Today at ~11:10 am, IP3 (LVEA 2x 1250 l/s IP) failed leading to a slight pressure rise in the corner. Seen on all LVEA pressure gauges (BSC2, HAM6, etc.). Attached snapshot shows the two pumps behavior at the time of failure, pump ion current on left column, output voltage on right.

Gerardo and I went to the mechanical room to diagnose the controller, upon arrival both channels on the Dual Vac controller had tripped off. We reset the high voltage and powered on the IP. Channel 1 (corresponding to Pump A in CDS) would only reach 300 V and then would trip the controller. Channel 2 (Pump B would reach 7kV no issue but would trip when Channel 1 tripped). We then swapped to a Gamma MPC controller to test if the controller was the problem. We saw the same exact behavior where Pump A would only reach 300V and Pump B was ok at 7kV.

We then swapped back to the DualVac controller after confirming it was not the issue, but with only Pump B connected and powered on. We are continuing to monitor to make sure Pump B remains steady. In parallel, Travis and Mark are testing the HV cable to the pump to see if there are any shorts. Results to follow.

If the cable is not the culprit we will HiPot the pump to see if there are any shorts, pump will be isolated from main volume during this test. To be continued.

I changed that way that the SQZ_MANAGER SCAN_SQZANG gen state worked to now take a brms_channel argument. Nominally for SCAN_SQZANG_FDS this is SQZ-DCPD_RATIO_3_DB_MON which tunes the squeezing around the 350Hz BLRMS to give the max IFO range. This is not yet tested, changes in SQZ_MANAGER.py svn.

I added a new state SCAN_SQZANG_KHZ (state number 85) from FIS that uses SQZ-DCPD_RATIO_6_DB_MON to maximize sqz at high frequency ~1700Hz. It makes sure ASC is off before scanning angle and can be be used when we take a sqz data set with SRCL offset steps e.g.  83569 to make 83572 brontosaurus plots.

To take SRCL offset FIS dataset (e.g. 83569):

• No SQZ (for subtraction in models)
  • Good time to measure NLG (instructions in 76542) and change NLG if wanted,
  • For SRCL offset measurements, increase NLG (NLG of 52 used in 83569 by increasing sqzparams OPO trans setpoint up to 120uW, SHG waveplate might need adjusting)
• Take IFO to FREQ_INDEP_SQZ
• For each SRCL offset:
  • Turn off SQZ ASC (H1:SQZ-ASC_WFS_SWITCH)
  • Change SRCL offset H1:LSC-SRCL1_OFFSET (prev used 0, -90, -190, -290, -390)
  • Go to SCAN_SQZANG_KHZ, will take 2mins (can check scan data at /ligo/www/www/exports/SQZ/GRD/SQZANG_SCAN/)
  • Go to FREQ_INDEP_SQZ, ASC should turn on as long it's in on in sqzparams, let it converge for ~1minute
  • Take 3 minutes of data, without glitches, note time down.

Take NLG back to nominal ~11, once done.

As a part of trying to diagnose what could be wrong with CHARD Y, I checked the ITMY A2L gains, in case they were so far off that it was responsible for some of the instabilities we've seen. Just based on the magnitude of the changes, I don't think it has been causing any problems.

While we sat at 25 W, after the move spots was completed, I drove a pitch and yaw dither on ITMY using the DOF2 paths in the ADS bank. The pitch line was driven at 19.125 Hz with a magnitude of 5000 and the yaw line at 21.287 Hz with a magnitude of 3000.

I made steps of 0.2 in both the pitch and yaw gains in both directions, and watched the line heights change. I was able to make the lines both higher and lower, so I am convinced that I am at least close to, if not at the minimum. Overall, the change in the gains is not that significant, so I think that it wasn't causing us any problems.

In the screenshot below, cursors mark the location of each line on the red trace.

Sheila Ryan and I phased LSC-REFL_B while we were sitting at 25W after move spots. We used the template in /opt/rtcds/userapps/release/lsc/h1/templates/CARM/check_refl_a_9_phase.xml and adjusted the phase which you can find in the LSC electronics overview. Screenshots of the 200Hz excitation after phasing and the sdf screenshot attached.

Daniel, Kevin, (Erik, Dave), Vicky

Kevin is interested in taking ADF sweeps around the second higher order mode arm resonance near 10.4 kHz.

We (Daniel) made model changes in h1ioplsc0 and h1omcpi that should enable higher freq ADF demods. Daniel built the models successfully. Then Dave also built these models successfully for the custom RCG running on h1omcpi for the variable duotone. We put in a WP to boot in these changes to h1ioplsc0 and h1omcpi next Tuesday 6/10.

From h1ioplsc0, we added 2 new PCIe channels to write the digital ADF LO oscillator out to PCIe. These are H1:IOP-PCI_ADF_VCXO_{COS,SIN} in screenshot 1. We also changed a rogue limiter such that the ADF should be able to scan +/-1 MHz according to the PLL.

In h1omcpi, we use the fast 64 kHz OMC PI user model to do a fast digital demodulation of the OMC_DCPD_SUM signal using the above ADF-LO PCIe channels. This is beating the fast dcpd output signal (H1:OMC-PI_DCPD_64KHZ_AHF), against the ADF LO's cosine and sine components from PCIe (H1:IOP-PCI_ADF_VCXO_{COS,SIN}), to get the demodulated ADF I/Q signals. The demod signals will have names like H1:OMC-PI_ADF_DEMOD_{I,Q}. Screenshots 2-4.

Operationally nothing should change for the ADF or for OMC-based fast PI damping. We are just using PCI to send 2 IPC channels from an IOP model to a user model on a different computer at ~65kHz, and doing the demod in a 64kHz user model (but the demod does not go anywhere, it is just used for squeezer diagnostics).

Sheila, Elenna, Caroline, Julia

We tested and reconfigured the DRMI ASC, and now we can run all of the DRMI ASC!

I trended the POP A offset yesterday to determine what the new values should be based on the alignment of the PRM once we are in full lock. I set those so we can use the PRC1 ASC loop (attachment 1 and attachment 2).

Then, we sat with DRMI locked and Sheila and I tried moving around PR2, IM4 and PRM to check if the error signals made sense. PRM uses POP A QPD, IM4 and PR2 use REFL A and B 9 MHz signals. We found that the PR2 and IM4 error signals seemed flipped, so we checked all of the REFL WFS signals and even thge POPX signals to see what might be the best new sensing matrix. Eventually, we chose to remain on REFL 9 I, but we flipped the sensing.

We were able to engage all the SRC ASC, except that after a minute or two og engagement, we saw an oscillation in the SRC signals. We eventually turned down the SRC1 P and Y gains, and the SRC2 P gain.

I tried moving the PRM to confirm the PRC1 error signal was ok, and I found that the pitch offset I chose was good, but the yaw offset was not good. So instead I moved the PRM yaw to maximize the buildups, and then reset the the POP A yaw offset (attachment 3).

Then, Sheila and I tried engaging the PRC2 and INP1 yaw ASC, but used the wrong sign for PRC2 Y and caused the DRMI lockloss. Luckily, we quickly recovered, and changed the sign and reengaged. We followed a similar procedure for the pitch ASC, but I stepped PR2 a few times to ensure the sign of the input matrix was correct.

We were then able to engage all the DRMI ASC, using lower SRC1 and SRC2 gains to prevent ringing. Sheila updated the ISC DRMI guardian to use these new input matrix values.

Except for some overall magnitude, the DRMI INP1 and PRC2 sensing has had this change in both pitch and yaw:

old sensing: INP1 = + REFL 9I A - REFL 9I B and PRC2 = +REFL 9I A + REFL 9I B

new sensing: INP1 = +REFL 9I A + REFL 9I B and PRC2 = -REFL 9I A + REFL 9I B

With the ASC engaged, we were able to raise the SRC1 pitch and yaw gains back to their nominal values (updated again in guardian). The SRC2 P loop still has a lower gain.

After attention was called to the uneven trending in the temperature of Zone 2A, I checked the heating coil and found that while the automation system was calling for 100% heating, the unit was not heating at all. I found that one of the 40 amp line voltage fuses had blown. This fuse also supplies line voltage to the control transformer which powers the control board, meaning the entire duct heater was down. Further troubleshooting is needed to find the cause of the blown 40 amp fuse, which will likely involve replacing heating elements.  

I updated the POP_A P and Y offsets so the DRMI ASC will take us closer to where the full IFO ASC will take us

• First screenshot of the POP inmon starting at DRMI_ASC, with a time cursor at full IFO ASC
• Second screenshot of the SDF - I'm fairly certain this is SDF controlled and not guardian controlled

FAMIS 25805

pH of PSL chiller water was measured to be between 10.0 and 10.5 according to the color of the test strip.

Betsy, Ryan S, TJ

We did our first walk through after the vent, but next week there will definitely be more to sweep that we either missed or that we said we will hold off a week on. We focused on the most egregious items.

• HAM6 +X-Y cables resting on HEPI cross beam, addressed
• HAM6 +X camera cables and power supplies. There are two cables going to AS Air and only one to OMC Trans. The AS Air cables are messily running down to the floor and to a power supply plugging into a 120V AC outlet. Perhaps this is a temporary setup? The OMC Trans cable get draped over the chamber's viewports.
• HAM6 +Y accellerometer cable roll moved off of the HEPI cross beam.
• HAM4 +X -Y cables on cross beam and curtains barely missing. These were not moved.
• SQZT0 table door handle was very loose and the door could move ~1/2". I quickly opened the table and tighened the handle up with a flat head. This should probably get some locktite at some point.
• BS Oplev cabling and driver. Chaotic cables and new driver. Jason will address this next week.
• HAM1/2 HEPI cross beam cables touching. These also were not address.
• 4 unused extension cords unplugged in HAM2/3 area
• Dust monitors turned off. These are the style with internal pumps, so they are turned off for low noise. Their network cables will need to be moved back to pumpless monitors.
  • HAM1 monitor off
  • BSC8 monitor off
• HAM3 cleanroom turned off by unplugging, fan and lights both off now.
• Dial indicator still connected to chamber (no picture)

Jonathan, Nyath

As per WP 12580 we have replaced the GC switch which interfaces with CDS.  This is in response to the need to cycle the switch twice on Friday.

Unfortunately this took more work than expected.  The first switch we tried was not passing data between the CDS router and the GC core.  So we are running a smaller spare CDS switch with POE + 10Gb capability to service the control room phones, the control room computers, and the DMT interface.

We have two fiber pairs going to the GC core switch.  We typically run them as an aggrigated link.  However for testing we have split that up and are running one pair to the active switch and have the other fiber pair to test another switch.

This work resulted in minor outages to the DMT and control room.  The largest outages being to the non-operator phones.

We will keep the work permit open for a bit.

Attatched to this alog are omicron glitch rate comparions, as a function of frequency and SNR, between O4a and O4b. Here, I used roughly ~ 3425 hours of observing time for O4a and O4b (H1:DMT-ANALYSIS_READY:1 flag). The specific observing times used were:

O4a: 2023-06-24 20:00:00 - 2024-01-17 00:00:00 (~3422 hours observing)

O4b: 2024-04-10 00:00:00 - 2025-01-28 17:00:00 (~3428 hours observing)

The SNR and frequency of the omicron triggers gathered were 7.5 < SNR < 500, and 10 Hz < frequency < 1024 Hz. I find that the glitch rate in O4b is significatly less than O4a. In O4a, there was a lot of non-stationary noise from ~10-50 Hz (see alogs 71005 & 71092), which is why the rate was so high. For frequencies below 50 Hz, the glitch rate per hour went from roughly  ~16.7 in O4a to ~2.5 in O4b. For SNR below 50, the glitch rate per hour went from ~36 per hour in O4a to ~9 per hour in O4b. 

Tue Jun 03 10:11:02 2025 INFO: Fill completed in 10min 59secs

HAM1 annulus system appears to have issues pumping down, currently its annulus ion pump is railed 10 mA, and the pump cart pumping on this system is sitting at 6.04x10^-05 Torr, see attached photo.

Process thus far:

• Last Thursday I managed to go and visit some of the -Y door bolts, found out that most of the bolts from 3 to 7 O'clock were not tigth, I was able to get 90 degrees turn, one bolt was actually loose, I was able to turn it by hand, but those were the only one that I was able to work on, since I was asked to stop work at HAM1.
• Another test done was to check for leaks on the aux cart pumping line, so the cart was isolated via the annulus system isolation valve, the pressure dropped at the aux cart down to 4x10^-06 Torr, meaning that no leak is on the pumping side, the isolation valve was opened again to continue pumping.

I plan to visit HAM1 to check the rest of the bolts on -Y door and +Y door.

Jennie W, Sheila, Elenna

In order to get data for mode-matching and for Elenna to get data to calibrate sideband heights we ran some mode scans after the SR3 heater was turned on last night.

16:55:24 UTC Carried out single bounce OMC scan at 10W PSL input with sensor correction on HAM6 on, high voltage on for PZT driver in HAM6, sidebands off , SRM mis-aligned, ITMY mis-aligned, DC 3 and 4 on, OMC ASC on.

Excitation freq changed to 0.005 Hz as the top peak of the TM00 mode looked squint so could have been saturating. Lowering this frequency prevented this.

Ref 15-17 corresponds to dcpd data, pzt exc signal, pzt2 dc monitor.

Then mis-aligned ITMX and aligned ITMY (Sheila had to re-align SR2 to centre on ASC-AS_C).

Measurement starts at 17:08:18 UTC.

Ref 18-20 corresponds to dcpd data, pzt exc signal, pzt2 dc monitor.

Traces saved in 20250516_OMC_scan.xml. The top left plot is the first scan bouncing beam off ITMX, the second scan is the bottom right bouncing off ITMY.

The top right is the two plots of the PZT2 DC voltage monitor. That is, the current voltage applied to the PZT. The bottom left is the plot of the voltage ramp applied to the PZT2 on the OMC for this measurement.

The ndscope attached shows the power in mA transmitted through the OMC on the top, then the PZT used for the scan DC voltage underneath, then the input PZT voltage underneath that, then the reflected power from the OMC in mW, then at the bottom the SR3 heater element temperature in degrees.

Elenna did two more scans in single bounce with sidebands back on and different modulations depths in each.

TJ, Camilla, Sheila

TJ and Camilla got the HWSs working, and now we turned on the SR3 heater at 15:54 UTC, 2W requested power.  This is to do a check of the SR3 heater calibration and range similar to 27262