PI damping guardian has been edited to continue onto PI DAMPING after the first minute of OMC_WHITENING. Edits committed to SVN; diff and commit screenshot attached.

Due to the DCPD glitches from OMC_WHITENING, I had previously not engaged PI_DAMPING to turn on damping gains, coil drivers, etc during this lock stage. Oversight on my part, I didn't think about the case where we stay in that stage to damp violins for >1 hour. Violin damping looked really successful too, until PI24 ran away (nuc31 dcpds screenshot). I guess this shows that we indeed need active PI damping to avoid locklosses due to the 10.4 kHz PIs overlapping with the 2x HOMs.

Thu Jun 29 10:10:02 2023 INFO: Fill completed in 10min 1secs

Jordan confirmed a good fill curbside.

We've made it back to low noise but we are waiting to damp violins further before changing our OMC whitening. Not sure why the violin modes were rung up so bad from this lockloss.

TJ noticed the RefCav TPD was down around 0.83V this morning.  It's been hanging out around 0.9V, so it dropped over the last couple of days.  During relocking there were some issues at ALS, so to be on the safe side TJ asked me to tweak the RefCav beam alignment.  I was only able to get the TPD up to ~0.85V, so not much of an improvement (a whole 0.02V...).  This is an indication that we'll have to go into the enclosure to manually tweak the FSS path beam alignment on the PSL table, likely during the next maintenance window (July 11) or sooner if it becomes a problem (i.e. TPD continues to drop).  Will monitor.

Lockloss (tool link pending)

Ending our 42 hour long lock. No obvious cause.

TITLE: 06/29 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Observing at 139Mpc
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 4mph Gusts, 2mph 5min avg
    Primary useism: 0.01 μm/s
    Secondary useism: 0.06 μm/s
QUICK SUMMARY: Locked for almost 42 hours (O4 record). Plans for some commissioning time later today.

TITLE: 06/29 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 146Mpc
SHIFT SUMMARY: IFO has been locked for 42 hours. LHO's longest O4 lock so far.
LOG:

None of my owl shifts this week have needed me to do anything apart from Tuesday maintenance measurements from 7am.

There was again coherence between H1 range and wind speeds last night, see attached and yesterday's 70909.

Here's an updated BruCo scan after yesterday's commissioning activities 

https://ldas-jobs.ligo-wa.caltech.edu/~gabriele.vajente/bruco_GDS_1372064418/

• The A2L did not change much the coherence with CHARD_P and DHARD_Y
  • CHARD coherence might be related to HAM1 motion
• There is coherence with soft loops at 10 Hz: DSOFT_P and CSOFT_P
• Some coherence with INP1_P, similar pattern to CHARD_P, so maybe it's just cross coupling in the sensors
• SRCL is now out of the picture, but MICH could use some improvement
• Coherence with jitter is now lwoer (after the OM2 change)

Rachel McQueen, Camilla

Nominally each Ring heater lower segment has a RTD temperature sensor on it. These our the closest temperature sensors to the quad, in alog 46791 Aidan shows them witnessing LVEA temperature changes. Giving this status update as Rachel is looking into these sensors as part of her summer SURF project.

This is the current status of the sensors at LHO is below: only ETMX has a readback but this sensor is not attached correctly to the assembly.

• ITMX - Cable broke at sensor, free cable secured alog 9992, FRS 10482 c18
• ITMY - Was pinched and stopped working during ITMY swap Dec 2020 57519, see attached plot.
• ETMX - Not connected to structure, FRS 10482 c14, but otherwise reading back well..! Currently reporting 277K (39degF, 4degC) plot attached where you can see temperature change ~0.5K with each lock cycle.
• ETMY - Reported broken T1800421 suggests due to C&B or install. 2012 alog 3429 and 2018 alog 45187.

STATE of H1: Observing at 146Mpc. Locked for 38 hours.

TITLE: 06/29 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 148Mpc
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 12mph Gusts, 10mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.06 μm/s
QUICK SUMMARY:

23:12 Super event candidate S230628ax

00:19 UTC H1 Dropped out out of OBSERVING and into COMISSIONING due to the CAMERA_SERVO Guardian detecting that the ASC-CAM_PIT2_INMON & ASC-CAM_YAW2_INMON was "stuck" for 5 seconds. The Guardian node took itself to TURN_CAMERA_SERVO_OFF.  it was in this state for less than a minute. It then took itself back to CAMERA_SERVO_ON. Please See Alog.

00:34 UTC We went back to observing.

5:52 UTC H0:VAC-EX_INSTAIR_PT599_PRESS_PSIG alarm sounding off. Tagging Vacuum VE group.

Closes FAMIS 25072. Last done in alog 70652.

All V_eff values are remaining flat or trending towards zero. Comparison with Oplev charge Measurements also attached, although we still need to understand the relation between them both.

TITLE: 06/29 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 147Mpc
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 13mph Gusts, 11mph 5min avg
    Primary useism: 0.02 μm/s
    Secondary useism: 0.06 μm/s
QUICK SUMMARY: IFO locked for the past 34 hours, longest O4 H1 lock so far.

00:19 UTC H1 Dropped out out of OBSERVING and into COMISSIONING due to the CAMERA_SERVO Guardian detecting that the ASC-CAM_PIT2_INMON & ASC-CAM_YAW2_INMON was "stuck" for 5 seconds. The Guardian node took itself to TURN_CAMERA_SERVO_OFF. The Guardian node was in this state for less than a minute. It then took itself back to CAMERA_SERVO_ON. This was also seen in the Guardian log. Please See attached ndscope Screeneshot.

00:34 UTC We went back to observing.


Looking back at yesterdays alog, and some ndscopes this appears to be the same issue we saw today, and it was a mere coincidence that Elenna happen to hit the load button at the same time as the guardian node transitioned down to get the camera unstuck.

Naoki, Sheila

We measured the sqz, asqz, and mean sqz with current NLG as shown in the attached figure. The current OPO green trans is 85 and it corresponds to NLG of 12.6 and generated sqz of 15.5dB according to the calibration done on 2/3/23. 

To measure the mean sqz, we paused the SQZ MANAGER guardian and turned off SQZ ASC and took LO guardian down.

At 1kHz, squeezing is 3.7dB, mean squeezing is 10.4dB, and anti squeezing is 13.3dB.

We will measure the NLG with seed and try high NLG tomorrow.

Naoki, Sheila

After the OM2 change, the output alignment seems to change shown in alog70886 and this might have caused the SQZ ASC running away yesterday in alog70890. The last time we measured the SQZ ASC sensing matrix was 75W, cold OM2 in alog70308. So we measured the SQZ ASC sensing matrix again with 60W, hot OM2.

We kept the SQZ ASC WFS switch ON and turned off the input switch of the SQZ ASC filter bank. We measured the sensing matrix by stepping ZM5/6 P/Y by 100 count as shown in the first attached figure.

The sensing matrix changed a lot compared to previous sensing matrix. We calculated the inverse matrix and decided the new input matrix by multiplying the inverse matrix by -10 as follows.

The SQZ ASC works well with new input matrix. We accepted the new input matrix in SDF as shown in the second attached figure.

For cross correlation with 60W, hot OM2, we removed squeezing for 1 hour.

start: 1372017274 (2023/6/28 19:54:16 UTC)
end:  1372021147 (2023/6/28 20:58:49 UTC)

STATE of H1: Observing at 144Mpc. Been at NLN for 14 hours.