13:49:12 PDT power glitch. Lights flickered in OSB.
No UPS emails regarding this event. Attached CS mains mon trend shows issues with all 3 phases.
Closes FAMIS#37208, last checked 85791
HEPI pump trends looking as expected.
Continuing work from 86370, I was able to refit the MICH feedforward and get improvement.
The SRCL coupling doesn't seem to be dependent on the SRC ASC offsets that were implemented in this alog, as I checked the coupling today and it was the same as I measured last week (forgot to properly save references before closing DTT so you will just have to take my word for it for now). I was unable to get enough time to measure the high frequnecy SRCL coupling better and refit, so that remains a future task.
Broadband:
Start: 2025-08-18 18:53:06 UTC
Stop: 2025-08-18 18:58:16 UTC
Files:
/ligo/groups/cal/H1/measurements/PCALY2DARM_BB/PCALY2DARM_BB_20250818T175306Z.xml
Simulines:
Start: 2025-08-18 18:00:44.516123 UTC // GPS: 1439575262.516123
Stop: 2025-08-18 18:24:10.038319 UTC // GPS: 1439576668.038319
Files:
2025-08-18 18:24:09,876 | INFO | File written out to: /ligo/groups/cal/H1/measurements/DARMOLG_SS/DARMOLG_SS_20250818T180045Z.hdf5
2025-08-18 18:24:09,884 | INFO | File written out to: /ligo/groups/cal/H1/measurements/PCALY2DARM_SS/PCALY2DARM_SS_20250818T180045Z.hdf5
2025-08-18 18:24:09,889 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L1_SS/SUSETMX_L1_SS_20250818T180045Z.hdf5
2025-08-18 18:24:09,894 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L2_SS/SUSETMX_L2_SS_20250818T180045Z.hdf5
2025-08-18 18:24:09,900 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L3_SS/SUSETMX_L3_SS_20250818T180045Z.hdf5
Just adding some notes that this calibration measurement was taken with SRC ASC offsets, as detailed in this alog.
This report pulled a very old report for comparison, which is an error that Joe B is trying to work on fixing in the code. I regenerated the report so it could pull the most recent valid report, and the results are attached.
/ligo/home/camilla.compton/Documents/sqz/templates/dtt/20250819higher_order_modes.xml screenshot attached. Elenna opened POP beamdiv.| Type | Time (UTC) | Angle | DTT Ref | Notes |
| SQZ | 15:30:00 - 15:35:00 | (-)133 | ref 0 | |
| FDS Mid - SQZ | 15:37:00 - 15:39:00 | (-)111 | ref 1 | At 4dB ASQZ |
| FDS Mid SQZ, SRM YAW -1urad (offset -0.3) | 15:47:00 - 15:49:00 | (-)108 | ref 2 | Made better today and in 86363 |
| Mid SQZ, , SRM YAW -1urad, +8cts DHARD YAW | 15:51:30 - 15:53:30 | (-)108 | ref 3 | No change at 5 or 10kHz |
| Mid SQZ, , SRM YAW -1urad, CAM3Y -1count | 16:04:30 - 16:06:30 | (-)108 | ref 4 | Loop takes ~5 minutes to converge, buildups worse. No change at 5 or 10kHz. |
| Mid SQZ, , SRM YAW -1urad, CAM3Y +1count | 16:15:30 - 16:16:30 | (-)108 | not taken | Builds-ups same as normal. No change at 5 or 10kHz. |
| Mid SQZ, , SRM YAW -1urad, SRM PIT +2urad (offset +0.6) | 16:23:00 - 16:25:00 | (-)110 | ref 5 | Buildups worse, saw 5kHz was a little worse at 5kHz with +0.3 so went further. DHARD PIT started to grow at 1Hz. |
| Mid SQZ, , SRM YAW -1urad, SRM PIT -1urad (offset -0.3) | 16:27:00 - 16:29:00 | (-)107 | ref 6 | 5kHz better |
| Mid SQZ, SRM YAW -1urad, SRM PIT -2urad (offset -0.6) | 16:30:00 - 16:32:00 | (-)106 | ref 7 | 5kHz slightly worse |
| Mean SQZ | 16:35:00 - 16:37:00 | N/A | ref 8 |
camilla.compton/Documents/sqz/templates/dtt/20250818_SQZdata.xml and attached.| Type | Time (UTC) | SRCL Offset | Angle | DTT Ref |
| FIS SQZ | 16:42:30 - 16:45:30 | -382 | (-)124 | ref 1 |
| FIS SQZ | 16:48:30 - 16:51:30 | -200 | (-)153 | ref 2 |
| FIS SQZ | 16:58:30 - 17:01:30 | 0 | (-)224 | ref 3 |
| No SQZ | 17:02:30 - 17:05:30 | -382 | N/A | ref 0 |
Took above data at NLG of 16.0, checked and improved the NLG after data taken 76542.
| OPO Setpoint | Amplified Max | Amplified Min | UnAmp | Dark | NLG | Note |
| 80 | 0.108523 | 0.00199724 | 0.0067894 | -1.22e-5 | 16.0 | Without Optimizing Temp |
| 80 | 0.154115 | 0.00199724 | 22.7 | After Optimizing Temp |
I think we like these SRC ASC offsets, so I set up the guardian to keep them. While the overall effect is minimal, there was a small increase in the buildups that was repeatable: we switched these offsets on and off a few times as we were commissioning today and the buildups got slightly worse when they went off and slightly better when they went on. I tried to process the FIS data, and I think it shows that the overall change in the SRCL offset is minimal, but maybe someone else can confirm. Similarly, the calibration report show the fit of the sensing function is very good in the current model.
Now the guardian engages these SRC ASC offsets in the LOWNOISE_ASC state.
I have attached the results (plot one and plot two) from the FIS measurement, and the fit indicates that our current SRCL offset is fine (I think that's the correct interpretation here).
Here is a trend of the buildups and SRC ASC offsets (pitch and yaw are right on top of each other in the bottom plot). The plot shows that the buildups increase when we add these offsets and decrease when we disengage these offsets.
The calibration report is linked in this alog, and shows that the calibration model is still very good. (There are some strange errors in the report generation, but they are unrelated to this change).
Here is a more to-the-point executive summary of what these results today are indicating:
A large positive SRM pitch offset caused a growing 1 Hz oscillation in DHARD pitch as well. I'm not sure what to make of that yet, but I wanted to re-emphasize for future moves.
Since we are seeing an improvement in the buildups when adding SRM offsets, I think some of the prevalence of these modes could be related to some uncontrolled AS 72 offset which is changing the SRM alignment offset. We reran dark offsets when coming back from the vent, so the dark offset change on AS 72 could be effecting the SRM alignment in some way.
Mon Aug 18 10:06:54 2025 INFO: Fill completed in 6min 50secs
H1 ISI CPS Noise Spectra Check FAMIS 26545
HAM 5 Looks slightly quieter across most frequencies above 10Hz exceot 55 hz.
ETMY Looks like like it's seen an slight increase in motion around 85 Hz in both ST1 and ST2 when compairing to the last Famis Entry.
FAMIS 31099
Jason's FSS alignment in the enclosure last week (alog86315) is clearly seen on several trends. PMC transmitted power has also been getting lower seemingly due to the average ISS diffracted power making a few steps up over the past week; not sure if I have an explanation at this point for that. Next time the IFO is unlocked I can double-check the diffracted power and make sure it's staying at the desired 4.0%; right now it's a little high at 4.2%.
Weekly PSL Status report FAMIS 26548
Laser Status:
NPRO output power is 1.864W
AMP1 output power is 70.19W
AMP2 output power is 141.5W
NPRO watchdog is GREEN
AMP1 watchdog is GREEN
AMP2 watchdog is GREEN
PDWD watchdog is GREEN
PMC:
It has been locked 5 days, 23 hr 21 minutes
Reflected power = 23.79W
Transmitted power = 105.2W
PowerSum = 129.0W
FSS:
It has been locked for 1 days 18 hr and 55 min
TPD[V] = 0.8324V
ISS:
The diffracted power is around 4.4%
Last saturation event was 1 days 18 hours and 56 minutes ago
Possible Issues:
PMC reflected power is high
TITLE: 08/18 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 153Mpc
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 1mph Gusts, 0mph 3min avg
Primary useism: 0.01 μm/s
Secondary useism: 0.10 μm/s
QUICK SUMMARY:
15:36 UTC Dropped observing to start planned commissioning.
TITLE: 08/17 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 156Mpc
INCOMING OPERATOR: Oli
SHIFT SUMMARY:
Another nice evening (where I have yet to touch H1 for my 3rd shift in a row!) with H1 locked for just about 32hrs! And to top things off, we also had a GW candidate/superevent. PLUS, microseism continues to slowly drop and we there is virtually no wind!
LOG:
Recently, I looked into the narrow peaks in the 20-40 Hz region, noting that coherence with beam jitter sensors suggested that these peaks could be cleaned (86160) While the sharp jitter peaks may be cleanable (though we are having problems with this), many of the jitter peaks rest on pedestals that are not coherent with jitter or vibration sensors. See, for example, the peak at just above 20 Hz in the figure of the referenced log (here) - there is the sharp coherent peak and a broad pedestal that is not coherent with jitter sensors. During past periods when the sharp peak was not present, the pedestal was not present either. We subsequently found that this peak was produced by the Liebert AC in the warehouse building (86257), and the broad incoherent peak comes and goes with the coherent jitter peak as we turned the Liebert on and off (as Shivaraj noted).
To study the non-linear coupling producing these broad pedestals under the jitter peaks, I injected a slow frequency sweep using a global speaker injection so that I could viibrate all regions of the LVEA. The sweep reproduced the two types of coupling and showed that the coupling extended over a broad band, from at least 20 to 45 Hz.
To begin narrowing down the site of the broad non-linear coupling, I first injected using a shaker mounted on the PSL table. This produced a jitter peak without the pedestal, so the nonlinear part of the coupling is not at the PSL table.
I then shook the input beam tube because it was a dominant scatter site whose coupling we reduced in 2024 with baffle work and by adjusting the CP-Y compensation plate (76969). No coupling was noted for MC tube vibration levels that matched or exceeded the level induced in the MC tube by the speaker injection that produced the non-linear coupling. Therefor the non-linear coupling site is also not at the input arm MC tube.
The global acoustic, PSL table, and MC tube swept injections and the coupling to DARM are shown in the figure.
The next step is to continue this process in other regions of the LVEA to narrow down the coupling site.
TITLE: 08/17 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Observing at 159Mpc
INCOMING OPERATOR: Corey
SHIFT SUMMARY: We remained locked the entire shift, 25.5 hours.
LOG: No log.
15:53 UTC Red dust alarm in the optics lab, back to normal levels after 20 minutes. The wind has picked up in the past few hours.
TITLE: 08/17 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Observing at 157Mpc
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
SEI_ENV state: CALM
Wind: 11mph Gusts, 6mph 3min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.15 μm/s
QUICK SUMMARY:
H1's humming along at 25.5+hrs of lock. Environmentall, we are better with winds today and the microseism is slowly dipping and touching the 50th percentile.
Sun Aug 17 10:08:28 2025 INFO: Fill completed in 8min 25secs
Ivey, Edgard, and Brian have created new estimator fits (86233) and blend filters (86265) for the SR3 Y estimator, and we have new rate channels (86080), so we were excited to be able to take new estimator measurements (last time 85615).
Unfortunately, there were issues with installing the new filters, so I had to make do with the old filters: for the for the estimator filters, I used the fits from fits_H1SR3_2025-06-30.mat, and the blend filters are from Estimator_blend_doublenotch_SR3yaw.m, aka the DBL_notch filter and not the new skinny notch. These are the same filters used in the testing from 85615.
So the only difference between the last estimator test and this one is that the last test had the generic satamp compensation filters (85471), and this measurement has the more precise 'best possible' compensation filters (85746). Good for us to see how much of a difference the generic vs best possible compensation filters make.
Unfortunately, due to the filter installation issues as well as still trying to re set up the estimator channels following the channel name changes, I also didn't have much time to run the tests, resulting in the actual test with the estimator being only 5 minutes. Hopefully this is okay enough for at least a preliminary view of how it's working and then next week we can run a full test with the more recent filters. Like last time, the transition between the OSEM damping and the estimator damping was very smooth and the noise out of the estimator was visibly smaller than with the regular damping (ndscope1).
Measurement times
SR3 Y damp -0.1
2025-08-12 18:28:00 - 18:44:00 UTC
SR3 Y damp -0.1, OSEM damp -0.4
2025-08-12 18:46:46 - 19:03:41 UTC
SR3 Y damp -0.1, Estimator damp -0.4
2025-08-12 19:09:00 - 19:16:51 UTC
Attached below are plots of the OSEM yaw signal, the M3 yaw optical lever witness sensor signal, and the drive request from light damping, full damping (current setting), and estimator damping modes from Oli's recent estimator test.
The blue trace is the light damping mode, the red trace is the full damping mode, and the yellow trace is the estimator damping.
The first plot is of the OSEM signal. The spectrum is dominated by OSEM noise. The blue, light damping trace shows where the suspension resonances are (around 1, 2, and 3 Hz). Under estimator damping, the resonances don't show up as expected.
This second plot is of the OPLEV signal. It is much more obvious from this plot that the estimator is damping at the resonances as expected. Between the first and second, as well as the second and third peaks, the yellow trace of the estimator damping mode is below the red trace of the full damping mode. This is good because it is expected that the estimator damping is better than the current full damping mode between the peaks. There is some estimator noise between 3 and 4 Hz from the estimator. The light damping trace also sees a noticeable amount of excess noise between 10 to 15 Hz. We suspect this is due to ground motion from maintenance: third, fourth, and fifth plots show comparisons between ground motion in July (when the light damping trace was 'normal') and August. There is excess noise in X, Y, and Z in August when compared to July.
The sixth plot is of the drive requests. This data was pulled from a newly installed 512 samples/sec channel, while the previous analysis for a test in July (see: LHO: 85745) was done using a channel that was sampling at 16 samples/sec. The low frequency full damping drive request differs significantly between July and August, likely because aliasing effects caused the July data to be unreliable. Otherwise, the estimator is requesting less drive above 5 Hz as expected. We note that the estimator rolls off sharply above 10 Hz.
The last plot is of the theoretical drive requests overlaid onto the empirical drive requests. We see that the major features of the estimator drive request are accounted for, as expected.
Oli intends to install the filter and the new, clean fits (see LHO: 86366) next Tuesday to test the yaw estimator once more. Hopefully the installation is smooth!
I would like to clarify from my initial alog that when I said that "the only difference between the last estimator test and this one is that the last test had the generic satamp compensation filters", that was a lie!! The measurements taken for calibrating and figuring out the correct response drives were taken before the satellite amplifiers were swapped for SR3, so even just the OSEMINF calibration was not done with the new satellite amplifiers in mind, so the calibration we had in there at the time was not very accurate to what we had going on, so we can't really compare this measurement to the last one.