I've completed the upgrade of DAQ stat. New features ported from the old system are:

 - DC broadcast list check-sums must be identical

 - DC FE network port bandwidth must match within a tolerance

 - FWs disk usage is displayed, warnings issued to too large or too small

The MEDM was getting too tall to fit a 2k monitor, so the framewriter section was moved to the right.

Remaining task is to add the new channels to the DAQ next week.

Daniel tried to rebooted Beckhoff PC remotely, but it didn't come back so he rebooted it in MSR.

After that things came back mostly, there were two major exceptions:

1. JAC WFS whitening/dewhitening mismatch.

WFS whitening was off for two stages we use but the anti-whitening was on. WFS was at first turned on by the guardian when we tried to lock JAC and it totally misaligned it. We had to manually locked JAC, noticed that the alignment was off, cleared WFS history both in WFS feedback filters as well as JM1 lock filters, fixed the whitening/dewhitening mismatch by pressing "ON" buttons for two whitening stages, and after that it started working OK.

2. JAC got cooler, temperature servo overheats at first, and we're only getting 15 minutes lock stretches for now.

It took about 20 minutes for the Beckhoff to come back because the first reboot attempt didn't work (1st attachment). Thermistor 1 temperature dropped by about 0.05 degC as the temperature servo wasn't doing anything (2nd attachment, it looks like a sudden change but it's not, it's just that the Beckhoff EPICS numbers were frozen before that). Temperature servo started heating it hard as soon as it came back, overshot and tried to reduce heating, but it's still heating harder than it used to.  Because of that, JAC lock PZT voltage quickly goes to zero after relocking. We'll have to wait.

TITLE: 08/21 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: None
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 1mph Gusts, 0mph 3min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.10 μm/s 
QUICK SUMMARY: More alignment work expected today including attempting to fix clipping in the POP path. Beckhoff restart also expected this morning; the computer looks to have lasted the night. The X arm is currently locked in green with good IR flashes.

TITLE: 08/21 Eve Shift: 2330-0500 UTC (1630-2200 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY:

IFO is in IDLE at 2W

Ryan C informed me of the Beckhoff issue that will require an early morning computer restart (alog 91611). In the meantime, comissioners Elenna, Keita and Louis were working on alignment, specifically trying to solve a clipping issue related to PR2 in PRMI acquisition. 

During this, Elenna and Louis were putting IFO in single bounce IR with green arms on X to guage the alignment at the PRC. Then, they were going to pico. They'll continue tomorrow. Details in alog 91632

LOG:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        

[Elenna, Louis, + guidance from Sheila, Jenne, Keita, Camilla]

To investigate the POP clipping in 91549 we settled on a plan to pico in HAM3 while watching the POP pds and the ALS COMM beatnote. To do this we locked the x-arm in green and misaligned the y-arm. To get IR in HAM1 and on ISCT1 we set up single bounce using ITMX at 10W. 

We first had to adjust PM1 to get it centered on POP-X. This was done while locked on MICH dark. It took a while but we eventually got close enough for the POP-X centering to work. Once it did we offloaded the new positions onto the sliders. We rastered PM1 (pit, yaw) to demonstrate that we are hitting the maximum possible power on LSC-POP at the current alignment. We are getting predominantly 2f oscillations in POP-X but 1f in LSC-POP in both PIT and YAW, indicating that the beam is not completely well-centered on the LSC POP diode with the current upstream input alignment.

Once we had a reasonable beam on the POP pds and a reasonable COMM beatnote, we started pico's in the HAM3 POP path. We moved what felt like large distances in X without seeing any change in the POP pds or the COMM beatnote. We tried a bit in Y too but didn't go nearly as far. This was towards the end of the day so we reverted the pico positions (as much as we can trust them) and paused for the evening. We plan to continue pico'ing to better understand the clipping situation in the POP path.

Summary:

• Good news is that ALSY WFSA demod is working as far as fast channels go.
• Bad news is that something is broken about LO and RF level monitors.
• Another bad news is that Daniel found that Beckhoff PC needs rebooting very soon. We asked him to do that tomorrow.

Somewhat longer story:

Yesterday LO power for two out of four channels for ALSY WFSA demod (H1:ALS-Y_WFS_A_DEMOD_LOMONCHANNEL_3 and H1:ALS-Y_WFS_A_DEMOD_LOMONCHANNEL_4) were found missing. Attached trend shows that these channels were lost on July/16 at around 7:16AM local time, shortly after the power came back from the power glitch.

Fil and Daniel went to the end station and swap the chassis but only one channel was fixed, H1:ALS-Y_WFS_A_DEMOD_LOMONCHANNEL_3 was still bad.

Today I injected RF signal to the RF in of WFSA channel 3 and confirmed that the demod signal correctly appeared in both in H1:ALS-Y_WFS_A_I3_INMON and H1:ALS-Y_WFS_A_Q3_INMON. (For comparison I also injected into ch1 and saw the same response.)

I decided to leave it alone until Tuesday, but Daniel found that Beckhoff computer is in dire need for reboot. He said it MIGHT last for the night, it might not, and when the PC crashes it will affect many things but not PSL, and the wave plate rotator will be affected but will not move on its own after a crash. Since Louis and Elenna were working on pico-ing, we decided to try our luck.

Before going home I changed the laser power back to 2W. At this point the PC still seems to be running.

On Tuesday, August 18, and over the following two days, I installed the DAS fiber on the vacuum chamber and along sections of the LVEA floor with the help and guidance of Robert.

The DAS interrogator system is located at the H1 TCS Chiller and is connected to the LVEA through the mechanical cable tray. From there, the fiber is routed across the piping bridge and down beneath the vacuum chamber to the seismometer (SEI GND STS). At the seismometer location, we created a fiber loop to enable a direct comparison between the DAS and seismometer recordings.

The main objective is to compare the coherence between the DAS and seismometer measurements and to investigate the extent to which the intrinsic noise of the DAS system limits its performance in recording seismic and vibration signals.

From the seismometer, the fiber was routed back and attached to the vacuum chamber, with approximately five to six turns around the chamber. The fiber was then routed back to the seismometer, where an additional loop was created around the instrument. 

I also performed several tapping tests to georeference the DAS channels and identify the different sections of the fiber. Based on these tests, we were able to distinguish the individual fiber sections and associate them with their corresponding physical locations.

Photos of the installation are attached.

Jonathan, Dave:

daqstat was the last service to move off of h1daqscript0 (others were Dolphin network manager and daq_run_number_server). We powered this machine down at 16:30 today. I have temporarily greened the EDC by adding h1daqscript0's epics_load_mon channels to edc_green_ioc.

The LHO DAQ has three frame-writers. Two (FW0 and FW1) write to LDAS and have large disk arrays, the third (FW2) runs with a local disk and is used as a "tie breaker" if the two primary machines disagree with each other.

There are now 5 permutations of agreement between the 3 frame-writers:

All agree (0=1=2)

All disagree (0!=1!=2)

One disagrees with the other two ((0=1)!=2) ((0=2)!=1) and ((1=2)!=0)

Instead of a simple red/green LED indicator on the MEDM, we now have borders around each monitor which are red/green depending upon the agreement.

TITLE: 08/20 Day Shift: 1430-2330 UTC (0730-1630 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: Ibrahim
SHIFT SUMMARY: Multiple optics lab dust alarms throughout the day, corner alignment, we did not get to PRMI or DRMI as there was a ALS slow controls issue unlocking XARM. The main Beckhoff computer seems to be having connections issues, a restart is required to fix this, and it will be done tomorrow.
LOG:                                                              

• Started by aligning and locking the green arms, then Camilla and Elenna went out to improve the diff beatnote (-18 -> -11)
• 18:11 -19:22 UTC EQ mode from a 6.7 from Peru
• 19:37 UTC Automated phone call from Hanford regarding take cover drill today
  • Another call a few minutes later to terminate it
• ~20:00UTC manual initial alignment started
•  I was able to increase the power on ALSX by ~10/15%, up to ~0.75 while rechecking alignment after the earthquake

Jenne, Keita, Louis, Elenna

As noted in alog 91610, we struggled to use the green baffle scripts for setting the pointing of the ITMs.  We ended up doing the process of the baffle script by hand to set both ITMX and ITMY.  We did so with the IMC unlocked. 

I think the issue (or, at least a significant piece of it) is that the script is likely looking for the _NORMALIZED_ channel to have a peak at 1, but actually it's getting up to 10 or 12.  Also, at least with our (mis)alignment yesterday, the main beam was getting into the baffle PDs enough to send their values above 1, even without any actual green beam being on the PDs.  So, the script was "optimizing" the "green pointing" by looking at IR beam that was completely independent of any ITM pointing.

As I write all of this, I realize that I did not personally run the ISC_LOCK DOWN and SDF_REVERT states, so did not triple check that all the settings (eg PD gains) were set correctly.  We should check that before making modifications to the script.

Fix #1: We set the IMC to OFFLINE, so that we wouldn't get any IMC flashes.  This removed the IR beam from the equation, and the baseline level on the ETM baffle PDs went down to (or below) 0, rather than always being above 1.

Issue #2: Even with the IMC offline, the script would think things were close enough when the baffle PDs read a value above 1, even though that's actually on the edge of the PDs (whos peak values were closer to 10).  To solve this, we just did the optimization by hand (put the sliders to roughly the right place, engage the M0_TEST offsets with the appropriate values, then adjust the sliders to find the peak of the PDs).  We then noted the slider values, then put in the opposite TEST offsets for the other PD, and then re-adjusted the sliders to find the best place on the second PD.  There are a few options for fixing this for use with the script.  We can take the time to check that the gains are set correctly, such that the normalized value really should be going to 1.  Or, we can ask the script to look at the rough peak heights, and then use that as the peak value to be looking for before considering it optimized. This second option is certainly less reliable than the first option of just fixing the normalizations. 

Issue #3: For some reason that I don't understand, the values for the M0_TEST offsets, when applied to a well-aligned ITM, don't put you onto the ETM baffle PDs.  You still have to move the sliders.  I think this is equivalent to saying that when we applied those M0_TEST offsets and then optimized for the two baffles, we expect that the resultant slider values should be similar but they were not.  We averaged our resultant slider values, and used those for the ITM positions.  Someone should work to understand why these offsets aren't the correct values - has something changed?  Or maybe there was a setting somewhere mis-set?

Issue #4: I don't think that the baffle PD scripts have a catch point for ctrl-c and a graceful exit.  While we were running the script one of the times, we had a power glitch and tripped SEI and SUS at both end stations.  I ctrl-c'd, but that did not stop the excitations. Louis "took over" the EXC slots using awggui, and that successfully stopped the excitations.  We could have also killed the excitations.  Either way, it would be nice if the script was graceful about it (turn off excitations, put in the misalign offsets that gets done at the end of the script, set sliders back to original values).

Issue #5: A few times the script noted while it was doing things that it failed to find one of the baffle PDs.  That happens, not a big deal, and great that the script says so.  But, if that happens, it would be nice if the "the script has finished" message adds information about whether or not it successfully found both baffle PDs. 

Testing UTC Function of Alog. Working to correct reflection of UTC to PDT/PST time zone.

Summary

I calibrated the JAC WFS A/B RF signals into the complex misalignment amplitude at the JAC waist, using four angular calibration lines at 62 W (measurement of Aug 14). The sensing matrix agrees with the one measured on Aug 12 and with the layout. Converting the two WFS signals into the real and imaginary parts of the misalignment (δ^r = lateral shift at the waist, δⁱ = tilt), the displacement part dominates by a factor of 4–5, which is consistent with the dominant jitter source being the PSL which is far (~90 deg of Gouy phase) from the JAC waist.

One question remains: the locked WFS DC does not sense on the plane 90 deg from the RF where it should; the unlocked DC does. Second-order modes are the prime suspect and analysis ongoing.

1. Measurement

With the cavity locked at 62 W we injected four angular calibration lines and recorded WFS A and B (RF I/Q of all segments, and the DC segments). The raw spectra are in wfs_spectra_0814.png. Three records were taken: all lines on ("LAline"), length lines only ("Lline"), and no lines ("noline"), plus a dark record for the sensor floor. The line list is as follows:

The length lines are not for this post: they provide the demodulation reference for the double-demodulation signal, to be reported separately.

2. Sensing matrix in the actuator basis

From the heights of the four lines in each sensor we built the two 2x2 sensing matrix (actuator basis). The sensing-matrix vector figure is wfs_sensing_vectors_0814.png; it also carries the same measurement taken on Aug 12 and the layout-model prediction. The two measurement days agree very well. The model deviates by a few degrees per head (up to ~10 deg, table below), which we do not worry about, since WFS placement uncertainties and the actuators' own Gouy-phase uncertainties are of this order.

3. Sensor Gouy phases and the delta plane

The delta plane is the complex amplitude of the TEM10/01 content referenced at the JAC waist (accumulated Gouy phase = 0 there): the real axis is the waist lateral shift, the imaginary axis the tilt. An actuator kicking by an angle at accumulated Gouy phase η_a drives this amplitude with phase i·e^iηa; a sensor reads the projection of the amplitude onto its own axis.

Actuator parameters taken from the layout model (accumulated Gouy referenced to the JAC waist):

Solving each head's sensing axis from its response to the two actuators of its plane:

The actuator vectors and sensor axes on the delta plane are drawn in wfs_delta_plane_0814.png.

4. Calibrated input jitter

With these calibration I got the main plot(wfs_delta_spectra_0814.png.)  The two WFS signals inverted into the calibrated complex misalignment at the JAC waist, δ^r (lateral shift) and δⁱ (tilt).

• δ^r dominates δⁱ by 4–5x. This makes sense: the dominant jitter source is the PSL, in air and far away (about 90 deg of Gouy phase), so its angular jitter, entering as i·e^iη, lands on the real (displacement) quadrature.
• The structures above 100 Hz are coherent with the PSL periscope accelerometers, so they are caused by the PSL periscope.
• The broad bump below 10 Hz is most likely caused by air convection inside the PSL enclosure.
• The WFS picks up only about 5% of any post-JAC jitter (to be reported separately), so what is shown here is essentially the input jitter.

5. the locked DC

Calibrating the WFS DC the same way should give a sensing plane rotated 90 deg from the RF: the RF reads the tilt-like quadrature at its axis, the DC reads the beam position. But actually, tt does not. In wfs_sensor_gouy_states_0814.png the cyan/orange lines (locked-DC sensing axes) should lie on the blue/red dash-dotted lines (the RF axes rotated by 90 deg), but  they point 30–70 deg away. The same solve on an unlocked, clean beam lands within about 10 deg of the expectation, so the sensors themselves are fine: something in the locked field is doing it, and the second-order (mode-mismatch) content is strongly suspected.

The analysis of this signal is in progress and will be posted shortly. Stay tuned.

[Ryan C, Elenna, Matilda, Camilla, Louis]

We have locked each arm on green. Looks like the X arm build up on ALS TRX is about 0.6, and Y is about 1.2. The COMM beatnote is -3 dBm, and the DIFF beatnote is -20 dBm.

Going to LOCK SLOW GWFS ETM TMS on Y arm does not engage the WFS, but works, which means the slow controls do work on y arm. I guess the WFS are disengaged for now.

However, it appears the X arm slow controls are still not working. Going to no slow with green wfs on X arm requires going through a state that does engage the slow controls, so we're still sitting in "locking" on X arm.

Camilla and I are about to head to the table to touch up the DIFF beatnote.

We figured out how to engage the X arm WFS by hand and they are improving the buildup.

****

We (Camilla, Louis, Elenna) have aligned the DIFF beatnote to -11 dBm. The biggest move was ensuring the beam made it to the DIFF PD- Camilla found both edges of the PD using the steering mirror and centered the beam on the PD.

[Keita, Louis, Jenne, Elenna, others in CR]

We have locked both arms on green! Proof.

Jenne started running baffle PD scripts for TMSX and ITMX with Keita. There is some issue with ITMX baffle script, so Keita and Jenne walked through the process by hand (hopefully one of them will describe). Jenne was able to lock the green arms after aligning ETMX by hand. We don't think the slow controls are working, so we couldn't move beyond the "locking" state in the guardian.

While Louis and Jenne were running the y arm baffle scripts, there was a power glitch that tripped both end station HEPIs. We stood down while Ryan and Huyen went to reset them.

Louis had a hard time with the ITMY baffle PD script. I was able to move ITMY a large amount to find the March 5 2026 setting Jenne found here. This allowed Louis to finally find the beam on the baffle PDs. After a few iterations by hand and with the script, we settled on a setting that moved ITMY by 110 urad in pitch and 56 urad in yaw.

We could not see green flashes at ISCT1 from the y arm, because the beamsplitter is now very misaligned between the two ITMs due to the large ITMY move. First, I misaligned the Y arm and checked for the red beam on ISCT1 refl camera. I had to move IM4 to find it there. Then, Louis and I tried to move the beamsplitter around. We found that by putting ITMY back to its slider setting before the baffle PD script was run, we could move ITMY a bit towards the correct direction and follow with the beamsplitter. We also had to touch up SR2 to keep the beam on the AS AIR camera and roughly centered on AS_C.

(Travis, Gerardo)
The ion pump for HAM1 was incorporated to the HAM volume yesterday, and today the SS-500 pump cart was isolated from the chamber (turbo pump and SS-500 remain on), and as expected the pressure went up and now we are waiting for the ion pump to take over and maintain the vacuum pressure for HAM1.  We will be monitoring the progress of the ion pump.

(Travis, Gerardo)
This morning we checked HAM7 annulus system pumpdown and the aux-cart displayed 2.6X10^-05 Torr, good progress so it appears to be doing good.  We disconnected the SS-500 cart from HAM6 turbo and connected it to HAM7.  We checked all ports were "nominal", detached the active purge hose and no blowdown was done, since we had the relay tube valve (RV-2) open, took advantage of this and we let the purge air purge HAM7 overnight out RV-2.  After closing RV-2 we started the pumpdown of HAM7.  The purge valve (all metal valve) and the roughing valve at the turbo assembly were closed at 3.0X10^-05 Torr.
Attached is a plot of the pumpdown thus far.

Miranda, Dave:

Over the past week we have documented the LHO PEM accelerometers and produced an as-built  wiring drawing

This was in response to a possible misreading of accelerometer(s) with the wrong channel names.

We found three accelerometers with incorrect names, which date back to pre-O4, so I'm tagging DETCHAR.

We fixed this at 16:00 Thursday 13th August 2026 PDT by remapping the BNC connections on the front panel of APC1. The cable going to port12 was moved to port13, that going to port13 was moved to port14 and that going to port14 was moved to port12.

We tap-tested the EBAY_FLOOR accelerometer at 16:10 and this showed up on H1:PEM-CS_ACC_EBAY_FLOOR_Z_DQ