Follow up to Oli's measurements in [LHO: 87363 LHO: 87611].

We did the fitting for the SR3 OSEM estimator with the M1 drive measurements from today plus the Suspoint measurements from two weeks ago.

The plant is not nearly as reciprocal as the PR3 plant, I wonder what that means.

The fits had to be obtained by tweaking over the PR3 OSEM estimator model posted in [LHO: 87593]. This worked really fast, and produced very clean results. I think we might use this method as a way to retune the estimators in the future.

The .pdf attached has the image of the Estimator L/P models for bookkeeping.

The fits are contained in fits_H1SR3_LP-2025-10-07.mat have been uploaded to the SVN under revision 12740 to

(svnroot)/sus/trunk/HLTS/Common/FilterDesign/Estimator.

Here are the ZPKs for the model

_____________________________________________________________________________

SUSPOINT TO M1
 
Suspoint L to M1 L fit
zpk([0,0,-0.06-4.33i,-0.06+4.33i,-0.051-7.177i,-0.051+7.177i,-0.089-15.255i,-0.089+15.255i],[-0.073-4.136i,-0.073+4.136i,-0.07-4.666i,-0.07+4.666i,-0.071-9.92i,-0.071+9.92i,-0.155-18.168i,-0.155+18.168i],-0.001)
 
Suspoint L to M1 P fit
zpk([0,0,0.935-6.789i,0.935+6.789i,-1.049-6.865i,-1.049+6.865i,-1.085-18.474i,-1.085+18.474i,0.833-18.561i,0.833+18.561i],[-0.078-4.113i,-0.078+4.113i,-0.058-4.655i,-0.058+4.655i,-0.071-9.916i,-0.071+9.916i,-0.165-13.116i,-0.165+13.116i,-0.221-18.058i,-0.221+18.058i,-0.053-21.596i,-0.053+21.596i],0.383)
 
Suspoint P to M1 L fit
zpk([0,0,-0.103-4.364i,-0.103+4.364i,-0.095-9.007i,-0.095+9.007i,-0.071-17.115i,-0.071+17.115i],[-0.071-4.094i,-0.071+4.094i,-0.055-4.64i,-0.055+4.64i,-0.062-9.948i,-0.062+9.948i,-0.158-18.146i,-0.158+18.146i],0)
 
Suspoint P to M1 P fit
zpk([0,0,-0.002-4.162i,-0.002+4.162i,0.006-4.65i,0.006+4.65i,0.036-5.615i,0.036+5.615i,-0.011-9.179i,-0.011+9.179i,-0.065-9.837i,-0.065+9.837i,-0.052-14.212i,-0.052+14.212i,-0.017-21.873i,-0.017+21.873i],[-0.06-4.105i,-0.06+4.105i,-0.01-4.178i,-0.01+4.178i,-0.02-4.629i,-0.02+4.629i,-0.028-4.68i,-0.028+4.68i,-0.019-9.793i,-0.019+9.793i,-0.045-9.975i,-0.045+9.975i,-0.139-13.128i,-0.139+13.128i,-0.041-21.608i,-0.041+21.608i],-0.001)
 
 
M1 DRIVE TO M1
 
M1 drive L to M1 L fit
zpk([-0.067-4.297i,-0.067+4.297i,-0.003-5.174i,-0.003+5.174i,-0.024-12.283i,-0.024+12.283i],[-0.064-4.12i,-0.064+4.12i,-0.057-4.635i,-0.057+4.635i,-0.072-9.904i,-0.072+9.904i,-0.155-18.168i,-0.155+18.168i],0.136)
 
M1 drive L to M1 P fit
zpk([1.502-5.563i,1.502+5.563i,-1.589-5.824i,-1.589+5.824i,-14.284,14.718,1.462-17.431i,1.462+17.431i,-1.276-17.775i,-1.276+17.775i],[-0.068-4.121i,-0.068+4.121i,-0.063-4.638i,-0.063+4.638i,-0.072-9.905i,-0.072+9.905i,-0.158-13.118i,-0.158+13.118i,-0.163-18.132i,-0.163+18.132i,-0.056-21.582i,-0.056+21.582i],0.078)
 
M1 drive P to M1 L fit
zpk([1.399-5.266i,1.399+5.266i,-1.594-5.6i,-1.594+5.6i,2.034-16.482i,2.034+16.482i,-2.192-17.091i,-2.192+17.091i],[-0.073-4.113i,-0.073+4.113i,-0.06-4.63i,-0.06+4.63i,-0.068-9.924i,-0.068+9.924i,-0.163-13.118i,-0.163+13.118i,-0.143-18.158i,-0.143+18.158i,-0.072-21.583i,-0.072+21.583i],-25.295)
 
M1 drive P to M1 P fit
zpk([-0.075-4.398i,-0.075+4.398i,0-5.423i,0+5.423i,-0.068-9.979i,-0.068+9.979i,-0.002-20.622i,-0.002+20.622i],[-0.069-4.109i,-0.069+4.109i,-0.051-4.632i,-0.051+4.632i,-0.076-9.938i,-0.076+9.938i,-0.164-13.126i,-0.164+13.126i,-0.074-21.58i,-0.074+21.58i],76.066)
 

I needed to retake measurements for the SR3 M1 to M1 L estimator in the L and P degrees of freedom because the ones from 87363 didn't have good enough coherence.

Settings:
- ISI in ISOLATED
- SUS in ALIGNED
- Estimators off (using regular damping)
- L DAMP gain to 20% (-0.1), P DAMP gain at 20% (-0.1), Y DAMP gain to 100% (-0.5)

Results:
M1 to M1
/ligo/svncommon/SusSVN/sus/trunk/HLTS/H1/SR3/SAGM1/Data/2025-10-21_1600_H1SUSSR3_M1_WhiteNoise_EstL_{L,P}_0p02to50Hz.xml r12738

These have a lot better coherence now

Since it was installed, HAM7 ISI has been prone to trips if people are working nearby. Often walking by the chamber is enough, but work in the squeeze racks, HAM6 ISC racks or unplugging electronics from nearby outlets has caused CPS saturations. After talking to Jeff, we decided to try disconnecting HAM7 from the corner timing system and try running the ISI using it's own local 10khz timing clock signal. I pulled the P3 jumper from the H1 CPS and disconnected the timing DB9 that connects HAM7 to the timing system. Position readout seems unchanged before vs. after the change. This shouldn't affect anything else.

As I entered the VEA at X-End I noticed an out place noise, I tracked the noise source to be a noisy power supply at the vacuum rack.  Made the report to Filiberto and Richard, noise points to a fan issue.

Filed a FRS ticket, number 35689.

Tue Oct 21 10:08:56 2025 INFO: Fill completed in 8min 53secs

After my change to the laser power guardian (87545 87581) caused a problem last night (87598) , I edited it so that the power scaling is set to a function.  If the IMC is locked, it will use IMC-IM4_TRANS_NSUM_OUTMON , if not it will use H1:IMC-PWR_IN_OUT16.  

I also made a plot to check if the IMC throughput is dropping as we power up, it is dropping but only by 0.4%.  

Per FAMIS, VEA AHU fans were lubricated and swapped. Where AHU 2 previously operated both fans, and AHU 1 operated just 1 this has been flipped. AHU 1 is presently running both fans while AHU 2 runs just one. Ahead of this swap, the non-running fan in AHU 1 was SF1 (nearest the exterior wall).

E. Otterman T. Guidry

TITLE: 10/21 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Microseism
OUTGOING OPERATOR: TJ
CURRENT ENVIRONMENT:
    SEI_ENV state: USEISM
    Wind: 8mph Gusts, 5mph 3min avg
    Primary useism: 0.08 μm/s
    Secondary useism: 0.71 μm/s 
QUICK SUMMARY:

Detector was put in DOWN earlier due to very high secondary ground motion. Maintenance day is today.

Workstations were updated and rebooted.  This was both an OS packages update and a conda packages update.

In the CDS conda environment, the python package dttxml was updated to fix a bug, details here:  https://git.ligo.org/cds/software/dttxml/-/issues/17

Ryan S, Keita K, TJ S

After the lock loss at 0427 UTC (2027PT), Ryan S started an initial alignment. Green went as usual, but he couldn't get Xarm IR to go. I'll put more details below, but the issue was that the change I made earlier today to change the LASER_PWR guardian to use the IM4 trans channel (alog87581) upon Sheila's findings that gain scaling based on IMC REQUEST caused gain reductions after the power outage (alog87545), caused the power scaling to go to -1.4 after the lock loss. We reverted this change and will have to make it a bit smarter to use this channel in the future.

More details:

Ryan and I initially thought it was an odd alignment and chased that with the usual checking of suspension alignments, checking temperatures, etc. We just couldn't get any flashes to show up on LSC-TR_X_NORM_INMON. On the front FOM, POP90 was visible and noisy, both things that shouldn't be at this point of initial alignment. We eventually thought that maybe it was a dark offset issue since the TR_X channel wasn't quiet at 0, so we ran the dark offset script. This didn't help but I've attached the SDF screenshots. While looking at this channel more, Ryan noticed that it would dip below 0 frequently, almost as if it was flashing but into the negative values. Sign flip somehow? We tried to understand this for awhile and eventually gave up to call the top person on the call list, Keita.

While we were describing the issue to Keita and starting to look into where a sign flip could have happened, Ryan noticed that the power scaling was at -1.4. Since this should just scale with the IFO input power, it shouldn't ever be negative. I plugged in 2.0 and, then everything looked normal again. Looking at the last attachment, IM4 trans goes negative when we lost lock and powered down. The power scaling adjusted as such, and stopped adjusting when the rotation stage stopped moving, as it was supposed to do. If we want to use this channel, we'll have to add some logic to avoid this.

The rest of initial alignment went ok, I had to manual over the PRC offload check because the high useism. DRMI and PRMI aren't locking now, it looks like due to ground motion, but I'll have it try another initial alignment again and report back.

TITLE: 10/21 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Lock Acquisition
INCOMING OPERATOR: TJ
SHIFT SUMMARY: H1 was locked for most of my shift until the microseism eventually got too high. After that, I started troubleshooting issues with initial alignment that were eventually tracked down to be related to a commissioning change earlier in the day; TJ will have an alog with more on this. H1 is currently relocking up to DRMI.
LOG:

• 00:00 - Dropped observing from SQZ PMC unlocking
  • Guardians brought everything back automatically
  • Reapplied nominal damping gain for ETMX mode 1
• 00:05 - Observing
• 01:29 - Turned off ETMX mode 1 damping since monitor filter was ringing up again (see alog87585 for when this happened earlier today)
• 02:29 - Dropped observing to troubleshoot SQZ - alog87594
• 02:43 - Repplied nominal damping gain for ETMX mode 6 (it did not ring up again)
• 03:09 - Observing
• 03:22 - S251021u
• 04:27 - Lockloss - alog87595
  • Troubleshooting begins (see TJ's alog)

Follow up on the comissioning of the Length/Pitch OSEM estimator for PR3. 

I tuned up the pitch OSEM / Model filters and created some equivalent model filters for length. The functions that make the model and osem filters live in:
       blend_PR3_lengthv2_LP_est.m
       blend_PR3_pitchv2_LP_est.m

The files were committed to the SVN at (svnRoot)/sus/trunk/HLTS/Common/FilterDesign/Estimator/ under revision 12735. 

I saw that there is a new make_EST_blends function that will work nicely with these functions, so I will recommend using that one for getting these onto the real-time model.

Lockloss @ 04:27 UTC after 10+ hours locked - link to lockloss tool

Appears to be microseism-related. It's been coming up quickly over the past few hours, and have had several ETMY saturations off and on for the past 20 minutes while everything generally looked shaky.

I dropped H1 out of observing at 02:29 UTC so Sheila and I could try and touch up squeezing to hopefully improve the inspiral range.

We started by scanning the OPO temperature, but to try and stop the filter cavity from unlocking as it had been earlier today, lowered the scan amplitude on line 857 of the SQZ_OPO_LR Guardian from 0.015 to 0.007 and loaded the Guardian. Still, with just a couple seconds left in the scan, the filter cavity unlocked. The temperature didn't look like it needed changing though from the scan we did get, so we set it back to its previous setpoint. Then, we ran a SQZ angle scan with SQZ_MANAGER (after taking SQZ_ANG_ADJUST to 'IDLE') and decided an angle of about 165deg looked good, so we updated the angle servo setpoint on line 53 of sqzparams.py from 0 to -1 and loaded the SQZ_ANG_ADJUST Guardian. We set SQZ_MANAGER to do an alignment scan next, but forgot that the 'SCAN_ALIGNMENT_FDS' state does another angle scan to start. Since that scan ended with the angle in a quite different place that looked worse to us, we just put the angle back to 165 before the alignment scan started. After that, DARM high frequency BLRMs and inspiral range looked slightly better, so H1 resumed observing at 03:09 UTC.

Follow up to Oli's measurements on [LHO: 87362].

We fit the eight (yes, eight!) transfer functions needed for a full L-P M1 OSEM estimator for PR3. The measurements for PR3 were remarkably clean, so it was pretty close to just automated. I spent a lot of time cleaning up Ivey's code so it hopefully can be scaled up to other suspensions more easily.

The relevant fits are shown in the attached .pdf They are suspoint {L,P} to M1 {L,P} (4 fits), and M1 drive {L,P} to M1 {L,P} (4 fits). The estimator's control stability only depends on the M1 drive models, which are fit surprisingly well.

I will note that the L-P plant for PR3 is remarkably reciprocal, and I actually expect to see good performance of the estimators when we try them.

The fits were committed to the sus svn together with a script to install them under revision 12734.

The files live in (svnRoot)/sus/trunk/HLTS/Common/FilterDesign/Estimator/ and are named:

make_PR3_estimator_LP.m
fits_H1PR3_LP-2025-10-07.mat

_______________

These are the .zpk for the fits:

SUSPOINT TO M1
 
Suspoint L to M1 L fit
zpk([0,0,-0.223-4.338i,-0.223+4.338i,-0.04-7.231i,-0.04+7.231i,-0.122-15.233i,-0.122+15.233i],[-0.07-4.099i,-0.07+4.099i,-0.111-4.714i,-0.111+4.714i,-0.11-9.997i,-0.11+9.997i,-0.234-18.094i,-0.234+18.094i],-0.001)
 
Suspoint L to M1 P fit
zpk([0,0,0.954-6.919i,0.954+6.919i,-0.925-7.247i,-0.925+7.247i,-0.03-17.396i,-0.03+17.396i,-0.026-20.357i,-0.026+20.357i],[-0.083-4.115i,-0.083+4.115i,-0.09-4.669i,-0.09+4.669i,-0.107-9.984i,-0.107+9.984i,-0.288-13.181i,-0.288+13.181i,-0.275-18.054i,-0.275+18.054i,-0.084-22.109i,-0.084+22.109i],0.373)
 
Suspoint P to M1 L fit
zpk([0,0,-0.204-4.277i,-0.204+4.277i,-0.081-9.662i,-0.081+9.662i,0.016-17.983i,0.016+17.983i],[-0.044-4.018i,-0.044+4.018i,-0.102-4.661i,-0.102+4.661i,-0.028-9.938i,-0.028+9.938i,-0.018-18.044i,-0.018+18.044i],0)
 
Suspoint P to M1 P fit
zpk([0,0,-0.02-4.046i,-0.02+4.046i,-0.005-4.779i,-0.005+4.779i,0.017-5.716i,0.017+5.716i,0.003-9.719i,0.003+9.719i,-0.175-9.79i,-0.175+9.79i,0.075-13.176i,0.075+13.176i,0.001-22.098i,0.001+22.098i],[-0.01-4.018i,-0.01+4.018i,-0.06-4.157i,-0.06+4.157i,-0.06-4.653i,-0.06+4.653i,-0.007-4.797i,-0.007+4.797i,0-9.765i,0+9.765i,-0.017-9.957i,-0.017+9.957i,-0.036-13.12i,-0.036+13.12i,-0.019-22.115i,-0.019+22.115i],-0.001)
 
 
M1 DRIVE TO M1
 
M1 drive L to M1 L fit
zpk([-0.137-4.329i,-0.137+4.329i,-0.017-5.169i,-0.017+5.169i,-0.037-12.394i,-0.037+12.394i],[-0.098-4.128i,-0.098+4.128i,-0.09-4.66i,-0.09+4.66i,-0.103-9.985i,-0.103+9.985i,-0.245-18.089i,-0.245+18.089i],0.142)
 
M1 drive L to M1 P fit
zpk([1.391-5.654i,1.391+5.654i,-1.723-6.019i,-1.723+6.019i,-9,12.605,0.233-16.247i,0.233+16.247i,-0.042-19.777i,-0.042+19.777i],[-0.093-4.125i,-0.093+4.125i,-0.088-4.646i,-0.088+4.646i,-0.102-9.984i,-0.102+9.984i,-0.292-13.17i,-0.292+13.17i,-0.264-18.072i,-0.264+18.072i,-0.085-22.117i,-0.085+22.117i],0.119)
 
M1 drive P to M1 L fit
zpk([1.425-5.579i,1.425+5.579i,-1.619-6.117i,-1.619+6.117i,-9.724,13.511,0.26-16.388i,0.26+16.388i,-0.122-19.664i,-0.122+19.664i],[-0.092-4.129i,-0.092+4.129i,-0.097-4.664i,-0.097+4.664i,-0.081-9.967i,-0.081+9.967i,-0.298-13.165i,-0.298+13.165i,-0.27-18.058i,-0.27+18.058i,-0.08-22.14i,-0.08+22.14i],0.115)
 
M1 drive P to M1 P fit
zpk([-0.068-4.408i,-0.068+4.408i,-0.012-5.489i,-0.012+5.489i,-0.108-10.011i,-0.108+10.011i,-0.023-21.169i,-0.023+21.169i],[-0.089-4.125i,-0.089+4.125i,-0.079-4.666i,-0.079+4.666i,-0.104-9.96i,-0.104+9.96i,-0.29-13.181i,-0.29+13.181i,-0.084-22.141i,-0.084+22.141i],82.922)
 
 

Saturday standard coordinated calibration sweep

BB Start: 1444847709

BB End: 1444848020

Simulines Start: 1444848233

Simulines End: 1444849630

2025-10-18 19:06:16,282 | INFO | Finished gathering data. Data ends at 1444849593.0
2025-10-18 19:06:16,498 | INFO | It is SAFE TO RETURN TO OBSERVING now, whilst data is processed.
2025-10-18 19:06:16,498 | INFO | Commencing data processing.
2025-10-18 19:06:16,498 | INFO | Ending lockloss monitor. This is either due to having completed the measurement, and this functionality being terminated; or because the whole process was aborted.
2025-10-18 19:06:52,301 | INFO | File written out to: /ligo/groups/cal/H1/measurements/DARMOLG_SS/DARMOLG_SS_20251018T184336Z.hdf5
2025-10-18 19:06:52,309 | INFO | File written out to: /ligo/groups/cal/H1/measurements/PCALY2DARM_SS/PCALY2DARM_SS_20251018T184336Z.hdf5
2025-10-18 19:06:52,314 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L1_SS/SUSETMX_L1_SS_20251018T184336Z.hdf5
2025-10-18 19:06:52,319 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L2_SS/SUSETMX_L2_SS_20251018T184336Z.hdf5
2025-10-18 19:06:52,324 | INFO | File written out to: /ligo/groups/cal/H1/measurements/SUSETMX_L3_SS/SUSETMX_L3_SS_20251018T184336Z.hdf5
PDT: 2025-10-18 12:06:52.452839 PDT
UTC: 2025-10-18 19:06:52.452839 UTC
 

CALIBMONITOR attached (took screenshot after requesting NLN_CAL_MEAS - might be a mistake but do not know)

Jennie W, Sheila,

I took a long time to post this as have been working on other things...

We carried out a test (see LHO alog #86785) to look at the effect of DARM offset stepping on the power at OMC-DCPD_SUMS and OMC-REFL (transmitted through and reflected from the OMC). We did this with the heater on OM2 off as is nominal.

We then meant to redo these measurements once we heated up OM2 to change the mode-matching of the IFO to the OMC.

Unbfortunately we lost lock at about 15:06 UTC while Corey was taking out first measurement before heating up the OM2.

The meausrement is shown in this image, I have mislabelled it as 'third measurement' but it was the first. The optical gain is shown just before this measurment to be 0.994.

Then we waited as long as we could under out initial parameters of being finished cooling the OM2 again by 1:45pm.

We took another measurement at 1 hr 25 mins into lock after two false starts where I forgot to turn off the ASC. The optical gain was measured right before we started the measurements to be 0.978 but was still thermalising.

And then we took a third 2 hrs 59 minutes into lock, the IFO should be thermalised but the temperature of OM2 was still trending upwards a bit. Optical gain was 0.986.

We can use the slope of the power at the antisymmetric port (P_AS) vs. the power at the DCPDs (P_DCPD) as the DARM offset changes to estimate the throughput of carrier through the OMC which allows us one estimate of the loss.

The plots of this throughput are here for the cold state (minus the points taken after we lost lock), here for the partially thermalised state, and here for the thermalised state.

I am also in the middle of using the plot of P_AS varying with power at the OMC reflected port (P_REFL) to get a better estimate of the mode-mis match between the interferometer and the OMC.