/W = -0.058 [V]
ITMY T240 2 DOF X/U = 0.012 [V]
ITMY T240 2 DOF Y/V = 0.196 [V]
ITMY T240 2 DOF Z/W = 0.074 [V]
ITMY T240 3 DOF Y/V = 0.037 [V]
BS T240 1 DOF X/U = -0.122 [V]
BS T240 1 DOF Z/W = 0.121 [V]
BS T240 2 DOF X/U = 0.037 [V]
BS T240 2 DOF Y/V = 0.122 [V]
BS T240 2 DOF Z/W = 0.013 [V]
BS T240 3 DOF X/U = -0.204 [V]
HAM8 1 DOF X/U = -0.206 [V]

There are 2 STS proof masses out of range ( > 2.0 [V] )!
STS EY DOF X/U = -4.609 [V]
STS EY DOF Z/W = 2.244 [V]

All other proof masses are within range ( < 2.0 [V] ):
STS A DOF X/U = -0.456 [V]
STS A DOF Y/V = -0.864 [V]
STS A DOF Z/W = -0.523 [V]
STS B DOF X/U = 0.179 [V]
STS B DOF Y/V = 0.945 [V]
STS B DOF Z/W = -0.348 [V]
STS C DOF X/U = -0.692 [V]
STS C DOF Y/V = 0.751 [V]
STS C DOF Z/W = 0.533 [V]
STS EX DOF X/U = -0.214 [V]
STS EX DOF Y/V = -0.152 [V]
STS EX DOF Z/W = 0.079 [V]
STS EY DOF Y/V = 1.242 [V]
STS FC DOF X/U = 0.198 [V]
STS FC DOF Y/V = -1.122 [V]
STS FC DOF Z/W = 0.607 [V]

H1 CAL - Broadband and Simulines Calibration Sweeps

ryan.short@ligo.org — Sat, 04 Oct 2025 12:09:15 -0700

Author: ryan.short@ligo.org

Report ID: 87295

Following instructions from the TakingCalibrationMeasurements wiki, at 18:33 UTC I dropped H1 out of observing to run the usual calibration sweeps. Calibration monitor and report attached.

Broadband - 18:34:20 to 18:39:38 UTC

Simulines - 18:40:57 to 19:04:04 UTC

File written out to: /ligo/groups/cal/H1/measurements/DARMOLG_SS/DARMOLG_SS_20251004T184057Z.hdf5
File written out to: /ligo/groups/cal/H1/measurements/PCALY2DARM_SS/PCALY2DARM_SS_20251004T184057Z.hdf5
File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L1_SS/SUSETMX_L1_SS_20251004T184057Z.hdf5
File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L2_SS/SUSETMX_L2_SS_20251004T184057Z.hdf5
File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L3_SS/SUSETMX_L3_SS_20251004T184057Z.hdf5

Images attached to this report

Non-image files attached to this report

H1_calibration_report_20251004T184057Z.pdf

LHO VE - Sat CP1 Fill

david.barker@ligo.org — Sat, 04 Oct 2025 10:10:57 -0700

Author: david.barker@ligo.org

Report ID: 87294

Sat Oct 04 10:07:34 2025 INFO: Fill completed in 7min 30secs

Images attached to this report

LHO General - Ops Day Shift Start

ryan.short@ligo.org — Sat, 04 Oct 2025 07:49:54 -0700

Author: ryan.short@ligo.org

Report ID: 87293

TITLE: 10/04 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 4mph Gusts, 2mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.20 μm/s
QUICK SUMMARY: H1 has been locked for 18 hours. Looks like an EQ from Guatemala put us into EQ mode about 5 hours ago, but otherwise no issues overnight.

Wind low, microsiesm steady just above 50th percentile
All other systems nominal

H1 General - Ops EVE Shift End

oli.patane@ligo.org — Fri, 03 Oct 2025 22:00:12 -0700

Author: oli.patane@ligo.org

Report ID: 87292

TITLE: 10/04 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 154Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY: Observing at 155 Mpc and have been Locked for almost 8.5 hours. Quiet shift with nothing to report
LOG:

no log

H1 General - Ops EVE Midshift Status

oli.patane@ligo.org — Fri, 03 Oct 2025 20:07:25 -0700

Author: oli.patane@ligo.org

Report ID: 87291

Observing at 151 Mpc and have been locked for over 6.5 hours. Nothing to report

H1 IOO - ISS vertical calibration

jennifer.wright@ligo.org — Fri, 03 Oct 2025 18:17:06 -0700

Author: jennifer.wright@ligo.org

Report ID: 87290

Jennie W, Keita,

Since we don't have an easy way of scanning the input beam in the vertical direction, Keita used the pitch of the PZT steering mirror to do the scan and we read out the DC voltages for each PD.

The beam position can be inferred from the pictures setup - see photo. As the pitch actuator on the steering mirror is rotated the allen key which is in the hole in the pitch actuator moves up and down relative to the ruler.

height on ruler above table = height of centre of actuator wheel above table + sqrt((allen key thickness/2)^2 + (allen key length)^2) *np.sin(ang - delta_theta)

where ang is the angle the actuator wheel is at and delta_theta is the angle from the centre line of the allen key to its corner which is used to point at the gradations on the ruler.

The first measurement from our alignment that Keita found yesterday that minimised the vertical dither coupling is shown. It shows voltage on each PD vs. height on the ruler.

From this and from the low DC voltages we saw on the QPD and some PDs yesterday Keita and realised we had gone too far to the edge of the QPD and some PDs.

So in the afternoon Keita realigned onto all the of PDs.

Today as we were doing measurements on it Keita realised we still had the small aperture piece in place on the array so we moved that for our second set of measurements.

The plot of voltage with ruler position and voltage with pitch wheel angle are attached.

ISC, PSL

Images attached to this report

H1 SQZ - Comment to filter cavity backscatter measurements

sheila.dwyer@ligo.org — Fri, 03 Oct 2025 16:49:17 -0700

Author: sheila.dwyer@ligo.org

Report ID: 87274

Here's the plot of the fringe wrapping measurements in displacement units. It can be compared to a similar measurement made on ZM4 + 5 at LLO: 60856. Over email Peter asked some questions about the power levels needed to explain this.

Power level heading towards HAM7 from OFI:

Reflectivity:

Images attached to this report

LHO General - Ops Day Shift Summary

ryan.short@ligo.org — Fri, 03 Oct 2025 16:30:19 -0700

Author: ryan.short@ligo.org

Report ID: 87288

TITLE: 10/03 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 149Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY: One lockloss due to an earthquake today that kept H1 down for a while, but relocking after that was mostly straightforward; not much else to report today. H1 has now been locked for 3 hours.

16:26 - Dropped observing to engage hi-gain ASC to hopefully ride out EQ
16:44 - Lockloss from EQ - alog87278
18:02 - Starting initial alignment
18:28 - IA finished
20:34 - Observing

LOG:

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
22:52	SAF	Laser HAZARD	LVEA	YES	LVEA is Laser HAZARD	Ongoing
14:38	FAC	Randy	X-arm	N	BT inspection	19:37
17:34	ISC	Keita	Opt Lab	Local	ISS array work	19:26
17:41	PEM	Anamaria	CER	N	Checking an accelerometer	17:44
17:50	JAC	Corey	JAC Lab	N	JAC table work	20:29
18:23	ISC	Jennie	Opt Lab	Local	ISS array work	19:26
18:48	PEM	Robert, Anamaria, Alicia, Rene	LVEA	-	PEM things	19:26
19:26	PEM	Robert	LVEA	-	Placing shaker near BSC8	19:42
21:33	JAC	Corey	JAC Lab	N	JAC table work	23:07
21:34	ISC	Keita, Jennie	Opt Lab	Local	ISS array work - Jennie out @ 22:08	22:24

H1 General - Ops EVE Shift Start

oli.patane@ligo.org — Fri, 03 Oct 2025 16:06:31 -0700

Author: oli.patane@ligo.org

Report ID: 87287

TITLE: 10/03 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 20mph Gusts, 15mph 3min avg
Primary useism: 0.04 μm/s
Secondary useism: 0.19 μm/s
QUICK SUMMARY:

Observing at 153 Mpc and have been Locked for 2.5 hours

H1 ISC - BS HEPI RX and RY injections show extra light

anamaria.effler@ligo.org — Fri, 03 Oct 2025 15:19:10 -0700

Author: anamaria.effler@ligo.org

Report ID: 87286

Robert, Anamaria

Following up on tests done at L1, we wanted to do the same tests at H1 and compare. We see similar large shelves when we shake RX and RY at 0.2 Hz. This mechanism is not directly limiting DARM since we have to inject a lot to see it, but it allows us to estimate how much light is around the BS area available for scattering into DARM.

The stranger difference between the sites is that the ratio of the first shelf to the second shelf for H1 is much smaller, circa 10, so implies a second reflective path that's still fairly in line (eg like the R0 ESD reflections).

I drove 100 cts into the the corresponding ISO filter bank.

RX injection start: Oct 2 17:41:39 utc
duration: 8 min

RY injection start: Oct 2 17:58:20 utc
duration: 2 min (lost lock shortly after so weren't able to get more data)

dtts can be found in /ligo/home/anamaria.effler/ddt/ with suggestive names. I had also copied over the equivalent L1 dtts in the same directory.

Robert will folow up with some more tests.

AOS, ISC, PEM

Images attached to this report

H1 SEI - ISI CPS Noise Spectra Check Weekly FAMIS

oli.patane@ligo.org — Fri, 03 Oct 2025 14:42:36 -0700

Author: oli.patane@ligo.org

Report ID: 87285

Closes FAMIS#26659, last checked 87238

HAM5, HAM6, HAM8, ITMX ST1, ITMY ST1 - bit of extra noise between 5-8 Hz in all sensors
BS ST1 - excess noise between 5-8 Hz in vertical sensors
ETMX ST1 - excess noise between 20-30 Hz in V3

Non-image files attached to this report

CPS_spectra_14:28-10_03_2025.pdf

LHO FMCS - HVAC Fan Vibrometers Check FAMIS

oli.patane@ligo.org — Fri, 03 Oct 2025 14:27:39 -0700

Author: oli.patane@ligo.org

Report ID: 87284

Closes FAMIS#27426, last checked 87179

Corner Station Fans (attachment1)
- All fans are looking normal and within range.

Outbuilding Fans (attachment2)
- All fans are looking normal and are within range. You can see when EX fan 2 was turned off three days ago due to its noise increasing (issue fixed).

PEM

Images attached to this report

H1 PSL - PSL Status Report - Weekly

ryan.short@ligo.org — Fri, 03 Oct 2025 14:07:00 -0700

Author: ryan.short@ligo.org

Report ID: 87283

FAMIS 27397

Laser Status:
NPRO output power is 1.861W
AMP1 output power is 69.83W
AMP2 output power is 138.5W
NPRO watchdog is GREEN
AMP1 watchdog is GREEN
AMP2 watchdog is GREEN
PDWD watchdog is GREEN

PMC:
It has been locked 10 days, 2 hr 57 minutes
Reflected power = 25.18W
Transmitted power = 104.1W
PowerSum = 129.3W

FSS:
It has been locked for 0 days 2 hr and 15 min
TPD[V] = 0.5335V

ISS:
The diffracted power is around 3.9%
Last saturation event was 0 days 4 hours and 21 minutes ago

Possible Issues:
PMC reflected power is high

H1 General - Comment to Lockloss @ 16:44 UTC - EQ

ryan.short@ligo.org — Fri, 03 Oct 2025 13:37:31 -0700

Author: ryan.short@ligo.org

Report ID: 87282

H1 back to observing at 20:34 UTC. Ran an alignment after the ground motion calmed down, then while locking, two locklosses during DRMI acquisition made for a longer overall relock time. MICH_FRINGES was needed after the second DRMI lockloss.

H1 CDS - Comment to Seismic activity bar added to top of CDS Overview MEDM

david.barker@ligo.org — Fri, 03 Oct 2025 10:46:03 -0700

Author: david.barker@ligo.org

Report ID: 87281

DTS Environment Repositioned On CDS Overview.

To make room for the Seismic bar, I removed the DTS environment section. This has now been added back as a "system widget" in the FMCS section (see attached).

The "DTS ENV" block will turn RED if the server room temperature exceeds 80F. The block will turn MAGENTA if the dts_env_ioc GPS time falls behind by 10 minutes or more.

Clicking on the "DTS ENV" block will open the DTS Detail MEDM (attached).

Images attached to this report

LHO VE - Fri CP1 Fill

david.barker@ligo.org — Fri, 03 Oct 2025 10:17:08 -0700

Author: david.barker@ligo.org

Report ID: 87280

Fri Oct 03 10:07:45 2025 INFO: Fill completed in 7min 41secs

Images attached to this report

H1 CDS - New script to list Guardian source files which have been modified but not loaded into nodes

david.barker@ligo.org — Fri, 03 Oct 2025 10:11:50 -0700

Author: david.barker@ligo.org

Report ID: 87279

I have written a new script called guardian_modified_not_loaded which lists those Guardian nodes using a source file which has been modified but not loaded into that node.

The reason this is important is that when a guardian node is restarted, it reads the latest userapps files which could differ from what was being used before the restart.

Running the script today, for example, shows that lscparams.py and sqzparams.py, which are used by many nodes, have been modified and only loaded into a few nodes.

We plan on running this script regularly, and especially before a scheduled reboot of h1guardian1.

Current stats are: number of source files = 270, number of guardian nodes = 173, total nodes file count = 1761

Loaded 270 opt/ file checksums from /opt/rtcds/lho/h1/data/guardian_files/current Loaded 173 nodes from /opt/rtcds/lho/h1/data/guardian_files/current.yaml No node_exceptions.yaml file found - no exceptions applied

================================================ Node Status File ================================================ ALS_COMM NOT LOADED lscparams.py ALS_XARM NOT LOADED lscparams.py ALS_YARM NOT LOADED lscparams.py CAMERA_SERVO NOT LOADED lscparams.py H1_MANAGER NOT LOADED lscparams.py IMC_LOCK NOT LOADED lscparams.py INIT_ALIGN NOT LOADED lscparams.py ISC_DRMI NOT LOADED lscparams.py LASER_PWR NOT LOADED lscparams.py LOCKLOSS_SHUTTER_CHECK NOT LOADED lscparams.py OMC_LOCK NOT LOADED lscparams.py SEI_CONF NOT LOADED lscparams.py SEI_ENV NOT LOADED lscparams.py SQZ_ANG_ADJUST NOT LOADED sqzparams.py SQZ_CLF_LR NOT LOADED sqzparams.py SQZ_FC NOT LOADED lscparams.py SQZ_MANAGER NOT LOADED lscparams.py TCS_ITMX_CO2_PWR NOT LOADED lscparams.py TCS_ITMY_CO2_PWR NOT LOADED lscparams.py TEST NOT LOADED lscparams.py THERMALIZATION NOT LOADED lscparams.py NOT LOADED sqzparams.py TMS_SERVO NOT LOADED lscparams.py VIOLIN_DAMPING NOT LOADED lscparams.py ================================================

24 file(s) NOT LOADED

H1 CDS - Seismic activity bar added to top of CDS Overview MEDM

david.barker@ligo.org — Fri, 03 Oct 2025 09:52:10 -0700

Author: david.barker@ligo.org

Report ID: 87277

I have added a seismic activity bar, similar to the wind speed bar, to the upper right of the CDS Overview. Attached shows the bar during the current earthquake.

Similar to the wind speed, the bar fills from the left, start green then gets increasingly red.

This bar is logarithmic, each point is approximately a factor of about 2.5 from the last. The range is 1.0e+01 to 1.0e+05 BLRMS.

The bar is comprised of circles ("little earths") rather than squares.

Images attached to this report

H1 General - Lockloss @ 16:44 UTC - EQ

ryan.short@ligo.org — Fri, 03 Oct 2025 09:50:10 -0700

Author: ryan.short@ligo.org

Report ID: 87278

Lockloss @ 16:44 UTC after 12.5 hours locked - link to lockloss tool

M6.1 EQ out of Kamchatka followed by a M5.1 aftershock. I dropped observing at 16:26 UTC as it was coming in to engage the hi-gain ASC, which seemed to help for a while until the aftershock hit and peakmon reached about 2300 counts. Holding H1 in 'DOWN' until the ground settles.

Lockloss, SEI

H1 IOO - Comment to ISS measurements with new oscilloscope setting

jennifer.wright@ligo.org — Fri, 03 Oct 2025 09:27:20 -0700

Author: jennifer.wright@ligo.org

Report ID: 87275

We realised in the analysis that we should be using :

H_amp on QPD = Xcos theta + Y sin theta where theta is the angle between the X axis of the QPD and the horizontal scan direction of the beam worked out from our previous calibration measurments, 14 degrees.

This gives a different value for the couplings. All the PDs other than PD6 did not have coherences 0.9 or over so I only attach the final TF for PD6. We increased the dither amplitude after this to improve the measurement of the other PDs.

Images attached to this report

LHO General - Comment to Ops Day Shift Start

ryan.short@ligo.org — Fri, 03 Oct 2025 09:18:32 -0700

Author: ryan.short@ligo.org

Report ID: 87273

S251003at from this morning was retracted.

Also ran range comparison checks comparing this lock stretch to the last as our range is a bit better. Seems like DARM looks better overall above ~60Hz; Sheila says this is probably just because the squeezer is "better" today. Report attached.

Non-image files attached to this report

compare_darm_1443491030_1443524887.pdf

H1 SUS - Weekly In-Lock SUS Charge Measurement - FAMIS 28425

corey.gray@ligo.org — Fri, 03 Oct 2025 08:35:58 -0700

Author: corey.gray@ligo.org

Report ID: 87272

Had issues with FAMIS, so was not able to check this until today. Looks like the SUS Charge measurements ran this past Tuesday morning.

(A procedure note: when I ran the printing command, it would generate the ETMx plot, but that was it.....until I saved the plot to the desktop and then closed the generated .png plot. Then it would continue with the other plots (one at a time)---took me a bit to figure that out!)

Attached are the plots for all four Test Masses. Closing FAMIS 28425.

SUS

Images attached to this report

LHO General - Ops Day Shift Start

ryan.short@ligo.org — Fri, 03 Oct 2025 07:34:33 -0700

Author: ryan.short@ligo.org

Report ID: 87271

TITLE: 10/03 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 156Mpc
OUTGOING OPERATOR: Corey
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 3mph Gusts, 2mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.21 μm/s
QUICK SUMMARY: H1 has been locked for over 10 hours. S251003at earlier this morning at 13:23 UTC.

Wind low, microseism dropping
All other systems nominal

H1 General - Ops EVE Shift End

oli.patane@ligo.org — Thu, 02 Oct 2025 22:00:09 -0700

Author: oli.patane@ligo.org

Report ID: 87270

TITLE: 10/03 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 155Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY: Observing at 155 Mpc and have been locked for over 30 minutes. We recovered from the lockloss really quickly (59 minutes!) and I didn't need to intervene.
LOG:

23:30 UTC Observing and locked for almost 4 hours
01:59 GRB-Short E606552
03:22 Lockloss
04:21 NOMINAL_LOW_NOISE
04:24 Observing

H1 General - Comment to Lockloss

oli.patane@ligo.org — Thu, 02 Oct 2025 21:24:56 -0700

Author: oli.patane@ligo.org

Report ID: 87269

10/03/2025 04:24 UTC Back to Observing

H1 General - Lockloss

oli.patane@ligo.org — Thu, 02 Oct 2025 20:47:33 -0700

Author: oli.patane@ligo.org

Report ID: 87268

Lockloss at 2025-10-03 03:22 UTC after just over 7.5 hours locked. It looks like it was caused by a very sudden localish event between 0.3 - 3 Hz (0.3-3 Hz, 1-3 Hz CS).

picket fence, build-ups, LSC, QUADs, peakmon, CS movement vs LL

Lockloss

Images attached to this report

H1 General - Ops EVE Midshift Update

oli.patane@ligo.org — Thu, 02 Oct 2025 20:01:36 -0700

Author: oli.patane@ligo.org

Report ID: 87267

We are still Observing and have been Locked for over 7 hours now. Nothing to report.

H1 General - Ops EVE Shift Start

oli.patane@ligo.org — Thu, 02 Oct 2025 16:32:34 -0700

Author: oli.patane@ligo.org

Report ID: 87266

TITLE: 10/02 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 12mph Gusts, 6mph 3min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.29 μm/s
QUICK SUMMARY: Observing at 149 Mpc and have been Locked for almost 4 hours. Secondary microseism is going back down and wind is low.

LHO General - Ops Day Shift End

thomas.shaffer@ligo.org — Thu, 02 Oct 2025 16:30:32 -0700

Author: thomas.shaffer@ligo.org

Report ID: 87258

TITLE: 10/02 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY: Locked for almost 4 hours. Both relocks today needed an initial alignment, and took their time to lock DRMI, but eventually got there. No calibration measurement was run today due to the lock losses around commissioning time. We will need to get one on Saturday.
LOG:

1520 Reached low noise, but we are starting commissioning
1800 Lock loss
1944 Observing
2015 GRB short E606487

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
22:52	LASER	LVEA IS LASER HAZARD	LVEA	YES	LVEA IS LASER HAZARD \u0d26\u0d4d\u0d26\u0d3f(\u239a_\u239a)	13:52
14:53	FAC	Randy	Xarm	n	Xarm BTE inspections	18:53
14:53	PEM	Robert	LVEA	YES	Setup measurements	16:27
17:42	FAC	Kim	MX	n	Tech clean	18:42
19:38	Cheeta	Camilla	Opt Lab	n	Optics dropoff	19:52
19:39	FAC	Randy	Xarm	n	BTE inspection, near MX	21:52
20:29	FAC	Tyler	Mids	n	Checking on and signs	21:14
21:09	ISS	Keita, Jennie	Opt Lab	LOCAL	ISS array work	00:09
21:19	PCAL	Dripta	PCAL Lab	LOCAL	Taking pictures	21:28

H1 SUS - Comment to Sat Amps Modified: PR2 and SR2

oli.patane@ligo.org — Thu, 02 Oct 2025 15:26:27 -0700

Author: oli.patane@ligo.org

Report ID: 87264

(Since Jeff is out of town, I'm putting these in for these swaps.)

Here's the characterization data and fit results for S1000295, assigned to SR2 M3's ULLLURLR OSEMs.

This sat amp is a UK 4CH sat amp, D0900900 / D0901284.

The data was taken per methods described in T080062-v3, using the diagrammatic setup shown on PAGE 1 of the Measurement Diagrams from LHO:86807.

The data was processed and fit using
    ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/
         plotresponse_S1000295_SR2_M3_ULLLURLR_20250924.m

Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are
Optic    Stage    Serial_Number    Channel_Number     OSEM_Name    Zero_Pole_Hz    R_TIA_kOhm    Foton_Design
SR2      M3       S1000295         CH1                UL           0.0964:5.27    121.75    "zpk([5.27],[0.0964],1,""n"")"
                                   CH2                LL           0.0954:5.21    121.625    "zpk([5.21],[0.0954],1,""n"")"
                                   CH3                UR           0.0955:5.22    121.375    "zpk([5.22],[0.0955],1,""n"")"
                                   CH4                LR           0.0964:5.26    122    "zpk([5.26],[0.0964],1,""n"")"
                                   
  
The attached plot and machine readable .txt file version of the above table are also found in
    ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Results/

Per usual, R_TIA_kOhm is not used in the compensation filter -- but after ruling out an adjustment in the zero frequency (by zeroing the phase residual at the lowest few frequency points), I nudged the transimpedance a bit to get the magnitude scale within the ~0.25%. shown in the attached results. Any scaling like this will be accounted for instead with the absolute calibration step, i.e. Side Quest 4 from G2501621, a la what was done for PR3 and SR3 top masses in LHO:86222 and LHO:84531 respectively.

Non-image files attached to this report

2025-09-24_UKSatAmp_S1000295_D0901284-v5.pdf

H1 SUS - Comment to Sat Amps Modified: PR2 and SR2

oli.patane@ligo.org — Thu, 02 Oct 2025 15:24:07 -0700

Author: oli.patane@ligo.org

Report ID: 87263

(Since Jeff is out of town, I'm putting these in for these swaps.)

Here's the characterization data and fit results for S1100070, assigned to SR2 M2's ULLLURLR OSEMs.

This sat amp is a UK 4CH sat amp, D0900900 / D0901284.

The data was taken per methods described in T080062-v3, using the diagrammatic setup shown on PAGE 1 of the Measurement Diagrams from LHO:86807.

The data was processed and fit using
    ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/
         plotresponse_S1100070_SR2_M2_ULLLURLR_20250924.m

Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are
Optic    Stage    Serial_Number    Channel_Number     OSEM_Name    Zero_Pole_Hz    R_TIA_kOhm    Foton_Design
SR2      M2       S1100070         CH1                UL           0.0961:5.24    120.25    "zpk([5.24],[0.0961],1,""n"")"
                                   CH2                LL           0.0965:5.27    120.375    "zpk([5.27],[0.0965],1,""n"")"
                                   CH3                UR           0.0961:5.23    120.5    "zpk([5.23],[0.0961],1,""n"")"
                                   CH4                LR           0.0963:5.26    120.75    "zpk([5.26],[0.0963],1,""n"")"
                                   
  
The attached plot and machine readable .txt file version of the above table are also found in
    ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Results/

Per usual, R_TIA_kOhm is not used in the compensation filter -- but after ruling out an adjustment in the zero frequency (by zeroing the phase residual at the lowest few frequency points), I nudged the transimpedance a bit to get the magnitude scale within the ~0.25%. shown in the attached results. Any scaling like this will be accounted for instead with the absolute calibration step, i.e. Side Quest 4 from G2501621, a la what was done for PR3 and SR3 top masses in LHO:86222 and LHO:84531 respectively.

Non-image files attached to this report

2025-09-24_UKSatAmp_S1100070_D0901284-v5.pdf

H1 SUS - Comment to Sat Amps Modified: PR2 and SR2

oli.patane@ligo.org — Thu, 02 Oct 2025 15:21:18 -0700

Author: oli.patane@ligo.org

Report ID: 87237

(Since Jeff is out of town, I'm putting these in for these swaps.)

Here's the characterization data and fit results for S1100159, assigned to PR2 M2's ULLLURLR OSEMs.

This sat amp is a UK 4CH sat amp, D0900900 / D0901284.

The data was taken per methods described in T080062-v3, using the diagrammatic setup shown on PAGE 1 of the Measurement Diagrams from LHO:86807.

The data was processed and fit using
    ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/
         plotresponse_S1100159_PR2_M2_ULLLURLR_20250924.m

Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are
Optic    Stage    Serial_Number    Channel_Number     OSEM_Name    Zero_Pole_Hz    R_TIA_kOhm    Foton_Design
PR2      M2       S1100159         CH1                UL           0.0956:5.22      120.25    "zpk([5.22],[0.0956],1,""n"")"
                                   CH2                LL           0.0967:5.28      120       "zpk([5.28],[0.0967],1,""n"")"
                                   CH3                UR           0.0978:5.34      120       "zpk([5.34],[0.0978],1,""n"")"
                                   CH4                LR           0.0969:5.3       120       "zpk([5.3],[0.0969],1,""n"")"
                                   
  
The attached plot and machine readable .txt file version of the above table are also found in
    ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Results/

Per usual, R_TIA_kOhm is not used in the compensation filter -- but after ruling out an adjustment in the zero frequency (by zeroing the phase residual at the lowest few frequency points), I nudged the transimpedance a bit to get the magnitude scale within the ~0.25%. shown in the attached results. Any scaling like this will be accounted for instead with the absolute calibration step, i.e. Side Quest 4 from G2501621, a la what was done for PR3 and SR3 top masses in LHO:86222 and LHO:84531 respectively.

Non-image files attached to this report

2025-09-24_UKSatAmp_S1100159_D0901284-v5.pdf

H1 SUS - Comment to Sat Amps Modified: PR2 and SR2

oli.patane@ligo.org — Thu, 02 Oct 2025 15:19:25 -0700

Author: oli.patane@ligo.org

Report ID: 87262

(Since Jeff is out of town, I'm putting these in for these swaps.)

Here's the characterization data and fit results for S1100141, assigned to PR2 M3's ULLLURLR OSEMs.

This sat amp is a UK 4CH sat amp, D0900900 / D0901284.

The data was taken per methods described in T080062-v3, using the diagrammatic setup shown on PAGE 1 of the Measurement Diagrams from LHO:86807.

The data was processed and fit using
    ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Scripts/
         plotresponse_S1100141_PR2_M3_ULLLURLR_20250924.m

Explicitly, the fit to the whitening stage zero and pole, the transimpedance feedback resistor, and foton design string are
Optic    Stage    Serial_Number    Channel_Number     OSEM_Name    Zero_Pole_Hz    R_TIA_kOhm    Foton_Design
PR2      M3       S1100141         CH1                UL           0.0957:5.22    120.25    "zpk([5.22],[0.0957],1,""n"")"
                                   CH2                LL           0.0949:5.17    120.5    "zpk([5.17],[0.0949],1,""n"")"
                                   CH3                UR           0.0977:5.33    120.375    "zpk([5.33],[0.0977],1,""n"")"
                                   CH4                LR           0.0946:5.16    120.25    "zpk([5.16],[0.0946],1,""n"")"
                                   
  
The attached plot and machine readable .txt file version of the above table are also found in
    ${SusSVN}/trunk/electronicstesting/lho_electronics_testing/satamp/ECR_E2400330/Results/

Per usual, R_TIA_kOhm is not used in the compensation filter -- but after ruling out an adjustment in the zero frequency (by zeroing the phase residual at the lowest few frequency points), I nudged the transimpedance a bit to get the magnitude scale within the ~0.25%. shown in the attached results. Any scaling like this will be accounted for instead with the absolute calibration step, i.e. Side Quest 4 from G2501621, a la what was done for PR3 and SR3 top masses in LHO:86222 and LHO:84531 respectively.

Non-image files attached to this report

2025-09-24_UKSatAmp_S1100141_D0901284-v5.pdf

H1 General - Ops Day Mid Shift Report

thomas.shaffer@ligo.org — Thu, 02 Oct 2025 12:46:00 -0700

Author: thomas.shaffer@ligo.org

Report ID: 87261

We lost lock during commissioning for unknown reasons at 1800UTC. Relocking required an initial alignment, and DRMI took 12 minutes to lock, but it got there and we are now Observing at 1944UTC.

H1 ISC - Camera spot calibration

elenna.capote@ligo.org — Thu, 02 Oct 2025 11:58:08 -0700

Author: elenna.capote@ligo.org

Report ID: 87260

Today I began calibrating the camera servo signals into spot positions. I ran the A2L script at the nominal camera spot positions. Then, I changed the camera offset and waited for the camera servo to converge. Then I remeasured the A2L gain. Using the a2l_lookup function in /opt/rtcds/userapps/release/isc/common/scripts/decoup/BeamPosition the A2L gain can be converted into a spot position in mm. This is a slow process so it will take time to get the conversions for all.

Camera offset

A2L gain

Conversion

ETMY Pitch

start: -230, end: -231

start: 5.62, end: 5.92

(-23.2 mm - -21.8 mm)/-1ct

= 1.4 mm/ct

ITMX Pitch

start: -230, end: -231

start: -0.45, end: -0.56

(6.46 mm - 5.96 mm)/-1ct

= -0.5 mm/ct

LHO VE - Thu CP1 Fill

david.barker@ligo.org — Thu, 02 Oct 2025 10:39:05 -0700

Author: david.barker@ligo.org

Report ID: 87259

Thu Oct 02 10:07:28 2025 INFO: Fill completed in 7min 24secs

Images attached to this report

H1 TCS - HWS Origin Crosses Updated on ITMs

camilla.compton@ligo.org — Thu, 02 Oct 2025 09:02:37 -0700

Author: camilla.compton@ligo.org

Report ID: 87257

Matt, Camilla

After TJ and Dave fixed the HWS Live GUI 87252, Matt and I checked on it and re-centered the origin crosses which are meant to mark the center of where the IFO beam is heating the ITM, before and after, sdf diff. We moved them both down but we hadn't updated them in a few years so this isn't too surprising.

Also attached is a HWS image of the test masses comparing getting to 60W in to 180s later, plot. As usual, ITMY looks clean and ITMX has it's known point absorbers. There is some edge effects on ITMX that should be ignored.

Images attached to this report

LHO General - Ops Day Shift Start

thomas.shaffer@ligo.org — Thu, 02 Oct 2025 07:34:33 -0700

Author: thomas.shaffer@ligo.org

Report ID: 87256

TITLE: 10/02 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Ibrahim
CURRENT ENVIRONMENT:
SEI_ENV state: USEISM
Wind: 12mph Gusts, 8mph 3min avg
Primary useism: 0.03 μm/s
Secondary useism: 0.41 μm/s
QUICK SUMMARY: Looks like we lost lock 2 hours ago. An initial alignment was done an hour ago, but DRMI is not catching despite high flashes.

Planned calibration and commissioning today, but we need to get back up first.

LHO General - Wed EVE Ops Summary

corey.gray@ligo.org — Wed, 01 Oct 2025 22:00:12 -0700

Author: corey.gray@ligo.org

Report ID: 87254

TITLE: 10/01 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
INCOMING OPERATOR: Ibrahim
SHIFT SUMMARY:

H1 has been locked over 18hrs with no issues this shift.

H1 ISC - ISC Histograms

anthony.sanchez@ligo.org — Wed, 01 Oct 2025 18:04:20 -0700

Author: anthony.sanchez@ligo.org

Report ID: 87255

I took some more histograms of our locking sequences today.
ALS
DRMI-BiWeekly
DRMI-Monthly
DRMI-Daily Average
Carm
Powerup
& NLN

Images attached to this report

Non-image files attached to this report

output.pdf

H1 General - Second month of longer locks after ETMX ESD bias increased

oli.patane@ligo.org — Wed, 01 Oct 2025 16:32:05 -0700

Author: oli.patane@ligo.org

Report ID: 87251

Checking in on our DARM lockloss status after the second month of having our higher bias. At the end of August I put some comparison plots in to show how the doubling of the bias had significantly decreased the number of locklosses we had, as well as also significantly decreasing the amount of those locklosses that were due to the DARM glitch(86678). I remade those plots again now that we've gone through September.

In my usual lockloss vs DARM lockloss plot, we see that we've actually had no locklosses due to the DARM glitch between September 3rd - September 30th, which is the longest we've gone in all of O4 without that lockloss cause!

The average lock length has gone down a bit compared to August (10.8 vs 13.3 hours), but that's still double the average lock length of February, March, June, and July (table, plot). The number of lockloses is still also much lower than the pre-ESD-doubling months.

Lockloss

Images attached to this report

LHO General - Wed EVE Ops Transition

corey.gray@ligo.org — Wed, 01 Oct 2025 16:27:21 -0700

Author: corey.gray@ligo.org

Report ID: 87253

TITLE: 10/01 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
SEI_ENV state: USEISM
Wind: 8mph Gusts, 5mph 3min avg
Primary useism: 0.04 μm/s
Secondary useism: 0.59 μm/s
QUICK SUMMARY:

H1's been locked 12.5+hrs, even with microseism a little higher than last night! Cloudy skies, light breezes and an Operator BBQ celebrating O4a & Detections operators were on-shift for.

LHO General - Ops Day Shift End

thomas.shaffer@ligo.org — Wed, 01 Oct 2025 16:20:39 -0700

Author: thomas.shaffer@ligo.org

Report ID: 87246

TITLE: 10/01 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY: Locked for 12 hours. The useism is staying constant, wind is staying low.
LOG:

1418 GRB short E606087
1431 GRB short E606088
2137 GRB short E606216

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
22:52	LASER	LVEA IS LASER HAZARD	LVEA	YES	LVEA IS LASER HAZARD \u0d26\u0d4d\u0d26\u0d3f(\u239a_\u239a)	13:52
15:53	FAC	Randy	X arm	n	X arm beam tube enclosure inspections	21:48
16:48	FAC	Kim	H2 build	n	Swifting	17:00
20:37	FAC	Tyler	Mids	n	Checks	21:37

H1 TCS - HWS live GUI fixed

thomas.shaffer@ligo.org — Wed, 01 Oct 2025 16:19:13 -0700

Author: thomas.shaffer@ligo.org

Report ID: 87252

We recently noticed that the HWS live GUI wasn't working. In trying to troubleshoot this, I found that there are a few different instances of it - gitcommon area, userapps, personal alias's, and maybe others that I dont know about. They were either copies of the git code, pointed at different branches of the git repo, or modified versions, but none were consistent. I've now corrected the new path for the hws data directory (alog84865), and updated the git repo with the changes. The version in userapps I've just copied from this for now so it continues to work, but I'd like to change that in the future.

Long story short, it should work now.

H1 ISC - Comment to Measurements of IMC ASC DOFs coupling to RIN

matthewrichard.todd@ligo.org — Wed, 01 Oct 2025 13:27:14 -0700

Author: matthewrichard.todd@ligo.org

Report ID: 87250

I'm adding a plot of projections of the quiescent noise in each IMC DOF loop to the ISS second loop. Note, I've cut off the TFs above 3 Hz due to coherence loss.

Non-image files attached to this report

aligo_iss_noise_contributions.pdf

H1 General - Ops Day Mid Shift Report

thomas.shaffer@ligo.org — Wed, 01 Oct 2025 12:34:25 -0700

Author: thomas.shaffer@ligo.org

Report ID: 87249

Locked for 8.5 hours. The useism is still >90th percentile and our SEI_ENV node is in USEISM as a result. Range is stable.

H1 PSL - PSL 10-Day Trends

ryan.short@ligo.org — Wed, 01 Oct 2025 11:48:08 -0700

Author: ryan.short@ligo.org

Report ID: 87248

FAMIS 31105

Looks like most things have settled out after our table inspection last Tuesday (alog87143), although PMC reflected power has been moving around a bit more than usual. ISS diffracted power also has been falling slightly, but right now it looks to have settled at around our target of 4%.

Images attached to this report

H1 General - Comment to Automatic Injections Start Times Updated

ryan.short@ligo.org — Wed, 01 Oct 2025 11:38:13 -0700

Author: ryan.short@ligo.org

Report ID: 87247

I've put both Tuesday morning automatic injection start times back to their usual with magnetic injections starting at 7:20am and in-lock charge at 7:45am (both in local time). Guardians have been loaded.

OpsInfo

LHO VE - Comment to HAM6 Annulus Ion Pump (AIP) Replacement

gerardo.moreno@ligo.org — Wed, 01 Oct 2025 10:43:04 -0700

Author: gerardo.moreno@ligo.org

Report ID: 87245

(Jordan, TJ, Gerardo)

Late entry.

TJ powered ON the ion pumps over the weekend, that allowed for the pumps to reach very good vacuum pressure on the shared annuli system, then on Tuesday morning, Jordan isolated the annuli system for HAM5 and HAM6 from the mechanical pumps and turned off the aux carts.

A couple of hours later we removed the small can turbos, flex hoses and aux carts from the HAM5/6 area, to conclude the replacement of the HAM5 annulus ion pump body.

Images attached to this report

LHO VE - Wed CP1 Fill

david.barker@ligo.org — Wed, 01 Oct 2025 10:10:50 -0700

Author: david.barker@ligo.org

Report ID: 87244

Wed Oct 01 10:07:13 2025 INFO: Fill completed in 7min 9secs

Images attached to this report

H1 General - Locklosses from Observing

camilla.compton@ligo.org — Wed, 01 Oct 2025 09:09:37 -0700

Author: camilla.compton@ligo.org

Report ID: 87243

Looked at the last 6 locklosses from Observing.

Could see nothing much in all but one of them, 1443315128 where ETMX_L3 and DARM get noisy in the 70ms before LL, plot attached.

Lockloss

Images attached to this report

LHO General - Ops Day Shift Start

thomas.shaffer@ligo.org — Wed, 01 Oct 2025 07:34:18 -0700

Author: thomas.shaffer@ligo.org

Report ID: 87242

TITLE: 10/01 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
SEI_ENV state: SEISMON_ALERT_USEISM
Wind: 10mph Gusts, 7mph 3min avg
Primary useism: 0.04 μm/s
Secondary useism: 0.51 μm/s
QUICK SUMMARY: Locked for 3.5 hours. Two GRB shorts passed through, E606087 and E606088 at 1418 and1431UTC. No alarms. The useism is just getting above the 90 percentile.

Plans for today...Observe!