aLIGO LHO Logbook

H1 General - Comment to Ops Day Shift End

ibrahim.abouelfettouh@ligo.org — Mon, 25 Aug 2025 17:10:45 -0700

Author: ibrahim.abouelfettouh@ligo.org

Report ID: 86558

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
15:01	FAC	Nelly	MY	n	Tech clean	15:44
15:04	FAC	Kim	MX	n	Tech clean	16:10
16:44	FAC	Eric	EX	n	Checking out part that needs to be replaced	17:03
20:39		Camilla	OpticsLab	n	Sorting parts	21:17

H1 General - Ops Day Shift End

oli.patane@ligo.org — Mon, 25 Aug 2025 17:10:24 -0700

Author: oli.patane@ligo.org

Report ID: 86557

TITLE: 08/25 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 154Mpc
INCOMING OPERATOR: Ibrahim
SHIFT SUMMARY: Observing and have been Locked for over 14 hours now. This has been a very quiet shift. We had some commissioning earlier, and then had an earthquake coming in that was in the middle of the green earthquake zone so we decided to use the Hi ASC Gain button (first tested 86364). It turned out that the earthquake was so small that we didn't even need to go into Earthquake mode, but it was a good second test of this mode, and I found an import error in the script that was easy to fix but might have been bad if it had been found by someone facing an actual lockloss-causing earthquake.
LOG:

14:30 UTC Observing and have been Locked for over 4.5 hours
15:30 Out of Observing for Commissioning
18:36 Back into Observing
19:34 Hanford site monthly emergency testing phone call
22:42 Out of Observing due to earthquake coming in - we decided to test out the Hi ASC Gains script
22:53 Reverted back to NLN with the ASC Low Noise script
22:54 Back into Observing

H1 SUS - Correction/Update: SR3 Estimator Impact on ASC (plus new OMC and ASC-AS plots)

oli.patane@ligo.org — Mon, 25 Aug 2025 16:55:50 -0700

Author: oli.patane@ligo.org

Report ID: 86551

Jeff, Oli

On Thursday (86507) I alogged the differences we were seeing in the ASC with the SR3 estimator on. The time that I was taking as our 'reference time' for the estimator off, however, doesn't seem like it was a good time showing the lowest the ASC noise could be. You could say this caused us to over estimat(or) the differences.
So I plotted some more times with the estimator off, then with the estimator on, and I found that maybe the SR3 noise is limiting the ASC noise less than shown in 86507. However, I also found that below 0.2 Hz, where we thought that the estimators were elevating the noise, that also seems to have been not related to the estimator, so that is something we might not have to worry about.
Of course the peaks at 0.6 and 0.7 Hz are elevated in the estimator plots below due to not damping them in the inital blend filter (mentioned in 86507), and this is something that we partially fixed this morning (86544), and will be working on further damping at the next available commissioning time.

There are still times where the estimator on makes the noise better at some frequencies, but there are also other times where the estimator is on, but something else is limiting the noise, so it looks like SR3 isn't limiting the noise very much at all. It will still be interesting to see if adding estimators onto the rest of the SRC give us different results.

In the plots below, I am showing the variation in noise with the estimators off and the estimators on,
The 'bad' time for the estimators OFF is: 2025-08-17 09:00 UTC (green)
The 'good' time for the estimators OFF is: 2025-08-20 18:29 UTC (blue)
For the estimators ON times, they're both 'good' and 'bad' at different frequencies, so I'll just list their times:
2025-08-21 16:35 UTC (red)
2025-08-24 18:18 UTC (gold)

	Pitch			Yaw
ASC-DHARD	Error
	Est OFF	Est ON	Both	Est OFF	Est ON	Both
	Control
	Est OFF	Est ON	Both	Est OFF	Est ON	Both
ASC-MICH	Error
	Est OFF	Est ON	Both	Est OFF	Est ON	Both
	Control
	Est OFF	Est ON	Both	Est OFF	Est ON	Both
ASC-SRC1	Error
	Est OFF	Est ON	Both	Est OFF	Est ON	Both
	Control
	Est OFF	Est ON	Both	Est OFF	Est ON	Both
ASC-SRC2	Error
	Est OFF	Est ON	Both	Est OFF	Est ON	Both
	Control
	Est OFF	Est ON	Both	Est OFF	Est ON	Both
ASC-AS_A_DC	Control
ASC-AS_A_DC	Est OFF	Est ON	Both	Est OFF	Est ON	Both
ASC-AS_B_DC	Control
ASC-AS_B_DC	Est OFF	Est ON	Both	Est OFF	Est ON	Both
ASC-OMC_A	Control
ASC-OMC_A	Est OFF	Est ON	Both	Est OFF	Est ON	Both
ASC-OMC_B	Control
ASC-OMC_B	Est OFF	Est ON	Both	Est OFF	Est ON	Both

OMC-DCPD_SUM_OUT	Est Off	Est ON	Both
OMC-REFL_A_LF_OUT	Est Off	Est ON	Both

ISC, SEI

Images attached to this report

H1 ISC - new version of noise budget code: WIP

sheila.dwyer@ligo.org — Mon, 25 Aug 2025 16:32:37 -0700

Author: sheila.dwyer@ligo.org

Report ID: 86555

I've made a fresh start on the noise budget code, using much of the work and many of the functions from aligoNB, but in a code that should be overall simpler for us to work with. This exists in a repo here: simplenb.

Noises estimated using the excess power method can be read in either using gps times or from a dtt template. .xml files are tracked using git lfs and read in by dttxml. If a list of gps times is provided then the code will download the data using gwpy and save asds as a .pkl file, so that the data doesn't need to be downloaded each time the budget is run. Deleteing the pkl file from the local copy will cause it to redownload the data if the user wants to change times or resolution. The excess power projection is done using the frequency resolution of the dtt file, or right now it is hard coded to an fft length of 3 seconds for those made using a list of gps times. The noises are rebinned to a frequency vector specified for the budget after the projections are made.

Thermal noises are imported from gwinc. Quantum noises are also calculated using gwinc, which is why this code needs to be run in an environment that uses Kevin's superQK branch of gwinc. I've added a function save_quantum_params to my quantum noise modeling repo that takes a template of a yaml file including all the parameters you think are important for modeling quantum noise, and a ifo struct, which saves a yaml file with the current parameters. This function is also available in the quantum_utils.py function in this repo, so that people can use it with any method they like of generating a gwinc model of quantum noise to incorporate into this noise budget. I think it is best to leave the quantum noise budgeting separate from this repo for now, because the code for that is still evolving. For now I've used the quantum parameters where all the missing squeezing is explained by frequency dependent loss from 85942, the next step is to add mode mismatches to that model.

Running the budget.py script will generate noise budget plots, you can choose how many layers deep to go in plotting sub-budgets by setting that parameter in the make_all_plots function call in the final lines. The plots attached were made using the injections that Camilla made this morning (86550), and a reference time of 20:00 UTC.

Still to do:

Add missing noises:
- residual gas
- DAC noise
- PD dark noise
- Newtonian Noise
- remainder of ASC noises
Correct some noise terms:
- intensity noise has double counting around 1kHz (also an issue in old noise budget)
- frequency noise loop correction (it is measured with only one sensor in loop, in full lock we use 2 sensors)
Would be nice:
- specifiy the ftt length for excess power noises using gps times for each noise
- get Craig's interactive svg working, which isn't working in either model yet
- add some useful information to plot, like gps time of reference, maybe some quantum model parameters

Non-image files attached to this report

LHO General - OPS Eve Shift Start

ibrahim.abouelfettouh@ligo.org — Mon, 25 Aug 2025 16:14:10 -0700

Author: ibrahim.abouelfettouh@ligo.org

Report ID: 86556

TITLE: 08/25 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 13mph Gusts, 10mph 3min avg
    Primary useism: 0.11 μm/s
    Secondary useism: 0.09 μm/s
QUICK SUMMARY:

IFO is in NLN and OBSERVING as of 17:20 UTC (13.5 hrs!) (with some drops out of observing for various reasons).

Oli just finished testing Jim and Elenna's Earthquake robust ASC state during an earthquake, though we probably would have survived since it was a small EQ. I will turn this back on to continue testing if a sufficiently large EQ rolls in.

Otherwise, IFO is behaving excellently.

H1 SQZ - Comment to first look at sqz dataset, limit on IFO to OMC mode mismatch

sheila.dwyer@ligo.org — Mon, 25 Aug 2025 16:02:57 -0700

Author: sheila.dwyer@ligo.org

Report ID: 85942

Posting this comment which has been saved in my drafts, which I thought I'd posted a while ago:

I've taken a second quick look at this data, constructing a model in the same way that I've done in the past without any mode mismatches. This works OK, and suggests that for 347kW arm power we'd have 2.5% unknown readout losses and

This data can be fit reasonably well without frequency independent losses, no mode mismatch and an SRC detuning, simliar to previous data sets. This doesn't mean that there's not a mode mismatch, but there's not new evidence for mode mismatch here. Kevin did mention that I should look at scenarios where we have both SQZ to OMC mismatches and IFO to OMC mismatch. Indeed, when I do that the mismatch phase is important for the sqz and anti-sqz level at 2kHz.

Images attached to this report

H1 SUS - H1 SUS SR3 M1 Pitch and Yaw Estimator: Local Performance Metrics After Changing Pitch Blend Filter to -v2

jeffrey.kissel@ligo.org — Mon, 25 Aug 2025 15:43:28 -0700

Author: jeffrey.kissel@ligo.org

Report ID: 86553

J. Kissel, O. Patane, B. Lantz Continuing to refine my understanding of the metrics for the GS13 FF Estimator, I update the plots from LHO:86503. Also, I barely explained the plots there, so I'll try to do a better job here. First Point: Concepts and Clarification I've had a conceptual misunderstanding about what the estimator is at its core. Discussions with Brian have cleared this key point up for me: I had been calling the estimator a "GS13 Feed Forward Estimator," but that neglects a key innovation of the estimator. Not only does it use the HAM5 ISI GS13's to predict the susp-point motion input -- that's the feed-forward part -- but it also takes the total top mass *requested* drive from the suspension's M1 stage as well, and (with a 1 clock cycle delay) feeds that back as another input to the estimator. That's the composition of the estimator super sensor: the sum of the estimated input motion from the ISI as well as the total requested drive "including the estimator controls, what's left of the classic, broadband OSEM control, and any ISC drive". In the case of SR3, there is no AC ISC drive, just alignment offsets, so for the purposes of us looking at the ASDs as performance metrics it's irrelevant. So, saying that description of the total requested drive sentence again for SR3: "including the estimator controls [from GS13s and filtered estimated total drive] and what's left of the broadband OSEM control." Remember, for SR3, the original total EPICs gain on the OSEM-only damping loops was -0.5. So, "what's left of the OSEM-only damping loops" is -0.1 of the OSEM-only damping loops and whatever percentage of OSEMs is allowed to pass through the OSEM / Estimator Super-sensor blend on resonance. So -- what *are* the relevant local metrics? On the sensor side -- it's interesting (and necessary) to compare (a) the OSEM signal (b) the total Estimator Super Sensor, which is comprised of (c) the Estimated M1 motion caused by Suspension Point Motion, predicted by the HAM5 GS13s (d) the Estimated M1 motion caused by M1 drive, predicted by the internally *requested* M1 drive On the output drive side -- it's interesting (and necessary) to compare - the total internally requested drive; in the case of SR3 only from (1) the small, but broadband fraction of control from the OSEMs (2) when OFF, the larger broadband fraction of control from the OSEMs (3) when ON, the estimator control from . estimated M1 motion via GS13, . M1 drive, and . larger fraction of blend-filtered OSEM control The first two "TRACEKEY" attachments show these 4-trace "sensor" and 3-trace "drive" plots for pitch, with the estimator overview screen handy so you can relate the traces with where they are in the control system topology. Second Point: Pitch Sensors Alright, so let's look at the pitch plots. Open the "Pitch Sensor Metrics when P and Y Estimators are both ON" alone plot first. (i) As we already knew, the raw OSEM signal can't see anything. It's dominated by its sensor noise for the vast majority of the 0.05 to 50 Hz frequency band, with *some* real on-resonance motion peaking up above the noise at 0.64 Hz, 0.75 Hz, and 2.1 Hz. The 3.4 Hz mode isn't resolved at all. (ii) The estimator super sensor, however, does an awesome job at predicting the M1 motion at these resonances above the first 0.64 and 0.75 Hz pair; it's dramatically less that the OSEM sensor noise. The fits to the GS13 Sus. Point to M1 motion and M1 Drive to M1 motion are quite fruitful. In this f > 0.75 Hz region, you get an interesting mix of GS13 and M1 stage drive, alternating which is better. I'm a little surprised to see a 1.59 Hz mode estimated by the GS13s that isn't otherwise controlled at all, because it doesn't show up in the total M1 drive trace. (iii) Below 0.75 Hz -- the estimator seems to show that the M1 motion is completely dominated by suspension point motion. Is that real, or is that GS13 noise? Not so clear with these local metrics. The fact that ASC sees worse noise from 0.1 top 0.3 Hz with the estimator on (see LHO:86507 e.g. SRC2 Pitch Control signals), implies to me that it *is* GS13 noise, and we should still high-pass at least the pitch damping loop controller. OK. Now that you're used to the noise budget, turn on the comparison of these traces between P & Y estimators ON vs. OFF. (i) For the OSEMs, all the can see is the following: the estimators have made the on-resonance motion *worse* between 0.64 and 0.75, and at 2.1 Hz. But -- the OSEMs are still in-loop sensors, so some factors of 1 / (1+G) - like factors may be in play, confusing us as to whether this an artifact of their being less on-resonance loop suppression ... or something. We've gotta math that out still. (Again, the out-of-loop ASC error/control signals shown in LHO:86507 seem to indicate that there is more real on resonance motion, and the OSEMs are faithfully telling us the *change*. The on-resonance story, especially for pitch is going to continue to be "complicated" for a while. (ii) Comparison between the bright red vs. bright blue estimated super sensor really shows where we win pitch noise improvement with the P and Y estimators: between resonances in the frequency band between 0.75 and 8 Hz. Since we're using a factor of 5 less OSEMs (aside from on-resonance), the total M1 stage drive motion from the broadband OSEM damping loop drops by factors of 10x. (iii) Interestingly, the GS13s still predict suspension point motion to dominate below 0.75 Hz regardless of whether the estimators are on, but the M1 drive signal (unfortunately very subdominant) drops by a factor of 2x ish between 0.1 and 0.3 Hz at the microseism -- and it's by the same ratio of raw-OSEM noise to estimator super sensor / GS13 suspension point prediction. *That* says to me that we *are* doing better with the estimators ON at the useism, vs. what the ASC sensors are saying... Third Point: Pitch Drive Now let's switch to the M1 stage drive breakdown for pitch. Here, the comparison is a bit tough to grok immediately, because - With the estimators OFF, you're damping the SUS with -0.5 worth of OSEM broadband damping, but it's split through two paths -- the "classic" broadband path with 0.1 gain, and a "fader" broadband path with gain of -0.4, and summed (thanks linear algebra!). - With the estimators ON, the -0.1 gain "classic" path remains, for the other path the OSEMs are now blended to only have -0.4 gain on resonance. That explains the drive comparison plot then: (i) The off-resonance, total requested, M1 drive -- with the estimators ON -- drops as shown in the sensor plot, but does not drop entirely to the noise floor of the GS13 sus. point estimate because -- above 0.75 Hz and off-resonance the stage 1 motion is still limited by the -0.1 gain broadband OSEM path (which doesn't change from ON vs. OFF). (ii) The on-resonance story especially at and in-between the 0.64 and 0.75 Hz resonances, remains "interesting" / confusing. There's *more* drive from -0.1 gain OSEM path on resonance with the estimators on vs. off, but difference between the -0.4 OSEM path and full-estimator path drive is better focused on the two resoances, dropping the total-total drive in-between. This is confirming that something in the OSEM sensor path incorrectly sensing the motion in between 0.64 and 0.75 Hz and the -v2 pitch blend filters -- which restore the use of the drive / GS13 FF super sensor for this tiny, in-between frequency band -- is doing the right thing. Fourth Point: Yaw Sensors Ok -- now on to yaw sensors. I attach both the P&Y Estimators ON alone as well as ON vs. OFF, but you're good enough at looking at these now and yaw is apparently a much more simple story, so let's just open the ON vs. OFF comparison. (i) The GS13 estimate of the suspension point motion is *much* less than in pitch. The OSEM's don't see anything at all. (ii) Above 0.5 Hz, you see off-resonance improvement in the super-sensor estimation of M1 motion by the factors of 4x-5x improvement you would expect from dropping from -0.5 gain (total) usage of the OSEMs to -0.1. (iii) This actually advocates for making the blend filter notches in yaw *even skinnier* than the improvement discussed in LHO:86265. (iv) I'm not sure this would help, but seeing the estimated suspension point motion peak back above the control noise at 30-40 Hz says to me that (if we can) we should improve the ST0/HEPI feed-forward to ST1 motion for HAM5. The hump is present even in the Estimator OFF drive trace, so it tells me that the physical motion of the M1 stage is smaller than M1 cage motion. So, we also should consider -- if we can't improve the 30-40 Hz ISI motion (likely), then we roll-off the yaw damping loop controller (definitely easier, we should have plenty of phase margin). Fifth Point: Yaw Drive Finally -- the yaw drive. I'm not sure there's too much to discuss here, since the story is more simple and the same as what's seen in the sensors. With the estimator ON, you get the 4x-5x reduction in drive when you're not using the OSEM portion of the estimator. Summary Plot Once you're done thinking through it all, it's good to zoom back out and stare so I provide all the plots together -- see 2025-08-25_H1SUSSR3_M1_GS13FFEstimator_LocalPerformance_Summary_QuadPlot.png.SEI

Images attached to this report

H1 SUS - Measurement results for SR3 and PR3 Health check transfer functions with 20% P or Y gains

oli.patane@ligo.org — Mon, 25 Aug 2025 15:09:35 -0700

Author: oli.patane@ligo.org

Report ID: 86554

Over the past couple of weeks, I took transfer functions for SR3 and PR3 with different configurations of P or Y damping gain for the estimator, so here are the results for those plus a comparison of their peak locations.

SR3
DAMP P gain at -0.1 (nominally -0.5), other dof gains at their nominal -0.5
Measurements: 86203
Results: /ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/SR3/SAGM1/Results/2025-08-05_1800_H1SUSSR3_M1_ALL_TFs.pdf r12611

DAMP Y gain at -0.1 (nominally -0.5), other dof gains at their nominal -0.5
Measurements: 86202
Results: /ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/SR3/SAGM1/Results/2025-08-05_1700_H1SUSSR3_M1_ALL_TFs.pdf r12612

PR3
DAMP P gain at -0.2 (nominally -1.0), other dof gains at their nominal -0.2
Measurements: 86459
Results: /ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/PR3/SAGM1/Results/2025-08-19_1815_H1SUSPR3_M1_ALL_TFs.pdf r12613

DAMP Y gain at -0.2 (nominally -1.0), other dof gains at their nominal -0.2
Measurements: 86459
Results: /ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/PR3/SAGM1/Results/2025-08-19_1715_H1SUSPR3_M1_ALL_TFs.pdf r12614

Comparison between SR3 and PR3
Results:
/ligo/svncommon/SusSVN/sus/trunk/HLTS/Common/Data/allhltss_2025-08-25_SR3vsPR3Comparison_DampPat20percent_ALL_TFs.pdf r12615
/ligo/svncommon/SusSVN/sus/trunk/HLTS/Common/Data/allhltss_2025-08-25_SR3vsPR3Comparison_DampYat20percent_ALL_TFs.pdf r12614

Non-image files attached to this report

2025-08-05_1800_H1SUSSR3_M1_ALL_TFs.pdf

2025-08-05_1700_H1SUSSR3_M1_ALL_TFs.pdf

2025-08-19_1815_H1SUSPR3_M1_ALL_TFs.pdf

2025-08-19_1715_H1SUSPR3_M1_ALL_TFs.pdf

allhltss_2025-08-25_SR3vsPR3Comparison_DampPat20percent_ALL_TFs.pdf

allhltss_2025-08-25_SR3vsPR3Comparison_DampYat20percent_ALL_TFs.pdf

H1 ISC - Comment to ASC and LSC noise buget injections taken

jeffrey.kissel@ligo.org — Mon, 25 Aug 2025 13:33:57 -0700

Author: jeffrey.kissel@ligo.org

Report ID: 86552

FYI -- for the record, these noise budget excitations were taken *after* the SR3 pitch estimator's blend filters were updated to -v2 this morning (LHO:85544). (I sincerely doubt they'll play a role, but just stating for the record.)SUS

H1 ISC - ASC and LSC noise buget injections taken

camilla.compton@ligo.org — Mon, 25 Aug 2025 11:48:50 -0700

Author: camilla.compton@ligo.org

Report ID: 86550

Sheila, Camilla

Followed instructions in 74681, I did not go to NLN_CAL_MEAS but that would have given clearer signals. Last done in June 85250, . Saved in /ligo/gitcommon/NoiseBudget/simplenb/dtt_files/ but not yet pushed to git: https://git.ligo.org/NoiseBudget/simplenb. Note different folder location and git directory used.

CHARD_{P,Y}_EXC.xml
DHARD_{P,Y}_EXC.xml
MICH_{P,Y}_EXC.xml
MICH_excitation.xml (large peak around 25Hz)
SRCL_excitation.xml (was in NLN_CAL_MEAS)
PRCL_excitation.xml (was in NLN_CAL_MEAS)

Images attached to this report

H1 ISC - A2L script ran, is decoupling well

sheila.dwyer@ligo.org — Mon, 25 Aug 2025 10:26:26 -0700

Author: sheila.dwyer@ligo.org

Report ID: 86545

It has been a while since we ran our A2l decoupling script, so I ran it this morning. I also took before and after tranfer funstion measurements for the HARD loops to DARM, the script did improve things overall. The templates used for these measuerments are in userapps/asc/h1/templates/CHARD and DHARD. I've loaded these changes into ISC lock. I had planned to check if it is possible to do better than the script by adjusting ITMs in common and differential by hand, but based on these measurements that doesn't seem worth doing, as the only one close to DARM around 20 Hz is CAHRD P where the decoupling looks quite good at 20 Hz

Optic	DOF	Initial	Final	Diff
ETMX	P	3.18	3.07	-0.11
ETMX	Y	4.89	4.79	-0.1
ETMY	P	5.53	5.54	0.01
ETMY	Y	1.33	1.42	0.09
ITMX	P	-0.53	-0.45	0.08
ITMX	Y	3.25	3.16	-0.09
ITMY	P	0.08	0.19	0.11
ITMY	Y	-2.82	-2.75	0.07

Images attached to this report

H1 ISC - Comment to Elenna's new SRCL FF Fit turned on

camilla.compton@ligo.org — Mon, 25 Aug 2025 10:25:15 -0700

Author: camilla.compton@ligo.org

Report ID: 86549

I doubled the amplitude of the injection from 0.04 to 0.08, ran the template and saved as /lsc/h1/scripts/feedforward/SRCL_excitation.xml while FM5 was on, so that in the future we can try to fit a separate >100Hz filter as Elenna suggests in 86481. I didn't measure the pre-shaping as expect we recently have that.

Images attached to this report

H1 CAL - Comment to Procedural issues in LHO Calibration this week

joseph.betzwieser@ligo.org — Mon, 25 Aug 2025 10:18:23 -0700

Author: joseph.betzwieser@ligo.org

Report ID: 86547

So our understanding of what was wrong with the calibration around September 25th, 2024 00:00 UTC has improved significantly since then. We had 4 issues in total. 1) The above mentioned drivealign gain mismatch issue between model, h1calcs, the interferometer and GDS calibration pipeline. 2) The ETMX L1 stage rolloff change that was not in our model (see LHO alog 82804) 3) LHO was not applying the measured SRC detuning to the front end calibration pipeline - we started pushing it in February 2025 (see LHO alog 83088). 4) The fact that pydarm doesn't automatically hit the load filters button for newly updated filters means sometimes humans forget to push that button (see for example LHO alog 85974). Turns out that night the optical gain filter in the H1:CAL-DARM_ERR filter bank had not been updated. Oddly enough, the cavity pole frequency filter bank had been updated, but I'm guessing the individual load button was pressed In the filter archive (/opt/rtcds/lho/h1/chans/filter_archive/h1calcs/), specifically H1CALCS_1411242933.txt has an inverse optical gain filter of 2.9083e-07, which is the same value as the previous file's gain. However, the model optical gains did change (3438377 in the 20240330T211519Z report, and 3554208 in the bad report that was pushed, 20240919T153719Z). The epics for the kappa generation were updated, so we had a mismatch between the kappa_C value that was calculated, and to what optical gain it applied - similar to the actuation issue we had. It should have changed by a factor of 0.9674 (3554208/3438377). This resulted in the monitoring lines showing ~3.5% error at the 410.3 Hz line during this bad calibration period. It also explains why there's a mistmatch between monitoring lines and the correction TFs we provided that night at high frequency. Normally the ratio between PCAL and GDS is 1.0 at 410.3 Hz since the PCAL line itself is used to calculated kappa_C at that frequency and thus matches the sensing at that frequency to the line. See the grafana calibration monitoring line page. I've combined all this information to create an improved TF correction factor and uncertainty plot, as well as more normal calibration uncertainty budgets. So the "calibration_uncertainty_H1_1411261218.png" is a normal uncertainty budget plot, with a correction TF from the above fixes applied. The "calibration_uncertainty_H1_1411261218.txt" is the associated text file with the same data. "H1_uncertainty_systematic_correction.txt" is the TF correction factor that I applied, calculated with the above fixes. Lastly, "H1_uncertainty_systematic_correction_sensing_L1rolloff_drivealign.pdf", is the same style plot Vlad made earlier, again with the above fixes. I'll note the calibration uncertainty plot and text file was created on the LHO cluster, with /home/cal/conda/pydarm conda environment, using command: IFO=H1 INFLUX_USERNAME=lhocalib INFLUX_PASSWORD=calibrator CAL_ROOT=/home/cal/archive/H1/ CAL_DATA_ROOT=/home/cal/svncommon/aligocalibration/trunk/ python3 -m pydarm uncertainty 1411261218 -o ~/public_html/O4b/GW240925C00/ --scald-config ~cal/monitoring/scald_config.yml -s 1234 -c /home/joseph.betzwieser/H1_uncertainty_systematic_correction.txt I had to modify the code slightly to expand out the plotting range - it was much larger than the calibration group usually assumes. All these issues were fixed in the C01 version of the regenerated calibration frames.

Images attached to this report

Non-image files attached to this report

H1_uncertainty_systematic_correction.txt

H1_uncertainty_systematic_correction_sensing_L1rolloff_drivealign.pdf

calibration_uncertainty_H1_1411261218.txt

LHO VE - Mon CP1 Fill

david.barker@ligo.org — Mon, 25 Aug 2025 10:16:14 -0700

Author: david.barker@ligo.org

Report ID: 86548

Mon Aug 25 10:09:19 2025 INFO: Fill completed in 9min 16secs

Images attached to this report

H1 SQZ - SQZ Alignement checked after last weeks SRCL1 offset changes

camilla.compton@ligo.org — Mon, 25 Aug 2025 09:29:11 -0700

Author: camilla.compton@ligo.org

Report ID: 86546

Sheila, Camilla

We noticed that the high frequency SQZ was worse after the ASC SRCL1 Pit and YAW offset changes last week 86422, plot.

We ran the SQZ_OPO_LR 's SCAN_OPOTEMP, then SCAN_ALIGMENT_FDS (largest change was 8urad in ZM4 Y, plots here), then SCAN_SQZANG_FDS which brought the ADF error signal to zero which is great as means the ADF servo needs no adjustment. Altogether these three states brought the high frequency squeezing back to where it was a week ago, -4.3dB.

The ADF servo is very slow ~45minutes but this is preferred than it running away at the start of the lock.

Images attached to this report

H1 ISC - Elenna's new SRCL FF Fit turned on

camilla.compton@ligo.org — Mon, 25 Aug 2025 09:04:18 -0700

Author: camilla.compton@ligo.org

Report ID: 86543

In 86481, Elenna proposed using a new FF fit as the bruco showed SRCL coherence, this has improved the low frequency SRCL noise, but moved the bump at 200Hz to 100Hz, overal a small improvement, see plot attached. Saved in ISC_LOCK and safe and observe sdfs.

Images attached to this report

H1 SUS - SR3 P estimator blend filters updated

oli.patane@ligo.org — Mon, 25 Aug 2025 08:50:33 -0700

Author: oli.patane@ligo.org

Report ID: 86544

I have updated the blend filters used for the SR3 P estimator to add in the osem damping for the P peaks at 0.6 and 0.7. The filters I installed were the ones Brian made last Thursday, pit_v2. The filters were installed into the filter banks SUS-SR3_M1_EST_P_FUSION_MEAS_BP and SUS-SR3_M1_EST_P_FUSION_MODL_BP with the OSEM and model blend filters, respectively. They were placed in FM2, and I swapped over from FM1 to FM2 for both of them. These changes were updated in Observe and Safe sdf.

We turned the estimator on with these new filters at 2025-08-25 15:42UTC.

Images attached to this report

H1 General - Ops Day Shift Start

oli.patane@ligo.org — Mon, 25 Aug 2025 07:30:27 -0700

Author: oli.patane@ligo.org

Report ID: 86542

TITLE: 08/25 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 2mph Gusts, 1mph 3min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.09 μm/s
QUICK SUMMARY:

Observing at 151Mpc and have been Locked for over 4.5 hours. Commissioning today starting at 15:30UTC

X1 SEI - Measurement of reflectivity of SPI beamsplitters

richard.savage@ligo.org — Mon, 25 Aug 2025 06:36:30 -0700

Author: richard.savage@ligo.org

Report ID: 86541

DriptaB, TonyS, RickS

Responding to a request from Jeff Kissel, we modified the Pcal measurement setup and used the standard Pcal analysis scripts to measure the reflectivity of two types of beamsplitters that have been procured for the SPI upgrade: 50/50 and 85/15 beamsplitters (two of each). Usually we are interested in the ratios of the responsivities of the two power sensors, but the same measurement results can be combined differently to yield the beamsplitter ratio.

NOTE: The Pcal system wavelength is 1047 nm, not 1064 nm.

The boxes containing the optics were labeled:

SPI PWR BS, 1064nm

50R:50T 45 DEG-Ppos

Batch 16075HA1

and

SPI PWR BS, 1064nm

85R:15T 45 DEG-Ppos

Batch 16075HA1

We measured two of each of the two beamsplitter types (50/50 and 85/15).

The measurement results are shown in the plots attached below. Note that HOP stands for "hundredth of a percent."

The measured reflectivities are:

50R/50T #1, two measuremetns: R = 0.4830 ± 0.002 %; R = 0.4830 ± 0.002 %

50R/50T #2: R = 0.4827. ± 0.002%

85R/15T #1 two measurements: R = 0.8624 ± 0.0005%; R = 0.8625 ± 0.0005 %

85R/15T #2: R = 0. ± 0.8599 ± 0.0004 %

Given the small specified wedges in the beamsplitter substrates, the ghost beams from the AR surface would likely pass through the entrance apertures on the power sensors (one inch diameter) and add to the received power in both reflection and transmission. However, the AR surface reflectivty appeared to be below the specified 0.1 %. We were not able to identify and measure the power in the beams reflecting from the AR surface. We will have another look when we break down the measurement setup.

Measurement setup and details:

We increased the Pcal Optical Follower Servo offset to give about 600 mW in each of the two output beams. We blocked one of the output beams and used the other beam for the beamsplitter measurements.

We aligned the laser steering mirror inside the transmitter module such that this beam propagates parallel to the table surface and along a row of holes in the optical table.

We found that the Pcal module output beam had some stray light of unknown origin outside the main beam (mostly three spots - see photo below) so we installed an aperture upstream at the Tx module output to block this stray light.

We installed a Karl Lambrect TFPC-12-1047nm thin film polarizing beamsplitter cube and aligned it such that the plane of the cube is parallel to the optical table surface. The Pcal Tx module output beams are nominally polarized paralllel to the surface of the optical table, but we installed this BS cube and carefully aligned it's plane of incidence to ensure that the polarization would be parallel to the plane of incidence of the beamsplitter to be tested.

We then installed the beamsplitter to be tested in the transmitted (polarized parallel to the surface of the table) beam and aligned it such that the plane of incidence is parallel to the optical table surface and the reflected beam is parallel to a row of holes on the optical table (45 deg. AOI, p-pol) and centered on the entrance aperture of one of the Pcal integrating spheres. The power incident on the beamsplitter was measured to be 570 mW.

The beams transmitted by the beamsplitter to be tested was reflected by a Pcal HR mirror (Precision Photonics / ATFilms Y1S-1025-45, Lot# WO22401, ITM100509, Run# 213472) and aligned to propagate along a row of holes and be centered on the entrance aperture of the second Pcal integrating sphere. The fractional power transmission of this HR mirror was measured twice to be: 3.2e-4 and 3.9 e-4. Average = 3.6e-4. We correct for this loss of power in the transmitted beam in the BS reflectivity calculations.

SEI

Images attached to this report

Non-image files attached to this report

BS_refl_2025-08-19-12.pdf

BS_refl_2025-08-19-16.pdf

BS_refl_2025-08-20-15.pdf

BS_refl_2025-08-20-18.pdf

BS_refl_2025-08-21-11.pdf

BS_refl_2025-08-21-14.pdf

H1 General - Sunday Ops Eve Shift End

anthony.sanchez@ligo.org — Sun, 24 Aug 2025 22:05:23 -0700

Author: anthony.sanchez@ligo.org

Report ID: 86540

TITLE: 08/25 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 155Mpc
INCOMING OPERATOR: TJ
SHIFT SUMMARY:
H1 has been locked for 41+ hours
All systems still running well.
No events to report.

LOG:
No Log

H1 SEI - BSC & HAM CPS Spectra

anthony.sanchez@ligo.org — Sun, 24 Aug 2025 20:04:11 -0700

Author: anthony.sanchez@ligo.org

Report ID: 86539

H1 ISI CPS Sensor Noise Spectra Famis 26545

No obvious or alarming changes from the last CPS Sensor Noise Spectra.

Non-image files attached to this report

CPS_spectra_18:39-08_24_2025.pdf

H1 General - Sunday Ops Eve Shift Start

anthony.sanchez@ligo.org — Sun, 24 Aug 2025 16:36:56 -0700

Author: anthony.sanchez@ligo.org

Report ID: 86538

TITLE: 08/24 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 10mph Gusts, 4mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.09 μm/s
QUICK SUMMARY:
H1 has been locked for 35 hours and 45 min.
All systems appear to be running smoothly.

H1 General - Ops Day Shift End

oli.patane@ligo.org — Sun, 24 Aug 2025 16:32:52 -0700

Author: oli.patane@ligo.org

Report ID: 86537

TITLE: 08/24 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
INCOMING OPERATOR: Tony
SHIFT SUMMARY: Observing at 152 Mpc and have been Locked for almost 37 hours. Once again nothing at all happened during my shift
LOG:

no log

LHO VE - Sun CP1 Fill

david.barker@ligo.org — Sun, 24 Aug 2025 10:12:45 -0700

Author: david.barker@ligo.org

Report ID: 86536

Sun Aug 24 10:09:25 2025 INFO: Fill completed in 9min 21secs

Images attached to this report

H1 General - Comment to Ops Day Shift Start

oli.patane@ligo.org — Sun, 24 Aug 2025 07:46:46 -0700

Author: oli.patane@ligo.org

Report ID: 86535

Looks like there were a couple of GRB-Short alerts that came in early this morning (but no superevent candidates :( ):

2025-08-24 11:25 UTC GRB-Short E592892

2025-08-24 13:38 UTC GRB-Short E593158

H1 General - Ops Day Shift Start

oli.patane@ligo.org — Sun, 24 Aug 2025 07:38:34 -0700

Author: oli.patane@ligo.org

Report ID: 86534

TITLE: 08/24 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 150Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 2mph Gusts, 0mph 3min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.10 μm/s
QUICK SUMMARY:

Currently Observing at 150Mpc and have been Locked for almost 27 hours

H1 General - Saturday Night Ops shift End.

anthony.sanchez@ligo.org — Sat, 23 Aug 2025 22:00:59 -0700

Author: anthony.sanchez@ligo.org

Report ID: 86533

TITLE: 08/24 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
INCOMING OPERATOR: TJ
SHIFT SUMMARY:
H1 has been locked for 17+ hours.
All systems are still running smoothly.
No events to report.

LOG:
No Log

H1 General - Satuday Night Ops Shift

anthony.sanchez@ligo.org — Sat, 23 Aug 2025 17:00:46 -0700

Author: anthony.sanchez@ligo.org

Report ID: 86532

STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 14mph Gusts, 9mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.15 μm/s
QUICK SUMMARY:
H1 has been locked for 12 + Hours.
All systems seem to be running smoothly.
Secondardy useism looks to be falling & Wind forcasting is single digit wind speeds for the night, so it looks like a good night for Observing.

H1 General - Ops Day Shift End

oli.patane@ligo.org — Sat, 23 Aug 2025 16:30:48 -0700

Author: oli.patane@ligo.org

Report ID: 86531

TITLE: 08/23 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
INCOMING OPERATOR: Tony
SHIFT SUMMARY: We're Observing at 153 Mpc and have been Locked for almost 12 hours. Besides going out of Observing for the calibration measuremnts, I haven't had to do anything for the ifo. We had a GRB-Short alert come in at 20:11 UTC for E592892
LOG:

14:30 UTC Observing and have been Locked for almost 3 hours
18:30 Dropped Observing to run calibration
19:02 Back into Observing
20:11 GRB-Short E592892

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
17:09	EPO	Sam + tour	Overpass	n	Passing over	17:39

H1 CAL - Calibration Measurement August 23, 2025

oli.patane@ligo.org — Sat, 23 Aug 2025 12:09:11 -0700

Author: oli.patane@ligo.org

Report ID: 86530

Calibration suite run with IFO fully thermalized, having been Locked for over 6.5 hours.

calibration monitor screen

pydarm report 20250823T183838

Broadband
2025-08-23 18:31:57 - 18:37:08 UTC
/ligo/groups/cal/H1/measurements/PCALY2DARM_BB/PCALY2DARM_BB_20250823T183157Z.xml

Simulines
2025-08-23 18:38:37 - 19:01:56 UTC
/ligo/groups/cal/H1/measurements/DARMOLG_SS/DARMOLG_SS_20250823T183838Z.hdf5
/ligo/groups/cal/H1/measurements/PCALY2DARM_SS/PCALY2DARM_SS_20250823T183838Z.hdf5
/ligo/groups/cal/H1/measurements/SUSETMX_L1_SS/SUSETMX_L1_SS_20250823T183838Z.hdf5
/ligo/groups/cal/H1/measurements/SUSETMX_L2_SS/SUSETMX_L2_SS_20250823T183838Z.hdf5
/ligo/groups/cal/H1/measurements/SUSETMX_L3_SS/SUSETMX_L3_SS_20250823T183838Z.hdf5

Images attached to this report

Non-image files attached to this report

H1_calibration_report_20250823T183838Z.pdf

LHO VE - Sat CP1 Fill

david.barker@ligo.org — Sat, 23 Aug 2025 10:18:04 -0700

Author: david.barker@ligo.org

Report ID: 86529

Sat Aug 23 10:08:18 2025 INFO: Fill completed in 8min 14secs

Images attached to this report

H1 AOS - Ops Day Shift Start

oli.patane@ligo.org — Sat, 23 Aug 2025 07:35:50 -0700

Author: oli.patane@ligo.org

Report ID: 86528

TITLE: 08/23 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 150Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 4mph Gusts, 2mph 3min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.19 μm/s
QUICK SUMMARY:

Observing at 150Mpc and have been Locked for almost 3 hours

H1 General - Friday Night Ops Eve Shift

anthony.sanchez@ligo.org — Fri, 22 Aug 2025 22:22:00 -0700

Author: anthony.sanchez@ligo.org

Report ID: 86527

TITLE: 08/23 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 150Mpc
INCOMING OPERATOR: TJ
SHIFT SUMMARY:
H1 has been locked for 21+ Hours.

Dropped from observing during an earthquake but stayed locked.

Handful of small earthquakes and survived them.
Nothing else to report.

LOG:
No Log

H1 SQZ - Dropped from Observing due to SQZr unlock from 5.5 Mag EQ in Tonga.

anthony.sanchez@ligo.org — Fri, 22 Aug 2025 18:32:25 -0700

Author: anthony.sanchez@ligo.org

Report ID: 86526

At 00:42:03 UTC Verbals announced an incoming 5.5M Earthquake from Tonga.
At 00:56:16:UTC H1 dropped from Observing due to a SQZr Unlock that was very likely caused by the increased ground motion.
We went back to Observing at 01:01:39 UTC after the SQZ Man relocked itself.
I did put the OPS mode into earthquake for that moment.
At 01:02:10 UTC Earthquake mode was activated.

SEI

Images attached to this report

H1 General - Ops Eve shift for Friday Night

anthony.sanchez@ligo.org — Fri, 22 Aug 2025 16:46:20 -0700

Author: anthony.sanchez@ligo.org

Report ID: 86525

TITLE: 08/22 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 154Mpc
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 16mph Gusts, 9mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.19 μm/s
QUICK SUMMARY:

I inherited a 15+ hour lock from the day shift operator.
Everything looks like its running well.
Wind forcast looks great as well.

H1 General - Ops Day Shift End

oli.patane@ligo.org — Fri, 22 Aug 2025 16:30:46 -0700

Author: oli.patane@ligo.org

Report ID: 86524

TITLE: 08/22 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 154Mpc
INCOMING OPERATOR: Tony
SHIFT SUMMARY: Observing at 155Mpc and have been Locked for over 15 hours. Nothing happened during my shift at all.
LOG:

14:30 UTC Observing and have been Locked for 6.5 hours

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
15:37	FAC	Kim	OpticsLab	n	Tech clean	15:56
17:17	SPI	Jeff	OpticsLab	n	SPI Inventory	21:06

H1 AOS - Summary of SURF 2025 Project: Leo Schrader

leendert.schrader@ligo.org — Fri, 22 Aug 2025 14:05:41 -0700

Author: leendert.schrader@ligo.org

Report ID: 86521

Leo, Camilla, Jennie W.

Over the summer, a robust mode-matching simulation for the SQZ beam to the OMC was built using the a la mode library. This report serves to summarize the current state of the simulation and the relevant information one can extract from it.
Link to git code: https://git.ligo.org/leendert.schrader/alm-beam-simulation-for-sqz/-/tree/main SQZ_simulation_v4.m is currently the most recent version.

#1 A detailed description of the squeezed beam path.
Distances, curvature radii, incidence angles, refractive indices, etc. are all within the code file with comments on where they were obtained. This includes all information necessary to propagate the beam starting at the SQZ output (BM4), through ZM4-6, the OFI, SRM, and into the OMC.
These can also be found in the google doc in T2500228, though the curvature radii for ZM4/5 are not what are used in the simulation.

Related aLogs: 85282, 85339

#2 The beam characteristics between ZM5 and ZM6.
Using the beam profiling data from SQZT7 one can plot a "q manifold" which assigns a q parameter with respect to strain gauge values for ZM4 and ZM5.
That is, if one knows the strain gauge for ZM4/5, they can know the beam after ZM5.
Attached is a sample of the q manifold obtained by fitting the horizontal beam width data.

Related aLogs: 85917, 86365, 86519, 85775

#3 Simulated and experimental mode-matching at the OMC.
Simulated: By Propagating the q manifold forward to the OMC using the beam path constructed in a la mode, we can simulate mode-matching with respect to ZM4/5 strain gauge values. The simulation was found to be accurate for high mode-matching, but underestimates matching on the fringes of the strain gauge ranges (compared to collected data).
Experimental: Multiple OMC scans for mode-match were obtained, which allows us to characterize mode-matching across any strain gauge values for ZM4/5.

Attached is a picture of both the simulated and experimental matches against each other. The surface with a grid fits the experimental data, while the surface without grid is the simulated data.

Related aLogs: 86445, 86467, 86520

#4 ZM4 and ZM5 curvature estimates.
We estimate ZM4 curvature by interpolating data in E2100289. Note that preload was increased from 46 in lb to 75 in lb, hence why we had to "interpolate."
We predict the curvature of ZM4 acts as
R_ZM4 = 2/(-0.026296*V_ZM4 - 0.310465)
where V_ZM4 is the strain gauge value for ZM4.
This equation is achieved by assuming a linear voltage - to - optical power relationship (hence the '2 divided by a linear term'). The q manifold is then used to predict the ZM5 curvature values.
Therefore, by ranging the strain gauge in the simulation GUI, one can find simulated ranges for ZM4 and ZM5 curvature.
Note: ZM4 was selected for the above estimate, as we found it behaved "more linearly" than ZM5.

Miscellaneous: the simulation contains the unique SRM ray transfer matrix in the M_SRM variable (see the first interim progress report in T2500228 for details on computation).

For all reports and presentations related to the summer project, see the main DCC document T2500228.

SQZ

Images attached to this report

H1 General - Ops Day Midshift Status

oli.patane@ligo.org — Fri, 22 Aug 2025 14:01:29 -0700

Author: oli.patane@ligo.org

Report ID: 86522

We have now been Locked for almost 13 hours and have been in Observing since I got in this morning. Nothing to report.

H1 SQZ - Comment to PSAMS adjustments for SQZ-OMC mode matching

leendert.schrader@ligo.org — Fri, 22 Aug 2025 13:23:23 -0700

Author: leendert.schrader@ligo.org

Report ID: 86520

Leo, Jennie W., Camilla Below is a plot of the OMC scans fitted with a surface polynomial. The plot is from the presentation in T2500228, so the labels on axes will be different. This can be plotted on Matlab simply using the following code block (requires Curve Fitting Toolbox to use fit()). OMCX = [5.5, 4, 2.3, 3, 8.1, 2.3, 2.3, 6, 9.5, 6, 6, 9, 3, 8, 4, 9.5, 9.5]; OMCY = [-0.8, 0.34, 0.2, 0.85, -0.4, -0.1, 0.2, -0.4, -0.6, -4.5, -5.3, 2, 2, -2, -2, -5, -0.6]; OMCdata = [1-4.048/100, 1-3.412/100, 1-3.074/100, 1-3.234/100, 1-5.073/100, ... 1-3.176/100, 1-2.884/100, 1-2.174/100, 1-3.343/100, 1-9.490/100, 1-11.865/100, 1-6.282/100, 1-2.313/100, ... 1-3.013/100, 1-3.021/100, 1-9.179/100, 1-3.243/100]; omc = fit([transpose(OMCX), transpose(OMCY)], transpose(OMCdata), 'poly22'); p = plot(omc);

Images attached to this report

H1 AOS - Comment to SQZT7 Beam Profiling with different ZM4 and ZM5 PSAMS Settings

leendert.schrader@ligo.org — Fri, 22 Aug 2025 13:11:58 -0700

Author: leendert.schrader@ligo.org

Report ID: 86519

Leo, Jennie W., Camilla Attached is a plot of the q manifold from the q parameter data, which allows for characterizing the beam smoothly with respect to ZM4/5 strain gauge voltage values. The image is taken from the presentation uploaded to T2500228. The real plot will likely have slightly different labels to axes. Link to git code for plotting: https://git.ligo.org/leendert.schrader/alm-beam-simulation-for-sqz/-/tree/main

Images attached to this report

H1 SUS - Comment to Version 2 of a blend for the SR3 pitch estimator

brian.lantz@ligo.org — Fri, 22 Aug 2025 11:29:22 -0700

Author: brian.lantz@ligo.org

Report ID: 86518

Thanks Oli!

Also - as a note to myself - I've attached 1 sec of drive signal from the SR3 outputs at the time when both estimators were on (2025-08-21 16:40 UTC, see LHO log 86491 ). The pitch drive is about 30 to 50 counts pk-pk, and not particularly high frequency, compared to the 16384 model rate. This suggests that the low frequency DAC noise is worth following up, and also that it could theoretically be improved with whitening filters. However, since the DC levels are ~ 10k counts to hold the alignments, a simple gain probably wont work. plz note - I am NOT suggesting any changes here, just logging some observations for followup.

Images attached to this report

LHO VE - Fri CP1 Fill

david.barker@ligo.org — Fri, 22 Aug 2025 10:50:44 -0700

Author: david.barker@ligo.org

Report ID: 86517

Fri Aug 22 10:08:42 2025 INFO: Fill completed in 8min 38secs

Images attached to this report

H1 SUS - Comment to Version 2 of a blend for the SR3 pitch estimator

oli.patane@ligo.org — Fri, 22 Aug 2025 10:30:26 -0700

Author: oli.patane@ligo.org

Report ID: 86516

Updated make_SR3_Pitch_blend_v2.m to r12610 after fixing the filter name and the subblock it writes to. Will be loading these in the next time we lose lock.

H1 PSL - PSL Weekly Report FAMIS

oli.patane@ligo.org — Fri, 22 Aug 2025 08:10:17 -0700

Author: oli.patane@ligo.org

Report ID: 86515

Closes FAMIS#26550, last checked 86343

Laser Status:
    NPRO output power is 1.865W
    AMP1 output power is 69.91W
    AMP2 output power is 140.3W
    NPRO watchdog is GREEN
    AMP1 watchdog is GREEN
    AMP2 watchdog is GREEN
    PDWD watchdog is GREEN

PMC:
    It has been locked 9 days, 22 hr 41 minutes
    Reflected power = 23.7W
    Transmitted power = 105.3W
    PowerSum = 129.0W

FSS:
It has been locked for 0 days 7 hr and 57 min
TPD[V] = 0.8324V

ISS:
The diffracted power is around 4.0%
Last saturation event was 0 days 12 hours and 31 minutes ago

Possible Issues:
PMC reflected power is high

H1 General - Comment to Ops Day Shift Start

oli.patane@ligo.org — Fri, 22 Aug 2025 07:54:43 -0700

Author: oli.patane@ligo.org

Report ID: 86514

Our normal LVK teamspeak is back up, so I've moved us back over!

H1 General - Ops Day Shift Start

oli.patane@ligo.org — Fri, 22 Aug 2025 07:35:33 -0700

Author: oli.patane@ligo.org

Report ID: 86513

TITLE: 08/22 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 15mph Gusts, 10mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.19 μm/s
QUICK SUMMARY:

Observing at 153Mpc and have been Locked for 6.5 hours.

LHO General - Thurs EVE Ops Summary

corey.gray@ligo.org — Thu, 21 Aug 2025 22:02:27 -0700

Author: corey.gray@ligo.org

Report ID: 86508

TITLE: 08/22 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 149Mpc
INCOMING OPERATOR: TJ
SHIFT SUMMARY:

Uneventful shift up until a M7.5 EQ took over! Shift's almost over and I'm guessing we have another 45+min until we get out of LARGE_EQ mode. Will be switching over to automatic operations shortly and gave TJ a status text earlier tonight. Picket Fence continues to flash yellow.
LOG:

Tony noticed the Teamspeak server was down at the beginning of the shift and all other servers were down except virgo's--so we switched to using the virgo Teamspeak for the night.
00:09-00:15 shuttering shutters in the PCal Lab (tony)
01:04:58 - 01:05:00 Big glitch on H1 (but nothing out of the ordinary seen on other FOMs)
02:36 LOCKLOSS due to Big EQ

H1 AOS - Comment to M7.5 Earthquake from down near Argentina!

corey.gray@ligo.org — Thu, 21 Aug 2025 21:24:32 -0700

Author: corey.gray@ligo.org

Report ID: 86512

Just giving an update---It's been about almost 2hrs since the earthquake rolled thorugh (took down H1/L1/V1). Picket Fences has been flashing between yellow & red the last hour or so. Gave TJ (owl shift) a heads up. In the last 30min, EQ band has finally started finally slowly turning downward.

Additional Notes:

No Watchdogs were tripped for this EQ (it was originally posted as a M8.0, but then downgraded to M7.5)
02:28 Incoming EQ Alert on verbal
02:33 "EQ Mode" activated
02:36 LOCKLOSS
02:46 "Big EQ Mode" activated

H1 AOS - M7.5 Earthquake from down near Argentina!

corey.gray@ligo.org — Thu, 21 Aug 2025 20:18:23 -0700

Author: corey.gray@ligo.org

Report ID: 86511

H1's been down about 45min so far due to a M7.5 EQ....waiting for the earth to calm down, but the R-Waves are barely rolling through now.

H1 SUS - SR3 Estimator Impact on ASC

oli.patane@ligo.org — Thu, 21 Aug 2025 18:01:32 -0700

Author: oli.patane@ligo.org

Report ID: 86507

Jeff, Oli

Today we tested out the SR3 estimators for both Pitch and Yaw (86491). The ASC loops where we see a difference are DHARD, MICH, SRC1, and SRC2, since these all go through the SRC to their output ports. As expected, we don't see any effect on CHARD, PRC, or INP.

I've plotted comparisons of the ASC control and error signals during those times along with a reference time of earlier that morning.

The ultimate conclusion is that the SR3 P and Y estimators do work to make some of the ASC noise better, and the good thing is that in the places where we see that the estimator makes the noise worse, they all seem like easy improvements/fixes! The amount of improvement that we see doesn't look like much, but that's also expected since it's just SR3 that has the estimator out of the several suspensions in each ASC path. We expect that as we add more estimators along these paths, we will keep picking away at the suspension noise. We already see really impressive broadband improvement between 1-5 Hz on SRC1 and SRC2!

Main areas of concern:
    - For all ASC loops and both P and Y, we see heightened SR3 resonances on around 0.7 Hz when the SR3 P estimator is on. This is because the OSEM P blend filter was made without including the 0.7-0.8 Hz mode. That is being added in and that should solve that issue
    - Between 0.1 and 0.2 Hz for some loops, turning on the estimators puts in some extra noise from the GS13s, which aren't as sensitive at those lower frequencies. To solve this, we will be adding a high pass filter above those frequencies
    - A few peaks aren't being damped as well with the estimator as they were with normal damping; however, now that we've shown that the estimator decreases our noise(86455, 86503), we are hoping to be able to increase gain somewhere in the estimator system (possibly in SR3_M1_EST_Y_FUSION_MEAS_BP) to better damp our resonances while still seeing improvements in noise as compared to normal damping

Here are the times used to grab the traces:
Estimator ON for SR3 P and Y (RED) 2025-08-21 16:35:00 UTC
Estimator ON for SR3 Y (BLUE) 2025-08-21 15:34:06 UTC
Estimator ON for SR3 P (GREEN) 2025-08-21 16:05:00 UTC
Estimator OFF (PINK) 2025-08-21 10:27:00 UTC

ASC	Pitch	Pitch Notes/Comments (besides 0.7 Hz SR3 P estimator resonances)	Yaw	Yaw Notes/Comments (besides 0.7 Hz SR3 P estimator resonances)
DHARD	Error	0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON	Error	0.2-0.4 Hz - Transient noise with only Y Est ON? 0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON
DHARD	Control	0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON	Control	0.2-0.4 Hz - Transient noise with only Y Est ON? 0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON
MICH	Error	0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON 1.1 Hz - Every estimator ON configuration lowers noise	Error	0.1-0.2 Hz - Estimators ON elevates noise; need to high pass GS13 0.3-0.4 Hz - Transient noise with only Y Est ON?
MICH	Control	0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON 1.0 Hz - Y estimator ON alone adds some noise, but P estimator fixes it 1.1-1.5 Hz - Every estimator ON configuration lowers noise	Control	0.1-0.2 Hz - Estimators ON elevates noise; need to high pass GS13 0.3-0.4 Hz - Transient noise with only Y Est ON? 0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON
SRC1	Error	0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON 1.1 Hz - Every estimator ON configuration lowers noise	Error	0.15-0.4 Hz - Transient noise with only Y Est on? 0.6 Hz - Every estimator configuration lowers noise 0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON 1.0 Hz - Estimators ON elevate noise 1.2-3.1 Hz - Every estimator ON configuration lowers noise
SRC1	Control	0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON 1.1 Hz - Every estimator ON configuration lowers noise 3.0-10.0 Hz - P and Y estimator damping lowers noise; this is good but we don't know why it's doing that there	Control	0.25-0.4 Hz - Transient noise with only Y Est on? 0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON 1.0 Hz - Estimators ON elevate noise 1.2-3.0 Hz - Every estimator ON configuration lowers noise 3.0-10.0 Hz - Just P estimator ON gives us the best noise performance, and P and Y estimators ON gives us the worst noise performance. This is NOT good, and also doesn't match with what we see with the SRC1 P Control signals, so we don't know why it looks like this at all
SRC2	Error	0.1-0.2 Hz - Estimators ON elevates noise; need to high pass GS13 0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON 1.1-3.5 Hz - Every estimator ON configuration lowers noise	Error	0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON 1.0 Hz - Estimator ON elevates noise 1.1-2.1 Hz - Every estimator ON configuration lowers noise 2.1 Hz - Estimator ON elevates noise 2.5-5.0 Hz - Every estimator ON configuration lowers noise
SRC2	Control	0.1-0.2 Hz - Estimators ON elevates noise; need to high pass GS13 0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON 1.1-3.5 Hz - Every estimator ON configuration lowers noise	Control	0.6-0.8 Hz - SR3 P resonance elevated whenever P estimator is ON 1.0 Hz - Estimator ON elevates noise 1.1-2.1 Hz - Every estimator ON configuration lowers noise 2.1 Hz - Estimator ON elevates noise 2.5-5.0 Hz - Every estimator ON configuration lowers noise

ISC, SEI

Images attached to this report

H1 SUS - Version 2 of a blend for the SR3 pitch estimator

brian.lantz@ligo.org — Thu, 21 Aug 2025 17:22:22 -0700

Author: brian.lantz@ligo.org

Report ID: 86510

I created an updated blend for the SR3 pitch estimator. These are in the SUS SVN next to the first version. (see LHO log 84452)

The design script is blend_SR3_pitchv2.m

the Foton update script is make_SR3_Pitch_blend_v2.m

these are both in {SUS_SVN}/HLTS/Common/FilterDesign/Estimator/ - revision 12608

The update script will install the new blends into FM2 of SR3_M1_EST_P_FUSION_{MEAS/MODL}_BP with the name pit_v2. pit_v1 should still be in FM1. Turn on FM2, turn FM1 off.

Jeff and Oli tried the first one, and see that the first 2 modes (about 0.65 and 0.75 Hz) are seeing more motion with the estimator damping than the normal damping. To correct this, _v2 add OSEM signal to the estimator for those modes. See plots below - First 2 are the _v2 blend and a zoom of the _v2 blend. figure 3 shows the measured pitch plant vs. OSEM path - the modes line up pretty well. There is a bit of shift because the peaks are close together. I ~~expect~~ hope this will not matter. Figure 4 shows the plant vs. the model path. Now all 4 modes are driven by the measured OSEM signal instead of the model.

It is interesting to see that the model was not doing a good job of predicting the motion at the first 2 peaks. This is (I guess) because either (a) the model and the plant are different - or - (b) there are unmodeled drives pushing the plant (the suspension) that the model doesn't know about.

I'm guessing the answer is (b - unmodeled drives) and is likely from DAC noise. I think this because
1 - The plant fit is smooth and really good.
2 - In the yaw analysis that Edgard and Ivey are doing (not yet posted) the first mode of the yaw plant can be seen with the OSEM, but the ISI motion is much too small to excite that level of motion. But the OSEM can see motion, so something is exciting that motion.
3 - The DAC noise is the only thing I can think of.

Quick chat with Jeff indicates that the DAC noise models at those frequencies are not well trusted. We'll try something anyway and see if it is close. I don't see how to use the estimator to deal with that noise - we'd need to have an accurate realtime measurement.

SEI

Images attached to this report

Non-image files attached to this report

fig_pitchV2_SR3_blend_set.pdf

LHO General - LIGO Teamspeak Servers Appear To Be Down...In Meantime, Using Virgo Teamspeak Server

corey.gray@ligo.org — Thu, 21 Aug 2025 17:13:31 -0700

Author: corey.gray@ligo.org

Report ID: 86509

At the beginning of this shift, Tony noticed that we had errors for the LHO Control Room Teamspeak. He mentioned this to Jonathan, and they found out that all the LIGO/MIT Teamspeak servers are down and that we should use the Virgo server to maintain communications. So---You can find the "LHO Control Room" teamspeak account at:

server: teamspeak.ego-gw.it
room: EM Follow-up

Of course you can always phone the Control Room as well.

LHO General - Thurs EVE Ops Transition

corey.gray@ligo.org — Thu, 21 Aug 2025 17:02:58 -0700

Author: corey.gray@ligo.org

Report ID: 86505

TITLE: 08/21 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 150Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: SEISMON_ALERT
    Wind: 12mph Gusts, 6mph 3min avg
    Primary useism: 0.05 μm/s
    Secondary useism: 0.17 μm/s
QUICK SUMMARY:

H1's been locked 3.25+hrs. TJ passed on what he needed to do for relocking earlier (I've not had to lock H1 for any of my last 6-evening shifts in a row this week...we'll see how tonight goes for my last (7th EVE) shift of the week!). Environmentally, we had a small EQ from Japan roll through, winds are low, and µseism has slowly popped above the 50th percentile in the last 24hrs.

LHO General - Ops Day Shift End

thomas.shaffer@ligo.org — Thu, 21 Aug 2025 16:34:15 -0700

Author: thomas.shaffer@ligo.org

Report ID: 86490

TITLE: 08/21 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY: Locked for 3 hours. We had one lock loss during commissioning today, which had an automated relock. The SR3 OSEM esitmators are running now, but that is the only notable change to the IFO. There have been many trips out to the OSB vertex area to escort contractors, mark utilities, and search for a valve out in the hydrant area. Times in the log.
LOG:

1046 GRB Short E592190
1533 Comissioning start
1825 Lock loss
2014 Observing

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
15:01	SPI	Jeff	Opt Lab	n	Inventory	15:31
15:15	FAC	Kim	Opt Lab	n	Tech clean	15:38
15:52	VAC	Travis	MY	n	Craning and prepping for pump	17:50
16:22	FAC	Tyler, Watts	Vertex	n	Hydrant inspect and plan	17:25
16:28	FAC	Richard	Vertex	n	Metal detecting the shutoff valve	18:55
16:48	FAC	Kim	H2 build	n	Tech clean	17:13
17:25	FAC	Kim	MY	n	Tech clean	18:07
17:33	CAL	Rick, Tony	PCal Lab	Local	Measurements	18:34
17:41	CDS	Fil, Marc	MY	N	Parts delivery/pickup	18:18
19:41	FAC	Randy	MX	n	Equipment check	20:06
20:48	FAC	Tyler, contractor	vertex	n	Marking hydrant	21:14
21:55	FAC	Richard, Fil, Tyler	Vertex	n	Hydrant searchign	22:00
22:17	FAC	Tyler	FCES	n	Taking picutres outside the building (2223-2224UTC at building)	22:29

LHO VE - BSC1 Annulus Ion Pump

jordan.vanosky@ligo.org — Thu, 21 Aug 2025 16:33:24 -0700

Author: jordan.vanosky@ligo.org

Report ID: 86506

The annulus ion pump for BSC1 has railed again, this morning at ~3am PDT. There was no change in the internal pressure measured at PT120B (BSC2).

Gerardo and I had swapped the pump controller, see alog 85975, after it had railed previously.

We will continue to monitor and troubleshoot during the next Tuesday maintenance. Pump likely needs replacement.

Images attached to this report

H1 SUS - H1 SUS SR3 M1 Pitch and Yaw Estimator: Local Performance Metrics

jeffrey.kissel@ligo.org — Thu, 21 Aug 2025 15:41:13 -0700

Author: jeffrey.kissel@ligo.org

Report ID: 86503

J. Kissel, O. Patane We tested both the P and Y GS13 state-space estimator's sensor correction to the OSEM damping loops for the M1 stage of H1SUSSR3 this morning. See LHO:86491. Here're some of the local metrics showcasing the performance differences between "P and Y estimators OFF" and "P and Y estimators ON."ISC, SEI

Images attached to this report

H1 CDS - Comment to h1susex back up and running.

marc.pirello@ligo.org — Thu, 21 Aug 2025 15:38:59 -0700

Author: marc.pirello@ligo.org

Report ID: 86504

Everyone keeps asking so I figure it might as well be in the ALOG. Be aware, there is a big spider at EX, we think it is a big wolf spider. I estimate the size to be 5" or 13cm leg to leg. Its body seemed to be 3" length and 1" in diameter at its widest. Here are the pictures.

Images attached to this report

H1 CAL - Note on calibration immediately after re-locking for GPS 1422964623

joseph.betzwieser@ligo.org — Thu, 21 Aug 2025 13:52:36 -0700

Author: joseph.betzwieser@ligo.org

Report ID: 86502

This alog is intended as record keeping for a quick investigation into an out of observing mode data request for GPS time 1422964623 (Feb 7, 2025), when the LHO interferometer had just relocked, but calibration had not settled. Relevant monitoring lines and kappa value trend can be seen on the calibration LHO grafana page. I picked a period 15 minutes after the gps time as well settled (although Kappa_C was trending up with thermalization) to create an estimated calibration model closer to what I think should have been applied at the GPS time. I then took the ratio of that model's response function over the response function of the actually applied calibration model which was using the clearly frozen time dependent correction factors right after reaching low noise. The attached plot of that ratio shows the ratio has a maximum deviation in magnitude of about 12% and 8 degrees. I don't think this is exactly right, due to the clear trend in the kappa_C on the grafana page, but its close enough that I'd certainly be comfortable with a flat +/- 20%/20 degrees uncertainty statement.CAL

Images attached to this report

H1 General - Comment to Lock loss 1825UTC

thomas.shaffer@ligo.org — Thu, 21 Aug 2025 13:17:07 -0700

Author: thomas.shaffer@ligo.org

Report ID: 86501

Back to observing at 2014UTC. Automated relock that needed an initial alignment. We got the OK to run with the SR3 OSEM esitmators on, so I accepted those SDFs in Observing and Safe.

Images attached to this report

H1 General - Lock loss 1825UTC

thomas.shaffer@ligo.org — Thu, 21 Aug 2025 11:27:33 -0700

Author: thomas.shaffer@ligo.org

Report ID: 86500

Caused by comissioning activities.

H1 TCS - TCS Chiller Water Level Top-Off - Biweekly

thomas.shaffer@ligo.org — Thu, 21 Aug 2025 11:07:02 -0700

Author: thomas.shaffer@ligo.org

Report ID: 86499

FAMIS27822

No water added to either of the chillers, all filters looked good. There was no water in the leak detection Dixie cup, but there was a water stain at the bottom that I hadn't noticed before. Looks like it had been there a bit though since there was some dust within. I'll keep an eye on it.

H1 CAL - Calibration Sweep 1650UTC

thomas.shaffer@ligo.org — Thu, 21 Aug 2025 11:03:20 -0700

Author: thomas.shaffer@ligo.org

Report ID: 86493

Started the calibration 2hr 50min after power up, kappa C looked mostly leveled out by this point.

Simulines start:

PDT: 2025-08-21 09:56:40.367802 PDT
UTC: 2025-08-21 16:56:40.367802 UTC
GPS: 1439830618.367802

Simulines end:

PDT: 2025-08-21 10:19:54.348840 PDT
UTC: 2025-08-21 17:19:54.348840 UTC
GPS: 1439832012.348840

Files:

2025-08-21 17:19:54,197 | INFO | File written out to: /ligo/groups/cal/H1/measurements/DARMOLG_SS/DARMOLG_SS_20250821
T165641Z.hdf5
2025-08-21 17:19:54,204 | INFO | File written out to: /ligo/groups/cal/H1/measurements/PCALY2DARM_SS/PCALY2DARM_SS_20
250821T165641Z.hdf5
2025-08-21 17:19:54,209 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L1_SS/SUSETMX_L1_SS_20
250821T165641Z.hdf5
2025-08-21 17:19:54,213 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L2_SS/SUSETMX_L2_SS_20
250821T165641Z.hdf5
2025-08-21 17:19:54,218 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L3_SS/SUSETMX_L3_SS_20
250821T165641Z.hdf5

Images attached to this report

Non-image files attached to this report

H1_calibration_report_20250821T165641Z.pdf

H1 SUS - Comment to H1 SUS SR3 M1 Yaw Estimator Tested in Nominal Low Noise; Setup and Test Configurations

jeffrey.kissel@ligo.org — Thu, 21 Aug 2025 10:39:07 -0700

Author: jeffrey.kissel@ligo.org

Report ID: 86498

Also, the H1SUSSR3.txt filter file that includes all of this goodness is /opt/rtcds/lho/h1/chans/filter_archive/h1sussr3/H1SUSSR3_1439664560.txt which was auto-committed without message to the userapps repo location /opt/rtcds/userapps/release/sus/h1/filterfiles/H1SUSSR3.txt rev 32818 on 2025-08-20.

LHO VE - Thu CP1 Fill

david.barker@ligo.org — Thu, 21 Aug 2025 10:31:46 -0700

Author: david.barker@ligo.org

Report ID: 86497

Thu Aug 21 10:08:44 2025 INFO: Fill completed in 8min 41secs

Images attached to this report

H1 ISC - Comment to Attempt at measuring HO modes in OMC reflected port

jennifer.wright@ligo.org — Thu, 21 Aug 2025 10:29:53 -0700

Author: jennifer.wright@ligo.org

Report ID: 86496

Got the folder reference wrong for the xml file, its actually in /ligo/home/jennifer.wright/git/2025/DARM_OFFSET.

H1 CAL - Comment to Procedural issues in LHO Calibration this week

joseph.betzwieser@ligo.org — Thu, 21 Aug 2025 10:29:41 -0700

Author: joseph.betzwieser@ligo.org

Report ID: 86494

I am also posting the original correction transfer function (the blue dashed line in Vlad's comment's plot) here from Vlad for completeness. It was created by calculating the modeled response of the interferometer that we intended to use at the time (R_corrected), over the response of the interferometer that was running live at the time (R_original) corrected for online correction (i.e. time dependent correction factors such as Kappa_C, Kappa_TST, etc). So to correct, one would take the calibrated data stream at the time: bad_h(t) = R_original (t) * DARM_error(t) and correct it via: corrected_h(t) = R_original(t) * DARM_error(t) * R_corrected / R_original(t)

Non-image files attached to this report

H1_uncertainty_systematic_correction.txt

H1 SUS - H1 SUS SR3 M1 Pitch and Yaw Estimator Tested in Nominal Low Noise; Setup and Test Configurations

jeffrey.kissel@ligo.org — Thu, 21 Aug 2025 10:12:58 -0700

Author: jeffrey.kissel@ligo.org

Report ID: 86491

J. Kissel, O. Patane 2025-08-21 15:34 UTC Ramped over from using OSEM-only to using GS13 Y Estimator and "light" OSEM damping. 2025-08-21 16:05 UTC Turned OFF yaw estimator (back to ), turned ON P estimator. 2025-08-21 16:36 UTC Turned ON yaw estimator, P estimator remains ON. Woo! 2025-08-21 16:50 UTC Both estimators turned OFF (and immediately, calibration measurements start) - IFO reached nominal low noise at 14:10 UTC (so IFO is ~1.25 hours into thermalization, which we typically quote to be 3.0 hours "done" [not 1/e time constant]) - EQ band is low at 0.02 [um/s]_RMS (most recent EQ was 4.5 [hr] ago; 5.8 [mag] just north of Japan) - uSeism band is medium (for LHO summer) at 0.1 [um/s]_RMS - Wind is less than 5-10 [mph] 2025-07-01 These are in use are after the M1 OSEMs have had their satamps upgraded (LHO:85463, 2025-07-14 The upgraded satamp response was perfectly compensated with measured z:p's from testing in the EE lab LHO:85746) 2025-07-29 These are in use after the M1 OSEMs have had their absolute calibration improved (LHO:86070) After the above, HAM5 / SR3 estimator design was informed by the following measurements - 2025-07-29 (In the presence SR3 SUSPOINT Basis ISI EXC; (ISI GS13s projected to SR3 SUSPOINT Y) to (SR3 M1 DAMP Y) LHO:86075, - 2025-08-05 M1 to M1 LHO:86202, - 2025-08-05 (In the presence SR3 SUSPOINT Basis ISI EXC; (ISI GS13s projected to SR3 SUSPOINT P) to (SR3 M1 DAMP P) LHO:86203 - 2025-08-05 M1 to M1 LHO:86203 Design of estimator and blend filter aLOGs are quoted below by each filter 2025-08-19 Oli installed / configured these estimators this past Tuesday (LHO:86455) ::: PIT FILTERS ::: Design aLOG: LHO:86430 M1_EST_P_FUSION_MODL_SUSP_P_2GAP "ISI_fit" FM1 EPICS Gain: +1.0 sos(-0.001012906275385808, [-2.0001366554573741; 1.000136668010563; -1.999948594076947; 0.99994860612347214; -1.999955359352324; 0.99995565554604537; -1.999976011494571; 0.99997638571005953; -2.000046972353724; 1.0000477507088701; -1.9999816676161819; 0.99998231095588275; -1.999807905043806; 0.9998079477319114; -1.9999858561539881; 0.9999859195985662; -1.999989374293667; 0.99998949933234416; -1.9999885936664199; 0.99998867482680542; -1.9999967240112111; 0.99999852427171887; -1.9999908757192211; 0.99999261046439736]) "to_um/nm" FM2 zpk([],[],1.000000000000000,"n") %% Yes, this is a gain of 1.0 and thus is not doing anything. This is vestigial. Calibration has been absorbed into the "ISI_fit." M1_EST_P_FUSION_MODL_DRV_P_2GAP "M1_fit" FM1 EPICS Gain: +1.0 sos(6.9937614616314464e-08, [1.9999999999998279; 0.99999999999995282; -1.9999796747664531; 0.99998031671408905; -1.9999989658263551; 0.99999907355206619; -1.999984525961469; 0.99998458794634182; -1.999972378962787; 0.99997245232369414; -1.999986427026998; 0.99998650968797875; -1.9999982894453341; 0.99999986582789491; -1.9999908361882079; 0.99999257469114344]) "to_um/cts" FM2 zpk([],[],1.000000000000000,"n") %% Yes, this is a gain of 1.0 and thus is not doing anything. This is vestigial. Calibration has been absorbed into the "M1_fit." Design aLOG: LHO:86452 M1_EST_P_FUSION_MEAS_BP "pit_v1" FM1 EPICS Gain: +1.0 sos(0.1000427204344847, [-0.99977476062437198; 0; -0.99998082542398548; 0; -1.999507407187904; 0.99950802568624952; -1.9999459253790719; 0.99994656777201008; -1.9997448445054919; 0.99974638260765558; -1.9999542865584909; 0.99995602687005281]) M1_EST_P_FUSION_MODL_BP "pit_v1" FM1 EPICS Gain: +1.0 sos(0.8999572795655153, [-1; 0; -0.99998082542398548; 0; -1.999987516253469; 0.99998815869468505; -1.9999459253790719; 0.99994656777201008; -1.9999884578241209; 0.99999019525631272; -1.9999542865584909; 0.99995602687005281]) Copies of M1_DAMP_P: (EPICS Gain: -0.1) P_DAMP_OSEM EPICS Gain: -0.4 P_DAMP_FUSION EPICS Gain: -0.4 The filters ON in each of these damping loop controller filter banks rolloff_P soft roll-off of sensor noise zpk([0;2;5],[20;20;30;30],0.005,"n") boost_P extra gain at first Y resonance zpk([0.415914+i*0.587721;0.415914-i*0.587721;0.67;0.77],[0.246255+i*0.676579;0.246255-i*0.676579;0.131518+i*0.707886;0.131518-i*0.707886],1,"n") norm_P nominal unit conversion from um to ADC ct zpk([],[],43.478,"n") x0.628 gain adjustment from absolute calibration gain(0.628) bounceRoll highest V and R mode notch tailored for SR3 ellip("BandStop",4,1,60,27.5,28.0)ellip("BandStop",4,1,60,45.0,45.5)gain(1.25893) ellip_P aggressive roll-off of sensor noise zpk([0.64975+i*9.7463;0.64975-i*9.7463],[1.22183+i*5.87428;1.22183-i*5.87428;2.7978],1,"n") (total OSEM gain or OSEM+Estimator gain of -0.5 for P, the prior-to-estimator "nominal" gain we'd been running since Aug 15 2023 LHO:72249) ::: YAW FILTERS ::: Design aLOG: LHO:86233 M1_EST_Y_FUSION_MODL_SUSP_Y_2GAP "ISI_fit" FM1 EPICS Gain: +1.0 sos(-0.00097333255316384561, [-2; 0.99999999999999989; -1.999987505826812; 0.99998828408658169; -1.9999917387445989; 0.99999222786356268; -1.999991053658418; 0.99999120602937952; -1.9999951079581699; 0.99999667180704854; -1.9999907068801011; 0.99999239185345823]) "to_um/nm" FM2 zpk([],[],1.000000000000000,"n") %% Yes, this is a gain of 1.0 and thus is not doing anything. This is vestigial. Calibration has been absorbed into the "ISI_fit." M1_EST_Y_FUSION_MODL_DRV_Y_2GAP "M1_fit" FM1 EPICS Gain: +1.0 sos(1.1347068995497109e-08, [2.000000000001652; 0.99999999999677247; -1.9999881576357379; 0.99998893434766245; -1.999998372312229; 0.99999974909962519; -1.99998928164089; 0.99999097015263916; -1.999998867104356; 0.99999912434806359; -1.99999256126361; 0.99999271377731203]) "to_um/cts" FM2 zpk([],[],1.000000000000000,"n") %% Yes, this is a gain of 1.0 and thus is not doing anything. This is vestigial. Calibration has been absorbed into the "M1_fit." Design aLOG: LHO:86265 M1_EST_Y_FUSION_MEAS_BP "SKY_notch" FM1 EPICS Gain: +1.0 sos(0.000183409288171444, [1; 0; -0.99996165121563274; 0; -1.999942013670952; 0.99994237961280041; -1.999812801308257; 0.99981448778963355; -1.9999004183717279; 0.99990166730434937; -1.999852310365053; 0.99985308742131895; -1.9999736341441301; 0.99997367996470554; -1.9999216555380299; 0.99992180839221256]) M1_EST_Y_FUSION_MODL_BP "SKY_notch" FM1 EPICS Gain: +1.0 sos(0.9998165907118286, [-1.0000000000000011; 0; -0.99996165121563274; 0; -1.999961208202631; 0.99996289480915956; -1.999812801308257; 0.99981448778963355; -1.9999698386597631; 0.99997061576169488; -1.9998523103650541; 0.9998530874213194; -1.9999842083331081; 0.99998436119207135; -1.9999216555380299; 0.99992180839221256]) Copies of M1_DAMP_Y: (EPICS Gain: -0.1) Y_DAMP_OSEM EPICS Gain: -0.4 Y_DAMP_FUSION EPICS Gain: -0.4 rolloff_Y soft roll-off of sensor noise zpk([0;1],[20;30;30],0.01,"n") boost_Y extra gain at first Y resonance zpk([0.9;1.1],[0.173648+i*0.984808;0.173648-i*0.984808],1,"n") norm_Y nominal unit conversion from um to ADC ct zpk([],[],43.478,"n") x0.757 gain adjustment from absolute calibration gain(0.757) bounceRoll highest V and R mode notch tailored for SR3 ellip("BandStop",4,1,60,27.5,28.0)ellip("BandStop",4,1,60,45.0,45.5)gain(1.25893) ellip_Y aggressive roll-off of sensor noise zpk([0.97195+i*9.7195;0.97195-i*9.7195],[1.0264+i*4.9347;1.0264-i*4.9347;2.7978],1,"n") (total OSEM gain or OSEM+Estimator gain of -0.5 for Y, the prior-to-estimator "nominal" gain we'd been running since Aug 15 2023 LHO:72249)ISC, SEI

Images attached to this report

H1 SUS - Comment to SR3 SUSPOINT and OLTFs taken for estimator fit

oli.patane@ligo.org — Thu, 21 Aug 2025 10:08:33 -0700

Author: oli.patane@ligo.org

Report ID: 86495

The M1 to M1 TFs were supposed to be regular TFs so here is the alog for those: 86202

H1 CDS - VACSTAT: increased HAM1 delta-trip to reduce false positives on sensor glitches

david.barker@ligo.org — Thu, 21 Aug 2025 08:53:51 -0700

Author: david.barker@ligo.org

Report ID: 86492

Following Tuesday night's false positive alarm for HAM1 PT100_MOD2 due to a sensor glitch (alog 86472) this morning I increased the delta-trip values for this gauge from 1.0e-07 to 3.0e-07 Torr for all three lookbacks.

The Tuesday alarm was due to the delta-p glitching up to 2.0e-07, the slope channels only reached 50% of their trip values.

VACSTAT was restarted at 08:37 with these new values.

Images attached to this report

LHO General - Ops Day Shift Start

thomas.shaffer@ligo.org — Thu, 21 Aug 2025 07:33:45 -0700

Author: thomas.shaffer@ligo.org

Report ID: 86489

TITLE: 08/21 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 4mph Gusts, 1mph 3min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.13 μm/s
QUICK SUMMARY: Locked for 25 minutes after an earthquake knocked us out and it recovered all on its own. No alarms. Planned calibration and commissioning today, though with us being unthermalized at the start, we will need to rearrange a few items.

LHO General - Wed EVE Ops Summary

corey.gray@ligo.org — Wed, 20 Aug 2025 22:13:22 -0700

Author: corey.gray@ligo.org

Report ID: 86488

TITLE: 08/20 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 46Mpc
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY:

Smooth and uneventful shift with H1 locked entire shift and currently at 6.75hrs.
LOG: n/a

LHO General - Ops Day Shift End

thomas.shaffer@ligo.org — Wed, 20 Aug 2025 16:31:00 -0700

Author: thomas.shaffer@ligo.org

Report ID: 86476

TITLE: 08/20 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 151Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY: Locked for 1 hour after a fast lock loss (alog86483). Reacquisition was straight forward but I did need to run an initial alignment.
LOG:

1725-1742 Fire pump 1 on due to hydrant work
1745 HDF offsite
2055 Lock loss
2233 Observing

Start Time	System	Name	Location	Lazer_Haz	Task	Time End
15:54	FAC	Kim	Opt Lab	n	Tech clean	17:54
16:27	FAC	Tyler, HFD	Vertex	n	Hydrant fix	17:55
17:55	FAC	Kim	MX	n	Tech clean	18:33
18:35	ISC	Camilla	Opt Lab	n	Parts bin	19:26
20:03	FAC	Tyler	Vertex	n	Taking photos of the leaky hydrant	20:08
21:02	SPI	Jeff	Opt Lab	n	Inventory	21:17
21:05	SPI	Rick, Dripta, Tony	PCAL lab	yes	SPI BS meas.	22:41

LHO General - Wed EVE Ops Transition

corey.gray@ligo.org — Wed, 20 Aug 2025 16:28:32 -0700

Author: corey.gray@ligo.org

Report ID: 86487

TITLE: 08/20 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 150Mpc
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 14mph Gusts, 7mph 3min avg
    Primary useism: 0.03 μm/s
    Secondary useism: 0.10 μm/s
QUICK SUMMARY:

H1's been locked almost an hr (and TJ reported reacquisition was straightforward---good to know after yesterday's post-Maintenance locking issues!). Winds low, microseism is low (below 50th percentile' here's to smooth sailing!

H1 SQZ - Comment to PSAMS adjustments for SQZ-OMC mode matching

leendert.schrader@ligo.org — Wed, 20 Aug 2025 15:10:11 -0700

Author: leendert.schrader@ligo.org

Report ID: 86485

Following up on these OMC scans: attached is the table with all computed mode-mismatch values.

Non-image files attached to this report

Mode_mismatch_at_OMC.pdf

X1 SEI - Picomotor Science: Dimensions of Glenair MightMouse Connector

jeffrey.kissel@ligo.org — Wed, 20 Aug 2025 14:34:43 -0700

Author: jeffrey.kissel@ligo.org

Report ID: 86484

J. Kissel Dimensions of Glenair picomotor mightmouse connector for Science.

Images attached to this report

H1 General - Lock Loss 2055UTC

thomas.shaffer@ligo.org — Wed, 20 Aug 2025 14:11:23 -0700

Author: thomas.shaffer@ligo.org

Report ID: 86483

1439758519

No obvious cause, looks very fast.

H1 ISC - Recent measurements of ASC calibrations

elenna.capote@ligo.org — Wed, 20 Aug 2025 13:56:00 -0700

Author: elenna.capote@ligo.org

Report ID: 86482

Since the HAM1 vent, I have done a few different measurements of the ASC that provide information on how to calibrate WFS signals from counts to microradians. Here is a summary:

CHARD, INP1 and PRC2 results come from this alog

DHARD results come from this alog

SRM results come from this alog (if you are comparing values, I made a power normalization error in the linked alog)

BS results were taken but never alogged (shame on me)

All of these measurements were taken by notching all ASC loops at 8.125 Hz and injecting an 8.125 Hz line in the desired DoF. The osem wits provide the urad reference.

Unless otherwise specified, the witness channels are the bottom stage osems

DoF	Input Matrix	Calibration	Notes
CHARD P	-1 * REFL A 45 I + 0.6 * REFL B 45 I	0.0161 urad [ETMY L2] / ct [REFL A 45 I] 0.0109 urad [ETMY L2] / ct [REFL B 45 I]	measured as ETMY L2 wit, must transform to L3 urad, can also convert to cavity angle coherence near 1
CHARD Y	-1 * REFL A 45 I + 0.8 * REFL B 45 I	0.0113 urad [ETMY L2] / ct [REFL A 45 I] 0.00965 urad [ETMY L2] / ct [REFL B 45 I]	measured as ETMY L2 wit, must transform to L3 urad, can also convert to cavity angle coherence near 1
DHARD P	0.5 * AS A 45 Q - 0.5 * AS B 45 Q	0.00312 urad [ETMX L2] / ct [AS A 45 Q] 0.00312 urad [ETMX L2] / ct [AS B 45 Q]	measured as ETMX L2 wit, must transform to L3 urad, can also convert to cavity angle coherence = 0.8, 10 averages
DHARD Y	0.5 * AS A 45 Q - 0.5 * AS B 45 Q	0.00612 urad [ITMY L2] / ct [AS A 45 Q] 0.02 urad [ITMY L2] / ct [AS B 45 Q]	measured as ITMY L2 wit, must transform to L3 urad, can also convert to cavity angle coherence = 0.5, 10 averages
PRC2 P (PR2)	1 * POP X RF I	0.00033 urad / ct	coherence 1
PRC2 Y (PR2)	1 * POP X RF I	0.000648 urad / ct	coherence 1
INP1 P (IM4)	1.5 * REFL A 45 I + 1 * REFL B 45 I	0.0104 urad / ct [REFL A 45 I] 0.00988 urad / ct [REFL B 45 I]	coherence 1
INP1 Y (IM4)	2 * REFL A 45 I + 1 * REFL B 45 I	0.0141 urad/ct [REFL A 45 I] 0.00608 urad/ct [REFL B 45 I]	coherence 1
MICH P (BS)	1 * AS A 36 Q	0.0161 urad [M2]/ct	measured as BS M2 WIT/AS A 36 Q, must transform into M3 urad, coherence near 1
MICH Y (BS)	1 * AS A 36 Q		data not taken
SRC1 P (SRM)	1 * AS A 72 Q	16.9 urad/ct	coherence near 1
SRC1 Y (SRM)	1 * AS A 72 Q	10.6 urad/ct	coherence near 1

H1 ISC - More SRCL FF updates

elenna.capote@ligo.org — Wed, 20 Aug 2025 11:57:12 -0700

Author: elenna.capote@ligo.org

Report ID: 86481

Continuing my efforts to check and update the LSC coupling (see 86423 and 86370) I ran yet another bruco, which showed that now the dominant low frequency coherence is coming from SRCL.

In review, I have:

updated PRCL feedforward, which has greatly reduced the remaining coherence
updated MICH feedforward, again reducing coherence
and I did a minimal update to SRCL, which has not really done much (see linked SRCL coherence above)

I think we can do better. The main challenge is fitting the <100 Hz coupling while fitting the >100 Hz coupling, or at least not significantly worsening it. I think the fit would be easier if we made use of the parallel SRCLFF banks to fit a low and high frequency feedforward. This would require fitting the low frequency coupling, engaging it, and then remeasuring the high frequency coupling to fit separately.

I have what I think is a better fit to the low frequency coupling, currently saved in FM5 of the SRCLFF1 bank. To test this new filter:

take SRCL1FF gain to zero
turn off FM6 (current) and turn on FM5
ramp SRCL1FF gain back to 1
run SRCL injection template and compare with the reference (best practice would be getting a same day injection first on FM6 to compare with)
- use SRCL_excitation_20240824.xml saved in /opt/rtcds/userapps/release/lsc/h1/scripts/feedforward/
if the filter performs better, change the guardian code in LOWNOISE_LENGTH_CONTROL to use FM5 and update SDF

Time permitting, if the new filter works, taking a better measurementing of the coupling from 100 Hz and up while on the new filter would be a useful next step, which may require adjusting the excitation shape or increasing the excitation gain.

To motivate the use of commissioning time on this, I did a very simple coherence based subtraction of the SRCL noise to see what it could get us in range improvement. I used the same time as the bruco I linked above, so this time includes the PRCL and MICH improvements. I copied some of Oli's range compare code to help me generate this nice plot comparing 1 hour of strain with coherence subtraction of the SRCL noise. Even if we can't improve the feedforward above 100 Hz, there is possible a 2 Mpc improvement from below 100 Hz.

Non-image files attached to this report

SRCL_subtraction.pdf

H1 ISC - Comment to PRC1 returned to PRMI ASC

elenna.capote@ligo.org — Wed, 20 Aug 2025 11:13:57 -0700

Author: elenna.capote@ligo.org

Report ID: 86480

Rereading this, I realized that saying it "didn't work" is very vague.

More words:

I stepped around with the PRM slider, watching both the POP18 and POP90 buildups. While watching the buildups, I looked to see when various signals crossed zero. For PRM pitch, REFL A 9 I clearly had a good zero crossing at the maximized buildup. The difference was the sign flip, which I tested by turning on the loop and seeing the error signal go the wrong direction (away from zero), and then the right direction (towards zero) when the gain sign was flipped. To maintain the gain sign as set by the guardian, I flipped the sign on the input matrix value from positive (pre-vent value) to negative.

For PRM yaw, the REFL signals did not cross zero when the buildups were maximized. However, the POP X RF signal did cross zero. I also watched the POP QPDs, which are sensitive to PRM, but also require some offset. I decided setting some offset and trying to use the REFL WFS was probably a bad idea, so I chose POP X RF yaw as the error signal. I calibrated it by measuring the signal difference in counts compared to the sliders steps I took, which are in urad. I checked the overall sign using the similar loop engagement test I described above.

LHO VE - Wed CP1 Fill

david.barker@ligo.org — Wed, 20 Aug 2025 11:00:42 -0700

Author: david.barker@ligo.org

Report ID: 86479

Wed Aug 20 10:09:36 2025 INFO: Fill completed in 9min 32secs

Gerardo confirmed a good fill curbside.

Images attached to this report

LHO FMCS - Fire pump 1 turned on while in Observing 1725-1742UTC

thomas.shaffer@ligo.org — Wed, 20 Aug 2025 10:55:52 -0700

Author: thomas.shaffer@ligo.org

Report ID: 86478

While fixing a hydrant on the backside of the OSB/vertex area, fire pump 1 was activate from 1725-1742UTC. Hanford FD pickup truck and our F150 were also back in that area. Their driving to and from that area, as well as some of their work showed up on our ITMY seismometer.

DetChar

Images attached to this report

LHO General - Comment to Ops Day Shift Start

david.barker@ligo.org — Wed, 20 Aug 2025 10:35:39 -0700

Author: david.barker@ligo.org

Report ID: 86477

HFD are working on a hydrant, Tyler has requested the fire_pump alarms be bypassed for the next two hours.

Bypass will expire:
Wed Aug 20 12:31:32 PM PDT 2025
For channel(s):
H0:FMC-CS_FIRE_PUMP_1
H0:FMC-CS_FIRE_PUMP_2

H1 ISC - Comment to Problem with DHARD WFS, CARM offset reduction

elenna.capote@ligo.org — Wed, 20 Aug 2025 07:57:50 -0700

Author: elenna.capote@ligo.org

Report ID: 86475

Apologies for missing this detail in my original alog, but we had run two successful initial alignments. The first was run as usual after the end of the maintenance day. Green alignment converged properly, arm alignment looked good. We ran a second after the early problems with DHARD, thinking that maybe the alignment was poor. Same results, good green convergence, but problems with DHARD.

In general, the alignment of the arms and corners looked very good through this whole process. When I stepped in DHARD P and Y, I was making very small steps overall to correct the alignment, steps on the order of 0.01 or 0.03. In general, the buildups and the camera showed good alignment. The green arms also stayed well aligned when the DHARD signal engaged properly, which is telling me that our initial alignment was doing the correct thing for the ITMS. Is it possible that the CARM offset was too large? I have been wondering this, because if the alignment was decent but the WFS signal was junk because we were too far from resonance that might explain this behavior, and it lines up with the fact that the better fix was reducing the carm offset more before moving to REFL. I'm not sure if that makes sense though.

As a side note, DRMI was mostly locking very quickly throughout the night.

LHO General - Ops Day Shift Start

thomas.shaffer@ligo.org — Wed, 20 Aug 2025 07:33:33 -0700

Author: thomas.shaffer@ligo.org

Report ID: 86474

TITLE: 08/20 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 152Mpc
OUTGOING OPERATOR: Ryan S
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 3mph Gusts, 1mph 3min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.07 μm/s
QUICK SUMMARY: Locked for 11.5 hours, no alarms, calm environment. Looks like we dropped Observing at 1053-1057UTC because the SQZr lost lock and relocked.

Our range isn't as stable as it has been lately, and the Omicron glitch gram FOM shows some extra SNR around 20-30Hz during those times.