Since we swapped the CO2X chiller for a new chiller 24 Oct 73704 (2nd t-cursor), the CO2X chiller has unlocked around once per week, mainly on Tuesdays and although is still decreasing in power, appears a lot more stable, plot attached.  

The CO2X laser power really stopped unlocking and decreasing after the unlock 10 Oct (1st t-cursor), on this day we swapped the HWS SLEDs (shouldnn't effect CO2's but is in same rack as CO2X) and both CO2 lasers tripped off (there was Beckhoff OM2 work). 

TITLE: 12/01 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Microseism
OUTGOING OPERATOR: Oli
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 4mph Gusts, 2mph 5min avg
    Primary useism: 0.06 μm/s
    Secondary useism: 0.57 μm/s
QUICK SUMMARY:
PSL Dust Mon Alerting when I arrived.
ISC_Lock is in Idle The MicroSeism has been very high.
I'm going to try to Lock the IFO.

TITLE: 12/01 Eve Shift: 00:00-08:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Microseism
INCOMING OPERATOR: N/A
SHIFT SUMMARY:

H1 has been unable to lock for the entirety of the shift due to the high microseism. We tried to lock at around 01:20 with a slightly different seismic configuration, but to no avail.

H1 remains in 'IDLE'.

LOG:

No log for this shift.

H1 is still down from very high microseism, and it doesn't look to be coming down at all. The wind speeds have come up slightly as well; nothing above 10mph gusts though.

Tried locking with a slightly different CPS FF seismic configuration at Jim's recommendation a couple of hours ago, but still couldn't get past LOCKING_ALS.

Been snowing on site for the past few hours, first of the season!

Our high microseisms are, I think, typically produced by storm waves and their reflections off of the nearby coast or, less often, from the global microseism generating regions near Greenland or the Aleutian islands. We can distinguish between these by matching the wave periods in global maps to the microseismic peak frequency that we detect, and by the propagation direction. When the dominant microseism is from our coast, it affects the two arms about equally, when it is from the Aleutian island region it travels down the X-arm and there is little relative motion along the Y-arm, and when, like today, it is from the region near Greenland, it travels along the Y-arm and there is little relative motion between the stations on the X-arm. I wonder if the lack of relative motion along one of the arms could be used to improve our performance during these periods...  The figure shows today's spectra from our 5 stations and the phase delays between the corner and out-stations, as well as maps estimating the wave height and wave period for today.

Wave models: https://mag.ncep.noaa.gov/model-guidance-model-parameter.php?group=Model%20Guidance&model=GEFS-WAVE&area=ATL-PAC&ps=area

[Aidan, Marie, Camille]

We measured the change in curvature of the PSAMS as a function of applied PZT voltage and applied preload torque. The measured defocus is the total defocus accumulated upon reflection.

The relevant values are: 

• PZT voltage: dS/dV = 0.87 mD/V (milli-diopters per volt)
• Preload: dS/dT = 2.4 mD/in.lb (milli-diopters per in-lb of torque

During the measurement of the torque values, we think we shifted/bumped the stage at one point which introduced an offset into the measurements, but did not change the slope of defocus vs torque.

The PSAMS was measured by illuminating it with a 520nm collimated green laser, then using a 1:1 image relay telescope (f1 = f2 = 500mm) to put a conjugate plane of the PSAMS surface onto the HWS. The HWS then measured changes in the incident curvature.

The data is attached in a zip file with an Jupyter notebook for doing the analysis. Data is stored in 4 columns:

# Preload (in-lb), Voltage (V), X-Defocus (D), Y-Defocus(D)

Defocus vs PZT voltage

Defocus vs Preload Torque

ASC loops at three times are compared are below in DTT, all 0-232Hz, 0.05Hz BW with 50 averages and 45% overlap for ~ 8 minutes of data used. Good DARM: 2023/11/23 6:45UTC; Fuzzy Darm: 2023/11/23 7:15UTC; Bad Low Freq DARM: 2023/11/30 7:45UTC (useism high) range 140MPc.

• DHARD P and DHARD Y can see factor of 2 increase in P and Y between 5-8Hz on 11/30, on DTT (doesn't look as bad on ipynb?!) Some peaks in DHARD Y.
• CHARD Y has some peaks around 7.7, 10.8, Hz
• CSOFT, DSOFT are similar.

Reused Jenne's 64760 rubbing script for these loops with 10minutes of data. PDFs attached. Comparing to 2023/11/23 6:45UTC good DARM time:

• Recent 2023/11/30 7:45UTC you can see the differences listed above and other low-freq differences
• Last weeks 2023/11/23 7:15UTC DARM fuzz, there is no differences

TITLE: 11/30 Eve Shift: 00:00-08:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Microseism
OUTGOING OPERATOR: Ibrahim
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 3mph Gusts, 2mph 5min avg
    Primary useism: 0.30 μm/s
    Secondary useism: 1.40 μm/s
QUICK SUMMARY:

H1 is down and ISC_LOCK in 'IDLE' due to very high microseism. If by some miracle it comes down during my shift, I'll attempt to lock.

TITLE: 11/30 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Microseism
INCOMING OPERATOR: Ryan S
SHIFT SUMMARY:

IFO is in IDLE due to high microseism impeding lock.

Secondary microseism is ~10x higher than nominal (likely due to 40ft waves off the Greenland coast). Primary microseism is getting worse due to bleeding from the secondary microseism. Picket fence also seeing this same elevated bleeding (intermittently).

There have been continued investigations into locking issues/locklosses/range instability from yesterday:

1. Oli's alog 74504: more details concerning AS72 Gain Locklosses, detailing how one of the locklosses since Tues Maint could have been caused by the gain increase (but perhaps not the others)
2. Ryan C's alog 74493: suspension noise OSEM spectra investigation with some interesting details concerning recent increases in noise. Discussions about this are ongoing.
   1. Camilla's alog 74494 is related to this same effort, but investigates the DARM noisiness during our last lock.
3. Other alogs in progress.

Other:

• Most watchdogs tripped due to some testing from Jim
• BRS tripped due to some seismometer work from Robert

Since we're in IDLE due to the microseism, there's no active testing on these investigations. Once the shaking earth decides to cooperate, we will attempt to relock and look out for these potential instability, poor range, poor lock causes.

LOG:

I ran Jenne's rubbing script using a reference time of us being in DOWN on the 22nd before the fuzziness started on the 23rd around 07:00UTC and a check time of 10:00UTC on the 23rd while also in DOWN, I didn't really see anything noteworthy, some noise increase in the 0.1Hz area (microseism)?

I also ran using the same reference time against a time this morning and there was a couple of suspensions that looked interesting, there were some spikes in the 1.0 - 10 Hz bandwidth for PR2, PR3, PRM, SR3, SR2, MC3, MC1, and OM3. In the 0.0 - 1.0 bandwidth the Quads saw an increase in noise, specifically the ITMs, TMSs, and ETMY. SRM and SR2 have some large spikes just under 1 Hz. The ITMs temperature has slightly increased, ~ 0.25 - 0.3 degrees F but these changes are less than 0.5 degrees so its probably not a worry.

Later in the day I ran the script a 3rd time using a time from yesterday (13:54UTC 11/29) with the same reference from the 22nd and most of the features I saw are no longer there, except for ITMX. Maybe the time I chose earlier was just a bad time?

I looked into the two locklosses from November 29th, 01:39UTC and 04:25UTC from during the time where the AS72 Gain was increased from 12dB to 21dB (74457), before it was reverted due to potentially having caused the next two locklosses.

It doesn't seem to me that both locklosses had the same cause, since there seems to be some discrepencies between the two locks as well as between the actual locklosses. Based on looking through the lockloss ndscopes, it looks like the first lockloss was probably caused by the AS72 gain, but I don't think the second one was, or at least wasn't the only cause. Here's a quick breakdown of some differences:

ASC Loops (ASC-01:39UTC, ASC-04:25UTC)
01:39 Lockloss - Signals look normal up to lockloss
04:25 Lockloss - Many signals are much larger than during the previous lock, and some are increasing in the last ~10s in the INMON channel.

LSC Loops (LSC-01:39UTC, LSC-04:25UTC)
01:39 Lockloss - LSC loops look much different than usual
04:25 Lockloss - Loops look pretty normal

SUS MASTER_OUTs (SUS-bothtimes, SUS-01:39UTC, SUS-04:25UTC)
01:39 Lockloss - MASTER_OUT channel values are more or less stable once in NOMINAL_LOW_NOISE
04:25 Lockloss - During last ~15minutes of lock, many MASTER_OUT values double and stay that large up to the lockloss

IFO is locking.

Difficulties with microseism locking persist (haven't been able to lock PRMI yet).

We stayed in idle for a bit to allow people to take some measurements (and also while Robert was near the BRS).

Just started our hopefully valiant second attempt.

Addressed TCS Chillers (Wed [Nov29] 415-430pm local) & CLOSED FAMIS #26162:

• TCSx Chiller:  Had level of 29.0 cm.  Added 330mL for 29.9cm.
• TCSy Chiller:  Had level of 9.4 cm.  Added 170mL for 9.9cm.
• There was no water in the small cup under the slow leak.

As suggested by Richard/Robert to look for electronics issues, I trended the SUS OSEMs before and after start of DARM Range Fuzzy period 2020/11/23 7:00UTC, between 6:00UTC and 8:00UTC and zoomed into [s-trends]. Previous troubleshooting in 74455, 74377, 74383.

Trended ZMs, IMs, RMs, OMC, OFI, OM1,2,3; ETMs, ITMs, @ M0,L2, L3; BS @ M1, L2, L3; MC1,2,3, SMs, PRs, FCs @ M1, M2, M3

I saw nothing change at the 2020/11/23 7:00UTC time. Only thing of note is that OFI, OM2, and ZM4,5,6 has louder periods every ~15 seconds, plots attached of ZMs and OM2. This is not a new feature.

TITLE: 11/30 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Lock Acquisition
OUTGOING OPERATOR: Ryan C
CURRENT ENVIRONMENT:
    SEI_ENV state: CALM
    Wind: 3mph Gusts, 2mph 5min avg
    Primary useism: 0.10 μm/s
    Secondary useism: 0.94 μm/s
QUICK SUMMARY:

IFO has been trying to lock DRMI (and failing) for about 3 hours (due to microseism).

PSL DUST 102 still acting up per previous alogs (74421).

Attempting to continue locking.